security/selinux/hooks.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Security-Enhanced Linux (SELinux) security module
   4  *
   5  *  This file contains the SELinux hook function implementations.
   6  *
   7  *  Authors:  Stephen Smalley, <stephen.smalley.work@gmail.com>
   8  *            Chris Vance, <cvance@nai.com>
   9  *            Wayne Salamon, <wsalamon@nai.com>
  10  *            James Morris <jmorris@redhat.com>
  11  *
  12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14  *                                         Eric Paris <eparis@redhat.com>
  15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16  *                          <dgoeddel@trustedcs.com>
  17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18  *      Paul Moore <paul@paul-moore.com>
  19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  21  *  Copyright (C) 2016 Mellanox Technologies
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/kd.h>
  26 #include <linux/kernel.h>
  27 #include <linux/kernel_read_file.h>
  28 #include <linux/errno.h>
  29 #include <linux/sched/signal.h>
  30 #include <linux/sched/task.h>
  31 #include <linux/lsm_hooks.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/swap.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/syscalls.h>
  43 #include <linux/dcache.h>
  44 #include <linux/file.h>
  45 #include <linux/fdtable.h>
  46 #include <linux/namei.h>
  47 #include <linux/mount.h>
  48 #include <linux/fs_context.h>
  49 #include <linux/fs_parser.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/inet_connection_sock.h>
  57 #include <net/net_namespace.h>
  58 #include <net/netlabel.h>
  59 #include <linux/uaccess.h>
  60 #include <asm/ioctls.h>
  61 #include <linux/atomic.h>
  62 #include <linux/bitops.h>
  63 #include <linux/interrupt.h>
  64 #include <linux/netdevice.h>    /* for network interface checks */
  65 #include <net/netlink.h>
  66 #include <linux/tcp.h>
  67 #include <linux/udp.h>
  68 #include <linux/dccp.h>
  69 #include <linux/sctp.h>
  70 #include <net/sctp/structs.h>
  71 #include <linux/quota.h>
  72 #include <linux/un.h>           /* for Unix socket types */
  73 #include <net/af_unix.h>        /* for Unix socket types */
  74 #include <linux/parser.h>
  75 #include <linux/nfs_mount.h>
  76 #include <net/ipv6.h>
  77 #include <linux/hugetlb.h>
  78 #include <linux/personality.h>
  79 #include <linux/audit.h>
  80 #include <linux/string.h>
  81 #include <linux/mutex.h>
  82 #include <linux/posix-timers.h>
  83 #include <linux/syslog.h>
  84 #include <linux/user_namespace.h>
  85 #include <linux/export.h>
  86 #include <linux/msg.h>
  87 #include <linux/shm.h>
  88 #include <uapi/linux/shm.h>
  89 #include <linux/bpf.h>
  90 #include <linux/kernfs.h>
  91 #include <linux/stringhash.h>   /* for hashlen_string() */
  92 #include <uapi/linux/mount.h>
  93 #include <linux/fsnotify.h>
  94 #include <linux/fanotify.h>
  95 #include <linux/io_uring/cmd.h>
  96 #include <uapi/linux/lsm.h>
  97
  98 #include "avc.h"
  99 #include "objsec.h"
 100 #include "netif.h"
 101 #include "netnode.h"
 102 #include "netport.h"
 103 #include "ibpkey.h"
 104 #include "xfrm.h"
 105 #include "netlabel.h"
 106 #include "audit.h"
 107 #include "avc_ss.h"
 108
 109 #define SELINUX_INODE_INIT_XATTRS 1
 110
 111 struct selinux_state selinux_state;
 112
 113 /* SECMARK reference count */
 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 115
 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 117 static int selinux_enforcing_boot __initdata;
 118
 119 static int __init enforcing_setup(char *str)
 120 {
 121         unsigned long enforcing;
 122         if (!kstrtoul(str, 0, &enforcing))
 123                 selinux_enforcing_boot = enforcing ? 1 : 0;
 124         return 1;
 125 }
 126 __setup("enforcing=", enforcing_setup);
 127 #else
 128 #define selinux_enforcing_boot 1
 129 #endif
 130
 131 int selinux_enabled_boot __initdata = 1;
 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 133 static int __init selinux_enabled_setup(char *str)
 134 {
 135         unsigned long enabled;
 136         if (!kstrtoul(str, 0, &enabled))
 137                 selinux_enabled_boot = enabled ? 1 : 0;
 138         return 1;
 139 }
 140 __setup("selinux=", selinux_enabled_setup);
 141 #endif
 142
 143 static int __init checkreqprot_setup(char *str)
 144 {
 145         unsigned long checkreqprot;
 146
 147         if (!kstrtoul(str, 0, &checkreqprot)) {
 148                 if (checkreqprot)
 149                         pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
 150         }
 151         return 1;
 152 }
 153 __setup("checkreqprot=", checkreqprot_setup);
 154
 155 /**
 156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 157  *
 158  * Description:
 159  * This function checks the SECMARK reference counter to see if any SECMARK
 160  * targets are currently configured, if the reference counter is greater than
 161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 163  * policy capability is enabled, SECMARK is always considered enabled.
 164  *
 165  */
 166 static int selinux_secmark_enabled(void)
 167 {
 168         return (selinux_policycap_alwaysnetwork() ||
 169                 atomic_read(&selinux_secmark_refcount));
 170 }
 171
 172 /**
 173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 174  *
 175  * Description:
 176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 177  * (1) if any are enabled or false (0) if neither are enabled.  If the
 178  * always_check_network policy capability is enabled, peer labeling
 179  * is always considered enabled.
 180  *
 181  */
 182 static int selinux_peerlbl_enabled(void)
 183 {
 184         return (selinux_policycap_alwaysnetwork() ||
 185                 netlbl_enabled() || selinux_xfrm_enabled());
 186 }
 187
 188 static int selinux_netcache_avc_callback(u32 event)
 189 {
 190         if (event == AVC_CALLBACK_RESET) {
 191                 sel_netif_flush();
 192                 sel_netnode_flush();
 193                 sel_netport_flush();
 194                 synchronize_net();
 195         }
 196         return 0;
 197 }
 198
 199 static int selinux_lsm_notifier_avc_callback(u32 event)
 200 {
 201         if (event == AVC_CALLBACK_RESET) {
 202                 sel_ib_pkey_flush();
 203                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 204         }
 205
 206         return 0;
 207 }
 208
 209 /*
 210  * initialise the security for the init task
 211  */
 212 static void cred_init_security(void)
 213 {
 214         struct task_security_struct *tsec;
 215
 216         tsec = selinux_cred(unrcu_pointer(current->real_cred));
 217         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 218 }
 219
 220 /*
 221  * get the security ID of a set of credentials
 222  */
 223 static inline u32 cred_sid(const struct cred *cred)
 224 {
 225         const struct task_security_struct *tsec;
 226
 227         tsec = selinux_cred(cred);
 228         return tsec->sid;
 229 }
 230
 231 static void __ad_net_init(struct common_audit_data *ad,
 232                           struct lsm_network_audit *net,
 233                           int ifindex, struct sock *sk, u16 family)
 234 {
 235         ad->type = LSM_AUDIT_DATA_NET;
 236         ad->u.net = net;
 237         net->netif = ifindex;
 238         net->sk = sk;
 239         net->family = family;
 240 }
 241
 242 static void ad_net_init_from_sk(struct common_audit_data *ad,
 243                                 struct lsm_network_audit *net,
 244                                 struct sock *sk)
 245 {
 246         __ad_net_init(ad, net, 0, sk, 0);
 247 }
 248
 249 static void ad_net_init_from_iif(struct common_audit_data *ad,
 250                                  struct lsm_network_audit *net,
 251                                  int ifindex, u16 family)
 252 {
 253         __ad_net_init(ad, net, ifindex, NULL, family);
 254 }
 255
 256 /*
 257  * get the objective security ID of a task
 258  */
 259 static inline u32 task_sid_obj(const struct task_struct *task)
 260 {
 261         u32 sid;
 262
 263         rcu_read_lock();
 264         sid = cred_sid(__task_cred(task));
 265         rcu_read_unlock();
 266         return sid;
 267 }
 268
 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 270
 271 /*
 272  * Try reloading inode security labels that have been marked as invalid.  The
 273  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 274  * allowed; when set to false, returns -ECHILD when the label is
 275  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 276  */
 277 static int __inode_security_revalidate(struct inode *inode,
 278                                        struct dentry *dentry,
 279                                        bool may_sleep)
 280 {
 281         struct inode_security_struct *isec = selinux_inode(inode);
 282
 283         might_sleep_if(may_sleep);
 284
 285         if (selinux_initialized() &&
 286             isec->initialized != LABEL_INITIALIZED) {
 287                 if (!may_sleep)
 288                         return -ECHILD;
 289
 290                 /*
 291                  * Try reloading the inode security label.  This will fail if
 292                  * @opt_dentry is NULL and no dentry for this inode can be
 293                  * found; in that case, continue using the old label.
 294                  */
 295                 inode_doinit_with_dentry(inode, dentry);
 296         }
 297         return 0;
 298 }
 299
 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 301 {
 302         return selinux_inode(inode);
 303 }
 304
 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 306 {
 307         int error;
 308
 309         error = __inode_security_revalidate(inode, NULL, !rcu);
 310         if (error)
 311                 return ERR_PTR(error);
 312         return selinux_inode(inode);
 313 }
 314
 315 /*
 316  * Get the security label of an inode.
 317  */
 318 static struct inode_security_struct *inode_security(struct inode *inode)
 319 {
 320         __inode_security_revalidate(inode, NULL, true);
 321         return selinux_inode(inode);
 322 }
 323
 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 325 {
 326         struct inode *inode = d_backing_inode(dentry);
 327
 328         return selinux_inode(inode);
 329 }
 330
 331 /*
 332  * Get the security label of a dentry's backing inode.
 333  */
 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 335 {
 336         struct inode *inode = d_backing_inode(dentry);
 337
 338         __inode_security_revalidate(inode, dentry, true);
 339         return selinux_inode(inode);
 340 }
 341
 342 static void inode_free_security(struct inode *inode)
 343 {
 344         struct inode_security_struct *isec = selinux_inode(inode);
 345         struct superblock_security_struct *sbsec;
 346
 347         if (!isec)
 348                 return;
 349         sbsec = selinux_superblock(inode->i_sb);
 350         /*
 351          * As not all inode security structures are in a list, we check for
 352          * empty list outside of the lock to make sure that we won't waste
 353          * time taking a lock doing nothing.
 354          *
 355          * The list_del_init() function can be safely called more than once.
 356          * It should not be possible for this function to be called with
 357          * concurrent list_add(), but for better safety against future changes
 358          * in the code, we use list_empty_careful() here.
 359          */
 360         if (!list_empty_careful(&isec->list)) {
 361                 spin_lock(&sbsec->isec_lock);
 362                 list_del_init(&isec->list);
 363                 spin_unlock(&sbsec->isec_lock);
 364         }
 365 }
 366
 367 struct selinux_mnt_opts {
 368         u32 fscontext_sid;
 369         u32 context_sid;
 370         u32 rootcontext_sid;
 371         u32 defcontext_sid;
 372 };
 373
 374 static void selinux_free_mnt_opts(void *mnt_opts)
 375 {
 376         kfree(mnt_opts);
 377 }
 378
 379 enum {
 380         Opt_error = -1,
 381         Opt_context = 0,
 382         Opt_defcontext = 1,
 383         Opt_fscontext = 2,
 384         Opt_rootcontext = 3,
 385         Opt_seclabel = 4,
 386 };
 387
 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 389 static const struct {
 390         const char *name;
 391         int len;
 392         int opt;
 393         bool has_arg;
 394 } tokens[] = {
 395         A(context, true),
 396         A(fscontext, true),
 397         A(defcontext, true),
 398         A(rootcontext, true),
 399         A(seclabel, false),
 400 };
 401 #undef A
 402
 403 static int match_opt_prefix(char *s, int l, char **arg)
 404 {
 405         int i;
 406
 407         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 408                 size_t len = tokens[i].len;
 409                 if (len > l || memcmp(s, tokens[i].name, len))
 410                         continue;
 411                 if (tokens[i].has_arg) {
 412                         if (len == l || s[len] != '=')
 413                                 continue;
 414                         *arg = s + len + 1;
 415                 } else if (len != l)
 416                         continue;
 417                 return tokens[i].opt;
 418         }
 419         return Opt_error;
 420 }
 421
 422 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 423
 424 static int may_context_mount_sb_relabel(u32 sid,
 425                         struct superblock_security_struct *sbsec,
 426                         const struct cred *cred)
 427 {
 428         const struct task_security_struct *tsec = selinux_cred(cred);
 429         int rc;
 430
 431         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 432                           FILESYSTEM__RELABELFROM, NULL);
 433         if (rc)
 434                 return rc;
 435
 436         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 437                           FILESYSTEM__RELABELTO, NULL);
 438         return rc;
 439 }
 440
 441 static int may_context_mount_inode_relabel(u32 sid,
 442                         struct superblock_security_struct *sbsec,
 443                         const struct cred *cred)
 444 {
 445         const struct task_security_struct *tsec = selinux_cred(cred);
 446         int rc;
 447         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 448                           FILESYSTEM__RELABELFROM, NULL);
 449         if (rc)
 450                 return rc;
 451
 452         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 453                           FILESYSTEM__ASSOCIATE, NULL);
 454         return rc;
 455 }
 456
 457 static int selinux_is_genfs_special_handling(struct super_block *sb)
 458 {
 459         /* Special handling. Genfs but also in-core setxattr handler */
 460         return  !strcmp(sb->s_type->name, "sysfs") ||
 461                 !strcmp(sb->s_type->name, "pstore") ||
 462                 !strcmp(sb->s_type->name, "debugfs") ||
 463                 !strcmp(sb->s_type->name, "tracefs") ||
 464                 !strcmp(sb->s_type->name, "rootfs") ||
 465                 (selinux_policycap_cgroupseclabel() &&
 466                  (!strcmp(sb->s_type->name, "cgroup") ||
 467                   !strcmp(sb->s_type->name, "cgroup2")));
 468 }
 469
 470 static int selinux_is_sblabel_mnt(struct super_block *sb)
 471 {
 472         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 473
 474         /*
 475          * IMPORTANT: Double-check logic in this function when adding a new
 476          * SECURITY_FS_USE_* definition!
 477          */
 478         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 479
 480         switch (sbsec->behavior) {
 481         case SECURITY_FS_USE_XATTR:
 482         case SECURITY_FS_USE_TRANS:
 483         case SECURITY_FS_USE_TASK:
 484         case SECURITY_FS_USE_NATIVE:
 485                 return 1;
 486
 487         case SECURITY_FS_USE_GENFS:
 488                 return selinux_is_genfs_special_handling(sb);
 489
 490         /* Never allow relabeling on context mounts */
 491         case SECURITY_FS_USE_MNTPOINT:
 492         case SECURITY_FS_USE_NONE:
 493         default:
 494                 return 0;
 495         }
 496 }
 497
 498 static int sb_check_xattr_support(struct super_block *sb)
 499 {
 500         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 501         struct dentry *root = sb->s_root;
 502         struct inode *root_inode = d_backing_inode(root);
 503         u32 sid;
 504         int rc;
 505
 506         /*
 507          * Make sure that the xattr handler exists and that no
 508          * error other than -ENODATA is returned by getxattr on
 509          * the root directory.  -ENODATA is ok, as this may be
 510          * the first boot of the SELinux kernel before we have
 511          * assigned xattr values to the filesystem.
 512          */
 513         if (!(root_inode->i_opflags & IOP_XATTR)) {
 514                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 515                         sb->s_id, sb->s_type->name);
 516                 goto fallback;
 517         }
 518
 519         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 520         if (rc < 0 && rc != -ENODATA) {
 521                 if (rc == -EOPNOTSUPP) {
 522                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 523                                 sb->s_id, sb->s_type->name);
 524                         goto fallback;
 525                 } else {
 526                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 527                                 sb->s_id, sb->s_type->name, -rc);
 528                         return rc;
 529                 }
 530         }
 531         return 0;
 532
 533 fallback:
 534         /* No xattr support - try to fallback to genfs if possible. */
 535         rc = security_genfs_sid(sb->s_type->name, "/",
 536                                 SECCLASS_DIR, &sid);
 537         if (rc)
 538                 return -EOPNOTSUPP;
 539
 540         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 541                 sb->s_id, sb->s_type->name);
 542         sbsec->behavior = SECURITY_FS_USE_GENFS;
 543         sbsec->sid = sid;
 544         return 0;
 545 }
 546
 547 static int sb_finish_set_opts(struct super_block *sb)
 548 {
 549         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 550         struct dentry *root = sb->s_root;
 551         struct inode *root_inode = d_backing_inode(root);
 552         int rc = 0;
 553
 554         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 555                 rc = sb_check_xattr_support(sb);
 556                 if (rc)
 557                         return rc;
 558         }
 559
 560         sbsec->flags |= SE_SBINITIALIZED;
 561
 562         /*
 563          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 564          * leave the flag untouched because sb_clone_mnt_opts might be handing
 565          * us a superblock that needs the flag to be cleared.
 566          */
 567         if (selinux_is_sblabel_mnt(sb))
 568                 sbsec->flags |= SBLABEL_MNT;
 569         else
 570                 sbsec->flags &= ~SBLABEL_MNT;
 571
 572         /* Initialize the root inode. */
 573         rc = inode_doinit_with_dentry(root_inode, root);
 574
 575         /* Initialize any other inodes associated with the superblock, e.g.
 576            inodes created prior to initial policy load or inodes created
 577            during get_sb by a pseudo filesystem that directly
 578            populates itself. */
 579         spin_lock(&sbsec->isec_lock);
 580         while (!list_empty(&sbsec->isec_head)) {
 581                 struct inode_security_struct *isec =
 582                                 list_first_entry(&sbsec->isec_head,
 583                                            struct inode_security_struct, list);
 584                 struct inode *inode = isec->inode;
 585                 list_del_init(&isec->list);
 586                 spin_unlock(&sbsec->isec_lock);
 587                 inode = igrab(inode);
 588                 if (inode) {
 589                         if (!IS_PRIVATE(inode))
 590                                 inode_doinit_with_dentry(inode, NULL);
 591                         iput(inode);
 592                 }
 593                 spin_lock(&sbsec->isec_lock);
 594         }
 595         spin_unlock(&sbsec->isec_lock);
 596         return rc;
 597 }
 598
 599 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 600                       u32 old_sid, u32 new_sid)
 601 {
 602         char mnt_flags = sbsec->flags & SE_MNTMASK;
 603
 604         /* check if the old mount command had the same options */
 605         if (sbsec->flags & SE_SBINITIALIZED)
 606                 if (!(sbsec->flags & flag) ||
 607                     (old_sid != new_sid))
 608                         return 1;
 609
 610         /* check if we were passed the same options twice,
 611          * aka someone passed context=a,context=b
 612          */
 613         if (!(sbsec->flags & SE_SBINITIALIZED))
 614                 if (mnt_flags & flag)
 615                         return 1;
 616         return 0;
 617 }
 618
 619 /*
 620  * Allow filesystems with binary mount data to explicitly set mount point
 621  * labeling information.
 622  */
 623 static int selinux_set_mnt_opts(struct super_block *sb,
 624                                 void *mnt_opts,
 625                                 unsigned long kern_flags,
 626                                 unsigned long *set_kern_flags)
 627 {
 628         const struct cred *cred = current_cred();
 629         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 630         struct dentry *root = sb->s_root;
 631         struct selinux_mnt_opts *opts = mnt_opts;
 632         struct inode_security_struct *root_isec;
 633         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 634         u32 defcontext_sid = 0;
 635         int rc = 0;
 636
 637         /*
 638          * Specifying internal flags without providing a place to
 639          * place the results is not allowed
 640          */
 641         if (kern_flags && !set_kern_flags)
 642                 return -EINVAL;
 643
 644         mutex_lock(&sbsec->lock);
 645
 646         if (!selinux_initialized()) {
 647                 if (!opts) {
 648                         /* Defer initialization until selinux_complete_init,
 649                            after the initial policy is loaded and the security
 650                            server is ready to handle calls. */
 651                         if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 652                                 sbsec->flags |= SE_SBNATIVE;
 653                                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 654                         }
 655                         goto out;
 656                 }
 657                 rc = -EINVAL;
 658                 pr_warn("SELinux: Unable to set superblock options "
 659                         "before the security server is initialized\n");
 660                 goto out;
 661         }
 662
 663         /*
 664          * Binary mount data FS will come through this function twice.  Once
 665          * from an explicit call and once from the generic calls from the vfs.
 666          * Since the generic VFS calls will not contain any security mount data
 667          * we need to skip the double mount verification.
 668          *
 669          * This does open a hole in which we will not notice if the first
 670          * mount using this sb set explicit options and a second mount using
 671          * this sb does not set any security options.  (The first options
 672          * will be used for both mounts)
 673          */
 674         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 675             && !opts)
 676                 goto out;
 677
 678         root_isec = backing_inode_security_novalidate(root);
 679
 680         /*
 681          * parse the mount options, check if they are valid sids.
 682          * also check if someone is trying to mount the same sb more
 683          * than once with different security options.
 684          */
 685         if (opts) {
 686                 if (opts->fscontext_sid) {
 687                         fscontext_sid = opts->fscontext_sid;
 688                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 689                                         fscontext_sid))
 690                                 goto out_double_mount;
 691                         sbsec->flags |= FSCONTEXT_MNT;
 692                 }
 693                 if (opts->context_sid) {
 694                         context_sid = opts->context_sid;
 695                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 696                                         context_sid))
 697                                 goto out_double_mount;
 698                         sbsec->flags |= CONTEXT_MNT;
 699                 }
 700                 if (opts->rootcontext_sid) {
 701                         rootcontext_sid = opts->rootcontext_sid;
 702                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 703                                         rootcontext_sid))
 704                                 goto out_double_mount;
 705                         sbsec->flags |= ROOTCONTEXT_MNT;
 706                 }
 707                 if (opts->defcontext_sid) {
 708                         defcontext_sid = opts->defcontext_sid;
 709                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 710                                         defcontext_sid))
 711                                 goto out_double_mount;
 712                         sbsec->flags |= DEFCONTEXT_MNT;
 713                 }
 714         }
 715
 716         if (sbsec->flags & SE_SBINITIALIZED) {
 717                 /* previously mounted with options, but not on this attempt? */
 718                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 719                         goto out_double_mount;
 720                 rc = 0;
 721                 goto out;
 722         }
 723
 724         if (strcmp(sb->s_type->name, "proc") == 0)
 725                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 726
 727         if (!strcmp(sb->s_type->name, "debugfs") ||
 728             !strcmp(sb->s_type->name, "tracefs") ||
 729             !strcmp(sb->s_type->name, "binder") ||
 730             !strcmp(sb->s_type->name, "bpf") ||
 731             !strcmp(sb->s_type->name, "pstore") ||
 732             !strcmp(sb->s_type->name, "securityfs"))
 733                 sbsec->flags |= SE_SBGENFS;
 734
 735         if (!strcmp(sb->s_type->name, "sysfs") ||
 736             !strcmp(sb->s_type->name, "cgroup") ||
 737             !strcmp(sb->s_type->name, "cgroup2"))
 738                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 739
 740         if (!sbsec->behavior) {
 741                 /*
 742                  * Determine the labeling behavior to use for this
 743                  * filesystem type.
 744                  */
 745                 rc = security_fs_use(sb);
 746                 if (rc) {
 747                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 748                                         __func__, sb->s_type->name, rc);
 749                         goto out;
 750                 }
 751         }
 752
 753         /*
 754          * If this is a user namespace mount and the filesystem type is not
 755          * explicitly whitelisted, then no contexts are allowed on the command
 756          * line and security labels must be ignored.
 757          */
 758         if (sb->s_user_ns != &init_user_ns &&
 759             strcmp(sb->s_type->name, "tmpfs") &&
 760             strcmp(sb->s_type->name, "ramfs") &&
 761             strcmp(sb->s_type->name, "devpts") &&
 762             strcmp(sb->s_type->name, "overlay")) {
 763                 if (context_sid || fscontext_sid || rootcontext_sid ||
 764                     defcontext_sid) {
 765                         rc = -EACCES;
 766                         goto out;
 767                 }
 768                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 769                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 770                         rc = security_transition_sid(current_sid(),
 771                                                      current_sid(),
 772                                                      SECCLASS_FILE, NULL,
 773                                                      &sbsec->mntpoint_sid);
 774                         if (rc)
 775                                 goto out;
 776                 }
 777                 goto out_set_opts;
 778         }
 779
 780         /* sets the context of the superblock for the fs being mounted. */
 781         if (fscontext_sid) {
 782                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 783                 if (rc)
 784                         goto out;
 785
 786                 sbsec->sid = fscontext_sid;
 787         }
 788
 789         /*
 790          * Switch to using mount point labeling behavior.
 791          * sets the label used on all file below the mountpoint, and will set
 792          * the superblock context if not already set.
 793          */
 794         if (sbsec->flags & SE_SBNATIVE) {
 795                 /*
 796                  * This means we are initializing a superblock that has been
 797                  * mounted before the SELinux was initialized and the
 798                  * filesystem requested native labeling. We had already
 799                  * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
 800                  * in the original mount attempt, so now we just need to set
 801                  * the SECURITY_FS_USE_NATIVE behavior.
 802                  */
 803                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 804         } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 805                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 806                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 807         }
 808
 809         if (context_sid) {
 810                 if (!fscontext_sid) {
 811                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 812                                                           cred);
 813                         if (rc)
 814                                 goto out;
 815                         sbsec->sid = context_sid;
 816                 } else {
 817                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 818                                                              cred);
 819                         if (rc)
 820                                 goto out;
 821                 }
 822                 if (!rootcontext_sid)
 823                         rootcontext_sid = context_sid;
 824
 825                 sbsec->mntpoint_sid = context_sid;
 826                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 827         }
 828
 829         if (rootcontext_sid) {
 830                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 831                                                      cred);
 832                 if (rc)
 833                         goto out;
 834
 835                 root_isec->sid = rootcontext_sid;
 836                 root_isec->initialized = LABEL_INITIALIZED;
 837         }
 838
 839         if (defcontext_sid) {
 840                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 841                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 842                         rc = -EINVAL;
 843                         pr_warn("SELinux: defcontext option is "
 844                                "invalid for this filesystem type\n");
 845                         goto out;
 846                 }
 847
 848                 if (defcontext_sid != sbsec->def_sid) {
 849                         rc = may_context_mount_inode_relabel(defcontext_sid,
 850                                                              sbsec, cred);
 851                         if (rc)
 852                                 goto out;
 853                 }
 854
 855                 sbsec->def_sid = defcontext_sid;
 856         }
 857
 858 out_set_opts:
 859         rc = sb_finish_set_opts(sb);
 860 out:
 861         mutex_unlock(&sbsec->lock);
 862         return rc;
 863 out_double_mount:
 864         rc = -EINVAL;
 865         pr_warn("SELinux: mount invalid.  Same superblock, different "
 866                "security settings for (dev %s, type %s)\n", sb->s_id,
 867                sb->s_type->name);
 868         goto out;
 869 }
 870
 871 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 872                                     const struct super_block *newsb)
 873 {
 874         struct superblock_security_struct *old = selinux_superblock(oldsb);
 875         struct superblock_security_struct *new = selinux_superblock(newsb);
 876         char oldflags = old->flags & SE_MNTMASK;
 877         char newflags = new->flags & SE_MNTMASK;
 878
 879         if (oldflags != newflags)
 880                 goto mismatch;
 881         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 882                 goto mismatch;
 883         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 884                 goto mismatch;
 885         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 886                 goto mismatch;
 887         if (oldflags & ROOTCONTEXT_MNT) {
 888                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 889                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 890                 if (oldroot->sid != newroot->sid)
 891                         goto mismatch;
 892         }
 893         return 0;
 894 mismatch:
 895         pr_warn("SELinux: mount invalid.  Same superblock, "
 896                             "different security settings for (dev %s, "
 897                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 898         return -EBUSY;
 899 }
 900
 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 902                                         struct super_block *newsb,
 903                                         unsigned long kern_flags,
 904                                         unsigned long *set_kern_flags)
 905 {
 906         int rc = 0;
 907         const struct superblock_security_struct *oldsbsec =
 908                                                 selinux_superblock(oldsb);
 909         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 910
 911         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 912         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 913         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 914
 915         /*
 916          * Specifying internal flags without providing a place to
 917          * place the results is not allowed.
 918          */
 919         if (kern_flags && !set_kern_flags)
 920                 return -EINVAL;
 921
 922         mutex_lock(&newsbsec->lock);
 923
 924         /*
 925          * if the parent was able to be mounted it clearly had no special lsm
 926          * mount options.  thus we can safely deal with this superblock later
 927          */
 928         if (!selinux_initialized()) {
 929                 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 930                         newsbsec->flags |= SE_SBNATIVE;
 931                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 932                 }
 933                 goto out;
 934         }
 935
 936         /* how can we clone if the old one wasn't set up?? */
 937         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 938
 939         /* if fs is reusing a sb, make sure that the contexts match */
 940         if (newsbsec->flags & SE_SBINITIALIZED) {
 941                 mutex_unlock(&newsbsec->lock);
 942                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 943                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 944                 return selinux_cmp_sb_context(oldsb, newsb);
 945         }
 946
 947         newsbsec->flags = oldsbsec->flags;
 948
 949         newsbsec->sid = oldsbsec->sid;
 950         newsbsec->def_sid = oldsbsec->def_sid;
 951         newsbsec->behavior = oldsbsec->behavior;
 952
 953         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 954                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 955                 rc = security_fs_use(newsb);
 956                 if (rc)
 957                         goto out;
 958         }
 959
 960         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 961                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 962                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 963         }
 964
 965         if (set_context) {
 966                 u32 sid = oldsbsec->mntpoint_sid;
 967
 968                 if (!set_fscontext)
 969                         newsbsec->sid = sid;
 970                 if (!set_rootcontext) {
 971                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 972                         newisec->sid = sid;
 973                 }
 974                 newsbsec->mntpoint_sid = sid;
 975         }
 976         if (set_rootcontext) {
 977                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 978                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 979
 980                 newisec->sid = oldisec->sid;
 981         }
 982
 983         sb_finish_set_opts(newsb);
 984 out:
 985         mutex_unlock(&newsbsec->lock);
 986         return rc;
 987 }
 988
 989 /*
 990  * NOTE: the caller is responsible for freeing the memory even if on error.
 991  */
 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 993 {
 994         struct selinux_mnt_opts *opts = *mnt_opts;
 995         u32 *dst_sid;
 996         int rc;
 997
 998         if (token == Opt_seclabel)
 999                 /* eaten and completely ignored */
1000                 return 0;
1001         if (!s)
1002                 return -EINVAL;
1003
1004         if (!selinux_initialized()) {
1005                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1006                 return -EINVAL;
1007         }
1008
1009         if (!opts) {
1010                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1011                 if (!opts)
1012                         return -ENOMEM;
1013                 *mnt_opts = opts;
1014         }
1015
1016         switch (token) {
1017         case Opt_context:
1018                 if (opts->context_sid || opts->defcontext_sid)
1019                         goto err;
1020                 dst_sid = &opts->context_sid;
1021                 break;
1022         case Opt_fscontext:
1023                 if (opts->fscontext_sid)
1024                         goto err;
1025                 dst_sid = &opts->fscontext_sid;
1026                 break;
1027         case Opt_rootcontext:
1028                 if (opts->rootcontext_sid)
1029                         goto err;
1030                 dst_sid = &opts->rootcontext_sid;
1031                 break;
1032         case Opt_defcontext:
1033                 if (opts->context_sid || opts->defcontext_sid)
1034                         goto err;
1035                 dst_sid = &opts->defcontext_sid;
1036                 break;
1037         default:
1038                 WARN_ON(1);
1039                 return -EINVAL;
1040         }
1041         rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1042         if (rc)
1043                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1044                         s, rc);
1045         return rc;
1046
1047 err:
1048         pr_warn(SEL_MOUNT_FAIL_MSG);
1049         return -EINVAL;
1050 }
1051
1052 static int show_sid(struct seq_file *m, u32 sid)
1053 {
1054         char *context = NULL;
1055         u32 len;
1056         int rc;
1057
1058         rc = security_sid_to_context(sid, &context, &len);
1059         if (!rc) {
1060                 bool has_comma = strchr(context, ',');
1061
1062                 seq_putc(m, '=');
1063                 if (has_comma)
1064                         seq_putc(m, '\"');
1065                 seq_escape(m, context, "\"\n\\");
1066                 if (has_comma)
1067                         seq_putc(m, '\"');
1068         }
1069         kfree(context);
1070         return rc;
1071 }
1072
1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1074 {
1075         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1076         int rc;
1077
1078         if (!(sbsec->flags & SE_SBINITIALIZED))
1079                 return 0;
1080
1081         if (!selinux_initialized())
1082                 return 0;
1083
1084         if (sbsec->flags & FSCONTEXT_MNT) {
1085                 seq_putc(m, ',');
1086                 seq_puts(m, FSCONTEXT_STR);
1087                 rc = show_sid(m, sbsec->sid);
1088                 if (rc)
1089                         return rc;
1090         }
1091         if (sbsec->flags & CONTEXT_MNT) {
1092                 seq_putc(m, ',');
1093                 seq_puts(m, CONTEXT_STR);
1094                 rc = show_sid(m, sbsec->mntpoint_sid);
1095                 if (rc)
1096                         return rc;
1097         }
1098         if (sbsec->flags & DEFCONTEXT_MNT) {
1099                 seq_putc(m, ',');
1100                 seq_puts(m, DEFCONTEXT_STR);
1101                 rc = show_sid(m, sbsec->def_sid);
1102                 if (rc)
1103                         return rc;
1104         }
1105         if (sbsec->flags & ROOTCONTEXT_MNT) {
1106                 struct dentry *root = sb->s_root;
1107                 struct inode_security_struct *isec = backing_inode_security(root);
1108                 seq_putc(m, ',');
1109                 seq_puts(m, ROOTCONTEXT_STR);
1110                 rc = show_sid(m, isec->sid);
1111                 if (rc)
1112                         return rc;
1113         }
1114         if (sbsec->flags & SBLABEL_MNT) {
1115                 seq_putc(m, ',');
1116                 seq_puts(m, SECLABEL_STR);
1117         }
1118         return 0;
1119 }
1120
1121 static inline u16 inode_mode_to_security_class(umode_t mode)
1122 {
1123         switch (mode & S_IFMT) {
1124         case S_IFSOCK:
1125                 return SECCLASS_SOCK_FILE;
1126         case S_IFLNK:
1127                 return SECCLASS_LNK_FILE;
1128         case S_IFREG:
1129                 return SECCLASS_FILE;
1130         case S_IFBLK:
1131                 return SECCLASS_BLK_FILE;
1132         case S_IFDIR:
1133                 return SECCLASS_DIR;
1134         case S_IFCHR:
1135                 return SECCLASS_CHR_FILE;
1136         case S_IFIFO:
1137                 return SECCLASS_FIFO_FILE;
1138
1139         }
1140
1141         return SECCLASS_FILE;
1142 }
1143
1144 static inline int default_protocol_stream(int protocol)
1145 {
1146         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1147                 protocol == IPPROTO_MPTCP);
1148 }
1149
1150 static inline int default_protocol_dgram(int protocol)
1151 {
1152         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1153 }
1154
1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1156 {
1157         bool extsockclass = selinux_policycap_extsockclass();
1158
1159         switch (family) {
1160         case PF_UNIX:
1161                 switch (type) {
1162                 case SOCK_STREAM:
1163                 case SOCK_SEQPACKET:
1164                         return SECCLASS_UNIX_STREAM_SOCKET;
1165                 case SOCK_DGRAM:
1166                 case SOCK_RAW:
1167                         return SECCLASS_UNIX_DGRAM_SOCKET;
1168                 }
1169                 break;
1170         case PF_INET:
1171         case PF_INET6:
1172                 switch (type) {
1173                 case SOCK_STREAM:
1174                 case SOCK_SEQPACKET:
1175                         if (default_protocol_stream(protocol))
1176                                 return SECCLASS_TCP_SOCKET;
1177                         else if (extsockclass && protocol == IPPROTO_SCTP)
1178                                 return SECCLASS_SCTP_SOCKET;
1179                         else
1180                                 return SECCLASS_RAWIP_SOCKET;
1181                 case SOCK_DGRAM:
1182                         if (default_protocol_dgram(protocol))
1183                                 return SECCLASS_UDP_SOCKET;
1184                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1185                                                   protocol == IPPROTO_ICMPV6))
1186                                 return SECCLASS_ICMP_SOCKET;
1187                         else
1188                                 return SECCLASS_RAWIP_SOCKET;
1189                 case SOCK_DCCP:
1190                         return SECCLASS_DCCP_SOCKET;
1191                 default:
1192                         return SECCLASS_RAWIP_SOCKET;
1193                 }
1194                 break;
1195         case PF_NETLINK:
1196                 switch (protocol) {
1197                 case NETLINK_ROUTE:
1198                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1199                 case NETLINK_SOCK_DIAG:
1200                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1201                 case NETLINK_NFLOG:
1202                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1203                 case NETLINK_XFRM:
1204                         return SECCLASS_NETLINK_XFRM_SOCKET;
1205                 case NETLINK_SELINUX:
1206                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1207                 case NETLINK_ISCSI:
1208                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1209                 case NETLINK_AUDIT:
1210                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1211                 case NETLINK_FIB_LOOKUP:
1212                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1213                 case NETLINK_CONNECTOR:
1214                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1215                 case NETLINK_NETFILTER:
1216                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1217                 case NETLINK_DNRTMSG:
1218                         return SECCLASS_NETLINK_DNRT_SOCKET;
1219                 case NETLINK_KOBJECT_UEVENT:
1220                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1221                 case NETLINK_GENERIC:
1222                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1223                 case NETLINK_SCSITRANSPORT:
1224                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1225                 case NETLINK_RDMA:
1226                         return SECCLASS_NETLINK_RDMA_SOCKET;
1227                 case NETLINK_CRYPTO:
1228                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1229                 default:
1230                         return SECCLASS_NETLINK_SOCKET;
1231                 }
1232         case PF_PACKET:
1233                 return SECCLASS_PACKET_SOCKET;
1234         case PF_KEY:
1235                 return SECCLASS_KEY_SOCKET;
1236         case PF_APPLETALK:
1237                 return SECCLASS_APPLETALK_SOCKET;
1238         }
1239
1240         if (extsockclass) {
1241                 switch (family) {
1242                 case PF_AX25:
1243                         return SECCLASS_AX25_SOCKET;
1244                 case PF_IPX:
1245                         return SECCLASS_IPX_SOCKET;
1246                 case PF_NETROM:
1247                         return SECCLASS_NETROM_SOCKET;
1248                 case PF_ATMPVC:
1249                         return SECCLASS_ATMPVC_SOCKET;
1250                 case PF_X25:
1251                         return SECCLASS_X25_SOCKET;
1252                 case PF_ROSE:
1253                         return SECCLASS_ROSE_SOCKET;
1254                 case PF_DECnet:
1255                         return SECCLASS_DECNET_SOCKET;
1256                 case PF_ATMSVC:
1257                         return SECCLASS_ATMSVC_SOCKET;
1258                 case PF_RDS:
1259                         return SECCLASS_RDS_SOCKET;
1260                 case PF_IRDA:
1261                         return SECCLASS_IRDA_SOCKET;
1262                 case PF_PPPOX:
1263                         return SECCLASS_PPPOX_SOCKET;
1264                 case PF_LLC:
1265                         return SECCLASS_LLC_SOCKET;
1266                 case PF_CAN:
1267                         return SECCLASS_CAN_SOCKET;
1268                 case PF_TIPC:
1269                         return SECCLASS_TIPC_SOCKET;
1270                 case PF_BLUETOOTH:
1271                         return SECCLASS_BLUETOOTH_SOCKET;
1272                 case PF_IUCV:
1273                         return SECCLASS_IUCV_SOCKET;
1274                 case PF_RXRPC:
1275                         return SECCLASS_RXRPC_SOCKET;
1276                 case PF_ISDN:
1277                         return SECCLASS_ISDN_SOCKET;
1278                 case PF_PHONET:
1279                         return SECCLASS_PHONET_SOCKET;
1280                 case PF_IEEE802154:
1281                         return SECCLASS_IEEE802154_SOCKET;
1282                 case PF_CAIF:
1283                         return SECCLASS_CAIF_SOCKET;
1284                 case PF_ALG:
1285                         return SECCLASS_ALG_SOCKET;
1286                 case PF_NFC:
1287                         return SECCLASS_NFC_SOCKET;
1288                 case PF_VSOCK:
1289                         return SECCLASS_VSOCK_SOCKET;
1290                 case PF_KCM:
1291                         return SECCLASS_KCM_SOCKET;
1292                 case PF_QIPCRTR:
1293                         return SECCLASS_QIPCRTR_SOCKET;
1294                 case PF_SMC:
1295                         return SECCLASS_SMC_SOCKET;
1296                 case PF_XDP:
1297                         return SECCLASS_XDP_SOCKET;
1298                 case PF_MCTP:
1299                         return SECCLASS_MCTP_SOCKET;
1300 #if PF_MAX > 46
1301 #error New address family defined, please update this function.
1302 #endif
1303                 }
1304         }
1305
1306         return SECCLASS_SOCKET;
1307 }
1308
1309 static int selinux_genfs_get_sid(struct dentry *dentry,
1310                                  u16 tclass,
1311                                  u16 flags,
1312                                  u32 *sid)
1313 {
1314         int rc;
1315         struct super_block *sb = dentry->d_sb;
1316         char *buffer, *path;
1317
1318         buffer = (char *)__get_free_page(GFP_KERNEL);
1319         if (!buffer)
1320                 return -ENOMEM;
1321
1322         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1323         if (IS_ERR(path))
1324                 rc = PTR_ERR(path);
1325         else {
1326                 if (flags & SE_SBPROC) {
1327                         /* each process gets a /proc/PID/ entry. Strip off the
1328                          * PID part to get a valid selinux labeling.
1329                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1330                         while (path[1] >= '0' && path[1] <= '9') {
1331                                 path[1] = '/';
1332                                 path++;
1333                         }
1334                 }
1335                 rc = security_genfs_sid(sb->s_type->name,
1336                                         path, tclass, sid);
1337                 if (rc == -ENOENT) {
1338                         /* No match in policy, mark as unlabeled. */
1339                         *sid = SECINITSID_UNLABELED;
1340                         rc = 0;
1341                 }
1342         }
1343         free_page((unsigned long)buffer);
1344         return rc;
1345 }
1346
1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1348                                   u32 def_sid, u32 *sid)
1349 {
1350 #define INITCONTEXTLEN 255
1351         char *context;
1352         unsigned int len;
1353         int rc;
1354
1355         len = INITCONTEXTLEN;
1356         context = kmalloc(len + 1, GFP_NOFS);
1357         if (!context)
1358                 return -ENOMEM;
1359
1360         context[len] = '\0';
1361         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1362         if (rc == -ERANGE) {
1363                 kfree(context);
1364
1365                 /* Need a larger buffer.  Query for the right size. */
1366                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1367                 if (rc < 0)
1368                         return rc;
1369
1370                 len = rc;
1371                 context = kmalloc(len + 1, GFP_NOFS);
1372                 if (!context)
1373                         return -ENOMEM;
1374
1375                 context[len] = '\0';
1376                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1377                                     context, len);
1378         }
1379         if (rc < 0) {
1380                 kfree(context);
1381                 if (rc != -ENODATA) {
1382                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1383                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1384                         return rc;
1385                 }
1386                 *sid = def_sid;
1387                 return 0;
1388         }
1389
1390         rc = security_context_to_sid_default(context, rc, sid,
1391                                              def_sid, GFP_NOFS);
1392         if (rc) {
1393                 char *dev = inode->i_sb->s_id;
1394                 unsigned long ino = inode->i_ino;
1395
1396                 if (rc == -EINVAL) {
1397                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1398                                               ino, dev, context);
1399                 } else {
1400                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1401                                 __func__, context, -rc, dev, ino);
1402                 }
1403         }
1404         kfree(context);
1405         return 0;
1406 }
1407
1408 /* The inode's security attributes must be initialized before first use. */
1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1410 {
1411         struct superblock_security_struct *sbsec = NULL;
1412         struct inode_security_struct *isec = selinux_inode(inode);
1413         u32 task_sid, sid = 0;
1414         u16 sclass;
1415         struct dentry *dentry;
1416         int rc = 0;
1417
1418         if (isec->initialized == LABEL_INITIALIZED)
1419                 return 0;
1420
1421         spin_lock(&isec->lock);
1422         if (isec->initialized == LABEL_INITIALIZED)
1423                 goto out_unlock;
1424
1425         if (isec->sclass == SECCLASS_FILE)
1426                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1427
1428         sbsec = selinux_superblock(inode->i_sb);
1429         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1430                 /* Defer initialization until selinux_complete_init,
1431                    after the initial policy is loaded and the security
1432                    server is ready to handle calls. */
1433                 spin_lock(&sbsec->isec_lock);
1434                 if (list_empty(&isec->list))
1435                         list_add(&isec->list, &sbsec->isec_head);
1436                 spin_unlock(&sbsec->isec_lock);
1437                 goto out_unlock;
1438         }
1439
1440         sclass = isec->sclass;
1441         task_sid = isec->task_sid;
1442         sid = isec->sid;
1443         isec->initialized = LABEL_PENDING;
1444         spin_unlock(&isec->lock);
1445
1446         switch (sbsec->behavior) {
1447         /*
1448          * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1449          * via xattr when called from delayed_superblock_init().
1450          */
1451         case SECURITY_FS_USE_NATIVE:
1452         case SECURITY_FS_USE_XATTR:
1453                 if (!(inode->i_opflags & IOP_XATTR)) {
1454                         sid = sbsec->def_sid;
1455                         break;
1456                 }
1457                 /* Need a dentry, since the xattr API requires one.
1458                    Life would be simpler if we could just pass the inode. */
1459                 if (opt_dentry) {
1460                         /* Called from d_instantiate or d_splice_alias. */
1461                         dentry = dget(opt_dentry);
1462                 } else {
1463                         /*
1464                          * Called from selinux_complete_init, try to find a dentry.
1465                          * Some filesystems really want a connected one, so try
1466                          * that first.  We could split SECURITY_FS_USE_XATTR in
1467                          * two, depending upon that...
1468                          */
1469                         dentry = d_find_alias(inode);
1470                         if (!dentry)
1471                                 dentry = d_find_any_alias(inode);
1472                 }
1473                 if (!dentry) {
1474                         /*
1475                          * this is can be hit on boot when a file is accessed
1476                          * before the policy is loaded.  When we load policy we
1477                          * may find inodes that have no dentry on the
1478                          * sbsec->isec_head list.  No reason to complain as these
1479                          * will get fixed up the next time we go through
1480                          * inode_doinit with a dentry, before these inodes could
1481                          * be used again by userspace.
1482                          */
1483                         goto out_invalid;
1484                 }
1485
1486                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1487                                             &sid);
1488                 dput(dentry);
1489                 if (rc)
1490                         goto out;
1491                 break;
1492         case SECURITY_FS_USE_TASK:
1493                 sid = task_sid;
1494                 break;
1495         case SECURITY_FS_USE_TRANS:
1496                 /* Default to the fs SID. */
1497                 sid = sbsec->sid;
1498
1499                 /* Try to obtain a transition SID. */
1500                 rc = security_transition_sid(task_sid, sid,
1501                                              sclass, NULL, &sid);
1502                 if (rc)
1503                         goto out;
1504                 break;
1505         case SECURITY_FS_USE_MNTPOINT:
1506                 sid = sbsec->mntpoint_sid;
1507                 break;
1508         default:
1509                 /* Default to the fs superblock SID. */
1510                 sid = sbsec->sid;
1511
1512                 if ((sbsec->flags & SE_SBGENFS) &&
1513                      (!S_ISLNK(inode->i_mode) ||
1514                       selinux_policycap_genfs_seclabel_symlinks())) {
1515                         /* We must have a dentry to determine the label on
1516                          * procfs inodes */
1517                         if (opt_dentry) {
1518                                 /* Called from d_instantiate or
1519                                  * d_splice_alias. */
1520                                 dentry = dget(opt_dentry);
1521                         } else {
1522                                 /* Called from selinux_complete_init, try to
1523                                  * find a dentry.  Some filesystems really want
1524                                  * a connected one, so try that first.
1525                                  */
1526                                 dentry = d_find_alias(inode);
1527                                 if (!dentry)
1528                                         dentry = d_find_any_alias(inode);
1529                         }
1530                         /*
1531                          * This can be hit on boot when a file is accessed
1532                          * before the policy is loaded.  When we load policy we
1533                          * may find inodes that have no dentry on the
1534                          * sbsec->isec_head list.  No reason to complain as
1535                          * these will get fixed up the next time we go through
1536                          * inode_doinit() with a dentry, before these inodes
1537                          * could be used again by userspace.
1538                          */
1539                         if (!dentry)
1540                                 goto out_invalid;
1541                         rc = selinux_genfs_get_sid(dentry, sclass,
1542                                                    sbsec->flags, &sid);
1543                         if (rc) {
1544                                 dput(dentry);
1545                                 goto out;
1546                         }
1547
1548                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1549                             (inode->i_opflags & IOP_XATTR)) {
1550                                 rc = inode_doinit_use_xattr(inode, dentry,
1551                                                             sid, &sid);
1552                                 if (rc) {
1553                                         dput(dentry);
1554                                         goto out;
1555                                 }
1556                         }
1557                         dput(dentry);
1558                 }
1559                 break;
1560         }
1561
1562 out:
1563         spin_lock(&isec->lock);
1564         if (isec->initialized == LABEL_PENDING) {
1565                 if (rc) {
1566                         isec->initialized = LABEL_INVALID;
1567                         goto out_unlock;
1568                 }
1569                 isec->initialized = LABEL_INITIALIZED;
1570                 isec->sid = sid;
1571         }
1572
1573 out_unlock:
1574         spin_unlock(&isec->lock);
1575         return rc;
1576
1577 out_invalid:
1578         spin_lock(&isec->lock);
1579         if (isec->initialized == LABEL_PENDING) {
1580                 isec->initialized = LABEL_INVALID;
1581                 isec->sid = sid;
1582         }
1583         spin_unlock(&isec->lock);
1584         return 0;
1585 }
1586
1587 /* Convert a Linux signal to an access vector. */
1588 static inline u32 signal_to_av(int sig)
1589 {
1590         u32 perm = 0;
1591
1592         switch (sig) {
1593         case SIGCHLD:
1594                 /* Commonly granted from child to parent. */
1595                 perm = PROCESS__SIGCHLD;
1596                 break;
1597         case SIGKILL:
1598                 /* Cannot be caught or ignored */
1599                 perm = PROCESS__SIGKILL;
1600                 break;
1601         case SIGSTOP:
1602                 /* Cannot be caught or ignored */
1603                 perm = PROCESS__SIGSTOP;
1604                 break;
1605         default:
1606                 /* All other signals. */
1607                 perm = PROCESS__SIGNAL;
1608                 break;
1609         }
1610
1611         return perm;
1612 }
1613
1614 #if CAP_LAST_CAP > 63
1615 #error Fix SELinux to handle capabilities > 63.
1616 #endif
1617
1618 /* Check whether a task is allowed to use a capability. */
1619 static int cred_has_capability(const struct cred *cred,
1620                                int cap, unsigned int opts, bool initns)
1621 {
1622         struct common_audit_data ad;
1623         struct av_decision avd;
1624         u16 sclass;
1625         u32 sid = cred_sid(cred);
1626         u32 av = CAP_TO_MASK(cap);
1627         int rc;
1628
1629         ad.type = LSM_AUDIT_DATA_CAP;
1630         ad.u.cap = cap;
1631
1632         switch (CAP_TO_INDEX(cap)) {
1633         case 0:
1634                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1635                 break;
1636         case 1:
1637                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1638                 break;
1639         default:
1640                 pr_err("SELinux:  out of range capability %d\n", cap);
1641                 BUG();
1642                 return -EINVAL;
1643         }
1644
1645         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1646         if (!(opts & CAP_OPT_NOAUDIT)) {
1647                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1648                 if (rc2)
1649                         return rc2;
1650         }
1651         return rc;
1652 }
1653
1654 /* Check whether a task has a particular permission to an inode.
1655    The 'adp' parameter is optional and allows other audit
1656    data to be passed (e.g. the dentry). */
1657 static int inode_has_perm(const struct cred *cred,
1658                           struct inode *inode,
1659                           u32 perms,
1660                           struct common_audit_data *adp)
1661 {
1662         struct inode_security_struct *isec;
1663         u32 sid;
1664
1665         if (unlikely(IS_PRIVATE(inode)))
1666                 return 0;
1667
1668         sid = cred_sid(cred);
1669         isec = selinux_inode(inode);
1670
1671         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1672 }
1673
1674 /* Same as inode_has_perm, but pass explicit audit data containing
1675    the dentry to help the auditing code to more easily generate the
1676    pathname if needed. */
1677 static inline int dentry_has_perm(const struct cred *cred,
1678                                   struct dentry *dentry,
1679                                   u32 av)
1680 {
1681         struct inode *inode = d_backing_inode(dentry);
1682         struct common_audit_data ad;
1683
1684         ad.type = LSM_AUDIT_DATA_DENTRY;
1685         ad.u.dentry = dentry;
1686         __inode_security_revalidate(inode, dentry, true);
1687         return inode_has_perm(cred, inode, av, &ad);
1688 }
1689
1690 /* Same as inode_has_perm, but pass explicit audit data containing
1691    the path to help the auditing code to more easily generate the
1692    pathname if needed. */
1693 static inline int path_has_perm(const struct cred *cred,
1694                                 const struct path *path,
1695                                 u32 av)
1696 {
1697         struct inode *inode = d_backing_inode(path->dentry);
1698         struct common_audit_data ad;
1699
1700         ad.type = LSM_AUDIT_DATA_PATH;
1701         ad.u.path = *path;
1702         __inode_security_revalidate(inode, path->dentry, true);
1703         return inode_has_perm(cred, inode, av, &ad);
1704 }
1705
1706 /* Same as path_has_perm, but uses the inode from the file struct. */
1707 static inline int file_path_has_perm(const struct cred *cred,
1708                                      struct file *file,
1709                                      u32 av)
1710 {
1711         struct common_audit_data ad;
1712
1713         ad.type = LSM_AUDIT_DATA_FILE;
1714         ad.u.file = file;
1715         return inode_has_perm(cred, file_inode(file), av, &ad);
1716 }
1717
1718 #ifdef CONFIG_BPF_SYSCALL
1719 static int bpf_fd_pass(const struct file *file, u32 sid);
1720 #endif
1721
1722 /* Check whether a task can use an open file descriptor to
1723    access an inode in a given way.  Check access to the
1724    descriptor itself, and then use dentry_has_perm to
1725    check a particular permission to the file.
1726    Access to the descriptor is implicitly granted if it
1727    has the same SID as the process.  If av is zero, then
1728    access to the file is not checked, e.g. for cases
1729    where only the descriptor is affected like seek. */
1730 static int file_has_perm(const struct cred *cred,
1731                          struct file *file,
1732                          u32 av)
1733 {
1734         struct file_security_struct *fsec = selinux_file(file);
1735         struct inode *inode = file_inode(file);
1736         struct common_audit_data ad;
1737         u32 sid = cred_sid(cred);
1738         int rc;
1739
1740         ad.type = LSM_AUDIT_DATA_FILE;
1741         ad.u.file = file;
1742
1743         if (sid != fsec->sid) {
1744                 rc = avc_has_perm(sid, fsec->sid,
1745                                   SECCLASS_FD,
1746                                   FD__USE,
1747                                   &ad);
1748                 if (rc)
1749                         goto out;
1750         }
1751
1752 #ifdef CONFIG_BPF_SYSCALL
1753         rc = bpf_fd_pass(file, cred_sid(cred));
1754         if (rc)
1755                 return rc;
1756 #endif
1757
1758         /* av is zero if only checking access to the descriptor. */
1759         rc = 0;
1760         if (av)
1761                 rc = inode_has_perm(cred, inode, av, &ad);
1762
1763 out:
1764         return rc;
1765 }
1766
1767 /*
1768  * Determine the label for an inode that might be unioned.
1769  */
1770 static int
1771 selinux_determine_inode_label(const struct task_security_struct *tsec,
1772                                  struct inode *dir,
1773                                  const struct qstr *name, u16 tclass,
1774                                  u32 *_new_isid)
1775 {
1776         const struct superblock_security_struct *sbsec =
1777                                                 selinux_superblock(dir->i_sb);
1778
1779         if ((sbsec->flags & SE_SBINITIALIZED) &&
1780             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1781                 *_new_isid = sbsec->mntpoint_sid;
1782         } else if ((sbsec->flags & SBLABEL_MNT) &&
1783                    tsec->create_sid) {
1784                 *_new_isid = tsec->create_sid;
1785         } else {
1786                 const struct inode_security_struct *dsec = inode_security(dir);
1787                 return security_transition_sid(tsec->sid,
1788                                                dsec->sid, tclass,
1789                                                name, _new_isid);
1790         }
1791
1792         return 0;
1793 }
1794
1795 /* Check whether a task can create a file. */
1796 static int may_create(struct inode *dir,
1797                       struct dentry *dentry,
1798                       u16 tclass)
1799 {
1800         const struct task_security_struct *tsec = selinux_cred(current_cred());
1801         struct inode_security_struct *dsec;
1802         struct superblock_security_struct *sbsec;
1803         u32 sid, newsid;
1804         struct common_audit_data ad;
1805         int rc;
1806
1807         dsec = inode_security(dir);
1808         sbsec = selinux_superblock(dir->i_sb);
1809
1810         sid = tsec->sid;
1811
1812         ad.type = LSM_AUDIT_DATA_DENTRY;
1813         ad.u.dentry = dentry;
1814
1815         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1816                           DIR__ADD_NAME | DIR__SEARCH,
1817                           &ad);
1818         if (rc)
1819                 return rc;
1820
1821         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1822                                            &newsid);
1823         if (rc)
1824                 return rc;
1825
1826         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1827         if (rc)
1828                 return rc;
1829
1830         return avc_has_perm(newsid, sbsec->sid,
1831                             SECCLASS_FILESYSTEM,
1832                             FILESYSTEM__ASSOCIATE, &ad);
1833 }
1834
1835 #define MAY_LINK        0
1836 #define MAY_UNLINK      1
1837 #define MAY_RMDIR       2
1838
1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1840 static int may_link(struct inode *dir,
1841                     struct dentry *dentry,
1842                     int kind)
1843
1844 {
1845         struct inode_security_struct *dsec, *isec;
1846         struct common_audit_data ad;
1847         u32 sid = current_sid();
1848         u32 av;
1849         int rc;
1850
1851         dsec = inode_security(dir);
1852         isec = backing_inode_security(dentry);
1853
1854         ad.type = LSM_AUDIT_DATA_DENTRY;
1855         ad.u.dentry = dentry;
1856
1857         av = DIR__SEARCH;
1858         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1859         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1860         if (rc)
1861                 return rc;
1862
1863         switch (kind) {
1864         case MAY_LINK:
1865                 av = FILE__LINK;
1866                 break;
1867         case MAY_UNLINK:
1868                 av = FILE__UNLINK;
1869                 break;
1870         case MAY_RMDIR:
1871                 av = DIR__RMDIR;
1872                 break;
1873         default:
1874                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1875                         __func__, kind);
1876                 return 0;
1877         }
1878
1879         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1880         return rc;
1881 }
1882
1883 static inline int may_rename(struct inode *old_dir,
1884                              struct dentry *old_dentry,
1885                              struct inode *new_dir,
1886                              struct dentry *new_dentry)
1887 {
1888         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1889         struct common_audit_data ad;
1890         u32 sid = current_sid();
1891         u32 av;
1892         int old_is_dir, new_is_dir;
1893         int rc;
1894
1895         old_dsec = inode_security(old_dir);
1896         old_isec = backing_inode_security(old_dentry);
1897         old_is_dir = d_is_dir(old_dentry);
1898         new_dsec = inode_security(new_dir);
1899
1900         ad.type = LSM_AUDIT_DATA_DENTRY;
1901
1902         ad.u.dentry = old_dentry;
1903         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1904                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1905         if (rc)
1906                 return rc;
1907         rc = avc_has_perm(sid, old_isec->sid,
1908                           old_isec->sclass, FILE__RENAME, &ad);
1909         if (rc)
1910                 return rc;
1911         if (old_is_dir && new_dir != old_dir) {
1912                 rc = avc_has_perm(sid, old_isec->sid,
1913                                   old_isec->sclass, DIR__REPARENT, &ad);
1914                 if (rc)
1915                         return rc;
1916         }
1917
1918         ad.u.dentry = new_dentry;
1919         av = DIR__ADD_NAME | DIR__SEARCH;
1920         if (d_is_positive(new_dentry))
1921                 av |= DIR__REMOVE_NAME;
1922         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1923         if (rc)
1924                 return rc;
1925         if (d_is_positive(new_dentry)) {
1926                 new_isec = backing_inode_security(new_dentry);
1927                 new_is_dir = d_is_dir(new_dentry);
1928                 rc = avc_has_perm(sid, new_isec->sid,
1929                                   new_isec->sclass,
1930                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1931                 if (rc)
1932                         return rc;
1933         }
1934
1935         return 0;
1936 }
1937
1938 /* Check whether a task can perform a filesystem operation. */
1939 static int superblock_has_perm(const struct cred *cred,
1940                                const struct super_block *sb,
1941                                u32 perms,
1942                                struct common_audit_data *ad)
1943 {
1944         struct superblock_security_struct *sbsec;
1945         u32 sid = cred_sid(cred);
1946
1947         sbsec = selinux_superblock(sb);
1948         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1949 }
1950
1951 /* Convert a Linux mode and permission mask to an access vector. */
1952 static inline u32 file_mask_to_av(int mode, int mask)
1953 {
1954         u32 av = 0;
1955
1956         if (!S_ISDIR(mode)) {
1957                 if (mask & MAY_EXEC)
1958                         av |= FILE__EXECUTE;
1959                 if (mask & MAY_READ)
1960                         av |= FILE__READ;
1961
1962                 if (mask & MAY_APPEND)
1963                         av |= FILE__APPEND;
1964                 else if (mask & MAY_WRITE)
1965                         av |= FILE__WRITE;
1966
1967         } else {
1968                 if (mask & MAY_EXEC)
1969                         av |= DIR__SEARCH;
1970                 if (mask & MAY_WRITE)
1971                         av |= DIR__WRITE;
1972                 if (mask & MAY_READ)
1973                         av |= DIR__READ;
1974         }
1975
1976         return av;
1977 }
1978
1979 /* Convert a Linux file to an access vector. */
1980 static inline u32 file_to_av(const struct file *file)
1981 {
1982         u32 av = 0;
1983
1984         if (file->f_mode & FMODE_READ)
1985                 av |= FILE__READ;
1986         if (file->f_mode & FMODE_WRITE) {
1987                 if (file->f_flags & O_APPEND)
1988                         av |= FILE__APPEND;
1989                 else
1990                         av |= FILE__WRITE;
1991         }
1992         if (!av) {
1993                 /*
1994                  * Special file opened with flags 3 for ioctl-only use.
1995                  */
1996                 av = FILE__IOCTL;
1997         }
1998
1999         return av;
2000 }
2001
2002 /*
2003  * Convert a file to an access vector and include the correct
2004  * open permission.
2005  */
2006 static inline u32 open_file_to_av(struct file *file)
2007 {
2008         u32 av = file_to_av(file);
2009         struct inode *inode = file_inode(file);
2010
2011         if (selinux_policycap_openperm() &&
2012             inode->i_sb->s_magic != SOCKFS_MAGIC)
2013                 av |= FILE__OPEN;
2014
2015         return av;
2016 }
2017
2018 /* Hook functions begin here. */
2019
2020 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2021 {
2022         return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2023                             BINDER__SET_CONTEXT_MGR, NULL);
2024 }
2025
2026 static int selinux_binder_transaction(const struct cred *from,
2027                                       const struct cred *to)
2028 {
2029         u32 mysid = current_sid();
2030         u32 fromsid = cred_sid(from);
2031         u32 tosid = cred_sid(to);
2032         int rc;
2033
2034         if (mysid != fromsid) {
2035                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2036                                   BINDER__IMPERSONATE, NULL);
2037                 if (rc)
2038                         return rc;
2039         }
2040
2041         return avc_has_perm(fromsid, tosid,
2042                             SECCLASS_BINDER, BINDER__CALL, NULL);
2043 }
2044
2045 static int selinux_binder_transfer_binder(const struct cred *from,
2046                                           const struct cred *to)
2047 {
2048         return avc_has_perm(cred_sid(from), cred_sid(to),
2049                             SECCLASS_BINDER, BINDER__TRANSFER,
2050                             NULL);
2051 }
2052
2053 static int selinux_binder_transfer_file(const struct cred *from,
2054                                         const struct cred *to,
2055                                         const struct file *file)
2056 {
2057         u32 sid = cred_sid(to);
2058         struct file_security_struct *fsec = selinux_file(file);
2059         struct dentry *dentry = file->f_path.dentry;
2060         struct inode_security_struct *isec;
2061         struct common_audit_data ad;
2062         int rc;
2063
2064         ad.type = LSM_AUDIT_DATA_PATH;
2065         ad.u.path = file->f_path;
2066
2067         if (sid != fsec->sid) {
2068                 rc = avc_has_perm(sid, fsec->sid,
2069                                   SECCLASS_FD,
2070                                   FD__USE,
2071                                   &ad);
2072                 if (rc)
2073                         return rc;
2074         }
2075
2076 #ifdef CONFIG_BPF_SYSCALL
2077         rc = bpf_fd_pass(file, sid);
2078         if (rc)
2079                 return rc;
2080 #endif
2081
2082         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2083                 return 0;
2084
2085         isec = backing_inode_security(dentry);
2086         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2087                             &ad);
2088 }
2089
2090 static int selinux_ptrace_access_check(struct task_struct *child,
2091                                        unsigned int mode)
2092 {
2093         u32 sid = current_sid();
2094         u32 csid = task_sid_obj(child);
2095
2096         if (mode & PTRACE_MODE_READ)
2097                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2098                                 NULL);
2099
2100         return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2101                         NULL);
2102 }
2103
2104 static int selinux_ptrace_traceme(struct task_struct *parent)
2105 {
2106         return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2107                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2108 }
2109
2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2111                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2112 {
2113         return avc_has_perm(current_sid(), task_sid_obj(target),
2114                         SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2115 }
2116
2117 static int selinux_capset(struct cred *new, const struct cred *old,
2118                           const kernel_cap_t *effective,
2119                           const kernel_cap_t *inheritable,
2120                           const kernel_cap_t *permitted)
2121 {
2122         return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2123                             PROCESS__SETCAP, NULL);
2124 }
2125
2126 /*
2127  * (This comment used to live with the selinux_task_setuid hook,
2128  * which was removed).
2129  *
2130  * Since setuid only affects the current process, and since the SELinux
2131  * controls are not based on the Linux identity attributes, SELinux does not
2132  * need to control this operation.  However, SELinux does control the use of
2133  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2134  */
2135
2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2137                            int cap, unsigned int opts)
2138 {
2139         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2140 }
2141
2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2143 {
2144         const struct cred *cred = current_cred();
2145         int rc = 0;
2146
2147         if (!sb)
2148                 return 0;
2149
2150         switch (cmds) {
2151         case Q_SYNC:
2152         case Q_QUOTAON:
2153         case Q_QUOTAOFF:
2154         case Q_SETINFO:
2155         case Q_SETQUOTA:
2156         case Q_XQUOTAOFF:
2157         case Q_XQUOTAON:
2158         case Q_XSETQLIM:
2159                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2160                 break;
2161         case Q_GETFMT:
2162         case Q_GETINFO:
2163         case Q_GETQUOTA:
2164         case Q_XGETQUOTA:
2165         case Q_XGETQSTAT:
2166         case Q_XGETQSTATV:
2167         case Q_XGETNEXTQUOTA:
2168                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2169                 break;
2170         default:
2171                 rc = 0;  /* let the kernel handle invalid cmds */
2172                 break;
2173         }
2174         return rc;
2175 }
2176
2177 static int selinux_quota_on(struct dentry *dentry)
2178 {
2179         const struct cred *cred = current_cred();
2180
2181         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2182 }
2183
2184 static int selinux_syslog(int type)
2185 {
2186         switch (type) {
2187         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2188         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2189                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2190                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2191         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2192         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2193         /* Set level of messages printed to console */
2194         case SYSLOG_ACTION_CONSOLE_LEVEL:
2195                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2196                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2197                                     NULL);
2198         }
2199         /* All other syslog types */
2200         return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2202 }
2203
2204 /*
2205  * Check that a process has enough memory to allocate a new virtual
2206  * mapping. 0 means there is enough memory for the allocation to
2207  * succeed and -ENOMEM implies there is not.
2208  *
2209  * Do not audit the selinux permission check, as this is applied to all
2210  * processes that allocate mappings.
2211  */
2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2213 {
2214         int rc, cap_sys_admin = 0;
2215
2216         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2217                                  CAP_OPT_NOAUDIT, true);
2218         if (rc == 0)
2219                 cap_sys_admin = 1;
2220
2221         return cap_sys_admin;
2222 }
2223
2224 /* binprm security operations */
2225
2226 static u32 ptrace_parent_sid(void)
2227 {
2228         u32 sid = 0;
2229         struct task_struct *tracer;
2230
2231         rcu_read_lock();
2232         tracer = ptrace_parent(current);
2233         if (tracer)
2234                 sid = task_sid_obj(tracer);
2235         rcu_read_unlock();
2236
2237         return sid;
2238 }
2239
2240 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2241                             const struct task_security_struct *old_tsec,
2242                             const struct task_security_struct *new_tsec)
2243 {
2244         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2245         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2246         int rc;
2247         u32 av;
2248
2249         if (!nnp && !nosuid)
2250                 return 0; /* neither NNP nor nosuid */
2251
2252         if (new_tsec->sid == old_tsec->sid)
2253                 return 0; /* No change in credentials */
2254
2255         /*
2256          * If the policy enables the nnp_nosuid_transition policy capability,
2257          * then we permit transitions under NNP or nosuid if the
2258          * policy allows the corresponding permission between
2259          * the old and new contexts.
2260          */
2261         if (selinux_policycap_nnp_nosuid_transition()) {
2262                 av = 0;
2263                 if (nnp)
2264                         av |= PROCESS2__NNP_TRANSITION;
2265                 if (nosuid)
2266                         av |= PROCESS2__NOSUID_TRANSITION;
2267                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2268                                   SECCLASS_PROCESS2, av, NULL);
2269                 if (!rc)
2270                         return 0;
2271         }
2272
2273         /*
2274          * We also permit NNP or nosuid transitions to bounded SIDs,
2275          * i.e. SIDs that are guaranteed to only be allowed a subset
2276          * of the permissions of the current SID.
2277          */
2278         rc = security_bounded_transition(old_tsec->sid,
2279                                          new_tsec->sid);
2280         if (!rc)
2281                 return 0;
2282
2283         /*
2284          * On failure, preserve the errno values for NNP vs nosuid.
2285          * NNP:  Operation not permitted for caller.
2286          * nosuid:  Permission denied to file.
2287          */
2288         if (nnp)
2289                 return -EPERM;
2290         return -EACCES;
2291 }
2292
2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2294 {
2295         const struct task_security_struct *old_tsec;
2296         struct task_security_struct *new_tsec;
2297         struct inode_security_struct *isec;
2298         struct common_audit_data ad;
2299         struct inode *inode = file_inode(bprm->file);
2300         int rc;
2301
2302         /* SELinux context only depends on initial program or script and not
2303          * the script interpreter */
2304
2305         old_tsec = selinux_cred(current_cred());
2306         new_tsec = selinux_cred(bprm->cred);
2307         isec = inode_security(inode);
2308
2309         /* Default to the current task SID. */
2310         new_tsec->sid = old_tsec->sid;
2311         new_tsec->osid = old_tsec->sid;
2312
2313         /* Reset fs, key, and sock SIDs on execve. */
2314         new_tsec->create_sid = 0;
2315         new_tsec->keycreate_sid = 0;
2316         new_tsec->sockcreate_sid = 0;
2317
2318         /*
2319          * Before policy is loaded, label any task outside kernel space
2320          * as SECINITSID_INIT, so that any userspace tasks surviving from
2321          * early boot end up with a label different from SECINITSID_KERNEL
2322          * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2323          */
2324         if (!selinux_initialized()) {
2325                 new_tsec->sid = SECINITSID_INIT;
2326                 /* also clear the exec_sid just in case */
2327                 new_tsec->exec_sid = 0;
2328                 return 0;
2329         }
2330
2331         if (old_tsec->exec_sid) {
2332                 new_tsec->sid = old_tsec->exec_sid;
2333                 /* Reset exec SID on execve. */
2334                 new_tsec->exec_sid = 0;
2335
2336                 /* Fail on NNP or nosuid if not an allowed transition. */
2337                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2338                 if (rc)
2339                         return rc;
2340         } else {
2341                 /* Check for a default transition on this program. */
2342                 rc = security_transition_sid(old_tsec->sid,
2343                                              isec->sid, SECCLASS_PROCESS, NULL,
2344                                              &new_tsec->sid);
2345                 if (rc)
2346                         return rc;
2347
2348                 /*
2349                  * Fallback to old SID on NNP or nosuid if not an allowed
2350                  * transition.
2351                  */
2352                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2353                 if (rc)
2354                         new_tsec->sid = old_tsec->sid;
2355         }
2356
2357         ad.type = LSM_AUDIT_DATA_FILE;
2358         ad.u.file = bprm->file;
2359
2360         if (new_tsec->sid == old_tsec->sid) {
2361                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2362                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2363                 if (rc)
2364                         return rc;
2365         } else {
2366                 /* Check permissions for the transition. */
2367                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2368                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2369                 if (rc)
2370                         return rc;
2371
2372                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2373                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2374                 if (rc)
2375                         return rc;
2376
2377                 /* Check for shared state */
2378                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2379                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2380                                           SECCLASS_PROCESS, PROCESS__SHARE,
2381                                           NULL);
2382                         if (rc)
2383                                 return -EPERM;
2384                 }
2385
2386                 /* Make sure that anyone attempting to ptrace over a task that
2387                  * changes its SID has the appropriate permit */
2388                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2389                         u32 ptsid = ptrace_parent_sid();
2390                         if (ptsid != 0) {
2391                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2392                                                   SECCLASS_PROCESS,
2393                                                   PROCESS__PTRACE, NULL);
2394                                 if (rc)
2395                                         return -EPERM;
2396                         }
2397                 }
2398
2399                 /* Clear any possibly unsafe personality bits on exec: */
2400                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2401
2402                 /* Enable secure mode for SIDs transitions unless
2403                    the noatsecure permission is granted between
2404                    the two SIDs, i.e. ahp returns 0. */
2405                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2406                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2407                                   NULL);
2408                 bprm->secureexec |= !!rc;
2409         }
2410
2411         return 0;
2412 }
2413
2414 static int match_file(const void *p, struct file *file, unsigned fd)
2415 {
2416         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2417 }
2418
2419 /* Derived from fs/exec.c:flush_old_files. */
2420 static inline void flush_unauthorized_files(const struct cred *cred,
2421                                             struct files_struct *files)
2422 {
2423         struct file *file, *devnull = NULL;
2424         struct tty_struct *tty;
2425         int drop_tty = 0;
2426         unsigned n;
2427
2428         tty = get_current_tty();
2429         if (tty) {
2430                 spin_lock(&tty->files_lock);
2431                 if (!list_empty(&tty->tty_files)) {
2432                         struct tty_file_private *file_priv;
2433
2434                         /* Revalidate access to controlling tty.
2435                            Use file_path_has_perm on the tty path directly
2436                            rather than using file_has_perm, as this particular
2437                            open file may belong to another process and we are
2438                            only interested in the inode-based check here. */
2439                         file_priv = list_first_entry(&tty->tty_files,
2440                                                 struct tty_file_private, list);
2441                         file = file_priv->file;
2442                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2443                                 drop_tty = 1;
2444                 }
2445                 spin_unlock(&tty->files_lock);
2446                 tty_kref_put(tty);
2447         }
2448         /* Reset controlling tty. */
2449         if (drop_tty)
2450                 no_tty();
2451
2452         /* Revalidate access to inherited open files. */
2453         n = iterate_fd(files, 0, match_file, cred);
2454         if (!n) /* none found? */
2455                 return;
2456
2457         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2458         if (IS_ERR(devnull))
2459                 devnull = NULL;
2460         /* replace all the matching ones with this */
2461         do {
2462                 replace_fd(n - 1, devnull, 0);
2463         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2464         if (devnull)
2465                 fput(devnull);
2466 }
2467
2468 /*
2469  * Prepare a process for imminent new credential changes due to exec
2470  */
2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2472 {
2473         struct task_security_struct *new_tsec;
2474         struct rlimit *rlim, *initrlim;
2475         int rc, i;
2476
2477         new_tsec = selinux_cred(bprm->cred);
2478         if (new_tsec->sid == new_tsec->osid)
2479                 return;
2480
2481         /* Close files for which the new task SID is not authorized. */
2482         flush_unauthorized_files(bprm->cred, current->files);
2483
2484         /* Always clear parent death signal on SID transitions. */
2485         current->pdeath_signal = 0;
2486
2487         /* Check whether the new SID can inherit resource limits from the old
2488          * SID.  If not, reset all soft limits to the lower of the current
2489          * task's hard limit and the init task's soft limit.
2490          *
2491          * Note that the setting of hard limits (even to lower them) can be
2492          * controlled by the setrlimit check.  The inclusion of the init task's
2493          * soft limit into the computation is to avoid resetting soft limits
2494          * higher than the default soft limit for cases where the default is
2495          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2496          */
2497         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2498                           PROCESS__RLIMITINH, NULL);
2499         if (rc) {
2500                 /* protect against do_prlimit() */
2501                 task_lock(current);
2502                 for (i = 0; i < RLIM_NLIMITS; i++) {
2503                         rlim = current->signal->rlim + i;
2504                         initrlim = init_task.signal->rlim + i;
2505                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2506                 }
2507                 task_unlock(current);
2508                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2509                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2510         }
2511 }
2512
2513 /*
2514  * Clean up the process immediately after the installation of new credentials
2515  * due to exec
2516  */
2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2518 {
2519         const struct task_security_struct *tsec = selinux_cred(current_cred());
2520         u32 osid, sid;
2521         int rc;
2522
2523         osid = tsec->osid;
2524         sid = tsec->sid;
2525
2526         if (sid == osid)
2527                 return;
2528
2529         /* Check whether the new SID can inherit signal state from the old SID.
2530          * If not, clear itimers to avoid subsequent signal generation and
2531          * flush and unblock signals.
2532          *
2533          * This must occur _after_ the task SID has been updated so that any
2534          * kill done after the flush will be checked against the new SID.
2535          */
2536         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2537         if (rc) {
2538                 clear_itimer();
2539
2540                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2541                 if (!fatal_signal_pending(current)) {
2542                         flush_sigqueue(&current->pending);
2543                         flush_sigqueue(&current->signal->shared_pending);
2544                         flush_signal_handlers(current, 1);
2545                         sigemptyset(&current->blocked);
2546                         recalc_sigpending();
2547                 }
2548                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2549         }
2550
2551         /* Wake up the parent if it is waiting so that it can recheck
2552          * wait permission to the new task SID. */
2553         read_lock(&tasklist_lock);
2554         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2555         read_unlock(&tasklist_lock);
2556 }
2557
2558 /* superblock security operations */
2559
2560 static int selinux_sb_alloc_security(struct super_block *sb)
2561 {
2562         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2563
2564         mutex_init(&sbsec->lock);
2565         INIT_LIST_HEAD(&sbsec->isec_head);
2566         spin_lock_init(&sbsec->isec_lock);
2567         sbsec->sid = SECINITSID_UNLABELED;
2568         sbsec->def_sid = SECINITSID_FILE;
2569         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2570
2571         return 0;
2572 }
2573
2574 static inline int opt_len(const char *s)
2575 {
2576         bool open_quote = false;
2577         int len;
2578         char c;
2579
2580         for (len = 0; (c = s[len]) != '\0'; len++) {
2581                 if (c == '"')
2582                         open_quote = !open_quote;
2583                 if (c == ',' && !open_quote)
2584                         break;
2585         }
2586         return len;
2587 }
2588
2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2590 {
2591         char *from = options;
2592         char *to = options;
2593         bool first = true;
2594         int rc;
2595
2596         while (1) {
2597                 int len = opt_len(from);
2598                 int token;
2599                 char *arg = NULL;
2600
2601                 token = match_opt_prefix(from, len, &arg);
2602
2603                 if (token != Opt_error) {
2604                         char *p, *q;
2605
2606                         /* strip quotes */
2607                         if (arg) {
2608                                 for (p = q = arg; p < from + len; p++) {
2609                                         char c = *p;
2610                                         if (c != '"')
2611                                                 *q++ = c;
2612                                 }
2613                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2614                                 if (!arg) {
2615                                         rc = -ENOMEM;
2616                                         goto free_opt;
2617                                 }
2618                         }
2619                         rc = selinux_add_opt(token, arg, mnt_opts);
2620                         kfree(arg);
2621                         arg = NULL;
2622                         if (unlikely(rc)) {
2623                                 goto free_opt;
2624                         }
2625                 } else {
2626                         if (!first) {   // copy with preceding comma
2627                                 from--;
2628                                 len++;
2629                         }
2630                         if (to != from)
2631                                 memmove(to, from, len);
2632                         to += len;
2633                         first = false;
2634                 }
2635                 if (!from[len])
2636                         break;
2637                 from += len + 1;
2638         }
2639         *to = '\0';
2640         return 0;
2641
2642 free_opt:
2643         if (*mnt_opts) {
2644                 selinux_free_mnt_opts(*mnt_opts);
2645                 *mnt_opts = NULL;
2646         }
2647         return rc;
2648 }
2649
2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2651 {
2652         struct selinux_mnt_opts *opts = mnt_opts;
2653         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2654
2655         /*
2656          * Superblock not initialized (i.e. no options) - reject if any
2657          * options specified, otherwise accept.
2658          */
2659         if (!(sbsec->flags & SE_SBINITIALIZED))
2660                 return opts ? 1 : 0;
2661
2662         /*
2663          * Superblock initialized and no options specified - reject if
2664          * superblock has any options set, otherwise accept.
2665          */
2666         if (!opts)
2667                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2668
2669         if (opts->fscontext_sid) {
2670                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2671                                opts->fscontext_sid))
2672                         return 1;
2673         }
2674         if (opts->context_sid) {
2675                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2676                                opts->context_sid))
2677                         return 1;
2678         }
2679         if (opts->rootcontext_sid) {
2680                 struct inode_security_struct *root_isec;
2681
2682                 root_isec = backing_inode_security(sb->s_root);
2683                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2684                                opts->rootcontext_sid))
2685                         return 1;
2686         }
2687         if (opts->defcontext_sid) {
2688                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2689                                opts->defcontext_sid))
2690                         return 1;
2691         }
2692         return 0;
2693 }
2694
2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2696 {
2697         struct selinux_mnt_opts *opts = mnt_opts;
2698         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2699
2700         if (!(sbsec->flags & SE_SBINITIALIZED))
2701                 return 0;
2702
2703         if (!opts)
2704                 return 0;
2705
2706         if (opts->fscontext_sid) {
2707                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2708                                opts->fscontext_sid))
2709                         goto out_bad_option;
2710         }
2711         if (opts->context_sid) {
2712                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2713                                opts->context_sid))
2714                         goto out_bad_option;
2715         }
2716         if (opts->rootcontext_sid) {
2717                 struct inode_security_struct *root_isec;
2718                 root_isec = backing_inode_security(sb->s_root);
2719                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2720                                opts->rootcontext_sid))
2721                         goto out_bad_option;
2722         }
2723         if (opts->defcontext_sid) {
2724                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2725                                opts->defcontext_sid))
2726                         goto out_bad_option;
2727         }
2728         return 0;
2729
2730 out_bad_option:
2731         pr_warn("SELinux: unable to change security options "
2732                "during remount (dev %s, type=%s)\n", sb->s_id,
2733                sb->s_type->name);
2734         return -EINVAL;
2735 }
2736
2737 static int selinux_sb_kern_mount(const struct super_block *sb)
2738 {
2739         const struct cred *cred = current_cred();
2740         struct common_audit_data ad;
2741
2742         ad.type = LSM_AUDIT_DATA_DENTRY;
2743         ad.u.dentry = sb->s_root;
2744         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2745 }
2746
2747 static int selinux_sb_statfs(struct dentry *dentry)
2748 {
2749         const struct cred *cred = current_cred();
2750         struct common_audit_data ad;
2751
2752         ad.type = LSM_AUDIT_DATA_DENTRY;
2753         ad.u.dentry = dentry->d_sb->s_root;
2754         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2755 }
2756
2757 static int selinux_mount(const char *dev_name,
2758                          const struct path *path,
2759                          const char *type,
2760                          unsigned long flags,
2761                          void *data)
2762 {
2763         const struct cred *cred = current_cred();
2764
2765         if (flags & MS_REMOUNT)
2766                 return superblock_has_perm(cred, path->dentry->d_sb,
2767                                            FILESYSTEM__REMOUNT, NULL);
2768         else
2769                 return path_has_perm(cred, path, FILE__MOUNTON);
2770 }
2771
2772 static int selinux_move_mount(const struct path *from_path,
2773                               const struct path *to_path)
2774 {
2775         const struct cred *cred = current_cred();
2776
2777         return path_has_perm(cred, to_path, FILE__MOUNTON);
2778 }
2779
2780 static int selinux_umount(struct vfsmount *mnt, int flags)
2781 {
2782         const struct cred *cred = current_cred();
2783
2784         return superblock_has_perm(cred, mnt->mnt_sb,
2785                                    FILESYSTEM__UNMOUNT, NULL);
2786 }
2787
2788 static int selinux_fs_context_submount(struct fs_context *fc,
2789                                    struct super_block *reference)
2790 {
2791         const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2792         struct selinux_mnt_opts *opts;
2793
2794         /*
2795          * Ensure that fc->security remains NULL when no options are set
2796          * as expected by selinux_set_mnt_opts().
2797          */
2798         if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2799                 return 0;
2800
2801         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2802         if (!opts)
2803                 return -ENOMEM;
2804
2805         if (sbsec->flags & FSCONTEXT_MNT)
2806                 opts->fscontext_sid = sbsec->sid;
2807         if (sbsec->flags & CONTEXT_MNT)
2808                 opts->context_sid = sbsec->mntpoint_sid;
2809         if (sbsec->flags & DEFCONTEXT_MNT)
2810                 opts->defcontext_sid = sbsec->def_sid;
2811         fc->security = opts;
2812         return 0;
2813 }
2814
2815 static int selinux_fs_context_dup(struct fs_context *fc,
2816                                   struct fs_context *src_fc)
2817 {
2818         const struct selinux_mnt_opts *src = src_fc->security;
2819
2820         if (!src)
2821                 return 0;
2822
2823         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2824         return fc->security ? 0 : -ENOMEM;
2825 }
2826
2827 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2828         fsparam_string(CONTEXT_STR,     Opt_context),
2829         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2830         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2831         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2832         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2833         {}
2834 };
2835
2836 static int selinux_fs_context_parse_param(struct fs_context *fc,
2837                                           struct fs_parameter *param)
2838 {
2839         struct fs_parse_result result;
2840         int opt;
2841
2842         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2843         if (opt < 0)
2844                 return opt;
2845
2846         return selinux_add_opt(opt, param->string, &fc->security);
2847 }
2848
2849 /* inode security operations */
2850
2851 static int selinux_inode_alloc_security(struct inode *inode)
2852 {
2853         struct inode_security_struct *isec = selinux_inode(inode);
2854         u32 sid = current_sid();
2855
2856         spin_lock_init(&isec->lock);
2857         INIT_LIST_HEAD(&isec->list);
2858         isec->inode = inode;
2859         isec->sid = SECINITSID_UNLABELED;
2860         isec->sclass = SECCLASS_FILE;
2861         isec->task_sid = sid;
2862         isec->initialized = LABEL_INVALID;
2863
2864         return 0;
2865 }
2866
2867 static void selinux_inode_free_security(struct inode *inode)
2868 {
2869         inode_free_security(inode);
2870 }
2871
2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2873                                         const struct qstr *name,
2874                                         const char **xattr_name, void **ctx,
2875                                         u32 *ctxlen)
2876 {
2877         u32 newsid;
2878         int rc;
2879
2880         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2881                                            d_inode(dentry->d_parent), name,
2882                                            inode_mode_to_security_class(mode),
2883                                            &newsid);
2884         if (rc)
2885                 return rc;
2886
2887         if (xattr_name)
2888                 *xattr_name = XATTR_NAME_SELINUX;
2889
2890         return security_sid_to_context(newsid, (char **)ctx,
2891                                        ctxlen);
2892 }
2893
2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2895                                           struct qstr *name,
2896                                           const struct cred *old,
2897                                           struct cred *new)
2898 {
2899         u32 newsid;
2900         int rc;
2901         struct task_security_struct *tsec;
2902
2903         rc = selinux_determine_inode_label(selinux_cred(old),
2904                                            d_inode(dentry->d_parent), name,
2905                                            inode_mode_to_security_class(mode),
2906                                            &newsid);
2907         if (rc)
2908                 return rc;
2909
2910         tsec = selinux_cred(new);
2911         tsec->create_sid = newsid;
2912         return 0;
2913 }
2914
2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2916                                        const struct qstr *qstr,
2917                                        struct xattr *xattrs, int *xattr_count)
2918 {
2919         const struct task_security_struct *tsec = selinux_cred(current_cred());
2920         struct superblock_security_struct *sbsec;
2921         struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2922         u32 newsid, clen;
2923         int rc;
2924         char *context;
2925
2926         sbsec = selinux_superblock(dir->i_sb);
2927
2928         newsid = tsec->create_sid;
2929
2930         rc = selinux_determine_inode_label(tsec, dir, qstr,
2931                 inode_mode_to_security_class(inode->i_mode),
2932                 &newsid);
2933         if (rc)
2934                 return rc;
2935
2936         /* Possibly defer initialization to selinux_complete_init. */
2937         if (sbsec->flags & SE_SBINITIALIZED) {
2938                 struct inode_security_struct *isec = selinux_inode(inode);
2939                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2940                 isec->sid = newsid;
2941                 isec->initialized = LABEL_INITIALIZED;
2942         }
2943
2944         if (!selinux_initialized() ||
2945             !(sbsec->flags & SBLABEL_MNT))
2946                 return -EOPNOTSUPP;
2947
2948         if (xattr) {
2949                 rc = security_sid_to_context_force(newsid,
2950                                                    &context, &clen);
2951                 if (rc)
2952                         return rc;
2953                 xattr->value = context;
2954                 xattr->value_len = clen;
2955                 xattr->name = XATTR_SELINUX_SUFFIX;
2956         }
2957
2958         return 0;
2959 }
2960
2961 static int selinux_inode_init_security_anon(struct inode *inode,
2962                                             const struct qstr *name,
2963                                             const struct inode *context_inode)
2964 {
2965         const struct task_security_struct *tsec = selinux_cred(current_cred());
2966         struct common_audit_data ad;
2967         struct inode_security_struct *isec;
2968         int rc;
2969
2970         if (unlikely(!selinux_initialized()))
2971                 return 0;
2972
2973         isec = selinux_inode(inode);
2974
2975         /*
2976          * We only get here once per ephemeral inode.  The inode has
2977          * been initialized via inode_alloc_security but is otherwise
2978          * untouched.
2979          */
2980
2981         if (context_inode) {
2982                 struct inode_security_struct *context_isec =
2983                         selinux_inode(context_inode);
2984                 if (context_isec->initialized != LABEL_INITIALIZED) {
2985                         pr_err("SELinux:  context_inode is not initialized\n");
2986                         return -EACCES;
2987                 }
2988
2989                 isec->sclass = context_isec->sclass;
2990                 isec->sid = context_isec->sid;
2991         } else {
2992                 isec->sclass = SECCLASS_ANON_INODE;
2993                 rc = security_transition_sid(
2994                         tsec->sid, tsec->sid,
2995                         isec->sclass, name, &isec->sid);
2996                 if (rc)
2997                         return rc;
2998         }
2999
3000         isec->initialized = LABEL_INITIALIZED;
3001         /*
3002          * Now that we've initialized security, check whether we're
3003          * allowed to actually create this type of anonymous inode.
3004          */
3005
3006         ad.type = LSM_AUDIT_DATA_ANONINODE;
3007         ad.u.anonclass = name ? (const char *)name->name : "?";
3008
3009         return avc_has_perm(tsec->sid,
3010                             isec->sid,
3011                             isec->sclass,
3012                             FILE__CREATE,
3013                             &ad);
3014 }
3015
3016 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3017 {
3018         return may_create(dir, dentry, SECCLASS_FILE);
3019 }
3020
3021 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3022 {
3023         return may_link(dir, old_dentry, MAY_LINK);
3024 }
3025
3026 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3027 {
3028         return may_link(dir, dentry, MAY_UNLINK);
3029 }
3030
3031 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3032 {
3033         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3034 }
3035
3036 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3037 {
3038         return may_create(dir, dentry, SECCLASS_DIR);
3039 }
3040
3041 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3042 {
3043         return may_link(dir, dentry, MAY_RMDIR);
3044 }
3045
3046 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3047 {
3048         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3049 }
3050
3051 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3052                                 struct inode *new_inode, struct dentry *new_dentry)
3053 {
3054         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3055 }
3056
3057 static int selinux_inode_readlink(struct dentry *dentry)
3058 {
3059         const struct cred *cred = current_cred();
3060
3061         return dentry_has_perm(cred, dentry, FILE__READ);
3062 }
3063
3064 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3065                                      bool rcu)
3066 {
3067         const struct cred *cred = current_cred();
3068         struct common_audit_data ad;
3069         struct inode_security_struct *isec;
3070         u32 sid;
3071
3072         ad.type = LSM_AUDIT_DATA_DENTRY;
3073         ad.u.dentry = dentry;
3074         sid = cred_sid(cred);
3075         isec = inode_security_rcu(inode, rcu);
3076         if (IS_ERR(isec))
3077                 return PTR_ERR(isec);
3078
3079         return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3080 }
3081
3082 static noinline int audit_inode_permission(struct inode *inode,
3083                                            u32 perms, u32 audited, u32 denied,
3084                                            int result)
3085 {
3086         struct common_audit_data ad;
3087         struct inode_security_struct *isec = selinux_inode(inode);
3088
3089         ad.type = LSM_AUDIT_DATA_INODE;
3090         ad.u.inode = inode;
3091
3092         return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3093                             audited, denied, result, &ad);
3094 }
3095
3096 static int selinux_inode_permission(struct inode *inode, int mask)
3097 {
3098         const struct cred *cred = current_cred();
3099         u32 perms;
3100         bool from_access;
3101         bool no_block = mask & MAY_NOT_BLOCK;
3102         struct inode_security_struct *isec;
3103         u32 sid;
3104         struct av_decision avd;
3105         int rc, rc2;
3106         u32 audited, denied;
3107
3108         from_access = mask & MAY_ACCESS;
3109         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3110
3111         /* No permission to check.  Existence test. */
3112         if (!mask)
3113                 return 0;
3114
3115         if (unlikely(IS_PRIVATE(inode)))
3116                 return 0;
3117
3118         perms = file_mask_to_av(inode->i_mode, mask);
3119
3120         sid = cred_sid(cred);
3121         isec = inode_security_rcu(inode, no_block);
3122         if (IS_ERR(isec))
3123                 return PTR_ERR(isec);
3124
3125         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3126                                   &avd);
3127         audited = avc_audit_required(perms, &avd, rc,
3128                                      from_access ? FILE__AUDIT_ACCESS : 0,
3129                                      &denied);
3130         if (likely(!audited))
3131                 return rc;
3132
3133         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3134         if (rc2)
3135                 return rc2;
3136         return rc;
3137 }
3138
3139 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3140 {
3141         const struct cred *cred = current_cred();
3142         struct inode *inode = d_backing_inode(dentry);
3143         unsigned int ia_valid = iattr->ia_valid;
3144         __u32 av = FILE__WRITE;
3145
3146         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3147         if (ia_valid & ATTR_FORCE) {
3148                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3149                               ATTR_FORCE);
3150                 if (!ia_valid)
3151                         return 0;
3152         }
3153
3154         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3155                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3156                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3157
3158         if (selinux_policycap_openperm() &&
3159             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3160             (ia_valid & ATTR_SIZE) &&
3161             !(ia_valid & ATTR_FILE))
3162                 av |= FILE__OPEN;
3163
3164         return dentry_has_perm(cred, dentry, av);
3165 }
3166
3167 static int selinux_inode_getattr(const struct path *path)
3168 {
3169         return path_has_perm(current_cred(), path, FILE__GETATTR);
3170 }
3171
3172 static bool has_cap_mac_admin(bool audit)
3173 {
3174         const struct cred *cred = current_cred();
3175         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3176
3177         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3178                 return false;
3179         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3180                 return false;
3181         return true;
3182 }
3183
3184 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3185                                   struct dentry *dentry, const char *name,
3186                                   const void *value, size_t size, int flags)
3187 {
3188         struct inode *inode = d_backing_inode(dentry);
3189         struct inode_security_struct *isec;
3190         struct superblock_security_struct *sbsec;
3191         struct common_audit_data ad;
3192         u32 newsid, sid = current_sid();
3193         int rc = 0;
3194
3195         if (strcmp(name, XATTR_NAME_SELINUX)) {
3196                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3197                 if (rc)
3198                         return rc;
3199
3200                 /* Not an attribute we recognize, so just check the
3201                    ordinary setattr permission. */
3202                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3203         }
3204
3205         if (!selinux_initialized())
3206                 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3207
3208         sbsec = selinux_superblock(inode->i_sb);
3209         if (!(sbsec->flags & SBLABEL_MNT))
3210                 return -EOPNOTSUPP;
3211
3212         if (!inode_owner_or_capable(idmap, inode))
3213                 return -EPERM;
3214
3215         ad.type = LSM_AUDIT_DATA_DENTRY;
3216         ad.u.dentry = dentry;
3217
3218         isec = backing_inode_security(dentry);
3219         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3220                           FILE__RELABELFROM, &ad);
3221         if (rc)
3222                 return rc;
3223
3224         rc = security_context_to_sid(value, size, &newsid,
3225                                      GFP_KERNEL);
3226         if (rc == -EINVAL) {
3227                 if (!has_cap_mac_admin(true)) {
3228                         struct audit_buffer *ab;
3229                         size_t audit_size;
3230
3231                         /* We strip a nul only if it is at the end, otherwise the
3232                          * context contains a nul and we should audit that */
3233                         if (value) {
3234                                 const char *str = value;
3235
3236                                 if (str[size - 1] == '\0')
3237                                         audit_size = size - 1;
3238                                 else
3239                                         audit_size = size;
3240                         } else {
3241                                 audit_size = 0;
3242                         }
3243                         ab = audit_log_start(audit_context(),
3244                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3245                         if (!ab)
3246                                 return rc;
3247                         audit_log_format(ab, "op=setxattr invalid_context=");
3248                         audit_log_n_untrustedstring(ab, value, audit_size);
3249                         audit_log_end(ab);
3250
3251                         return rc;
3252                 }
3253                 rc = security_context_to_sid_force(value,
3254                                                    size, &newsid);
3255         }
3256         if (rc)
3257                 return rc;
3258
3259         rc = avc_has_perm(sid, newsid, isec->sclass,
3260                           FILE__RELABELTO, &ad);
3261         if (rc)
3262                 return rc;
3263
3264         rc = security_validate_transition(isec->sid, newsid,
3265                                           sid, isec->sclass);
3266         if (rc)
3267                 return rc;
3268
3269         return avc_has_perm(newsid,
3270                             sbsec->sid,
3271                             SECCLASS_FILESYSTEM,
3272                             FILESYSTEM__ASSOCIATE,
3273                             &ad);
3274 }
3275
3276 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3277                                  struct dentry *dentry, const char *acl_name,
3278                                  struct posix_acl *kacl)
3279 {
3280         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3281 }
3282
3283 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3284                                  struct dentry *dentry, const char *acl_name)
3285 {
3286         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3287 }
3288
3289 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3290                                     struct dentry *dentry, const char *acl_name)
3291 {
3292         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3293 }
3294
3295 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3296                                         const void *value, size_t size,
3297                                         int flags)
3298 {
3299         struct inode *inode = d_backing_inode(dentry);
3300         struct inode_security_struct *isec;
3301         u32 newsid;
3302         int rc;
3303
3304         if (strcmp(name, XATTR_NAME_SELINUX)) {
3305                 /* Not an attribute we recognize, so nothing to do. */
3306                 return;
3307         }
3308
3309         if (!selinux_initialized()) {
3310                 /* If we haven't even been initialized, then we can't validate
3311                  * against a policy, so leave the label as invalid. It may
3312                  * resolve to a valid label on the next revalidation try if
3313                  * we've since initialized.
3314                  */
3315                 return;
3316         }
3317
3318         rc = security_context_to_sid_force(value, size,
3319                                            &newsid);
3320         if (rc) {
3321                 pr_err("SELinux:  unable to map context to SID"
3322                        "for (%s, %lu), rc=%d\n",
3323                        inode->i_sb->s_id, inode->i_ino, -rc);
3324                 return;
3325         }
3326
3327         isec = backing_inode_security(dentry);
3328         spin_lock(&isec->lock);
3329         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3330         isec->sid = newsid;
3331         isec->initialized = LABEL_INITIALIZED;
3332         spin_unlock(&isec->lock);
3333 }
3334
3335 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3336 {
3337         const struct cred *cred = current_cred();
3338
3339         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3340 }
3341
3342 static int selinux_inode_listxattr(struct dentry *dentry)
3343 {
3344         const struct cred *cred = current_cred();
3345
3346         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3347 }
3348
3349 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3350                                      struct dentry *dentry, const char *name)
3351 {
3352         if (strcmp(name, XATTR_NAME_SELINUX)) {
3353                 int rc = cap_inode_removexattr(idmap, dentry, name);
3354                 if (rc)
3355                         return rc;
3356
3357                 /* Not an attribute we recognize, so just check the
3358                    ordinary setattr permission. */
3359                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360         }
3361
3362         if (!selinux_initialized())
3363                 return 0;
3364
3365         /* No one is allowed to remove a SELinux security label.
3366            You can change the label, but all data must be labeled. */
3367         return -EACCES;
3368 }
3369
3370 static int selinux_path_notify(const struct path *path, u64 mask,
3371                                                 unsigned int obj_type)
3372 {
3373         int ret;
3374         u32 perm;
3375
3376         struct common_audit_data ad;
3377
3378         ad.type = LSM_AUDIT_DATA_PATH;
3379         ad.u.path = *path;
3380
3381         /*
3382          * Set permission needed based on the type of mark being set.
3383          * Performs an additional check for sb watches.
3384          */
3385         switch (obj_type) {
3386         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3387                 perm = FILE__WATCH_MOUNT;
3388                 break;
3389         case FSNOTIFY_OBJ_TYPE_SB:
3390                 perm = FILE__WATCH_SB;
3391                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3392                                                 FILESYSTEM__WATCH, &ad);
3393                 if (ret)
3394                         return ret;
3395                 break;
3396         case FSNOTIFY_OBJ_TYPE_INODE:
3397                 perm = FILE__WATCH;
3398                 break;
3399         default:
3400                 return -EINVAL;
3401         }
3402
3403         /* blocking watches require the file:watch_with_perm permission */
3404         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3405                 perm |= FILE__WATCH_WITH_PERM;
3406
3407         /* watches on read-like events need the file:watch_reads permission */
3408         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3409                 perm |= FILE__WATCH_READS;
3410
3411         return path_has_perm(current_cred(), path, perm);
3412 }
3413
3414 /*
3415  * Copy the inode security context value to the user.
3416  *
3417  * Permission check is handled by selinux_inode_getxattr hook.
3418  */
3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420                                      struct inode *inode, const char *name,
3421                                      void **buffer, bool alloc)
3422 {
3423         u32 size;
3424         int error;
3425         char *context = NULL;
3426         struct inode_security_struct *isec;
3427
3428         /*
3429          * If we're not initialized yet, then we can't validate contexts, so
3430          * just let vfs_getxattr fall back to using the on-disk xattr.
3431          */
3432         if (!selinux_initialized() ||
3433             strcmp(name, XATTR_SELINUX_SUFFIX))
3434                 return -EOPNOTSUPP;
3435
3436         /*
3437          * If the caller has CAP_MAC_ADMIN, then get the raw context
3438          * value even if it is not defined by current policy; otherwise,
3439          * use the in-core value under current policy.
3440          * Use the non-auditing forms of the permission checks since
3441          * getxattr may be called by unprivileged processes commonly
3442          * and lack of permission just means that we fall back to the
3443          * in-core context value, not a denial.
3444          */
3445         isec = inode_security(inode);
3446         if (has_cap_mac_admin(false))
3447                 error = security_sid_to_context_force(isec->sid, &context,
3448                                                       &size);
3449         else
3450                 error = security_sid_to_context(isec->sid,
3451                                                 &context, &size);
3452         if (error)
3453                 return error;
3454         error = size;
3455         if (alloc) {
3456                 *buffer = context;
3457                 goto out_nofree;
3458         }
3459         kfree(context);
3460 out_nofree:
3461         return error;
3462 }
3463
3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465                                      const void *value, size_t size, int flags)
3466 {
3467         struct inode_security_struct *isec = inode_security_novalidate(inode);
3468         struct superblock_security_struct *sbsec;
3469         u32 newsid;
3470         int rc;
3471
3472         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473                 return -EOPNOTSUPP;
3474
3475         sbsec = selinux_superblock(inode->i_sb);
3476         if (!(sbsec->flags & SBLABEL_MNT))
3477                 return -EOPNOTSUPP;
3478
3479         if (!value || !size)
3480                 return -EACCES;
3481
3482         rc = security_context_to_sid(value, size, &newsid,
3483                                      GFP_KERNEL);
3484         if (rc)
3485                 return rc;
3486
3487         spin_lock(&isec->lock);
3488         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489         isec->sid = newsid;
3490         isec->initialized = LABEL_INITIALIZED;
3491         spin_unlock(&isec->lock);
3492         return 0;
3493 }
3494
3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496 {
3497         const int len = sizeof(XATTR_NAME_SELINUX);
3498
3499         if (!selinux_initialized())
3500                 return 0;
3501
3502         if (buffer && len <= buffer_size)
3503                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3504         return len;
3505 }
3506
3507 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3508 {
3509         struct inode_security_struct *isec = inode_security_novalidate(inode);
3510         *secid = isec->sid;
3511 }
3512
3513 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514 {
3515         u32 sid;
3516         struct task_security_struct *tsec;
3517         struct cred *new_creds = *new;
3518
3519         if (new_creds == NULL) {
3520                 new_creds = prepare_creds();
3521                 if (!new_creds)
3522                         return -ENOMEM;
3523         }
3524
3525         tsec = selinux_cred(new_creds);
3526         /* Get label from overlay inode and set it in create_sid */
3527         selinux_inode_getsecid(d_inode(src), &sid);
3528         tsec->create_sid = sid;
3529         *new = new_creds;
3530         return 0;
3531 }
3532
3533 static int selinux_inode_copy_up_xattr(const char *name)
3534 {
3535         /* The copy_up hook above sets the initial context on an inode, but we
3536          * don't then want to overwrite it by blindly copying all the lower
3537          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3538          */
3539         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3540                 return 1; /* Discard */
3541         /*
3542          * Any other attribute apart from SELINUX is not claimed, supported
3543          * by selinux.
3544          */
3545         return -EOPNOTSUPP;
3546 }
3547
3548 /* kernfs node operations */
3549
3550 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3551                                         struct kernfs_node *kn)
3552 {
3553         const struct task_security_struct *tsec = selinux_cred(current_cred());
3554         u32 parent_sid, newsid, clen;
3555         int rc;
3556         char *context;
3557
3558         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3559         if (rc == -ENODATA)
3560                 return 0;
3561         else if (rc < 0)
3562                 return rc;
3563
3564         clen = (u32)rc;
3565         context = kmalloc(clen, GFP_KERNEL);
3566         if (!context)
3567                 return -ENOMEM;
3568
3569         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3570         if (rc < 0) {
3571                 kfree(context);
3572                 return rc;
3573         }
3574
3575         rc = security_context_to_sid(context, clen, &parent_sid,
3576                                      GFP_KERNEL);
3577         kfree(context);
3578         if (rc)
3579                 return rc;
3580
3581         if (tsec->create_sid) {
3582                 newsid = tsec->create_sid;
3583         } else {
3584                 u16 secclass = inode_mode_to_security_class(kn->mode);
3585                 struct qstr q;
3586
3587                 q.name = kn->name;
3588                 q.hash_len = hashlen_string(kn_dir, kn->name);
3589
3590                 rc = security_transition_sid(tsec->sid,
3591                                              parent_sid, secclass, &q,
3592                                              &newsid);
3593                 if (rc)
3594                         return rc;
3595         }
3596
3597         rc = security_sid_to_context_force(newsid,
3598                                            &context, &clen);
3599         if (rc)
3600                 return rc;
3601
3602         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3603                               XATTR_CREATE);
3604         kfree(context);
3605         return rc;
3606 }
3607
3608
3609 /* file security operations */
3610
3611 static int selinux_revalidate_file_permission(struct file *file, int mask)
3612 {
3613         const struct cred *cred = current_cred();
3614         struct inode *inode = file_inode(file);
3615
3616         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3617         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3618                 mask |= MAY_APPEND;
3619
3620         return file_has_perm(cred, file,
3621                              file_mask_to_av(inode->i_mode, mask));
3622 }
3623
3624 static int selinux_file_permission(struct file *file, int mask)
3625 {
3626         struct inode *inode = file_inode(file);
3627         struct file_security_struct *fsec = selinux_file(file);
3628         struct inode_security_struct *isec;
3629         u32 sid = current_sid();
3630
3631         if (!mask)
3632                 /* No permission to check.  Existence test. */
3633                 return 0;
3634
3635         isec = inode_security(inode);
3636         if (sid == fsec->sid && fsec->isid == isec->sid &&
3637             fsec->pseqno == avc_policy_seqno())
3638                 /* No change since file_open check. */
3639                 return 0;
3640
3641         return selinux_revalidate_file_permission(file, mask);
3642 }
3643
3644 static int selinux_file_alloc_security(struct file *file)
3645 {
3646         struct file_security_struct *fsec = selinux_file(file);
3647         u32 sid = current_sid();
3648
3649         fsec->sid = sid;
3650         fsec->fown_sid = sid;
3651
3652         return 0;
3653 }
3654
3655 /*
3656  * Check whether a task has the ioctl permission and cmd
3657  * operation to an inode.
3658  */
3659 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3660                 u32 requested, u16 cmd)
3661 {
3662         struct common_audit_data ad;
3663         struct file_security_struct *fsec = selinux_file(file);
3664         struct inode *inode = file_inode(file);
3665         struct inode_security_struct *isec;
3666         struct lsm_ioctlop_audit ioctl;
3667         u32 ssid = cred_sid(cred);
3668         int rc;
3669         u8 driver = cmd >> 8;
3670         u8 xperm = cmd & 0xff;
3671
3672         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3673         ad.u.op = &ioctl;
3674         ad.u.op->cmd = cmd;
3675         ad.u.op->path = file->f_path;
3676
3677         if (ssid != fsec->sid) {
3678                 rc = avc_has_perm(ssid, fsec->sid,
3679                                 SECCLASS_FD,
3680                                 FD__USE,
3681                                 &ad);
3682                 if (rc)
3683                         goto out;
3684         }
3685
3686         if (unlikely(IS_PRIVATE(inode)))
3687                 return 0;
3688
3689         isec = inode_security(inode);
3690         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3691                                     requested, driver, xperm, &ad);
3692 out:
3693         return rc;
3694 }
3695
3696 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3697                               unsigned long arg)
3698 {
3699         const struct cred *cred = current_cred();
3700         int error = 0;
3701
3702         switch (cmd) {
3703         case FIONREAD:
3704         case FIBMAP:
3705         case FIGETBSZ:
3706         case FS_IOC_GETFLAGS:
3707         case FS_IOC_GETVERSION:
3708                 error = file_has_perm(cred, file, FILE__GETATTR);
3709                 break;
3710
3711         case FS_IOC_SETFLAGS:
3712         case FS_IOC_SETVERSION:
3713                 error = file_has_perm(cred, file, FILE__SETATTR);
3714                 break;
3715
3716         /* sys_ioctl() checks */
3717         case FIONBIO:
3718         case FIOASYNC:
3719                 error = file_has_perm(cred, file, 0);
3720                 break;
3721
3722         case KDSKBENT:
3723         case KDSKBSENT:
3724                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3725                                             CAP_OPT_NONE, true);
3726                 break;
3727
3728         case FIOCLEX:
3729         case FIONCLEX:
3730                 if (!selinux_policycap_ioctl_skip_cloexec())
3731                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3732                 break;
3733
3734         /* default case assumes that the command will go
3735          * to the file's ioctl() function.
3736          */
3737         default:
3738                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3739         }
3740         return error;
3741 }
3742
3743 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3744                               unsigned long arg)
3745 {
3746         /*
3747          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3748          * make sure we don't compare 32-bit flags to 64-bit flags.
3749          */
3750         switch (cmd) {
3751         case FS_IOC32_GETFLAGS:
3752                 cmd = FS_IOC_GETFLAGS;
3753                 break;
3754         case FS_IOC32_SETFLAGS:
3755                 cmd = FS_IOC_SETFLAGS;
3756                 break;
3757         case FS_IOC32_GETVERSION:
3758                 cmd = FS_IOC_GETVERSION;
3759                 break;
3760         case FS_IOC32_SETVERSION:
3761                 cmd = FS_IOC_SETVERSION;
3762                 break;
3763         default:
3764                 break;
3765         }
3766
3767         return selinux_file_ioctl(file, cmd, arg);
3768 }
3769
3770 static int default_noexec __ro_after_init;
3771
3772 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3773 {
3774         const struct cred *cred = current_cred();
3775         u32 sid = cred_sid(cred);
3776         int rc = 0;
3777
3778         if (default_noexec &&
3779             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3780                                    (!shared && (prot & PROT_WRITE)))) {
3781                 /*
3782                  * We are making executable an anonymous mapping or a
3783                  * private file mapping that will also be writable.
3784                  * This has an additional check.
3785                  */
3786                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3787                                   PROCESS__EXECMEM, NULL);
3788                 if (rc)
3789                         goto error;
3790         }
3791
3792         if (file) {
3793                 /* read access is always possible with a mapping */
3794                 u32 av = FILE__READ;
3795
3796                 /* write access only matters if the mapping is shared */
3797                 if (shared && (prot & PROT_WRITE))
3798                         av |= FILE__WRITE;
3799
3800                 if (prot & PROT_EXEC)
3801                         av |= FILE__EXECUTE;
3802
3803                 return file_has_perm(cred, file, av);
3804         }
3805
3806 error:
3807         return rc;
3808 }
3809
3810 static int selinux_mmap_addr(unsigned long addr)
3811 {
3812         int rc = 0;
3813
3814         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3815                 u32 sid = current_sid();
3816                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3817                                   MEMPROTECT__MMAP_ZERO, NULL);
3818         }
3819
3820         return rc;
3821 }
3822
3823 static int selinux_mmap_file(struct file *file,
3824                              unsigned long reqprot __always_unused,
3825                              unsigned long prot, unsigned long flags)
3826 {
3827         struct common_audit_data ad;
3828         int rc;
3829
3830         if (file) {
3831                 ad.type = LSM_AUDIT_DATA_FILE;
3832                 ad.u.file = file;
3833                 rc = inode_has_perm(current_cred(), file_inode(file),
3834                                     FILE__MAP, &ad);
3835                 if (rc)
3836                         return rc;
3837         }
3838
3839         return file_map_prot_check(file, prot,
3840                                    (flags & MAP_TYPE) == MAP_SHARED);
3841 }
3842
3843 static int selinux_file_mprotect(struct vm_area_struct *vma,
3844                                  unsigned long reqprot __always_unused,
3845                                  unsigned long prot)
3846 {
3847         const struct cred *cred = current_cred();
3848         u32 sid = cred_sid(cred);
3849
3850         if (default_noexec &&
3851             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3852                 int rc = 0;
3853                 if (vma_is_initial_heap(vma)) {
3854                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3855                                           PROCESS__EXECHEAP, NULL);
3856                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3857                             vma_is_stack_for_current(vma))) {
3858                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3859                                           PROCESS__EXECSTACK, NULL);
3860                 } else if (vma->vm_file && vma->anon_vma) {
3861                         /*
3862                          * We are making executable a file mapping that has
3863                          * had some COW done. Since pages might have been
3864                          * written, check ability to execute the possibly
3865                          * modified content.  This typically should only
3866                          * occur for text relocations.
3867                          */
3868                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3869                 }
3870                 if (rc)
3871                         return rc;
3872         }
3873
3874         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3875 }
3876
3877 static int selinux_file_lock(struct file *file, unsigned int cmd)
3878 {
3879         const struct cred *cred = current_cred();
3880
3881         return file_has_perm(cred, file, FILE__LOCK);
3882 }
3883
3884 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3885                               unsigned long arg)
3886 {
3887         const struct cred *cred = current_cred();
3888         int err = 0;
3889
3890         switch (cmd) {
3891         case F_SETFL:
3892                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3893                         err = file_has_perm(cred, file, FILE__WRITE);
3894                         break;
3895                 }
3896                 fallthrough;
3897         case F_SETOWN:
3898         case F_SETSIG:
3899         case F_GETFL:
3900         case F_GETOWN:
3901         case F_GETSIG:
3902         case F_GETOWNER_UIDS:
3903                 /* Just check FD__USE permission */
3904                 err = file_has_perm(cred, file, 0);
3905                 break;
3906         case F_GETLK:
3907         case F_SETLK:
3908         case F_SETLKW:
3909         case F_OFD_GETLK:
3910         case F_OFD_SETLK:
3911         case F_OFD_SETLKW:
3912 #if BITS_PER_LONG == 32
3913         case F_GETLK64:
3914         case F_SETLK64:
3915         case F_SETLKW64:
3916 #endif
3917                 err = file_has_perm(cred, file, FILE__LOCK);
3918                 break;
3919         }
3920
3921         return err;
3922 }
3923
3924 static void selinux_file_set_fowner(struct file *file)
3925 {
3926         struct file_security_struct *fsec;
3927
3928         fsec = selinux_file(file);
3929         fsec->fown_sid = current_sid();
3930 }
3931
3932 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3933                                        struct fown_struct *fown, int signum)
3934 {
3935         struct file *file;
3936         u32 sid = task_sid_obj(tsk);
3937         u32 perm;
3938         struct file_security_struct *fsec;
3939
3940         /* struct fown_struct is never outside the context of a struct file */
3941         file = container_of(fown, struct file, f_owner);
3942
3943         fsec = selinux_file(file);
3944
3945         if (!signum)
3946                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3947         else
3948                 perm = signal_to_av(signum);
3949
3950         return avc_has_perm(fsec->fown_sid, sid,
3951                             SECCLASS_PROCESS, perm, NULL);
3952 }
3953
3954 static int selinux_file_receive(struct file *file)
3955 {
3956         const struct cred *cred = current_cred();
3957
3958         return file_has_perm(cred, file, file_to_av(file));
3959 }
3960
3961 static int selinux_file_open(struct file *file)
3962 {
3963         struct file_security_struct *fsec;
3964         struct inode_security_struct *isec;
3965
3966         fsec = selinux_file(file);
3967         isec = inode_security(file_inode(file));
3968         /*
3969          * Save inode label and policy sequence number
3970          * at open-time so that selinux_file_permission
3971          * can determine whether revalidation is necessary.
3972          * Task label is already saved in the file security
3973          * struct as its SID.
3974          */
3975         fsec->isid = isec->sid;
3976         fsec->pseqno = avc_policy_seqno();
3977         /*
3978          * Since the inode label or policy seqno may have changed
3979          * between the selinux_inode_permission check and the saving
3980          * of state above, recheck that access is still permitted.
3981          * Otherwise, access might never be revalidated against the
3982          * new inode label or new policy.
3983          * This check is not redundant - do not remove.
3984          */
3985         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3986 }
3987
3988 /* task security operations */
3989
3990 static int selinux_task_alloc(struct task_struct *task,
3991                               unsigned long clone_flags)
3992 {
3993         u32 sid = current_sid();
3994
3995         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3996 }
3997
3998 /*
3999  * prepare a new set of credentials for modification
4000  */
4001 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4002                                 gfp_t gfp)
4003 {
4004         const struct task_security_struct *old_tsec = selinux_cred(old);
4005         struct task_security_struct *tsec = selinux_cred(new);
4006
4007         *tsec = *old_tsec;
4008         return 0;
4009 }
4010
4011 /*
4012  * transfer the SELinux data to a blank set of creds
4013  */
4014 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4015 {
4016         const struct task_security_struct *old_tsec = selinux_cred(old);
4017         struct task_security_struct *tsec = selinux_cred(new);
4018
4019         *tsec = *old_tsec;
4020 }
4021
4022 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4023 {
4024         *secid = cred_sid(c);
4025 }
4026
4027 /*
4028  * set the security data for a kernel service
4029  * - all the creation contexts are set to unlabelled
4030  */
4031 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4032 {
4033         struct task_security_struct *tsec = selinux_cred(new);
4034         u32 sid = current_sid();
4035         int ret;
4036
4037         ret = avc_has_perm(sid, secid,
4038                            SECCLASS_KERNEL_SERVICE,
4039                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4040                            NULL);
4041         if (ret == 0) {
4042                 tsec->sid = secid;
4043                 tsec->create_sid = 0;
4044                 tsec->keycreate_sid = 0;
4045                 tsec->sockcreate_sid = 0;
4046         }
4047         return ret;
4048 }
4049
4050 /*
4051  * set the file creation context in a security record to the same as the
4052  * objective context of the specified inode
4053  */
4054 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4055 {
4056         struct inode_security_struct *isec = inode_security(inode);
4057         struct task_security_struct *tsec = selinux_cred(new);
4058         u32 sid = current_sid();
4059         int ret;
4060
4061         ret = avc_has_perm(sid, isec->sid,
4062                            SECCLASS_KERNEL_SERVICE,
4063                            KERNEL_SERVICE__CREATE_FILES_AS,
4064                            NULL);
4065
4066         if (ret == 0)
4067                 tsec->create_sid = isec->sid;
4068         return ret;
4069 }
4070
4071 static int selinux_kernel_module_request(char *kmod_name)
4072 {
4073         struct common_audit_data ad;
4074
4075         ad.type = LSM_AUDIT_DATA_KMOD;
4076         ad.u.kmod_name = kmod_name;
4077
4078         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4079                             SYSTEM__MODULE_REQUEST, &ad);
4080 }
4081
4082 static int selinux_kernel_module_from_file(struct file *file)
4083 {
4084         struct common_audit_data ad;
4085         struct inode_security_struct *isec;
4086         struct file_security_struct *fsec;
4087         u32 sid = current_sid();
4088         int rc;
4089
4090         /* init_module */
4091         if (file == NULL)
4092                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4093                                         SYSTEM__MODULE_LOAD, NULL);
4094
4095         /* finit_module */
4096
4097         ad.type = LSM_AUDIT_DATA_FILE;
4098         ad.u.file = file;
4099
4100         fsec = selinux_file(file);
4101         if (sid != fsec->sid) {
4102                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4103                 if (rc)
4104                         return rc;
4105         }
4106
4107         isec = inode_security(file_inode(file));
4108         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4109                                 SYSTEM__MODULE_LOAD, &ad);
4110 }
4111
4112 static int selinux_kernel_read_file(struct file *file,
4113                                     enum kernel_read_file_id id,
4114                                     bool contents)
4115 {
4116         int rc = 0;
4117
4118         switch (id) {
4119         case READING_MODULE:
4120                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4121                 break;
4122         default:
4123                 break;
4124         }
4125
4126         return rc;
4127 }
4128
4129 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4130 {
4131         int rc = 0;
4132
4133         switch (id) {
4134         case LOADING_MODULE:
4135                 rc = selinux_kernel_module_from_file(NULL);
4136                 break;
4137         default:
4138                 break;
4139         }
4140
4141         return rc;
4142 }
4143
4144 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4145 {
4146         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4147                             PROCESS__SETPGID, NULL);
4148 }
4149
4150 static int selinux_task_getpgid(struct task_struct *p)
4151 {
4152         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4153                             PROCESS__GETPGID, NULL);
4154 }
4155
4156 static int selinux_task_getsid(struct task_struct *p)
4157 {
4158         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4159                             PROCESS__GETSESSION, NULL);
4160 }
4161
4162 static void selinux_current_getsecid_subj(u32 *secid)
4163 {
4164         *secid = current_sid();
4165 }
4166
4167 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4168 {
4169         *secid = task_sid_obj(p);
4170 }
4171
4172 static int selinux_task_setnice(struct task_struct *p, int nice)
4173 {
4174         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4175                             PROCESS__SETSCHED, NULL);
4176 }
4177
4178 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4179 {
4180         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4181                             PROCESS__SETSCHED, NULL);
4182 }
4183
4184 static int selinux_task_getioprio(struct task_struct *p)
4185 {
4186         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4187                             PROCESS__GETSCHED, NULL);
4188 }
4189
4190 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4191                                 unsigned int flags)
4192 {
4193         u32 av = 0;
4194
4195         if (!flags)
4196                 return 0;
4197         if (flags & LSM_PRLIMIT_WRITE)
4198                 av |= PROCESS__SETRLIMIT;
4199         if (flags & LSM_PRLIMIT_READ)
4200                 av |= PROCESS__GETRLIMIT;
4201         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4202                             SECCLASS_PROCESS, av, NULL);
4203 }
4204
4205 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4206                 struct rlimit *new_rlim)
4207 {
4208         struct rlimit *old_rlim = p->signal->rlim + resource;
4209
4210         /* Control the ability to change the hard limit (whether
4211            lowering or raising it), so that the hard limit can
4212            later be used as a safe reset point for the soft limit
4213            upon context transitions.  See selinux_bprm_committing_creds. */
4214         if (old_rlim->rlim_max != new_rlim->rlim_max)
4215                 return avc_has_perm(current_sid(), task_sid_obj(p),
4216                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4217
4218         return 0;
4219 }
4220
4221 static int selinux_task_setscheduler(struct task_struct *p)
4222 {
4223         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4224                             PROCESS__SETSCHED, NULL);
4225 }
4226
4227 static int selinux_task_getscheduler(struct task_struct *p)
4228 {
4229         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4230                             PROCESS__GETSCHED, NULL);
4231 }
4232
4233 static int selinux_task_movememory(struct task_struct *p)
4234 {
4235         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4236                             PROCESS__SETSCHED, NULL);
4237 }
4238
4239 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4240                                 int sig, const struct cred *cred)
4241 {
4242         u32 secid;
4243         u32 perm;
4244
4245         if (!sig)
4246                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4247         else
4248                 perm = signal_to_av(sig);
4249         if (!cred)
4250                 secid = current_sid();
4251         else
4252                 secid = cred_sid(cred);
4253         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4254 }
4255
4256 static void selinux_task_to_inode(struct task_struct *p,
4257                                   struct inode *inode)
4258 {
4259         struct inode_security_struct *isec = selinux_inode(inode);
4260         u32 sid = task_sid_obj(p);
4261
4262         spin_lock(&isec->lock);
4263         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4264         isec->sid = sid;
4265         isec->initialized = LABEL_INITIALIZED;
4266         spin_unlock(&isec->lock);
4267 }
4268
4269 static int selinux_userns_create(const struct cred *cred)
4270 {
4271         u32 sid = current_sid();
4272
4273         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4274                         USER_NAMESPACE__CREATE, NULL);
4275 }
4276
4277 /* Returns error only if unable to parse addresses */
4278 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4279                         struct common_audit_data *ad, u8 *proto)
4280 {
4281         int offset, ihlen, ret = -EINVAL;
4282         struct iphdr _iph, *ih;
4283
4284         offset = skb_network_offset(skb);
4285         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4286         if (ih == NULL)
4287                 goto out;
4288
4289         ihlen = ih->ihl * 4;
4290         if (ihlen < sizeof(_iph))
4291                 goto out;
4292
4293         ad->u.net->v4info.saddr = ih->saddr;
4294         ad->u.net->v4info.daddr = ih->daddr;
4295         ret = 0;
4296
4297         if (proto)
4298                 *proto = ih->protocol;
4299
4300         switch (ih->protocol) {
4301         case IPPROTO_TCP: {
4302                 struct tcphdr _tcph, *th;
4303
4304                 if (ntohs(ih->frag_off) & IP_OFFSET)
4305                         break;
4306
4307                 offset += ihlen;
4308                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4309                 if (th == NULL)
4310                         break;
4311
4312                 ad->u.net->sport = th->source;
4313                 ad->u.net->dport = th->dest;
4314                 break;
4315         }
4316
4317         case IPPROTO_UDP: {
4318                 struct udphdr _udph, *uh;
4319
4320                 if (ntohs(ih->frag_off) & IP_OFFSET)
4321                         break;
4322
4323                 offset += ihlen;
4324                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4325                 if (uh == NULL)
4326                         break;
4327
4328                 ad->u.net->sport = uh->source;
4329                 ad->u.net->dport = uh->dest;
4330                 break;
4331         }
4332
4333         case IPPROTO_DCCP: {
4334                 struct dccp_hdr _dccph, *dh;
4335
4336                 if (ntohs(ih->frag_off) & IP_OFFSET)
4337                         break;
4338
4339                 offset += ihlen;
4340                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4341                 if (dh == NULL)
4342                         break;
4343
4344                 ad->u.net->sport = dh->dccph_sport;
4345                 ad->u.net->dport = dh->dccph_dport;
4346                 break;
4347         }
4348
4349 #if IS_ENABLED(CONFIG_IP_SCTP)
4350         case IPPROTO_SCTP: {
4351                 struct sctphdr _sctph, *sh;
4352
4353                 if (ntohs(ih->frag_off) & IP_OFFSET)
4354                         break;
4355
4356                 offset += ihlen;
4357                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4358                 if (sh == NULL)
4359                         break;
4360
4361                 ad->u.net->sport = sh->source;
4362                 ad->u.net->dport = sh->dest;
4363                 break;
4364         }
4365 #endif
4366         default:
4367                 break;
4368         }
4369 out:
4370         return ret;
4371 }
4372
4373 #if IS_ENABLED(CONFIG_IPV6)
4374
4375 /* Returns error only if unable to parse addresses */
4376 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4377                         struct common_audit_data *ad, u8 *proto)
4378 {
4379         u8 nexthdr;
4380         int ret = -EINVAL, offset;
4381         struct ipv6hdr _ipv6h, *ip6;
4382         __be16 frag_off;
4383
4384         offset = skb_network_offset(skb);
4385         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4386         if (ip6 == NULL)
4387                 goto out;
4388
4389         ad->u.net->v6info.saddr = ip6->saddr;
4390         ad->u.net->v6info.daddr = ip6->daddr;
4391         ret = 0;
4392
4393         nexthdr = ip6->nexthdr;
4394         offset += sizeof(_ipv6h);
4395         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4396         if (offset < 0)
4397                 goto out;
4398
4399         if (proto)
4400                 *proto = nexthdr;
4401
4402         switch (nexthdr) {
4403         case IPPROTO_TCP: {
4404                 struct tcphdr _tcph, *th;
4405
4406                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4407                 if (th == NULL)
4408                         break;
4409
4410                 ad->u.net->sport = th->source;
4411                 ad->u.net->dport = th->dest;
4412                 break;
4413         }
4414
4415         case IPPROTO_UDP: {
4416                 struct udphdr _udph, *uh;
4417
4418                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4419                 if (uh == NULL)
4420                         break;
4421
4422                 ad->u.net->sport = uh->source;
4423                 ad->u.net->dport = uh->dest;
4424                 break;
4425         }
4426
4427         case IPPROTO_DCCP: {
4428                 struct dccp_hdr _dccph, *dh;
4429
4430                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4431                 if (dh == NULL)
4432                         break;
4433
4434                 ad->u.net->sport = dh->dccph_sport;
4435                 ad->u.net->dport = dh->dccph_dport;
4436                 break;
4437         }
4438
4439 #if IS_ENABLED(CONFIG_IP_SCTP)
4440         case IPPROTO_SCTP: {
4441                 struct sctphdr _sctph, *sh;
4442
4443                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4444                 if (sh == NULL)
4445                         break;
4446
4447                 ad->u.net->sport = sh->source;
4448                 ad->u.net->dport = sh->dest;
4449                 break;
4450         }
4451 #endif
4452         /* includes fragments */
4453         default:
4454                 break;
4455         }
4456 out:
4457         return ret;
4458 }
4459
4460 #endif /* IPV6 */
4461
4462 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4463                              char **_addrp, int src, u8 *proto)
4464 {
4465         char *addrp;
4466         int ret;
4467
4468         switch (ad->u.net->family) {
4469         case PF_INET:
4470                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4471                 if (ret)
4472                         goto parse_error;
4473                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4474                                        &ad->u.net->v4info.daddr);
4475                 goto okay;
4476
4477 #if IS_ENABLED(CONFIG_IPV6)
4478         case PF_INET6:
4479                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4480                 if (ret)
4481                         goto parse_error;
4482                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4483                                        &ad->u.net->v6info.daddr);
4484                 goto okay;
4485 #endif  /* IPV6 */
4486         default:
4487                 addrp = NULL;
4488                 goto okay;
4489         }
4490
4491 parse_error:
4492         pr_warn(
4493                "SELinux: failure in selinux_parse_skb(),"
4494                " unable to parse packet\n");
4495         return ret;
4496
4497 okay:
4498         if (_addrp)
4499                 *_addrp = addrp;
4500         return 0;
4501 }
4502
4503 /**
4504  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4505  * @skb: the packet
4506  * @family: protocol family
4507  * @sid: the packet's peer label SID
4508  *
4509  * Description:
4510  * Check the various different forms of network peer labeling and determine
4511  * the peer label/SID for the packet; most of the magic actually occurs in
4512  * the security server function security_net_peersid_cmp().  The function
4513  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4514  * or -EACCES if @sid is invalid due to inconsistencies with the different
4515  * peer labels.
4516  *
4517  */
4518 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4519 {
4520         int err;
4521         u32 xfrm_sid;
4522         u32 nlbl_sid;
4523         u32 nlbl_type;
4524
4525         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4526         if (unlikely(err))
4527                 return -EACCES;
4528         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4529         if (unlikely(err))
4530                 return -EACCES;
4531
4532         err = security_net_peersid_resolve(nlbl_sid,
4533                                            nlbl_type, xfrm_sid, sid);
4534         if (unlikely(err)) {
4535                 pr_warn(
4536                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4537                        " unable to determine packet's peer label\n");
4538                 return -EACCES;
4539         }
4540
4541         return 0;
4542 }
4543
4544 /**
4545  * selinux_conn_sid - Determine the child socket label for a connection
4546  * @sk_sid: the parent socket's SID
4547  * @skb_sid: the packet's SID
4548  * @conn_sid: the resulting connection SID
4549  *
4550  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4551  * combined with the MLS information from @skb_sid in order to create
4552  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4553  * of @sk_sid.  Returns zero on success, negative values on failure.
4554  *
4555  */
4556 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4557 {
4558         int err = 0;
4559
4560         if (skb_sid != SECSID_NULL)
4561                 err = security_sid_mls_copy(sk_sid, skb_sid,
4562                                             conn_sid);
4563         else
4564                 *conn_sid = sk_sid;
4565
4566         return err;
4567 }
4568
4569 /* socket security operations */
4570
4571 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4572                                  u16 secclass, u32 *socksid)
4573 {
4574         if (tsec->sockcreate_sid > SECSID_NULL) {
4575                 *socksid = tsec->sockcreate_sid;
4576                 return 0;
4577         }
4578
4579         return security_transition_sid(tsec->sid, tsec->sid,
4580                                        secclass, NULL, socksid);
4581 }
4582
4583 static int sock_has_perm(struct sock *sk, u32 perms)
4584 {
4585         struct sk_security_struct *sksec = sk->sk_security;
4586         struct common_audit_data ad;
4587         struct lsm_network_audit net;
4588
4589         if (sksec->sid == SECINITSID_KERNEL)
4590                 return 0;
4591
4592         /*
4593          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4594          * inherited the kernel context from early boot used to be skipped
4595          * here, so preserve that behavior unless the capability is set.
4596          *
4597          * By setting the capability the policy signals that it is ready
4598          * for this quirk to be fixed. Note that sockets created by a kernel
4599          * thread or a usermode helper executed without a transition will
4600          * still be skipped in this check regardless of the policycap
4601          * setting.
4602          */
4603         if (!selinux_policycap_userspace_initial_context() &&
4604             sksec->sid == SECINITSID_INIT)
4605                 return 0;
4606
4607         ad_net_init_from_sk(&ad, &net, sk);
4608
4609         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4610                             &ad);
4611 }
4612
4613 static int selinux_socket_create(int family, int type,
4614                                  int protocol, int kern)
4615 {
4616         const struct task_security_struct *tsec = selinux_cred(current_cred());
4617         u32 newsid;
4618         u16 secclass;
4619         int rc;
4620
4621         if (kern)
4622                 return 0;
4623
4624         secclass = socket_type_to_security_class(family, type, protocol);
4625         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4626         if (rc)
4627                 return rc;
4628
4629         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4630 }
4631
4632 static int selinux_socket_post_create(struct socket *sock, int family,
4633                                       int type, int protocol, int kern)
4634 {
4635         const struct task_security_struct *tsec = selinux_cred(current_cred());
4636         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4637         struct sk_security_struct *sksec;
4638         u16 sclass = socket_type_to_security_class(family, type, protocol);
4639         u32 sid = SECINITSID_KERNEL;
4640         int err = 0;
4641
4642         if (!kern) {
4643                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4644                 if (err)
4645                         return err;
4646         }
4647
4648         isec->sclass = sclass;
4649         isec->sid = sid;
4650         isec->initialized = LABEL_INITIALIZED;
4651
4652         if (sock->sk) {
4653                 sksec = sock->sk->sk_security;
4654                 sksec->sclass = sclass;
4655                 sksec->sid = sid;
4656                 /* Allows detection of the first association on this socket */
4657                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4658                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4659
4660                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4661         }
4662
4663         return err;
4664 }
4665
4666 static int selinux_socket_socketpair(struct socket *socka,
4667                                      struct socket *sockb)
4668 {
4669         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4670         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4671
4672         sksec_a->peer_sid = sksec_b->sid;
4673         sksec_b->peer_sid = sksec_a->sid;
4674
4675         return 0;
4676 }
4677
4678 /* Range of port numbers used to automatically bind.
4679    Need to determine whether we should perform a name_bind
4680    permission check between the socket and the port number. */
4681
4682 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4683 {
4684         struct sock *sk = sock->sk;
4685         struct sk_security_struct *sksec = sk->sk_security;
4686         u16 family;
4687         int err;
4688
4689         err = sock_has_perm(sk, SOCKET__BIND);
4690         if (err)
4691                 goto out;
4692
4693         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4694         family = sk->sk_family;
4695         if (family == PF_INET || family == PF_INET6) {
4696                 char *addrp;
4697                 struct common_audit_data ad;
4698                 struct lsm_network_audit net = {0,};
4699                 struct sockaddr_in *addr4 = NULL;
4700                 struct sockaddr_in6 *addr6 = NULL;
4701                 u16 family_sa;
4702                 unsigned short snum;
4703                 u32 sid, node_perm;
4704
4705                 /*
4706                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4707                  * that validates multiple binding addresses. Because of this
4708                  * need to check address->sa_family as it is possible to have
4709                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4710                  */
4711                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4712                         return -EINVAL;
4713                 family_sa = address->sa_family;
4714                 switch (family_sa) {
4715                 case AF_UNSPEC:
4716                 case AF_INET:
4717                         if (addrlen < sizeof(struct sockaddr_in))
4718                                 return -EINVAL;
4719                         addr4 = (struct sockaddr_in *)address;
4720                         if (family_sa == AF_UNSPEC) {
4721                                 if (family == PF_INET6) {
4722                                         /* Length check from inet6_bind_sk() */
4723                                         if (addrlen < SIN6_LEN_RFC2133)
4724                                                 return -EINVAL;
4725                                         /* Family check from __inet6_bind() */
4726                                         goto err_af;
4727                                 }
4728                                 /* see __inet_bind(), we only want to allow
4729                                  * AF_UNSPEC if the address is INADDR_ANY
4730                                  */
4731                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4732                                         goto err_af;
4733                                 family_sa = AF_INET;
4734                         }
4735                         snum = ntohs(addr4->sin_port);
4736                         addrp = (char *)&addr4->sin_addr.s_addr;
4737                         break;
4738                 case AF_INET6:
4739                         if (addrlen < SIN6_LEN_RFC2133)
4740                                 return -EINVAL;
4741                         addr6 = (struct sockaddr_in6 *)address;
4742                         snum = ntohs(addr6->sin6_port);
4743                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4744                         break;
4745                 default:
4746                         goto err_af;
4747                 }
4748
4749                 ad.type = LSM_AUDIT_DATA_NET;
4750                 ad.u.net = &net;
4751                 ad.u.net->sport = htons(snum);
4752                 ad.u.net->family = family_sa;
4753
4754                 if (snum) {
4755                         int low, high;
4756
4757                         inet_get_local_port_range(sock_net(sk), &low, &high);
4758
4759                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4760                             snum < low || snum > high) {
4761                                 err = sel_netport_sid(sk->sk_protocol,
4762                                                       snum, &sid);
4763                                 if (err)
4764                                         goto out;
4765                                 err = avc_has_perm(sksec->sid, sid,
4766                                                    sksec->sclass,
4767                                                    SOCKET__NAME_BIND, &ad);
4768                                 if (err)
4769                                         goto out;
4770                         }
4771                 }
4772
4773                 switch (sksec->sclass) {
4774                 case SECCLASS_TCP_SOCKET:
4775                         node_perm = TCP_SOCKET__NODE_BIND;
4776                         break;
4777
4778                 case SECCLASS_UDP_SOCKET:
4779                         node_perm = UDP_SOCKET__NODE_BIND;
4780                         break;
4781
4782                 case SECCLASS_DCCP_SOCKET:
4783                         node_perm = DCCP_SOCKET__NODE_BIND;
4784                         break;
4785
4786                 case SECCLASS_SCTP_SOCKET:
4787                         node_perm = SCTP_SOCKET__NODE_BIND;
4788                         break;
4789
4790                 default:
4791                         node_perm = RAWIP_SOCKET__NODE_BIND;
4792                         break;
4793                 }
4794
4795                 err = sel_netnode_sid(addrp, family_sa, &sid);
4796                 if (err)
4797                         goto out;
4798
4799                 if (family_sa == AF_INET)
4800                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4801                 else
4802                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4803
4804                 err = avc_has_perm(sksec->sid, sid,
4805                                    sksec->sclass, node_perm, &ad);
4806                 if (err)
4807                         goto out;
4808         }
4809 out:
4810         return err;
4811 err_af:
4812         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4813         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4814                 return -EINVAL;
4815         return -EAFNOSUPPORT;
4816 }
4817
4818 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4819  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4820  */
4821 static int selinux_socket_connect_helper(struct socket *sock,
4822                                          struct sockaddr *address, int addrlen)
4823 {
4824         struct sock *sk = sock->sk;
4825         struct sk_security_struct *sksec = sk->sk_security;
4826         int err;
4827
4828         err = sock_has_perm(sk, SOCKET__CONNECT);
4829         if (err)
4830                 return err;
4831         if (addrlen < offsetofend(struct sockaddr, sa_family))
4832                 return -EINVAL;
4833
4834         /* connect(AF_UNSPEC) has special handling, as it is a documented
4835          * way to disconnect the socket
4836          */
4837         if (address->sa_family == AF_UNSPEC)
4838                 return 0;
4839
4840         /*
4841          * If a TCP, DCCP or SCTP socket, check name_connect permission
4842          * for the port.
4843          */
4844         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4845             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4846             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4847                 struct common_audit_data ad;
4848                 struct lsm_network_audit net = {0,};
4849                 struct sockaddr_in *addr4 = NULL;
4850                 struct sockaddr_in6 *addr6 = NULL;
4851                 unsigned short snum;
4852                 u32 sid, perm;
4853
4854                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4855                  * that validates multiple connect addresses. Because of this
4856                  * need to check address->sa_family as it is possible to have
4857                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4858                  */
4859                 switch (address->sa_family) {
4860                 case AF_INET:
4861                         addr4 = (struct sockaddr_in *)address;
4862                         if (addrlen < sizeof(struct sockaddr_in))
4863                                 return -EINVAL;
4864                         snum = ntohs(addr4->sin_port);
4865                         break;
4866                 case AF_INET6:
4867                         addr6 = (struct sockaddr_in6 *)address;
4868                         if (addrlen < SIN6_LEN_RFC2133)
4869                                 return -EINVAL;
4870                         snum = ntohs(addr6->sin6_port);
4871                         break;
4872                 default:
4873                         /* Note that SCTP services expect -EINVAL, whereas
4874                          * others expect -EAFNOSUPPORT.
4875                          */
4876                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4877                                 return -EINVAL;
4878                         else
4879                                 return -EAFNOSUPPORT;
4880                 }
4881
4882                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4883                 if (err)
4884                         return err;
4885
4886                 switch (sksec->sclass) {
4887                 case SECCLASS_TCP_SOCKET:
4888                         perm = TCP_SOCKET__NAME_CONNECT;
4889                         break;
4890                 case SECCLASS_DCCP_SOCKET:
4891                         perm = DCCP_SOCKET__NAME_CONNECT;
4892                         break;
4893                 case SECCLASS_SCTP_SOCKET:
4894                         perm = SCTP_SOCKET__NAME_CONNECT;
4895                         break;
4896                 }
4897
4898                 ad.type = LSM_AUDIT_DATA_NET;
4899                 ad.u.net = &net;
4900                 ad.u.net->dport = htons(snum);
4901                 ad.u.net->family = address->sa_family;
4902                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4903                 if (err)
4904                         return err;
4905         }
4906
4907         return 0;
4908 }
4909
4910 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4911 static int selinux_socket_connect(struct socket *sock,
4912                                   struct sockaddr *address, int addrlen)
4913 {
4914         int err;
4915         struct sock *sk = sock->sk;
4916
4917         err = selinux_socket_connect_helper(sock, address, addrlen);
4918         if (err)
4919                 return err;
4920
4921         return selinux_netlbl_socket_connect(sk, address);
4922 }
4923
4924 static int selinux_socket_listen(struct socket *sock, int backlog)
4925 {
4926         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4927 }
4928
4929 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4930 {
4931         int err;
4932         struct inode_security_struct *isec;
4933         struct inode_security_struct *newisec;
4934         u16 sclass;
4935         u32 sid;
4936
4937         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4938         if (err)
4939                 return err;
4940
4941         isec = inode_security_novalidate(SOCK_INODE(sock));
4942         spin_lock(&isec->lock);
4943         sclass = isec->sclass;
4944         sid = isec->sid;
4945         spin_unlock(&isec->lock);
4946
4947         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4948         newisec->sclass = sclass;
4949         newisec->sid = sid;
4950         newisec->initialized = LABEL_INITIALIZED;
4951
4952         return 0;
4953 }
4954
4955 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4956                                   int size)
4957 {
4958         return sock_has_perm(sock->sk, SOCKET__WRITE);
4959 }
4960
4961 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4962                                   int size, int flags)
4963 {
4964         return sock_has_perm(sock->sk, SOCKET__READ);
4965 }
4966
4967 static int selinux_socket_getsockname(struct socket *sock)
4968 {
4969         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4970 }
4971
4972 static int selinux_socket_getpeername(struct socket *sock)
4973 {
4974         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4975 }
4976
4977 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4978 {
4979         int err;
4980
4981         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4982         if (err)
4983                 return err;
4984
4985         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4986 }
4987
4988 static int selinux_socket_getsockopt(struct socket *sock, int level,
4989                                      int optname)
4990 {
4991         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4992 }
4993
4994 static int selinux_socket_shutdown(struct socket *sock, int how)
4995 {
4996         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4997 }
4998
4999 static int selinux_socket_unix_stream_connect(struct sock *sock,
5000                                               struct sock *other,
5001                                               struct sock *newsk)
5002 {
5003         struct sk_security_struct *sksec_sock = sock->sk_security;
5004         struct sk_security_struct *sksec_other = other->sk_security;
5005         struct sk_security_struct *sksec_new = newsk->sk_security;
5006         struct common_audit_data ad;
5007         struct lsm_network_audit net;
5008         int err;
5009
5010         ad_net_init_from_sk(&ad, &net, other);
5011
5012         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5013                            sksec_other->sclass,
5014                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5015         if (err)
5016                 return err;
5017
5018         /* server child socket */
5019         sksec_new->peer_sid = sksec_sock->sid;
5020         err = security_sid_mls_copy(sksec_other->sid,
5021                                     sksec_sock->sid, &sksec_new->sid);
5022         if (err)
5023                 return err;
5024
5025         /* connecting socket */
5026         sksec_sock->peer_sid = sksec_new->sid;
5027
5028         return 0;
5029 }
5030
5031 static int selinux_socket_unix_may_send(struct socket *sock,
5032                                         struct socket *other)
5033 {
5034         struct sk_security_struct *ssec = sock->sk->sk_security;
5035         struct sk_security_struct *osec = other->sk->sk_security;
5036         struct common_audit_data ad;
5037         struct lsm_network_audit net;
5038
5039         ad_net_init_from_sk(&ad, &net, other->sk);
5040
5041         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5042                             &ad);
5043 }
5044
5045 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5046                                     char *addrp, u16 family, u32 peer_sid,
5047                                     struct common_audit_data *ad)
5048 {
5049         int err;
5050         u32 if_sid;
5051         u32 node_sid;
5052
5053         err = sel_netif_sid(ns, ifindex, &if_sid);
5054         if (err)
5055                 return err;
5056         err = avc_has_perm(peer_sid, if_sid,
5057                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5058         if (err)
5059                 return err;
5060
5061         err = sel_netnode_sid(addrp, family, &node_sid);
5062         if (err)
5063                 return err;
5064         return avc_has_perm(peer_sid, node_sid,
5065                             SECCLASS_NODE, NODE__RECVFROM, ad);
5066 }
5067
5068 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5069                                        u16 family)
5070 {
5071         int err = 0;
5072         struct sk_security_struct *sksec = sk->sk_security;
5073         u32 sk_sid = sksec->sid;
5074         struct common_audit_data ad;
5075         struct lsm_network_audit net;
5076         char *addrp;
5077
5078         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5079         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5080         if (err)
5081                 return err;
5082
5083         if (selinux_secmark_enabled()) {
5084                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5085                                    PACKET__RECV, &ad);
5086                 if (err)
5087                         return err;
5088         }
5089
5090         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5091         if (err)
5092                 return err;
5093         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5094
5095         return err;
5096 }
5097
5098 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5099 {
5100         int err, peerlbl_active, secmark_active;
5101         struct sk_security_struct *sksec = sk->sk_security;
5102         u16 family = sk->sk_family;
5103         u32 sk_sid = sksec->sid;
5104         struct common_audit_data ad;
5105         struct lsm_network_audit net;
5106         char *addrp;
5107
5108         if (family != PF_INET && family != PF_INET6)
5109                 return 0;
5110
5111         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5112         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5113                 family = PF_INET;
5114
5115         /* If any sort of compatibility mode is enabled then handoff processing
5116          * to the selinux_sock_rcv_skb_compat() function to deal with the
5117          * special handling.  We do this in an attempt to keep this function
5118          * as fast and as clean as possible. */
5119         if (!selinux_policycap_netpeer())
5120                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5121
5122         secmark_active = selinux_secmark_enabled();
5123         peerlbl_active = selinux_peerlbl_enabled();
5124         if (!secmark_active && !peerlbl_active)
5125                 return 0;
5126
5127         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5128         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5129         if (err)
5130                 return err;
5131
5132         if (peerlbl_active) {
5133                 u32 peer_sid;
5134
5135                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5136                 if (err)
5137                         return err;
5138                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5139                                                addrp, family, peer_sid, &ad);
5140                 if (err) {
5141                         selinux_netlbl_err(skb, family, err, 0);
5142                         return err;
5143                 }
5144                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5145                                    PEER__RECV, &ad);
5146                 if (err) {
5147                         selinux_netlbl_err(skb, family, err, 0);
5148                         return err;
5149                 }
5150         }
5151
5152         if (secmark_active) {
5153                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5154                                    PACKET__RECV, &ad);
5155                 if (err)
5156                         return err;
5157         }
5158
5159         return err;
5160 }
5161
5162 static int selinux_socket_getpeersec_stream(struct socket *sock,
5163                                             sockptr_t optval, sockptr_t optlen,
5164                                             unsigned int len)
5165 {
5166         int err = 0;
5167         char *scontext = NULL;
5168         u32 scontext_len;
5169         struct sk_security_struct *sksec = sock->sk->sk_security;
5170         u32 peer_sid = SECSID_NULL;
5171
5172         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5173             sksec->sclass == SECCLASS_TCP_SOCKET ||
5174             sksec->sclass == SECCLASS_SCTP_SOCKET)
5175                 peer_sid = sksec->peer_sid;
5176         if (peer_sid == SECSID_NULL)
5177                 return -ENOPROTOOPT;
5178
5179         err = security_sid_to_context(peer_sid, &scontext,
5180                                       &scontext_len);
5181         if (err)
5182                 return err;
5183         if (scontext_len > len) {
5184                 err = -ERANGE;
5185                 goto out_len;
5186         }
5187
5188         if (copy_to_sockptr(optval, scontext, scontext_len))
5189                 err = -EFAULT;
5190 out_len:
5191         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5192                 err = -EFAULT;
5193         kfree(scontext);
5194         return err;
5195 }
5196
5197 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5198 {
5199         u32 peer_secid = SECSID_NULL;
5200         u16 family;
5201         struct inode_security_struct *isec;
5202
5203         if (skb && skb->protocol == htons(ETH_P_IP))
5204                 family = PF_INET;
5205         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5206                 family = PF_INET6;
5207         else if (sock)
5208                 family = sock->sk->sk_family;
5209         else
5210                 goto out;
5211
5212         if (sock && family == PF_UNIX) {
5213                 isec = inode_security_novalidate(SOCK_INODE(sock));
5214                 peer_secid = isec->sid;
5215         } else if (skb)
5216                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5217
5218 out:
5219         *secid = peer_secid;
5220         if (peer_secid == SECSID_NULL)
5221                 return -EINVAL;
5222         return 0;
5223 }
5224
5225 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5226 {
5227         struct sk_security_struct *sksec;
5228
5229         sksec = kzalloc(sizeof(*sksec), priority);
5230         if (!sksec)
5231                 return -ENOMEM;
5232
5233         sksec->peer_sid = SECINITSID_UNLABELED;
5234         sksec->sid = SECINITSID_UNLABELED;
5235         sksec->sclass = SECCLASS_SOCKET;
5236         selinux_netlbl_sk_security_reset(sksec);
5237         sk->sk_security = sksec;
5238
5239         return 0;
5240 }
5241
5242 static void selinux_sk_free_security(struct sock *sk)
5243 {
5244         struct sk_security_struct *sksec = sk->sk_security;
5245
5246         sk->sk_security = NULL;
5247         selinux_netlbl_sk_security_free(sksec);
5248         kfree(sksec);
5249 }
5250
5251 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5252 {
5253         struct sk_security_struct *sksec = sk->sk_security;
5254         struct sk_security_struct *newsksec = newsk->sk_security;
5255
5256         newsksec->sid = sksec->sid;
5257         newsksec->peer_sid = sksec->peer_sid;
5258         newsksec->sclass = sksec->sclass;
5259
5260         selinux_netlbl_sk_security_reset(newsksec);
5261 }
5262
5263 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5264 {
5265         if (!sk)
5266                 *secid = SECINITSID_ANY_SOCKET;
5267         else {
5268                 const struct sk_security_struct *sksec = sk->sk_security;
5269
5270                 *secid = sksec->sid;
5271         }
5272 }
5273
5274 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5275 {
5276         struct inode_security_struct *isec =
5277                 inode_security_novalidate(SOCK_INODE(parent));
5278         struct sk_security_struct *sksec = sk->sk_security;
5279
5280         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5281             sk->sk_family == PF_UNIX)
5282                 isec->sid = sksec->sid;
5283         sksec->sclass = isec->sclass;
5284 }
5285
5286 /*
5287  * Determines peer_secid for the asoc and updates socket's peer label
5288  * if it's the first association on the socket.
5289  */
5290 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5291                                           struct sk_buff *skb)
5292 {
5293         struct sock *sk = asoc->base.sk;
5294         u16 family = sk->sk_family;
5295         struct sk_security_struct *sksec = sk->sk_security;
5296         struct common_audit_data ad;
5297         struct lsm_network_audit net;
5298         int err;
5299
5300         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5301         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5302                 family = PF_INET;
5303
5304         if (selinux_peerlbl_enabled()) {
5305                 asoc->peer_secid = SECSID_NULL;
5306
5307                 /* This will return peer_sid = SECSID_NULL if there are
5308                  * no peer labels, see security_net_peersid_resolve().
5309                  */
5310                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5311                 if (err)
5312                         return err;
5313
5314                 if (asoc->peer_secid == SECSID_NULL)
5315                         asoc->peer_secid = SECINITSID_UNLABELED;
5316         } else {
5317                 asoc->peer_secid = SECINITSID_UNLABELED;
5318         }
5319
5320         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5321                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5322
5323                 /* Here as first association on socket. As the peer SID
5324                  * was allowed by peer recv (and the netif/node checks),
5325                  * then it is approved by policy and used as the primary
5326                  * peer SID for getpeercon(3).
5327                  */
5328                 sksec->peer_sid = asoc->peer_secid;
5329         } else if (sksec->peer_sid != asoc->peer_secid) {
5330                 /* Other association peer SIDs are checked to enforce
5331                  * consistency among the peer SIDs.
5332                  */
5333                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5334                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5335                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5336                                    &ad);
5337                 if (err)
5338                         return err;
5339         }
5340         return 0;
5341 }
5342
5343 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5344  * happens on an incoming connect(2), sctp_connectx(3) or
5345  * sctp_sendmsg(3) (with no association already present).
5346  */
5347 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5348                                       struct sk_buff *skb)
5349 {
5350         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5351         u32 conn_sid;
5352         int err;
5353
5354         if (!selinux_policycap_extsockclass())
5355                 return 0;
5356
5357         err = selinux_sctp_process_new_assoc(asoc, skb);
5358         if (err)
5359                 return err;
5360
5361         /* Compute the MLS component for the connection and store
5362          * the information in asoc. This will be used by SCTP TCP type
5363          * sockets and peeled off connections as they cause a new
5364          * socket to be generated. selinux_sctp_sk_clone() will then
5365          * plug this into the new socket.
5366          */
5367         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5368         if (err)
5369                 return err;
5370
5371         asoc->secid = conn_sid;
5372
5373         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5374         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5375 }
5376
5377 /* Called when SCTP receives a COOKIE ACK chunk as the final
5378  * response to an association request (initited by us).
5379  */
5380 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5381                                           struct sk_buff *skb)
5382 {
5383         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5384
5385         if (!selinux_policycap_extsockclass())
5386                 return 0;
5387
5388         /* Inherit secid from the parent socket - this will be picked up
5389          * by selinux_sctp_sk_clone() if the association gets peeled off
5390          * into a new socket.
5391          */
5392         asoc->secid = sksec->sid;
5393
5394         return selinux_sctp_process_new_assoc(asoc, skb);
5395 }
5396
5397 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5398  * based on their @optname.
5399  */
5400 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5401                                      struct sockaddr *address,
5402                                      int addrlen)
5403 {
5404         int len, err = 0, walk_size = 0;
5405         void *addr_buf;
5406         struct sockaddr *addr;
5407         struct socket *sock;
5408
5409         if (!selinux_policycap_extsockclass())
5410                 return 0;
5411
5412         /* Process one or more addresses that may be IPv4 or IPv6 */
5413         sock = sk->sk_socket;
5414         addr_buf = address;
5415
5416         while (walk_size < addrlen) {
5417                 if (walk_size + sizeof(sa_family_t) > addrlen)
5418                         return -EINVAL;
5419
5420                 addr = addr_buf;
5421                 switch (addr->sa_family) {
5422                 case AF_UNSPEC:
5423                 case AF_INET:
5424                         len = sizeof(struct sockaddr_in);
5425                         break;
5426                 case AF_INET6:
5427                         len = sizeof(struct sockaddr_in6);
5428                         break;
5429                 default:
5430                         return -EINVAL;
5431                 }
5432
5433                 if (walk_size + len > addrlen)
5434                         return -EINVAL;
5435
5436                 err = -EINVAL;
5437                 switch (optname) {
5438                 /* Bind checks */
5439                 case SCTP_PRIMARY_ADDR:
5440                 case SCTP_SET_PEER_PRIMARY_ADDR:
5441                 case SCTP_SOCKOPT_BINDX_ADD:
5442                         err = selinux_socket_bind(sock, addr, len);
5443                         break;
5444                 /* Connect checks */
5445                 case SCTP_SOCKOPT_CONNECTX:
5446                 case SCTP_PARAM_SET_PRIMARY:
5447                 case SCTP_PARAM_ADD_IP:
5448                 case SCTP_SENDMSG_CONNECT:
5449                         err = selinux_socket_connect_helper(sock, addr, len);
5450                         if (err)
5451                                 return err;
5452
5453                         /* As selinux_sctp_bind_connect() is called by the
5454                          * SCTP protocol layer, the socket is already locked,
5455                          * therefore selinux_netlbl_socket_connect_locked()
5456                          * is called here. The situations handled are:
5457                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5458                          * whenever a new IP address is added or when a new
5459                          * primary address is selected.
5460                          * Note that an SCTP connect(2) call happens before
5461                          * the SCTP protocol layer and is handled via
5462                          * selinux_socket_connect().
5463                          */
5464                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5465                         break;
5466                 }
5467
5468                 if (err)
5469                         return err;
5470
5471                 addr_buf += len;
5472                 walk_size += len;
5473         }
5474
5475         return 0;
5476 }
5477
5478 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5479 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5480                                   struct sock *newsk)
5481 {
5482         struct sk_security_struct *sksec = sk->sk_security;
5483         struct sk_security_struct *newsksec = newsk->sk_security;
5484
5485         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5486          * the non-sctp clone version.
5487          */
5488         if (!selinux_policycap_extsockclass())
5489                 return selinux_sk_clone_security(sk, newsk);
5490
5491         newsksec->sid = asoc->secid;
5492         newsksec->peer_sid = asoc->peer_secid;
5493         newsksec->sclass = sksec->sclass;
5494         selinux_netlbl_sctp_sk_clone(sk, newsk);
5495 }
5496
5497 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5498 {
5499         struct sk_security_struct *ssksec = ssk->sk_security;
5500         struct sk_security_struct *sksec = sk->sk_security;
5501
5502         ssksec->sclass = sksec->sclass;
5503         ssksec->sid = sksec->sid;
5504
5505         /* replace the existing subflow label deleting the existing one
5506          * and re-recreating a new label using the updated context
5507          */
5508         selinux_netlbl_sk_security_free(ssksec);
5509         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5510 }
5511
5512 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5513                                      struct request_sock *req)
5514 {
5515         struct sk_security_struct *sksec = sk->sk_security;
5516         int err;
5517         u16 family = req->rsk_ops->family;
5518         u32 connsid;
5519         u32 peersid;
5520
5521         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5522         if (err)
5523                 return err;
5524         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5525         if (err)
5526                 return err;
5527         req->secid = connsid;
5528         req->peer_secid = peersid;
5529
5530         return selinux_netlbl_inet_conn_request(req, family);
5531 }
5532
5533 static void selinux_inet_csk_clone(struct sock *newsk,
5534                                    const struct request_sock *req)
5535 {
5536         struct sk_security_struct *newsksec = newsk->sk_security;
5537
5538         newsksec->sid = req->secid;
5539         newsksec->peer_sid = req->peer_secid;
5540         /* NOTE: Ideally, we should also get the isec->sid for the
5541            new socket in sync, but we don't have the isec available yet.
5542            So we will wait until sock_graft to do it, by which
5543            time it will have been created and available. */
5544
5545         /* We don't need to take any sort of lock here as we are the only
5546          * thread with access to newsksec */
5547         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5548 }
5549
5550 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5551 {
5552         u16 family = sk->sk_family;
5553         struct sk_security_struct *sksec = sk->sk_security;
5554
5555         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5556         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5557                 family = PF_INET;
5558
5559         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5560 }
5561
5562 static int selinux_secmark_relabel_packet(u32 sid)
5563 {
5564         const struct task_security_struct *tsec;
5565         u32 tsid;
5566
5567         tsec = selinux_cred(current_cred());
5568         tsid = tsec->sid;
5569
5570         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5571                             NULL);
5572 }
5573
5574 static void selinux_secmark_refcount_inc(void)
5575 {
5576         atomic_inc(&selinux_secmark_refcount);
5577 }
5578
5579 static void selinux_secmark_refcount_dec(void)
5580 {
5581         atomic_dec(&selinux_secmark_refcount);
5582 }
5583
5584 static void selinux_req_classify_flow(const struct request_sock *req,
5585                                       struct flowi_common *flic)
5586 {
5587         flic->flowic_secid = req->secid;
5588 }
5589
5590 static int selinux_tun_dev_alloc_security(void **security)
5591 {
5592         struct tun_security_struct *tunsec;
5593
5594         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5595         if (!tunsec)
5596                 return -ENOMEM;
5597         tunsec->sid = current_sid();
5598
5599         *security = tunsec;
5600         return 0;
5601 }
5602
5603 static void selinux_tun_dev_free_security(void *security)
5604 {
5605         kfree(security);
5606 }
5607
5608 static int selinux_tun_dev_create(void)
5609 {
5610         u32 sid = current_sid();
5611
5612         /* we aren't taking into account the "sockcreate" SID since the socket
5613          * that is being created here is not a socket in the traditional sense,
5614          * instead it is a private sock, accessible only to the kernel, and
5615          * representing a wide range of network traffic spanning multiple
5616          * connections unlike traditional sockets - check the TUN driver to
5617          * get a better understanding of why this socket is special */
5618
5619         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5620                             NULL);
5621 }
5622
5623 static int selinux_tun_dev_attach_queue(void *security)
5624 {
5625         struct tun_security_struct *tunsec = security;
5626
5627         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5628                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5629 }
5630
5631 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5632 {
5633         struct tun_security_struct *tunsec = security;
5634         struct sk_security_struct *sksec = sk->sk_security;
5635
5636         /* we don't currently perform any NetLabel based labeling here and it
5637          * isn't clear that we would want to do so anyway; while we could apply
5638          * labeling without the support of the TUN user the resulting labeled
5639          * traffic from the other end of the connection would almost certainly
5640          * cause confusion to the TUN user that had no idea network labeling
5641          * protocols were being used */
5642
5643         sksec->sid = tunsec->sid;
5644         sksec->sclass = SECCLASS_TUN_SOCKET;
5645
5646         return 0;
5647 }
5648
5649 static int selinux_tun_dev_open(void *security)
5650 {
5651         struct tun_security_struct *tunsec = security;
5652         u32 sid = current_sid();
5653         int err;
5654
5655         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5656                            TUN_SOCKET__RELABELFROM, NULL);
5657         if (err)
5658                 return err;
5659         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5660                            TUN_SOCKET__RELABELTO, NULL);
5661         if (err)
5662                 return err;
5663         tunsec->sid = sid;
5664
5665         return 0;
5666 }
5667
5668 #ifdef CONFIG_NETFILTER
5669
5670 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5671                                        const struct nf_hook_state *state)
5672 {
5673         int ifindex;
5674         u16 family;
5675         char *addrp;
5676         u32 peer_sid;
5677         struct common_audit_data ad;
5678         struct lsm_network_audit net;
5679         int secmark_active, peerlbl_active;
5680
5681         if (!selinux_policycap_netpeer())
5682                 return NF_ACCEPT;
5683
5684         secmark_active = selinux_secmark_enabled();
5685         peerlbl_active = selinux_peerlbl_enabled();
5686         if (!secmark_active && !peerlbl_active)
5687                 return NF_ACCEPT;
5688
5689         family = state->pf;
5690         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5691                 return NF_DROP;
5692
5693         ifindex = state->in->ifindex;
5694         ad_net_init_from_iif(&ad, &net, ifindex, family);
5695         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5696                 return NF_DROP;
5697
5698         if (peerlbl_active) {
5699                 int err;
5700
5701                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5702                                                addrp, family, peer_sid, &ad);
5703                 if (err) {
5704                         selinux_netlbl_err(skb, family, err, 1);
5705                         return NF_DROP;
5706                 }
5707         }
5708
5709         if (secmark_active)
5710                 if (avc_has_perm(peer_sid, skb->secmark,
5711                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5712                         return NF_DROP;
5713
5714         if (netlbl_enabled())
5715                 /* we do this in the FORWARD path and not the POST_ROUTING
5716                  * path because we want to make sure we apply the necessary
5717                  * labeling before IPsec is applied so we can leverage AH
5718                  * protection */
5719                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5720                         return NF_DROP;
5721
5722         return NF_ACCEPT;
5723 }
5724
5725 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5726                                       const struct nf_hook_state *state)
5727 {
5728         struct sock *sk;
5729         u32 sid;
5730
5731         if (!netlbl_enabled())
5732                 return NF_ACCEPT;
5733
5734         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5735          * because we want to make sure we apply the necessary labeling
5736          * before IPsec is applied so we can leverage AH protection */
5737         sk = skb->sk;
5738         if (sk) {
5739                 struct sk_security_struct *sksec;
5740
5741                 if (sk_listener(sk))
5742                         /* if the socket is the listening state then this
5743                          * packet is a SYN-ACK packet which means it needs to
5744                          * be labeled based on the connection/request_sock and
5745                          * not the parent socket.  unfortunately, we can't
5746                          * lookup the request_sock yet as it isn't queued on
5747                          * the parent socket until after the SYN-ACK is sent.
5748                          * the "solution" is to simply pass the packet as-is
5749                          * as any IP option based labeling should be copied
5750                          * from the initial connection request (in the IP
5751                          * layer).  it is far from ideal, but until we get a
5752                          * security label in the packet itself this is the
5753                          * best we can do. */
5754                         return NF_ACCEPT;
5755
5756                 /* standard practice, label using the parent socket */
5757                 sksec = sk->sk_security;
5758                 sid = sksec->sid;
5759         } else
5760                 sid = SECINITSID_KERNEL;
5761         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5762                 return NF_DROP;
5763
5764         return NF_ACCEPT;
5765 }
5766
5767
5768 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5769                                         const struct nf_hook_state *state)
5770 {
5771         struct sock *sk;
5772         struct sk_security_struct *sksec;
5773         struct common_audit_data ad;
5774         struct lsm_network_audit net;
5775         u8 proto = 0;
5776
5777         sk = skb_to_full_sk(skb);
5778         if (sk == NULL)
5779                 return NF_ACCEPT;
5780         sksec = sk->sk_security;
5781
5782         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5783         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5784                 return NF_DROP;
5785
5786         if (selinux_secmark_enabled())
5787                 if (avc_has_perm(sksec->sid, skb->secmark,
5788                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5789                         return NF_DROP_ERR(-ECONNREFUSED);
5790
5791         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5792                 return NF_DROP_ERR(-ECONNREFUSED);
5793
5794         return NF_ACCEPT;
5795 }
5796
5797 static unsigned int selinux_ip_postroute(void *priv,
5798                                          struct sk_buff *skb,
5799                                          const struct nf_hook_state *state)
5800 {
5801         u16 family;
5802         u32 secmark_perm;
5803         u32 peer_sid;
5804         int ifindex;
5805         struct sock *sk;
5806         struct common_audit_data ad;
5807         struct lsm_network_audit net;
5808         char *addrp;
5809         int secmark_active, peerlbl_active;
5810
5811         /* If any sort of compatibility mode is enabled then handoff processing
5812          * to the selinux_ip_postroute_compat() function to deal with the
5813          * special handling.  We do this in an attempt to keep this function
5814          * as fast and as clean as possible. */
5815         if (!selinux_policycap_netpeer())
5816                 return selinux_ip_postroute_compat(skb, state);
5817
5818         secmark_active = selinux_secmark_enabled();
5819         peerlbl_active = selinux_peerlbl_enabled();
5820         if (!secmark_active && !peerlbl_active)
5821                 return NF_ACCEPT;
5822
5823         sk = skb_to_full_sk(skb);
5824
5825 #ifdef CONFIG_XFRM
5826         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5827          * packet transformation so allow the packet to pass without any checks
5828          * since we'll have another chance to perform access control checks
5829          * when the packet is on it's final way out.
5830          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5831          *       is NULL, in this case go ahead and apply access control.
5832          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5833          *       TCP listening state we cannot wait until the XFRM processing
5834          *       is done as we will miss out on the SA label if we do;
5835          *       unfortunately, this means more work, but it is only once per
5836          *       connection. */
5837         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5838             !(sk && sk_listener(sk)))
5839                 return NF_ACCEPT;
5840 #endif
5841
5842         family = state->pf;
5843         if (sk == NULL) {
5844                 /* Without an associated socket the packet is either coming
5845                  * from the kernel or it is being forwarded; check the packet
5846                  * to determine which and if the packet is being forwarded
5847                  * query the packet directly to determine the security label. */
5848                 if (skb->skb_iif) {
5849                         secmark_perm = PACKET__FORWARD_OUT;
5850                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5851                                 return NF_DROP;
5852                 } else {
5853                         secmark_perm = PACKET__SEND;
5854                         peer_sid = SECINITSID_KERNEL;
5855                 }
5856         } else if (sk_listener(sk)) {
5857                 /* Locally generated packet but the associated socket is in the
5858                  * listening state which means this is a SYN-ACK packet.  In
5859                  * this particular case the correct security label is assigned
5860                  * to the connection/request_sock but unfortunately we can't
5861                  * query the request_sock as it isn't queued on the parent
5862                  * socket until after the SYN-ACK packet is sent; the only
5863                  * viable choice is to regenerate the label like we do in
5864                  * selinux_inet_conn_request().  See also selinux_ip_output()
5865                  * for similar problems. */
5866                 u32 skb_sid;
5867                 struct sk_security_struct *sksec;
5868
5869                 sksec = sk->sk_security;
5870                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5871                         return NF_DROP;
5872                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5873                  * and the packet has been through at least one XFRM
5874                  * transformation then we must be dealing with the "final"
5875                  * form of labeled IPsec packet; since we've already applied
5876                  * all of our access controls on this packet we can safely
5877                  * pass the packet. */
5878                 if (skb_sid == SECSID_NULL) {
5879                         switch (family) {
5880                         case PF_INET:
5881                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5882                                         return NF_ACCEPT;
5883                                 break;
5884                         case PF_INET6:
5885                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5886                                         return NF_ACCEPT;
5887                                 break;
5888                         default:
5889                                 return NF_DROP_ERR(-ECONNREFUSED);
5890                         }
5891                 }
5892                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5893                         return NF_DROP;
5894                 secmark_perm = PACKET__SEND;
5895         } else {
5896                 /* Locally generated packet, fetch the security label from the
5897                  * associated socket. */
5898                 struct sk_security_struct *sksec = sk->sk_security;
5899                 peer_sid = sksec->sid;
5900                 secmark_perm = PACKET__SEND;
5901         }
5902
5903         ifindex = state->out->ifindex;
5904         ad_net_init_from_iif(&ad, &net, ifindex, family);
5905         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5906                 return NF_DROP;
5907
5908         if (secmark_active)
5909                 if (avc_has_perm(peer_sid, skb->secmark,
5910                                  SECCLASS_PACKET, secmark_perm, &ad))
5911                         return NF_DROP_ERR(-ECONNREFUSED);
5912
5913         if (peerlbl_active) {
5914                 u32 if_sid;
5915                 u32 node_sid;
5916
5917                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5918                         return NF_DROP;
5919                 if (avc_has_perm(peer_sid, if_sid,
5920                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5921                         return NF_DROP_ERR(-ECONNREFUSED);
5922
5923                 if (sel_netnode_sid(addrp, family, &node_sid))
5924                         return NF_DROP;
5925                 if (avc_has_perm(peer_sid, node_sid,
5926                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5927                         return NF_DROP_ERR(-ECONNREFUSED);
5928         }
5929
5930         return NF_ACCEPT;
5931 }
5932 #endif  /* CONFIG_NETFILTER */
5933
5934 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5935 {
5936         int rc = 0;
5937         unsigned int msg_len;
5938         unsigned int data_len = skb->len;
5939         unsigned char *data = skb->data;
5940         struct nlmsghdr *nlh;
5941         struct sk_security_struct *sksec = sk->sk_security;
5942         u16 sclass = sksec->sclass;
5943         u32 perm;
5944
5945         while (data_len >= nlmsg_total_size(0)) {
5946                 nlh = (struct nlmsghdr *)data;
5947
5948                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5949                  *       users which means we can't reject skb's with bogus
5950                  *       length fields; our solution is to follow what
5951                  *       netlink_rcv_skb() does and simply skip processing at
5952                  *       messages with length fields that are clearly junk
5953                  */
5954                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5955                         return 0;
5956
5957                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5958                 if (rc == 0) {
5959                         rc = sock_has_perm(sk, perm);
5960                         if (rc)
5961                                 return rc;
5962                 } else if (rc == -EINVAL) {
5963                         /* -EINVAL is a missing msg/perm mapping */
5964                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5965                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5966                                 " pid=%d comm=%s\n",
5967                                 sk->sk_protocol, nlh->nlmsg_type,
5968                                 secclass_map[sclass - 1].name,
5969                                 task_pid_nr(current), current->comm);
5970                         if (enforcing_enabled() &&
5971                             !security_get_allow_unknown())
5972                                 return rc;
5973                         rc = 0;
5974                 } else if (rc == -ENOENT) {
5975                         /* -ENOENT is a missing socket/class mapping, ignore */
5976                         rc = 0;
5977                 } else {
5978                         return rc;
5979                 }
5980
5981                 /* move to the next message after applying netlink padding */
5982                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5983                 if (msg_len >= data_len)
5984                         return 0;
5985                 data_len -= msg_len;
5986                 data += msg_len;
5987         }
5988
5989         return rc;
5990 }
5991
5992 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5993 {
5994         isec->sclass = sclass;
5995         isec->sid = current_sid();
5996 }
5997
5998 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5999                         u32 perms)
6000 {
6001         struct ipc_security_struct *isec;
6002         struct common_audit_data ad;
6003         u32 sid = current_sid();
6004
6005         isec = selinux_ipc(ipc_perms);
6006
6007         ad.type = LSM_AUDIT_DATA_IPC;
6008         ad.u.ipc_id = ipc_perms->key;
6009
6010         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6011 }
6012
6013 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6014 {
6015         struct msg_security_struct *msec;
6016
6017         msec = selinux_msg_msg(msg);
6018         msec->sid = SECINITSID_UNLABELED;
6019
6020         return 0;
6021 }
6022
6023 /* message queue security operations */
6024 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6025 {
6026         struct ipc_security_struct *isec;
6027         struct common_audit_data ad;
6028         u32 sid = current_sid();
6029
6030         isec = selinux_ipc(msq);
6031         ipc_init_security(isec, SECCLASS_MSGQ);
6032
6033         ad.type = LSM_AUDIT_DATA_IPC;
6034         ad.u.ipc_id = msq->key;
6035
6036         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6037                             MSGQ__CREATE, &ad);
6038 }
6039
6040 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6041 {
6042         struct ipc_security_struct *isec;
6043         struct common_audit_data ad;
6044         u32 sid = current_sid();
6045
6046         isec = selinux_ipc(msq);
6047
6048         ad.type = LSM_AUDIT_DATA_IPC;
6049         ad.u.ipc_id = msq->key;
6050
6051         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6052                             MSGQ__ASSOCIATE, &ad);
6053 }
6054
6055 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6056 {
6057         u32 perms;
6058
6059         switch (cmd) {
6060         case IPC_INFO:
6061         case MSG_INFO:
6062                 /* No specific object, just general system-wide information. */
6063                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6064                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6065         case IPC_STAT:
6066         case MSG_STAT:
6067         case MSG_STAT_ANY:
6068                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6069                 break;
6070         case IPC_SET:
6071                 perms = MSGQ__SETATTR;
6072                 break;
6073         case IPC_RMID:
6074                 perms = MSGQ__DESTROY;
6075                 break;
6076         default:
6077                 return 0;
6078         }
6079
6080         return ipc_has_perm(msq, perms);
6081 }
6082
6083 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6084 {
6085         struct ipc_security_struct *isec;
6086         struct msg_security_struct *msec;
6087         struct common_audit_data ad;
6088         u32 sid = current_sid();
6089         int rc;
6090
6091         isec = selinux_ipc(msq);
6092         msec = selinux_msg_msg(msg);
6093
6094         /*
6095          * First time through, need to assign label to the message
6096          */
6097         if (msec->sid == SECINITSID_UNLABELED) {
6098                 /*
6099                  * Compute new sid based on current process and
6100                  * message queue this message will be stored in
6101                  */
6102                 rc = security_transition_sid(sid, isec->sid,
6103                                              SECCLASS_MSG, NULL, &msec->sid);
6104                 if (rc)
6105                         return rc;
6106         }
6107
6108         ad.type = LSM_AUDIT_DATA_IPC;
6109         ad.u.ipc_id = msq->key;
6110
6111         /* Can this process write to the queue? */
6112         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6113                           MSGQ__WRITE, &ad);
6114         if (!rc)
6115                 /* Can this process send the message */
6116                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6117                                   MSG__SEND, &ad);
6118         if (!rc)
6119                 /* Can the message be put in the queue? */
6120                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6121                                   MSGQ__ENQUEUE, &ad);
6122
6123         return rc;
6124 }
6125
6126 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6127                                     struct task_struct *target,
6128                                     long type, int mode)
6129 {
6130         struct ipc_security_struct *isec;
6131         struct msg_security_struct *msec;
6132         struct common_audit_data ad;
6133         u32 sid = task_sid_obj(target);
6134         int rc;
6135
6136         isec = selinux_ipc(msq);
6137         msec = selinux_msg_msg(msg);
6138
6139         ad.type = LSM_AUDIT_DATA_IPC;
6140         ad.u.ipc_id = msq->key;
6141
6142         rc = avc_has_perm(sid, isec->sid,
6143                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6144         if (!rc)
6145                 rc = avc_has_perm(sid, msec->sid,
6146                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6147         return rc;
6148 }
6149
6150 /* Shared Memory security operations */
6151 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6152 {
6153         struct ipc_security_struct *isec;
6154         struct common_audit_data ad;
6155         u32 sid = current_sid();
6156
6157         isec = selinux_ipc(shp);
6158         ipc_init_security(isec, SECCLASS_SHM);
6159
6160         ad.type = LSM_AUDIT_DATA_IPC;
6161         ad.u.ipc_id = shp->key;
6162
6163         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6164                             SHM__CREATE, &ad);
6165 }
6166
6167 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6168 {
6169         struct ipc_security_struct *isec;
6170         struct common_audit_data ad;
6171         u32 sid = current_sid();
6172
6173         isec = selinux_ipc(shp);
6174
6175         ad.type = LSM_AUDIT_DATA_IPC;
6176         ad.u.ipc_id = shp->key;
6177
6178         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6179                             SHM__ASSOCIATE, &ad);
6180 }
6181
6182 /* Note, at this point, shp is locked down */
6183 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6184 {
6185         u32 perms;
6186
6187         switch (cmd) {
6188         case IPC_INFO:
6189         case SHM_INFO:
6190                 /* No specific object, just general system-wide information. */
6191                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6192                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6193         case IPC_STAT:
6194         case SHM_STAT:
6195         case SHM_STAT_ANY:
6196                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6197                 break;
6198         case IPC_SET:
6199                 perms = SHM__SETATTR;
6200                 break;
6201         case SHM_LOCK:
6202         case SHM_UNLOCK:
6203                 perms = SHM__LOCK;
6204                 break;
6205         case IPC_RMID:
6206                 perms = SHM__DESTROY;
6207                 break;
6208         default:
6209                 return 0;
6210         }
6211
6212         return ipc_has_perm(shp, perms);
6213 }
6214
6215 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6216                              char __user *shmaddr, int shmflg)
6217 {
6218         u32 perms;
6219
6220         if (shmflg & SHM_RDONLY)
6221                 perms = SHM__READ;
6222         else
6223                 perms = SHM__READ | SHM__WRITE;
6224
6225         return ipc_has_perm(shp, perms);
6226 }
6227
6228 /* Semaphore security operations */
6229 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6230 {
6231         struct ipc_security_struct *isec;
6232         struct common_audit_data ad;
6233         u32 sid = current_sid();
6234
6235         isec = selinux_ipc(sma);
6236         ipc_init_security(isec, SECCLASS_SEM);
6237
6238         ad.type = LSM_AUDIT_DATA_IPC;
6239         ad.u.ipc_id = sma->key;
6240
6241         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6242                             SEM__CREATE, &ad);
6243 }
6244
6245 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6246 {
6247         struct ipc_security_struct *isec;
6248         struct common_audit_data ad;
6249         u32 sid = current_sid();
6250
6251         isec = selinux_ipc(sma);
6252
6253         ad.type = LSM_AUDIT_DATA_IPC;
6254         ad.u.ipc_id = sma->key;
6255
6256         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6257                             SEM__ASSOCIATE, &ad);
6258 }
6259
6260 /* Note, at this point, sma is locked down */
6261 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6262 {
6263         int err;
6264         u32 perms;
6265
6266         switch (cmd) {
6267         case IPC_INFO:
6268         case SEM_INFO:
6269                 /* No specific object, just general system-wide information. */
6270                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6271                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6272         case GETPID:
6273         case GETNCNT:
6274         case GETZCNT:
6275                 perms = SEM__GETATTR;
6276                 break;
6277         case GETVAL:
6278         case GETALL:
6279                 perms = SEM__READ;
6280                 break;
6281         case SETVAL:
6282         case SETALL:
6283                 perms = SEM__WRITE;
6284                 break;
6285         case IPC_RMID:
6286                 perms = SEM__DESTROY;
6287                 break;
6288         case IPC_SET:
6289                 perms = SEM__SETATTR;
6290                 break;
6291         case IPC_STAT:
6292         case SEM_STAT:
6293         case SEM_STAT_ANY:
6294                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6295                 break;
6296         default:
6297                 return 0;
6298         }
6299
6300         err = ipc_has_perm(sma, perms);
6301         return err;
6302 }
6303
6304 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6305                              struct sembuf *sops, unsigned nsops, int alter)
6306 {
6307         u32 perms;
6308
6309         if (alter)
6310                 perms = SEM__READ | SEM__WRITE;
6311         else
6312                 perms = SEM__READ;
6313
6314         return ipc_has_perm(sma, perms);
6315 }
6316
6317 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6318 {
6319         u32 av = 0;
6320
6321         av = 0;
6322         if (flag & S_IRUGO)
6323                 av |= IPC__UNIX_READ;
6324         if (flag & S_IWUGO)
6325                 av |= IPC__UNIX_WRITE;
6326
6327         if (av == 0)
6328                 return 0;
6329
6330         return ipc_has_perm(ipcp, av);
6331 }
6332
6333 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6334 {
6335         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6336         *secid = isec->sid;
6337 }
6338
6339 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6340 {
6341         if (inode)
6342                 inode_doinit_with_dentry(inode, dentry);
6343 }
6344
6345 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6346                                char **value)
6347 {
6348         const struct task_security_struct *__tsec;
6349         u32 sid;
6350         int error;
6351         unsigned len;
6352
6353         rcu_read_lock();
6354         __tsec = selinux_cred(__task_cred(p));
6355
6356         if (current != p) {
6357                 error = avc_has_perm(current_sid(), __tsec->sid,
6358                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6359                 if (error)
6360                         goto bad;
6361         }
6362
6363         switch (attr) {
6364         case LSM_ATTR_CURRENT:
6365                 sid = __tsec->sid;
6366                 break;
6367         case LSM_ATTR_PREV:
6368                 sid = __tsec->osid;
6369                 break;
6370         case LSM_ATTR_EXEC:
6371                 sid = __tsec->exec_sid;
6372                 break;
6373         case LSM_ATTR_FSCREATE:
6374                 sid = __tsec->create_sid;
6375                 break;
6376         case LSM_ATTR_KEYCREATE:
6377                 sid = __tsec->keycreate_sid;
6378                 break;
6379         case LSM_ATTR_SOCKCREATE:
6380                 sid = __tsec->sockcreate_sid;
6381                 break;
6382         default:
6383                 error = -EOPNOTSUPP;
6384                 goto bad;
6385         }
6386         rcu_read_unlock();
6387
6388         if (!sid)
6389                 return 0;
6390
6391         error = security_sid_to_context(sid, value, &len);
6392         if (error)
6393                 return error;
6394         return len;
6395
6396 bad:
6397         rcu_read_unlock();
6398         return error;
6399 }
6400
6401 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6402 {
6403         struct task_security_struct *tsec;
6404         struct cred *new;
6405         u32 mysid = current_sid(), sid = 0, ptsid;
6406         int error;
6407         char *str = value;
6408
6409         /*
6410          * Basic control over ability to set these attributes at all.
6411          */
6412         switch (attr) {
6413         case LSM_ATTR_EXEC:
6414                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6415                                      PROCESS__SETEXEC, NULL);
6416                 break;
6417         case LSM_ATTR_FSCREATE:
6418                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6419                                      PROCESS__SETFSCREATE, NULL);
6420                 break;
6421         case LSM_ATTR_KEYCREATE:
6422                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6423                                      PROCESS__SETKEYCREATE, NULL);
6424                 break;
6425         case LSM_ATTR_SOCKCREATE:
6426                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6427                                      PROCESS__SETSOCKCREATE, NULL);
6428                 break;
6429         case LSM_ATTR_CURRENT:
6430                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6431                                      PROCESS__SETCURRENT, NULL);
6432                 break;
6433         default:
6434                 error = -EOPNOTSUPP;
6435                 break;
6436         }
6437         if (error)
6438                 return error;
6439
6440         /* Obtain a SID for the context, if one was specified. */
6441         if (size && str[0] && str[0] != '\n') {
6442                 if (str[size-1] == '\n') {
6443                         str[size-1] = 0;
6444                         size--;
6445                 }
6446                 error = security_context_to_sid(value, size,
6447                                                 &sid, GFP_KERNEL);
6448                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6449                         if (!has_cap_mac_admin(true)) {
6450                                 struct audit_buffer *ab;
6451                                 size_t audit_size;
6452
6453                                 /* We strip a nul only if it is at the end,
6454                                  * otherwise the context contains a nul and
6455                                  * we should audit that */
6456                                 if (str[size - 1] == '\0')
6457                                         audit_size = size - 1;
6458                                 else
6459                                         audit_size = size;
6460                                 ab = audit_log_start(audit_context(),
6461                                                      GFP_ATOMIC,
6462                                                      AUDIT_SELINUX_ERR);
6463                                 if (!ab)
6464                                         return error;
6465                                 audit_log_format(ab, "op=fscreate invalid_context=");
6466                                 audit_log_n_untrustedstring(ab, value,
6467                                                             audit_size);
6468                                 audit_log_end(ab);
6469
6470                                 return error;
6471                         }
6472                         error = security_context_to_sid_force(value, size,
6473                                                         &sid);
6474                 }
6475                 if (error)
6476                         return error;
6477         }
6478
6479         new = prepare_creds();
6480         if (!new)
6481                 return -ENOMEM;
6482
6483         /* Permission checking based on the specified context is
6484            performed during the actual operation (execve,
6485            open/mkdir/...), when we know the full context of the
6486            operation.  See selinux_bprm_creds_for_exec for the execve
6487            checks and may_create for the file creation checks. The
6488            operation will then fail if the context is not permitted. */
6489         tsec = selinux_cred(new);
6490         if (attr == LSM_ATTR_EXEC) {
6491                 tsec->exec_sid = sid;
6492         } else if (attr == LSM_ATTR_FSCREATE) {
6493                 tsec->create_sid = sid;
6494         } else if (attr == LSM_ATTR_KEYCREATE) {
6495                 if (sid) {
6496                         error = avc_has_perm(mysid, sid,
6497                                              SECCLASS_KEY, KEY__CREATE, NULL);
6498                         if (error)
6499                                 goto abort_change;
6500                 }
6501                 tsec->keycreate_sid = sid;
6502         } else if (attr == LSM_ATTR_SOCKCREATE) {
6503                 tsec->sockcreate_sid = sid;
6504         } else if (attr == LSM_ATTR_CURRENT) {
6505                 error = -EINVAL;
6506                 if (sid == 0)
6507                         goto abort_change;
6508
6509                 if (!current_is_single_threaded()) {
6510                         error = security_bounded_transition(tsec->sid, sid);
6511                         if (error)
6512                                 goto abort_change;
6513                 }
6514
6515                 /* Check permissions for the transition. */
6516                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6517                                      PROCESS__DYNTRANSITION, NULL);
6518                 if (error)
6519                         goto abort_change;
6520
6521                 /* Check for ptracing, and update the task SID if ok.
6522                    Otherwise, leave SID unchanged and fail. */
6523                 ptsid = ptrace_parent_sid();
6524                 if (ptsid != 0) {
6525                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6526                                              PROCESS__PTRACE, NULL);
6527                         if (error)
6528                                 goto abort_change;
6529                 }
6530
6531                 tsec->sid = sid;
6532         } else {
6533                 error = -EINVAL;
6534                 goto abort_change;
6535         }
6536
6537         commit_creds(new);
6538         return size;
6539
6540 abort_change:
6541         abort_creds(new);
6542         return error;
6543 }
6544
6545 /**
6546  * selinux_getselfattr - Get SELinux current task attributes
6547  * @attr: the requested attribute
6548  * @ctx: buffer to receive the result
6549  * @size: buffer size (input), buffer size used (output)
6550  * @flags: unused
6551  *
6552  * Fill the passed user space @ctx with the details of the requested
6553  * attribute.
6554  *
6555  * Returns the number of attributes on success, an error code otherwise.
6556  * There will only ever be one attribute.
6557  */
6558 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6559                                size_t *size, u32 flags)
6560 {
6561         int rc;
6562         char *val = NULL;
6563         int val_len;
6564
6565         val_len = selinux_lsm_getattr(attr, current, &val);
6566         if (val_len < 0)
6567                 return val_len;
6568         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6569         kfree(val);
6570         return (!rc ? 1 : rc);
6571 }
6572
6573 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6574                                size_t size, u32 flags)
6575 {
6576         int rc;
6577
6578         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6579         if (rc > 0)
6580                 return 0;
6581         return rc;
6582 }
6583
6584 static int selinux_getprocattr(struct task_struct *p,
6585                                const char *name, char **value)
6586 {
6587         unsigned int attr = lsm_name_to_attr(name);
6588         int rc;
6589
6590         if (attr) {
6591                 rc = selinux_lsm_getattr(attr, p, value);
6592                 if (rc != -EOPNOTSUPP)
6593                         return rc;
6594         }
6595
6596         return -EINVAL;
6597 }
6598
6599 static int selinux_setprocattr(const char *name, void *value, size_t size)
6600 {
6601         int attr = lsm_name_to_attr(name);
6602
6603         if (attr)
6604                 return selinux_lsm_setattr(attr, value, size);
6605         return -EINVAL;
6606 }
6607
6608 static int selinux_ismaclabel(const char *name)
6609 {
6610         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6611 }
6612
6613 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6614 {
6615         return security_sid_to_context(secid,
6616                                        secdata, seclen);
6617 }
6618
6619 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6620 {
6621         return security_context_to_sid(secdata, seclen,
6622                                        secid, GFP_KERNEL);
6623 }
6624
6625 static void selinux_release_secctx(char *secdata, u32 seclen)
6626 {
6627         kfree(secdata);
6628 }
6629
6630 static void selinux_inode_invalidate_secctx(struct inode *inode)
6631 {
6632         struct inode_security_struct *isec = selinux_inode(inode);
6633
6634         spin_lock(&isec->lock);
6635         isec->initialized = LABEL_INVALID;
6636         spin_unlock(&isec->lock);
6637 }
6638
6639 /*
6640  *      called with inode->i_mutex locked
6641  */
6642 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6643 {
6644         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6645                                            ctx, ctxlen, 0);
6646         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6647         return rc == -EOPNOTSUPP ? 0 : rc;
6648 }
6649
6650 /*
6651  *      called with inode->i_mutex locked
6652  */
6653 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6654 {
6655         return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6656                                      ctx, ctxlen, 0);
6657 }
6658
6659 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6660 {
6661         int len = 0;
6662         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6663                                         XATTR_SELINUX_SUFFIX, ctx, true);
6664         if (len < 0)
6665                 return len;
6666         *ctxlen = len;
6667         return 0;
6668 }
6669 #ifdef CONFIG_KEYS
6670
6671 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6672                              unsigned long flags)
6673 {
6674         const struct task_security_struct *tsec;
6675         struct key_security_struct *ksec;
6676
6677         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6678         if (!ksec)
6679                 return -ENOMEM;
6680
6681         tsec = selinux_cred(cred);
6682         if (tsec->keycreate_sid)
6683                 ksec->sid = tsec->keycreate_sid;
6684         else
6685                 ksec->sid = tsec->sid;
6686
6687         k->security = ksec;
6688         return 0;
6689 }
6690
6691 static void selinux_key_free(struct key *k)
6692 {
6693         struct key_security_struct *ksec = k->security;
6694
6695         k->security = NULL;
6696         kfree(ksec);
6697 }
6698
6699 static int selinux_key_permission(key_ref_t key_ref,
6700                                   const struct cred *cred,
6701                                   enum key_need_perm need_perm)
6702 {
6703         struct key *key;
6704         struct key_security_struct *ksec;
6705         u32 perm, sid;
6706
6707         switch (need_perm) {
6708         case KEY_NEED_VIEW:
6709                 perm = KEY__VIEW;
6710                 break;
6711         case KEY_NEED_READ:
6712                 perm = KEY__READ;
6713                 break;
6714         case KEY_NEED_WRITE:
6715                 perm = KEY__WRITE;
6716                 break;
6717         case KEY_NEED_SEARCH:
6718                 perm = KEY__SEARCH;
6719                 break;
6720         case KEY_NEED_LINK:
6721                 perm = KEY__LINK;
6722                 break;
6723         case KEY_NEED_SETATTR:
6724                 perm = KEY__SETATTR;
6725                 break;
6726         case KEY_NEED_UNLINK:
6727         case KEY_SYSADMIN_OVERRIDE:
6728         case KEY_AUTHTOKEN_OVERRIDE:
6729         case KEY_DEFER_PERM_CHECK:
6730                 return 0;
6731         default:
6732                 WARN_ON(1);
6733                 return -EPERM;
6734
6735         }
6736
6737         sid = cred_sid(cred);
6738         key = key_ref_to_ptr(key_ref);
6739         ksec = key->security;
6740
6741         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6742 }
6743
6744 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6745 {
6746         struct key_security_struct *ksec = key->security;
6747         char *context = NULL;
6748         unsigned len;
6749         int rc;
6750
6751         rc = security_sid_to_context(ksec->sid,
6752                                      &context, &len);
6753         if (!rc)
6754                 rc = len;
6755         *_buffer = context;
6756         return rc;
6757 }
6758
6759 #ifdef CONFIG_KEY_NOTIFICATIONS
6760 static int selinux_watch_key(struct key *key)
6761 {
6762         struct key_security_struct *ksec = key->security;
6763         u32 sid = current_sid();
6764
6765         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6766 }
6767 #endif
6768 #endif
6769
6770 #ifdef CONFIG_SECURITY_INFINIBAND
6771 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6772 {
6773         struct common_audit_data ad;
6774         int err;
6775         u32 sid = 0;
6776         struct ib_security_struct *sec = ib_sec;
6777         struct lsm_ibpkey_audit ibpkey;
6778
6779         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6780         if (err)
6781                 return err;
6782
6783         ad.type = LSM_AUDIT_DATA_IBPKEY;
6784         ibpkey.subnet_prefix = subnet_prefix;
6785         ibpkey.pkey = pkey_val;
6786         ad.u.ibpkey = &ibpkey;
6787         return avc_has_perm(sec->sid, sid,
6788                             SECCLASS_INFINIBAND_PKEY,
6789                             INFINIBAND_PKEY__ACCESS, &ad);
6790 }
6791
6792 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6793                                             u8 port_num)
6794 {
6795         struct common_audit_data ad;
6796         int err;
6797         u32 sid = 0;
6798         struct ib_security_struct *sec = ib_sec;
6799         struct lsm_ibendport_audit ibendport;
6800
6801         err = security_ib_endport_sid(dev_name, port_num,
6802                                       &sid);
6803
6804         if (err)
6805                 return err;
6806
6807         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6808         ibendport.dev_name = dev_name;
6809         ibendport.port = port_num;
6810         ad.u.ibendport = &ibendport;
6811         return avc_has_perm(sec->sid, sid,
6812                             SECCLASS_INFINIBAND_ENDPORT,
6813                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6814 }
6815
6816 static int selinux_ib_alloc_security(void **ib_sec)
6817 {
6818         struct ib_security_struct *sec;
6819
6820         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6821         if (!sec)
6822                 return -ENOMEM;
6823         sec->sid = current_sid();
6824
6825         *ib_sec = sec;
6826         return 0;
6827 }
6828
6829 static void selinux_ib_free_security(void *ib_sec)
6830 {
6831         kfree(ib_sec);
6832 }
6833 #endif
6834
6835 #ifdef CONFIG_BPF_SYSCALL
6836 static int selinux_bpf(int cmd, union bpf_attr *attr,
6837                                      unsigned int size)
6838 {
6839         u32 sid = current_sid();
6840         int ret;
6841
6842         switch (cmd) {
6843         case BPF_MAP_CREATE:
6844                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6845                                    NULL);
6846                 break;
6847         case BPF_PROG_LOAD:
6848                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6849                                    NULL);
6850                 break;
6851         default:
6852                 ret = 0;
6853                 break;
6854         }
6855
6856         return ret;
6857 }
6858
6859 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6860 {
6861         u32 av = 0;
6862
6863         if (fmode & FMODE_READ)
6864                 av |= BPF__MAP_READ;
6865         if (fmode & FMODE_WRITE)
6866                 av |= BPF__MAP_WRITE;
6867         return av;
6868 }
6869
6870 /* This function will check the file pass through unix socket or binder to see
6871  * if it is a bpf related object. And apply corresponding checks on the bpf
6872  * object based on the type. The bpf maps and programs, not like other files and
6873  * socket, are using a shared anonymous inode inside the kernel as their inode.
6874  * So checking that inode cannot identify if the process have privilege to
6875  * access the bpf object and that's why we have to add this additional check in
6876  * selinux_file_receive and selinux_binder_transfer_files.
6877  */
6878 static int bpf_fd_pass(const struct file *file, u32 sid)
6879 {
6880         struct bpf_security_struct *bpfsec;
6881         struct bpf_prog *prog;
6882         struct bpf_map *map;
6883         int ret;
6884
6885         if (file->f_op == &bpf_map_fops) {
6886                 map = file->private_data;
6887                 bpfsec = map->security;
6888                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6889                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6890                 if (ret)
6891                         return ret;
6892         } else if (file->f_op == &bpf_prog_fops) {
6893                 prog = file->private_data;
6894                 bpfsec = prog->aux->security;
6895                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6896                                    BPF__PROG_RUN, NULL);
6897                 if (ret)
6898                         return ret;
6899         }
6900         return 0;
6901 }
6902
6903 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6904 {
6905         u32 sid = current_sid();
6906         struct bpf_security_struct *bpfsec;
6907
6908         bpfsec = map->security;
6909         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6910                             bpf_map_fmode_to_av(fmode), NULL);
6911 }
6912
6913 static int selinux_bpf_prog(struct bpf_prog *prog)
6914 {
6915         u32 sid = current_sid();
6916         struct bpf_security_struct *bpfsec;
6917
6918         bpfsec = prog->aux->security;
6919         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6920                             BPF__PROG_RUN, NULL);
6921 }
6922
6923 static int selinux_bpf_map_alloc(struct bpf_map *map)
6924 {
6925         struct bpf_security_struct *bpfsec;
6926
6927         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6928         if (!bpfsec)
6929                 return -ENOMEM;
6930
6931         bpfsec->sid = current_sid();
6932         map->security = bpfsec;
6933
6934         return 0;
6935 }
6936
6937 static void selinux_bpf_map_free(struct bpf_map *map)
6938 {
6939         struct bpf_security_struct *bpfsec = map->security;
6940
6941         map->security = NULL;
6942         kfree(bpfsec);
6943 }
6944
6945 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6946 {
6947         struct bpf_security_struct *bpfsec;
6948
6949         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6950         if (!bpfsec)
6951                 return -ENOMEM;
6952
6953         bpfsec->sid = current_sid();
6954         aux->security = bpfsec;
6955
6956         return 0;
6957 }
6958
6959 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6960 {
6961         struct bpf_security_struct *bpfsec = aux->security;
6962
6963         aux->security = NULL;
6964         kfree(bpfsec);
6965 }
6966 #endif
6967
6968 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
6969         .lbs_cred = sizeof(struct task_security_struct),
6970         .lbs_file = sizeof(struct file_security_struct),
6971         .lbs_inode = sizeof(struct inode_security_struct),
6972         .lbs_ipc = sizeof(struct ipc_security_struct),
6973         .lbs_msg_msg = sizeof(struct msg_security_struct),
6974         .lbs_superblock = sizeof(struct superblock_security_struct),
6975         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
6976 };
6977
6978 #ifdef CONFIG_PERF_EVENTS
6979 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6980 {
6981         u32 requested, sid = current_sid();
6982
6983         if (type == PERF_SECURITY_OPEN)
6984                 requested = PERF_EVENT__OPEN;
6985         else if (type == PERF_SECURITY_CPU)
6986                 requested = PERF_EVENT__CPU;
6987         else if (type == PERF_SECURITY_KERNEL)
6988                 requested = PERF_EVENT__KERNEL;
6989         else if (type == PERF_SECURITY_TRACEPOINT)
6990                 requested = PERF_EVENT__TRACEPOINT;
6991         else
6992                 return -EINVAL;
6993
6994         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
6995                             requested, NULL);
6996 }
6997
6998 static int selinux_perf_event_alloc(struct perf_event *event)
6999 {
7000         struct perf_event_security_struct *perfsec;
7001
7002         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7003         if (!perfsec)
7004                 return -ENOMEM;
7005
7006         perfsec->sid = current_sid();
7007         event->security = perfsec;
7008
7009         return 0;
7010 }
7011
7012 static void selinux_perf_event_free(struct perf_event *event)
7013 {
7014         struct perf_event_security_struct *perfsec = event->security;
7015
7016         event->security = NULL;
7017         kfree(perfsec);
7018 }
7019
7020 static int selinux_perf_event_read(struct perf_event *event)
7021 {
7022         struct perf_event_security_struct *perfsec = event->security;
7023         u32 sid = current_sid();
7024
7025         return avc_has_perm(sid, perfsec->sid,
7026                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7027 }
7028
7029 static int selinux_perf_event_write(struct perf_event *event)
7030 {
7031         struct perf_event_security_struct *perfsec = event->security;
7032         u32 sid = current_sid();
7033
7034         return avc_has_perm(sid, perfsec->sid,
7035                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7036 }
7037 #endif
7038
7039 #ifdef CONFIG_IO_URING
7040 /**
7041  * selinux_uring_override_creds - check the requested cred override
7042  * @new: the target creds
7043  *
7044  * Check to see if the current task is allowed to override it's credentials
7045  * to service an io_uring operation.
7046  */
7047 static int selinux_uring_override_creds(const struct cred *new)
7048 {
7049         return avc_has_perm(current_sid(), cred_sid(new),
7050                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7051 }
7052
7053 /**
7054  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7055  *
7056  * Check to see if the current task is allowed to create a new io_uring
7057  * kernel polling thread.
7058  */
7059 static int selinux_uring_sqpoll(void)
7060 {
7061         u32 sid = current_sid();
7062
7063         return avc_has_perm(sid, sid,
7064                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7065 }
7066
7067 /**
7068  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7069  * @ioucmd: the io_uring command structure
7070  *
7071  * Check to see if the current domain is allowed to execute an
7072  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7073  *
7074  */
7075 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7076 {
7077         struct file *file = ioucmd->file;
7078         struct inode *inode = file_inode(file);
7079         struct inode_security_struct *isec = selinux_inode(inode);
7080         struct common_audit_data ad;
7081
7082         ad.type = LSM_AUDIT_DATA_FILE;
7083         ad.u.file = file;
7084
7085         return avc_has_perm(current_sid(), isec->sid,
7086                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7087 }
7088 #endif /* CONFIG_IO_URING */
7089
7090 static const struct lsm_id selinux_lsmid = {
7091         .name = "selinux",
7092         .id = LSM_ID_SELINUX,
7093 };
7094
7095 /*
7096  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7097  * 1. any hooks that don't belong to (2.) or (3.) below,
7098  * 2. hooks that both access structures allocated by other hooks, and allocate
7099  *    structures that can be later accessed by other hooks (mostly "cloning"
7100  *    hooks),
7101  * 3. hooks that only allocate structures that can be later accessed by other
7102  *    hooks ("allocating" hooks).
7103  *
7104  * Please follow block comment delimiters in the list to keep this order.
7105  */
7106 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7107         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7108         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7109         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7110         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7111
7112         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7113         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7114         LSM_HOOK_INIT(capget, selinux_capget),
7115         LSM_HOOK_INIT(capset, selinux_capset),
7116         LSM_HOOK_INIT(capable, selinux_capable),
7117         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7118         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7119         LSM_HOOK_INIT(syslog, selinux_syslog),
7120         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7121
7122         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7123
7124         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7125         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7126         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7127
7128         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7129         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7130         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7131         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7132         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7133         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7134         LSM_HOOK_INIT(sb_mount, selinux_mount),
7135         LSM_HOOK_INIT(sb_umount, selinux_umount),
7136         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7137         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7138
7139         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7140
7141         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7142         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7143
7144         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7145         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7146         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7147         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7148         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7149         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7150         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7151         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7152         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7153         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7154         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7155         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7156         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7157         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7158         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7159         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7160         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7161         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7162         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7163         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7164         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7165         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7166         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7167         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7168         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7169         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7170         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7171         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7172         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7173         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7174         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7175
7176         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7177
7178         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7179         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7180         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7181         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7182         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7183         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7184         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7185         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7186         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7187         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7188         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7189         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7190
7191         LSM_HOOK_INIT(file_open, selinux_file_open),
7192
7193         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7194         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7195         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7196         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7197         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7198         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7199         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7200         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7201         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7202         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7203         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7204         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7205         LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7206         LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7207         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7208         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7209         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7210         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7211         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7212         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7213         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7214         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7215         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7216         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7217         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7218
7219         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7220         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7221
7222         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7223         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7224         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7225         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7226
7227         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7228         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7229         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7230
7231         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7232         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7233         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7234
7235         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7236
7237         LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7238         LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7239         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7240         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7241
7242         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7243         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7244         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7245         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7246         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7247         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7248
7249         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7250         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7251
7252         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7253         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7254         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7255         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7256         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7257         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7258         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7259         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7260         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7261         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7262         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7263         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7264         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7265         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7266         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7267         LSM_HOOK_INIT(socket_getpeersec_stream,
7268                         selinux_socket_getpeersec_stream),
7269         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7270         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7271         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7272         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7273         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7274         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7275         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7276         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7277         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7278         LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7279         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7280         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7281         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7282         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7283         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7284         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7285         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7286         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7287         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7288         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7289         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7290         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7291 #ifdef CONFIG_SECURITY_INFINIBAND
7292         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7293         LSM_HOOK_INIT(ib_endport_manage_subnet,
7294                       selinux_ib_endport_manage_subnet),
7295         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7296 #endif
7297 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7298         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7299         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7300         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7301         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7302         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7303         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7304                         selinux_xfrm_state_pol_flow_match),
7305         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7306 #endif
7307
7308 #ifdef CONFIG_KEYS
7309         LSM_HOOK_INIT(key_free, selinux_key_free),
7310         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7311         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7312 #ifdef CONFIG_KEY_NOTIFICATIONS
7313         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7314 #endif
7315 #endif
7316
7317 #ifdef CONFIG_AUDIT
7318         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7319         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7320         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7321 #endif
7322
7323 #ifdef CONFIG_BPF_SYSCALL
7324         LSM_HOOK_INIT(bpf, selinux_bpf),
7325         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7326         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7327         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7328         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7329 #endif
7330
7331 #ifdef CONFIG_PERF_EVENTS
7332         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7333         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7334         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7335         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7336 #endif
7337
7338 #ifdef CONFIG_IO_URING
7339         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7340         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7341         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7342 #endif
7343
7344         /*
7345          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7346          */
7347         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7348         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7349         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7350         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7351 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7352         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7353 #endif
7354
7355         /*
7356          * PUT "ALLOCATING" HOOKS HERE
7357          */
7358         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7359         LSM_HOOK_INIT(msg_queue_alloc_security,
7360                       selinux_msg_queue_alloc_security),
7361         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7362         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7363         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7364         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7365         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7366         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7367         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7368         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7369 #ifdef CONFIG_SECURITY_INFINIBAND
7370         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7371 #endif
7372 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7373         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7374         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7375         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7376                       selinux_xfrm_state_alloc_acquire),
7377 #endif
7378 #ifdef CONFIG_KEYS
7379         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7380 #endif
7381 #ifdef CONFIG_AUDIT
7382         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7383 #endif
7384 #ifdef CONFIG_BPF_SYSCALL
7385         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7386         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7387 #endif
7388 #ifdef CONFIG_PERF_EVENTS
7389         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7390 #endif
7391 };
7392
7393 static __init int selinux_init(void)
7394 {
7395         pr_info("SELinux:  Initializing.\n");
7396
7397         memset(&selinux_state, 0, sizeof(selinux_state));
7398         enforcing_set(selinux_enforcing_boot);
7399         selinux_avc_init();
7400         mutex_init(&selinux_state.status_lock);
7401         mutex_init(&selinux_state.policy_mutex);
7402
7403         /* Set the security state for the initial task. */
7404         cred_init_security();
7405
7406         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7407         if (!default_noexec)
7408                 pr_notice("SELinux:  virtual memory is executable by default\n");
7409
7410         avc_init();
7411
7412         avtab_cache_init();
7413
7414         ebitmap_cache_init();
7415
7416         hashtab_cache_init();
7417
7418         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7419                            &selinux_lsmid);
7420
7421         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7422                 panic("SELinux: Unable to register AVC netcache callback\n");
7423
7424         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7425                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7426
7427         if (selinux_enforcing_boot)
7428                 pr_debug("SELinux:  Starting in enforcing mode\n");
7429         else
7430                 pr_debug("SELinux:  Starting in permissive mode\n");
7431
7432         fs_validate_description("selinux", selinux_fs_parameters);
7433
7434         return 0;
7435 }
7436
7437 static void delayed_superblock_init(struct super_block *sb, void *unused)
7438 {
7439         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7440 }
7441
7442 void selinux_complete_init(void)
7443 {
7444         pr_debug("SELinux:  Completing initialization.\n");
7445
7446         /* Set up any superblocks initialized prior to the policy load. */
7447         pr_debug("SELinux:  Setting up existing superblocks.\n");
7448         iterate_supers(delayed_superblock_init, NULL);
7449 }
7450
7451 /* SELinux requires early initialization in order to label
7452    all processes and objects when they are created. */
7453 DEFINE_LSM(selinux) = {
7454         .name = "selinux",
7455         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7456         .enabled = &selinux_enabled_boot,
7457         .blobs = &selinux_blob_sizes,
7458         .init = selinux_init,
7459 };
7460
7461 #if defined(CONFIG_NETFILTER)
7462 static const struct nf_hook_ops selinux_nf_ops[] = {
7463         {
7464                 .hook =         selinux_ip_postroute,
7465                 .pf =           NFPROTO_IPV4,
7466                 .hooknum =      NF_INET_POST_ROUTING,
7467                 .priority =     NF_IP_PRI_SELINUX_LAST,
7468         },
7469         {
7470                 .hook =         selinux_ip_forward,
7471                 .pf =           NFPROTO_IPV4,
7472                 .hooknum =      NF_INET_FORWARD,
7473                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7474         },
7475         {
7476                 .hook =         selinux_ip_output,
7477                 .pf =           NFPROTO_IPV4,
7478                 .hooknum =      NF_INET_LOCAL_OUT,
7479                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7480         },
7481 #if IS_ENABLED(CONFIG_IPV6)
7482         {
7483                 .hook =         selinux_ip_postroute,
7484                 .pf =           NFPROTO_IPV6,
7485                 .hooknum =      NF_INET_POST_ROUTING,
7486                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7487         },
7488         {
7489                 .hook =         selinux_ip_forward,
7490                 .pf =           NFPROTO_IPV6,
7491                 .hooknum =      NF_INET_FORWARD,
7492                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7493         },
7494         {
7495                 .hook =         selinux_ip_output,
7496                 .pf =           NFPROTO_IPV6,
7497                 .hooknum =      NF_INET_LOCAL_OUT,
7498                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7499         },
7500 #endif  /* IPV6 */
7501 };
7502
7503 static int __net_init selinux_nf_register(struct net *net)
7504 {
7505         return nf_register_net_hooks(net, selinux_nf_ops,
7506                                      ARRAY_SIZE(selinux_nf_ops));
7507 }
7508
7509 static void __net_exit selinux_nf_unregister(struct net *net)
7510 {
7511         nf_unregister_net_hooks(net, selinux_nf_ops,
7512                                 ARRAY_SIZE(selinux_nf_ops));
7513 }
7514
7515 static struct pernet_operations selinux_net_ops = {
7516         .init = selinux_nf_register,
7517         .exit = selinux_nf_unregister,
7518 };
7519
7520 static int __init selinux_nf_ip_init(void)
7521 {
7522         int err;
7523
7524         if (!selinux_enabled_boot)
7525                 return 0;
7526
7527         pr_debug("SELinux:  Registering netfilter hooks\n");
7528
7529         err = register_pernet_subsys(&selinux_net_ops);
7530         if (err)
7531                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7532
7533         return 0;
7534 }
7535 __initcall(selinux_nf_ip_init);
7536 #endif /* CONFIG_NETFILTER */