fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/addr.h>
  35 #include <linux/sunrpc/stats.h>
  36 #include <linux/sunrpc/metrics.h>
  37 #include <linux/sunrpc/xprtsock.h>
  38 #include <linux/sunrpc/xprtrdma.h>
  39 #include <linux/nfs_fs.h>
  40 #include <linux/nfs_mount.h>
  41 #include <linux/nfs4_mount.h>
  42 #include <linux/lockd/bind.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/namei.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <linux/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "nfs4session.h"
  67 #include "pnfs.h"
  68 #include "nfs.h"
  69
  70 #define NFSDBG_FACILITY         NFSDBG_VFS
  71 #define NFS_TEXT_DATA           1
  72
  73 #if IS_ENABLED(CONFIG_NFS_V3)
  74 #define NFS_DEFAULT_VERSION 3
  75 #else
  76 #define NFS_DEFAULT_VERSION 2
  77 #endif
  78
  79 enum {
  80         /* Mount options that take no arguments */
  81         Opt_soft, Opt_hard,
  82         Opt_posix, Opt_noposix,
  83         Opt_cto, Opt_nocto,
  84         Opt_ac, Opt_noac,
  85         Opt_lock, Opt_nolock,
  86         Opt_udp, Opt_tcp, Opt_rdma,
  87         Opt_acl, Opt_noacl,
  88         Opt_rdirplus, Opt_nordirplus,
  89         Opt_sharecache, Opt_nosharecache,
  90         Opt_resvport, Opt_noresvport,
  91         Opt_fscache, Opt_nofscache,
  92         Opt_migration, Opt_nomigration,
  93
  94         /* Mount options that take integer arguments */
  95         Opt_port,
  96         Opt_rsize, Opt_wsize, Opt_bsize,
  97         Opt_timeo, Opt_retrans,
  98         Opt_acregmin, Opt_acregmax,
  99         Opt_acdirmin, Opt_acdirmax,
 100         Opt_actimeo,
 101         Opt_namelen,
 102         Opt_mountport,
 103         Opt_mountvers,
 104         Opt_minorversion,
 105
 106         /* Mount options that take string arguments */
 107         Opt_nfsvers,
 108         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 109         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 110         Opt_lookupcache,
 111         Opt_fscache_uniq,
 112         Opt_local_lock,
 113
 114         /* Special mount options */
 115         Opt_userspace, Opt_deprecated, Opt_sloppy,
 116
 117         Opt_err
 118 };
 119
 120 static const match_table_t nfs_mount_option_tokens = {
 121         { Opt_userspace, "bg" },
 122         { Opt_userspace, "fg" },
 123         { Opt_userspace, "retry=%s" },
 124
 125         { Opt_sloppy, "sloppy" },
 126
 127         { Opt_soft, "soft" },
 128         { Opt_hard, "hard" },
 129         { Opt_deprecated, "intr" },
 130         { Opt_deprecated, "nointr" },
 131         { Opt_posix, "posix" },
 132         { Opt_noposix, "noposix" },
 133         { Opt_cto, "cto" },
 134         { Opt_nocto, "nocto" },
 135         { Opt_ac, "ac" },
 136         { Opt_noac, "noac" },
 137         { Opt_lock, "lock" },
 138         { Opt_nolock, "nolock" },
 139         { Opt_udp, "udp" },
 140         { Opt_tcp, "tcp" },
 141         { Opt_rdma, "rdma" },
 142         { Opt_acl, "acl" },
 143         { Opt_noacl, "noacl" },
 144         { Opt_rdirplus, "rdirplus" },
 145         { Opt_nordirplus, "nordirplus" },
 146         { Opt_sharecache, "sharecache" },
 147         { Opt_nosharecache, "nosharecache" },
 148         { Opt_resvport, "resvport" },
 149         { Opt_noresvport, "noresvport" },
 150         { Opt_fscache, "fsc" },
 151         { Opt_nofscache, "nofsc" },
 152         { Opt_migration, "migration" },
 153         { Opt_nomigration, "nomigration" },
 154
 155         { Opt_port, "port=%s" },
 156         { Opt_rsize, "rsize=%s" },
 157         { Opt_wsize, "wsize=%s" },
 158         { Opt_bsize, "bsize=%s" },
 159         { Opt_timeo, "timeo=%s" },
 160         { Opt_retrans, "retrans=%s" },
 161         { Opt_acregmin, "acregmin=%s" },
 162         { Opt_acregmax, "acregmax=%s" },
 163         { Opt_acdirmin, "acdirmin=%s" },
 164         { Opt_acdirmax, "acdirmax=%s" },
 165         { Opt_actimeo, "actimeo=%s" },
 166         { Opt_namelen, "namlen=%s" },
 167         { Opt_mountport, "mountport=%s" },
 168         { Opt_mountvers, "mountvers=%s" },
 169         { Opt_minorversion, "minorversion=%s" },
 170
 171         { Opt_nfsvers, "nfsvers=%s" },
 172         { Opt_nfsvers, "vers=%s" },
 173
 174         { Opt_sec, "sec=%s" },
 175         { Opt_proto, "proto=%s" },
 176         { Opt_mountproto, "mountproto=%s" },
 177         { Opt_addr, "addr=%s" },
 178         { Opt_clientaddr, "clientaddr=%s" },
 179         { Opt_mounthost, "mounthost=%s" },
 180         { Opt_mountaddr, "mountaddr=%s" },
 181
 182         { Opt_lookupcache, "lookupcache=%s" },
 183         { Opt_fscache_uniq, "fsc=%s" },
 184         { Opt_local_lock, "local_lock=%s" },
 185
 186         /* The following needs to be listed after all other options */
 187         { Opt_nfsvers, "v%s" },
 188
 189         { Opt_err, NULL }
 190 };
 191
 192 enum {
 193         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 194         Opt_xprt_rdma6,
 195
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205         { Opt_xprt_rdma6, "rdma6" },
 206
 207         { Opt_xprt_err, NULL }
 208 };
 209
 210 enum {
 211         Opt_sec_none, Opt_sec_sys,
 212         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 213         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 214         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 215
 216         Opt_sec_err
 217 };
 218
 219 static const match_table_t nfs_secflavor_tokens = {
 220         { Opt_sec_none, "none" },
 221         { Opt_sec_none, "null" },
 222         { Opt_sec_sys, "sys" },
 223
 224         { Opt_sec_krb5, "krb5" },
 225         { Opt_sec_krb5i, "krb5i" },
 226         { Opt_sec_krb5p, "krb5p" },
 227
 228         { Opt_sec_lkey, "lkey" },
 229         { Opt_sec_lkeyi, "lkeyi" },
 230         { Opt_sec_lkeyp, "lkeyp" },
 231
 232         { Opt_sec_spkm, "spkm3" },
 233         { Opt_sec_spkmi, "spkm3i" },
 234         { Opt_sec_spkmp, "spkm3p" },
 235
 236         { Opt_sec_err, NULL }
 237 };
 238
 239 enum {
 240         Opt_lookupcache_all, Opt_lookupcache_positive,
 241         Opt_lookupcache_none,
 242
 243         Opt_lookupcache_err
 244 };
 245
 246 static match_table_t nfs_lookupcache_tokens = {
 247         { Opt_lookupcache_all, "all" },
 248         { Opt_lookupcache_positive, "pos" },
 249         { Opt_lookupcache_positive, "positive" },
 250         { Opt_lookupcache_none, "none" },
 251
 252         { Opt_lookupcache_err, NULL }
 253 };
 254
 255 enum {
 256         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 257         Opt_local_lock_none,
 258
 259         Opt_local_lock_err
 260 };
 261
 262 static match_table_t nfs_local_lock_tokens = {
 263         { Opt_local_lock_all, "all" },
 264         { Opt_local_lock_flock, "flock" },
 265         { Opt_local_lock_posix, "posix" },
 266         { Opt_local_lock_none, "none" },
 267
 268         { Opt_local_lock_err, NULL }
 269 };
 270
 271 enum {
 272         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 273         Opt_vers_4_1, Opt_vers_4_2,
 274
 275         Opt_vers_err
 276 };
 277
 278 static match_table_t nfs_vers_tokens = {
 279         { Opt_vers_2, "2" },
 280         { Opt_vers_3, "3" },
 281         { Opt_vers_4, "4" },
 282         { Opt_vers_4_0, "4.0" },
 283         { Opt_vers_4_1, "4.1" },
 284         { Opt_vers_4_2, "4.2" },
 285
 286         { Opt_vers_err, NULL }
 287 };
 288
 289 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 290                 int flags, const char *dev_name, void *raw_data);
 291
 292 struct file_system_type nfs_fs_type = {
 293         .owner          = THIS_MODULE,
 294         .name           = "nfs",
 295         .mount          = nfs_fs_mount,
 296         .kill_sb        = nfs_kill_super,
 297         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 298 };
 299 MODULE_ALIAS_FS("nfs");
 300 EXPORT_SYMBOL_GPL(nfs_fs_type);
 301
 302 struct file_system_type nfs_xdev_fs_type = {
 303         .owner          = THIS_MODULE,
 304         .name           = "nfs",
 305         .mount          = nfs_xdev_mount,
 306         .kill_sb        = nfs_kill_super,
 307         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 308 };
 309
 310 const struct super_operations nfs_sops = {
 311         .alloc_inode    = nfs_alloc_inode,
 312         .destroy_inode  = nfs_destroy_inode,
 313         .write_inode    = nfs_write_inode,
 314         .drop_inode     = nfs_drop_inode,
 315         .statfs         = nfs_statfs,
 316         .evict_inode    = nfs_evict_inode,
 317         .umount_begin   = nfs_umount_begin,
 318         .show_options   = nfs_show_options,
 319         .show_devname   = nfs_show_devname,
 320         .show_path      = nfs_show_path,
 321         .show_stats     = nfs_show_stats,
 322         .remount_fs     = nfs_remount,
 323 };
 324 EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326 #if IS_ENABLED(CONFIG_NFS_V4)
 327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328 static int nfs4_validate_mount_data(void *options,
 329         struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331 struct file_system_type nfs4_fs_type = {
 332         .owner          = THIS_MODULE,
 333         .name           = "nfs4",
 334         .mount          = nfs_fs_mount,
 335         .kill_sb        = nfs_kill_super,
 336         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337 };
 338 MODULE_ALIAS_FS("nfs4");
 339 MODULE_ALIAS("nfs4");
 340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342 static int __init register_nfs4_fs(void)
 343 {
 344         return register_filesystem(&nfs4_fs_type);
 345 }
 346
 347 static void unregister_nfs4_fs(void)
 348 {
 349         unregister_filesystem(&nfs4_fs_type);
 350 }
 351 #else
 352 static int __init register_nfs4_fs(void)
 353 {
 354         return 0;
 355 }
 356
 357 static void unregister_nfs4_fs(void)
 358 {
 359 }
 360 #endif
 361
 362 static struct shrinker acl_shrinker = {
 363         .count_objects  = nfs_access_cache_count,
 364         .scan_objects   = nfs_access_cache_scan,
 365         .seeks          = DEFAULT_SEEKS,
 366 };
 367
 368 /*
 369  * Register the NFS filesystems
 370  */
 371 int __init register_nfs_fs(void)
 372 {
 373         int ret;
 374
 375         ret = register_filesystem(&nfs_fs_type);
 376         if (ret < 0)
 377                 goto error_0;
 378
 379         ret = register_nfs4_fs();
 380         if (ret < 0)
 381                 goto error_1;
 382
 383         ret = nfs_register_sysctl();
 384         if (ret < 0)
 385                 goto error_2;
 386         ret = register_shrinker(&acl_shrinker);
 387         if (ret < 0)
 388                 goto error_3;
 389         return 0;
 390 error_3:
 391         nfs_unregister_sysctl();
 392 error_2:
 393         unregister_nfs4_fs();
 394 error_1:
 395         unregister_filesystem(&nfs_fs_type);
 396 error_0:
 397         return ret;
 398 }
 399
 400 /*
 401  * Unregister the NFS filesystems
 402  */
 403 void __exit unregister_nfs_fs(void)
 404 {
 405         unregister_shrinker(&acl_shrinker);
 406         nfs_unregister_sysctl();
 407         unregister_nfs4_fs();
 408         unregister_filesystem(&nfs_fs_type);
 409 }
 410
 411 bool nfs_sb_active(struct super_block *sb)
 412 {
 413         struct nfs_server *server = NFS_SB(sb);
 414
 415         if (!atomic_inc_not_zero(&sb->s_active))
 416                 return false;
 417         if (atomic_inc_return(&server->active) != 1)
 418                 atomic_dec(&sb->s_active);
 419         return true;
 420 }
 421 EXPORT_SYMBOL_GPL(nfs_sb_active);
 422
 423 void nfs_sb_deactive(struct super_block *sb)
 424 {
 425         struct nfs_server *server = NFS_SB(sb);
 426
 427         if (atomic_dec_and_test(&server->active))
 428                 deactivate_super(sb);
 429 }
 430 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 431
 432 /*
 433  * Deliver file system statistics to userspace
 434  */
 435 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 436 {
 437         struct nfs_server *server = NFS_SB(dentry->d_sb);
 438         unsigned char blockbits;
 439         unsigned long blockres;
 440         struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 441         struct nfs_fsstat res;
 442         int error = -ENOMEM;
 443
 444         res.fattr = nfs_alloc_fattr();
 445         if (res.fattr == NULL)
 446                 goto out_err;
 447
 448         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 449         if (unlikely(error == -ESTALE)) {
 450                 struct dentry *pd_dentry;
 451
 452                 pd_dentry = dget_parent(dentry);
 453                 if (pd_dentry != NULL) {
 454                         nfs_zap_caches(d_inode(pd_dentry));
 455                         dput(pd_dentry);
 456                 }
 457         }
 458         nfs_free_fattr(res.fattr);
 459         if (error < 0)
 460                 goto out_err;
 461
 462         buf->f_type = NFS_SUPER_MAGIC;
 463
 464         /*
 465          * Current versions of glibc do not correctly handle the
 466          * case where f_frsize != f_bsize.  Eventually we want to
 467          * report the value of wtmult in this field.
 468          */
 469         buf->f_frsize = dentry->d_sb->s_blocksize;
 470
 471         /*
 472          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 473          * are reported in units of f_frsize.  Linux hasn't had
 474          * an f_frsize field in its statfs struct until recently,
 475          * thus historically Linux's sys_statfs reports these
 476          * fields in units of f_bsize.
 477          */
 478         buf->f_bsize = dentry->d_sb->s_blocksize;
 479         blockbits = dentry->d_sb->s_blocksize_bits;
 480         blockres = (1 << blockbits) - 1;
 481         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 482         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 483         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 484
 485         buf->f_files = res.tfiles;
 486         buf->f_ffree = res.afiles;
 487
 488         buf->f_namelen = server->namelen;
 489
 490         return 0;
 491
 492  out_err:
 493         dprintk("%s: statfs error = %d\n", __func__, -error);
 494         return error;
 495 }
 496 EXPORT_SYMBOL_GPL(nfs_statfs);
 497
 498 /*
 499  * Map the security flavour number to a name
 500  */
 501 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 502 {
 503         static const struct {
 504                 rpc_authflavor_t flavour;
 505                 const char *str;
 506         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 507                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 508                 { RPC_AUTH_NULL, "null" },
 509                 { RPC_AUTH_UNIX, "sys" },
 510                 { RPC_AUTH_GSS_KRB5, "krb5" },
 511                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 512                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 513                 { RPC_AUTH_GSS_LKEY, "lkey" },
 514                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 515                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 516                 { RPC_AUTH_GSS_SPKM, "spkm" },
 517                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 518                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 519                 { UINT_MAX, "unknown" }
 520         };
 521         int i;
 522
 523         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 524                 if (sec_flavours[i].flavour == flavour)
 525                         break;
 526         }
 527         return sec_flavours[i].str;
 528 }
 529
 530 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 531                                   int showdefaults)
 532 {
 533         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 534         char *proto = NULL;
 535
 536         switch (sap->sa_family) {
 537         case AF_INET:
 538                 switch (nfss->mountd_protocol) {
 539                 case IPPROTO_UDP:
 540                         proto = RPCBIND_NETID_UDP;
 541                         break;
 542                 case IPPROTO_TCP:
 543                         proto = RPCBIND_NETID_TCP;
 544                         break;
 545                 }
 546                 break;
 547         case AF_INET6:
 548                 switch (nfss->mountd_protocol) {
 549                 case IPPROTO_UDP:
 550                         proto = RPCBIND_NETID_UDP6;
 551                         break;
 552                 case IPPROTO_TCP:
 553                         proto = RPCBIND_NETID_TCP6;
 554                         break;
 555                 }
 556                 break;
 557         }
 558         if (proto || showdefaults)
 559                 seq_printf(m, ",mountproto=%s", proto ?: "auto");
 560 }
 561
 562 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 563                                     int showdefaults)
 564 {
 565         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 566
 567         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 568                 return;
 569
 570         switch (sap->sa_family) {
 571         case AF_INET: {
 572                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 573                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 574                 break;
 575         }
 576         case AF_INET6: {
 577                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 578                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 579                 break;
 580         }
 581         default:
 582                 if (showdefaults)
 583                         seq_printf(m, ",mountaddr=unspecified");
 584         }
 585
 586         if (nfss->mountd_version || showdefaults)
 587                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 588         if ((nfss->mountd_port &&
 589                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 590                 showdefaults)
 591                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 592
 593         nfs_show_mountd_netid(m, nfss, showdefaults);
 594 }
 595
 596 #if IS_ENABLED(CONFIG_NFS_V4)
 597 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 598                                     int showdefaults)
 599 {
 600         struct nfs_client *clp = nfss->nfs_client;
 601
 602         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 603 }
 604 #else
 605 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 606                                     int showdefaults)
 607 {
 608 }
 609 #endif
 610
 611 static void nfs_show_nfs_version(struct seq_file *m,
 612                 unsigned int version,
 613                 unsigned int minorversion)
 614 {
 615         seq_printf(m, ",vers=%u", version);
 616         if (version == 4)
 617                 seq_printf(m, ".%u", minorversion);
 618 }
 619
 620 /*
 621  * Describe the mount options in force on this server representation
 622  */
 623 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 624                                    int showdefaults)
 625 {
 626         static const struct proc_nfs_info {
 627                 int flag;
 628                 const char *str;
 629                 const char *nostr;
 630         } nfs_info[] = {
 631                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 632                 { NFS_MOUNT_POSIX, ",posix", "" },
 633                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 634                 { NFS_MOUNT_NOAC, ",noac", "" },
 635                 { NFS_MOUNT_NONLM, ",nolock", "" },
 636                 { NFS_MOUNT_NOACL, ",noacl", "" },
 637                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 638                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 639                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 640                 { 0, NULL, NULL }
 641         };
 642         const struct proc_nfs_info *nfs_infop;
 643         struct nfs_client *clp = nfss->nfs_client;
 644         u32 version = clp->rpc_ops->version;
 645         int local_flock, local_fcntl;
 646
 647         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 648         seq_printf(m, ",rsize=%u", nfss->rsize);
 649         seq_printf(m, ",wsize=%u", nfss->wsize);
 650         if (nfss->bsize != 0)
 651                 seq_printf(m, ",bsize=%u", nfss->bsize);
 652         seq_printf(m, ",namlen=%u", nfss->namelen);
 653         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 654                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 655         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 656                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 657         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 658                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 659         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 660                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 661         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 662                 if (nfss->flags & nfs_infop->flag)
 663                         seq_puts(m, nfs_infop->str);
 664                 else
 665                         seq_puts(m, nfs_infop->nostr);
 666         }
 667         rcu_read_lock();
 668         seq_printf(m, ",proto=%s",
 669                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 670         rcu_read_unlock();
 671         if (version == 4) {
 672                 if (nfss->port != NFS_PORT)
 673                         seq_printf(m, ",port=%u", nfss->port);
 674         } else
 675                 if (nfss->port)
 676                         seq_printf(m, ",port=%u", nfss->port);
 677
 678         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 679         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 680         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 681
 682         if (version != 4)
 683                 nfs_show_mountd_options(m, nfss, showdefaults);
 684         else
 685                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 686
 687         if (nfss->options & NFS_OPTION_FSCACHE)
 688                 seq_printf(m, ",fsc");
 689
 690         if (nfss->options & NFS_OPTION_MIGRATION)
 691                 seq_printf(m, ",migration");
 692
 693         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 694                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 695                         seq_printf(m, ",lookupcache=none");
 696                 else
 697                         seq_printf(m, ",lookupcache=pos");
 698         }
 699
 700         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 701         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 702
 703         if (!local_flock && !local_fcntl)
 704                 seq_printf(m, ",local_lock=none");
 705         else if (local_flock && local_fcntl)
 706                 seq_printf(m, ",local_lock=all");
 707         else if (local_flock)
 708                 seq_printf(m, ",local_lock=flock");
 709         else
 710                 seq_printf(m, ",local_lock=posix");
 711 }
 712
 713 /*
 714  * Describe the mount options on this VFS mountpoint
 715  */
 716 int nfs_show_options(struct seq_file *m, struct dentry *root)
 717 {
 718         struct nfs_server *nfss = NFS_SB(root->d_sb);
 719
 720         nfs_show_mount_options(m, nfss, 0);
 721
 722         rcu_read_lock();
 723         seq_printf(m, ",addr=%s",
 724                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 725                                                         RPC_DISPLAY_ADDR));
 726         rcu_read_unlock();
 727
 728         return 0;
 729 }
 730 EXPORT_SYMBOL_GPL(nfs_show_options);
 731
 732 #if IS_ENABLED(CONFIG_NFS_V4)
 733 #ifdef CONFIG_NFS_V4_1
 734 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 735 {
 736         if (nfs4_has_session(server->nfs_client))
 737                 seq_printf(m, ",sessions");
 738 }
 739 #else
 740 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 741 #endif
 742 #endif
 743
 744 #ifdef CONFIG_NFS_V4_1
 745 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 746 {
 747         seq_printf(m, ",pnfs=");
 748         if (server->pnfs_curr_ld)
 749                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 750         else
 751                 seq_printf(m, "not configured");
 752 }
 753
 754 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 755 {
 756         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 757                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 758                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 759                            "date='%llu,%u'",
 760                            impl_id->name, impl_id->domain,
 761                            impl_id->date.seconds, impl_id->date.nseconds);
 762         }
 763 }
 764 #else
 765 #if IS_ENABLED(CONFIG_NFS_V4)
 766 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 767 {
 768 }
 769 #endif
 770 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 771 {
 772 }
 773 #endif
 774
 775 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 776 {
 777         char *page = (char *) __get_free_page(GFP_KERNEL);
 778         char *devname, *dummy;
 779         int err = 0;
 780         if (!page)
 781                 return -ENOMEM;
 782         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 783         if (IS_ERR(devname))
 784                 err = PTR_ERR(devname);
 785         else
 786                 seq_escape(m, devname, " \t\n\\");
 787         free_page((unsigned long)page);
 788         return err;
 789 }
 790 EXPORT_SYMBOL_GPL(nfs_show_devname);
 791
 792 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 793 {
 794         seq_puts(m, "/");
 795         return 0;
 796 }
 797 EXPORT_SYMBOL_GPL(nfs_show_path);
 798
 799 /*
 800  * Present statistical information for this VFS mountpoint
 801  */
 802 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 803 {
 804         int i, cpu;
 805         struct nfs_server *nfss = NFS_SB(root->d_sb);
 806         struct rpc_auth *auth = nfss->client->cl_auth;
 807         struct nfs_iostats totals = { };
 808
 809         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 810
 811         /*
 812          * Display all mount option settings
 813          */
 814         seq_printf(m, "\n\topts:\t");
 815         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 816         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 817         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 818         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 819         nfs_show_mount_options(m, nfss, 1);
 820
 821         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 822
 823         show_implementation_id(m, nfss);
 824
 825         seq_printf(m, "\n\tcaps:\t");
 826         seq_printf(m, "caps=0x%x", nfss->caps);
 827         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 828         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 829         seq_printf(m, ",bsize=%u", nfss->bsize);
 830         seq_printf(m, ",namlen=%u", nfss->namelen);
 831
 832 #if IS_ENABLED(CONFIG_NFS_V4)
 833         if (nfss->nfs_client->rpc_ops->version == 4) {
 834                 seq_printf(m, "\n\tnfsv4:\t");
 835                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 836                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 837                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 838                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 839                 show_sessions(m, nfss);
 840                 show_pnfs(m, nfss);
 841         }
 842 #endif
 843
 844         /*
 845          * Display security flavor in effect for this mount
 846          */
 847         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 848         if (auth->au_flavor)
 849                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 850
 851         /*
 852          * Display superblock I/O counters
 853          */
 854         for_each_possible_cpu(cpu) {
 855                 struct nfs_iostats *stats;
 856
 857                 preempt_disable();
 858                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 859
 860                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 861                         totals.events[i] += stats->events[i];
 862                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 863                         totals.bytes[i] += stats->bytes[i];
 864 #ifdef CONFIG_NFS_FSCACHE
 865                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 866                         totals.fscache[i] += stats->fscache[i];
 867 #endif
 868
 869                 preempt_enable();
 870         }
 871
 872         seq_printf(m, "\n\tevents:\t");
 873         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 874                 seq_printf(m, "%lu ", totals.events[i]);
 875         seq_printf(m, "\n\tbytes:\t");
 876         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 877                 seq_printf(m, "%Lu ", totals.bytes[i]);
 878 #ifdef CONFIG_NFS_FSCACHE
 879         if (nfss->options & NFS_OPTION_FSCACHE) {
 880                 seq_printf(m, "\n\tfsc:\t");
 881                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 882                         seq_printf(m, "%Lu ", totals.fscache[i]);
 883         }
 884 #endif
 885         seq_printf(m, "\n");
 886
 887         rpc_print_iostats(m, nfss->client);
 888
 889         return 0;
 890 }
 891 EXPORT_SYMBOL_GPL(nfs_show_stats);
 892
 893 /*
 894  * Begin unmount by attempting to remove all automounted mountpoints we added
 895  * in response to xdev traversals and referrals
 896  */
 897 void nfs_umount_begin(struct super_block *sb)
 898 {
 899         struct nfs_server *server;
 900         struct rpc_clnt *rpc;
 901
 902         server = NFS_SB(sb);
 903         /* -EIO all pending I/O */
 904         rpc = server->client_acl;
 905         if (!IS_ERR(rpc))
 906                 rpc_killall_tasks(rpc);
 907         rpc = server->client;
 908         if (!IS_ERR(rpc))
 909                 rpc_killall_tasks(rpc);
 910 }
 911 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 912
 913 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 914 {
 915         struct nfs_parsed_mount_data *data;
 916
 917         data = kzalloc(sizeof(*data), GFP_KERNEL);
 918         if (data) {
 919                 data->timeo             = NFS_UNSPEC_TIMEO;
 920                 data->retrans           = NFS_UNSPEC_RETRANS;
 921                 data->acregmin          = NFS_DEF_ACREGMIN;
 922                 data->acregmax          = NFS_DEF_ACREGMAX;
 923                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 924                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 925                 data->mount_server.port = NFS_UNSPEC_PORT;
 926                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 927                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 928                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 929                 data->minorversion      = 0;
 930                 data->need_mount        = true;
 931                 data->net               = current->nsproxy->net_ns;
 932                 security_init_mnt_opts(&data->lsm_opts);
 933         }
 934         return data;
 935 }
 936
 937 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 938 {
 939         if (data) {
 940                 kfree(data->client_address);
 941                 kfree(data->mount_server.hostname);
 942                 kfree(data->nfs_server.export_path);
 943                 kfree(data->nfs_server.hostname);
 944                 kfree(data->fscache_uniq);
 945                 security_free_mnt_opts(&data->lsm_opts);
 946                 kfree(data);
 947         }
 948 }
 949
 950 /*
 951  * Sanity-check a server address provided by the mount command.
 952  *
 953  * Address family must be initialized, and address must not be
 954  * the ANY address for that family.
 955  */
 956 static int nfs_verify_server_address(struct sockaddr *addr)
 957 {
 958         switch (addr->sa_family) {
 959         case AF_INET: {
 960                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 961                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 962         }
 963         case AF_INET6: {
 964                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 965                 return !ipv6_addr_any(sa);
 966         }
 967         }
 968
 969         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 970         return 0;
 971 }
 972
 973 /*
 974  * Select between a default port value and a user-specified port value.
 975  * If a zero value is set, then autobind will be used.
 976  */
 977 static void nfs_set_port(struct sockaddr *sap, int *port,
 978                                  const unsigned short default_port)
 979 {
 980         if (*port == NFS_UNSPEC_PORT)
 981                 *port = default_port;
 982
 983         rpc_set_port(sap, *port);
 984 }
 985
 986 /*
 987  * Sanity check the NFS transport protocol.
 988  *
 989  */
 990 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 991 {
 992         switch (mnt->nfs_server.protocol) {
 993         case XPRT_TRANSPORT_UDP:
 994         case XPRT_TRANSPORT_TCP:
 995         case XPRT_TRANSPORT_RDMA:
 996                 break;
 997         default:
 998                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 999         }
1000 }
1001
1002 /*
1003  * For text based NFSv2/v3 mounts, the mount protocol transport default
1004  * settings should depend upon the specified NFS transport.
1005  */
1006 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1007 {
1008         nfs_validate_transport_protocol(mnt);
1009
1010         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1011             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1012                         return;
1013         switch (mnt->nfs_server.protocol) {
1014         case XPRT_TRANSPORT_UDP:
1015                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1016                 break;
1017         case XPRT_TRANSPORT_TCP:
1018         case XPRT_TRANSPORT_RDMA:
1019                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1020         }
1021 }
1022
1023 /*
1024  * Add 'flavor' to 'auth_info' if not already present.
1025  * Returns true if 'flavor' ends up in the list, false otherwise
1026  */
1027 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1028                               rpc_authflavor_t flavor)
1029 {
1030         unsigned int i;
1031         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1032
1033         /* make sure this flavor isn't already in the list */
1034         for (i = 0; i < auth_info->flavor_len; i++) {
1035                 if (flavor == auth_info->flavors[i])
1036                         return true;
1037         }
1038
1039         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1040                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1041                 return false;
1042         }
1043
1044         auth_info->flavors[auth_info->flavor_len++] = flavor;
1045         return true;
1046 }
1047
1048 /*
1049  * Return true if 'match' is in auth_info or auth_info is empty.
1050  * Return false otherwise.
1051  */
1052 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1053                          rpc_authflavor_t match)
1054 {
1055         int i;
1056
1057         if (!auth_info->flavor_len)
1058                 return true;
1059
1060         for (i = 0; i < auth_info->flavor_len; i++) {
1061                 if (auth_info->flavors[i] == match)
1062                         return true;
1063         }
1064         return false;
1065 }
1066 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1067
1068 /*
1069  * Parse the value of the 'sec=' option.
1070  */
1071 static int nfs_parse_security_flavors(char *value,
1072                                       struct nfs_parsed_mount_data *mnt)
1073 {
1074         substring_t args[MAX_OPT_ARGS];
1075         rpc_authflavor_t pseudoflavor;
1076         char *p;
1077
1078         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1079
1080         while ((p = strsep(&value, ":")) != NULL) {
1081                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1082                 case Opt_sec_none:
1083                         pseudoflavor = RPC_AUTH_NULL;
1084                         break;
1085                 case Opt_sec_sys:
1086                         pseudoflavor = RPC_AUTH_UNIX;
1087                         break;
1088                 case Opt_sec_krb5:
1089                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1090                         break;
1091                 case Opt_sec_krb5i:
1092                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1093                         break;
1094                 case Opt_sec_krb5p:
1095                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1096                         break;
1097                 case Opt_sec_lkey:
1098                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1099                         break;
1100                 case Opt_sec_lkeyi:
1101                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1102                         break;
1103                 case Opt_sec_lkeyp:
1104                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1105                         break;
1106                 case Opt_sec_spkm:
1107                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1108                         break;
1109                 case Opt_sec_spkmi:
1110                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1111                         break;
1112                 case Opt_sec_spkmp:
1113                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1114                         break;
1115                 default:
1116                         dfprintk(MOUNT,
1117                                  "NFS: sec= option '%s' not recognized\n", p);
1118                         return 0;
1119                 }
1120
1121                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1122                         return 0;
1123         }
1124
1125         return 1;
1126 }
1127
1128 static int nfs_parse_version_string(char *string,
1129                 struct nfs_parsed_mount_data *mnt,
1130                 substring_t *args)
1131 {
1132         mnt->flags &= ~NFS_MOUNT_VER3;
1133         switch (match_token(string, nfs_vers_tokens, args)) {
1134         case Opt_vers_2:
1135                 mnt->version = 2;
1136                 break;
1137         case Opt_vers_3:
1138                 mnt->flags |= NFS_MOUNT_VER3;
1139                 mnt->version = 3;
1140                 break;
1141         case Opt_vers_4:
1142                 /* Backward compatibility option. In future,
1143                  * the mount program should always supply
1144                  * a NFSv4 minor version number.
1145                  */
1146                 mnt->version = 4;
1147                 break;
1148         case Opt_vers_4_0:
1149                 mnt->version = 4;
1150                 mnt->minorversion = 0;
1151                 break;
1152         case Opt_vers_4_1:
1153                 mnt->version = 4;
1154                 mnt->minorversion = 1;
1155                 break;
1156         case Opt_vers_4_2:
1157                 mnt->version = 4;
1158                 mnt->minorversion = 2;
1159                 break;
1160         default:
1161                 return 0;
1162         }
1163         return 1;
1164 }
1165
1166 static int nfs_get_option_str(substring_t args[], char **option)
1167 {
1168         kfree(*option);
1169         *option = match_strdup(args);
1170         return !*option;
1171 }
1172
1173 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1174 {
1175         int rc;
1176         char *string;
1177
1178         string = match_strdup(args);
1179         if (string == NULL)
1180                 return -ENOMEM;
1181         rc = kstrtoul(string, 10, option);
1182         kfree(string);
1183
1184         return rc;
1185 }
1186
1187 static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1188                 unsigned long l_bound, unsigned long u_bound)
1189 {
1190         int ret;
1191
1192         ret = nfs_get_option_ul(args, option);
1193         if (ret != 0)
1194                 return ret;
1195         if (*option < l_bound || *option > u_bound)
1196                 return -ERANGE;
1197         return 0;
1198 }
1199
1200 /*
1201  * Error-check and convert a string of mount options from user space into
1202  * a data structure.  The whole mount string is processed; bad options are
1203  * skipped as they are encountered.  If there were no errors, return 1;
1204  * otherwise return 0 (zero).
1205  */
1206 static int nfs_parse_mount_options(char *raw,
1207                                    struct nfs_parsed_mount_data *mnt)
1208 {
1209         char *p, *string, *secdata;
1210         int rc, sloppy = 0, invalid_option = 0;
1211         unsigned short protofamily = AF_UNSPEC;
1212         unsigned short mountfamily = AF_UNSPEC;
1213
1214         if (!raw) {
1215                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1216                 return 1;
1217         }
1218         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1219
1220         secdata = alloc_secdata();
1221         if (!secdata)
1222                 goto out_nomem;
1223
1224         rc = security_sb_copy_data(raw, secdata);
1225         if (rc)
1226                 goto out_security_failure;
1227
1228         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1229         if (rc)
1230                 goto out_security_failure;
1231
1232         free_secdata(secdata);
1233
1234         while ((p = strsep(&raw, ",")) != NULL) {
1235                 substring_t args[MAX_OPT_ARGS];
1236                 unsigned long option;
1237                 int token;
1238
1239                 if (!*p)
1240                         continue;
1241
1242                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1243
1244                 token = match_token(p, nfs_mount_option_tokens, args);
1245                 switch (token) {
1246
1247                 /*
1248                  * boolean options:  foo/nofoo
1249                  */
1250                 case Opt_soft:
1251                         mnt->flags |= NFS_MOUNT_SOFT;
1252                         break;
1253                 case Opt_hard:
1254                         mnt->flags &= ~NFS_MOUNT_SOFT;
1255                         break;
1256                 case Opt_posix:
1257                         mnt->flags |= NFS_MOUNT_POSIX;
1258                         break;
1259                 case Opt_noposix:
1260                         mnt->flags &= ~NFS_MOUNT_POSIX;
1261                         break;
1262                 case Opt_cto:
1263                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1264                         break;
1265                 case Opt_nocto:
1266                         mnt->flags |= NFS_MOUNT_NOCTO;
1267                         break;
1268                 case Opt_ac:
1269                         mnt->flags &= ~NFS_MOUNT_NOAC;
1270                         break;
1271                 case Opt_noac:
1272                         mnt->flags |= NFS_MOUNT_NOAC;
1273                         break;
1274                 case Opt_lock:
1275                         mnt->flags &= ~NFS_MOUNT_NONLM;
1276                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1277                                         NFS_MOUNT_LOCAL_FCNTL);
1278                         break;
1279                 case Opt_nolock:
1280                         mnt->flags |= NFS_MOUNT_NONLM;
1281                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1282                                        NFS_MOUNT_LOCAL_FCNTL);
1283                         break;
1284                 case Opt_udp:
1285                         mnt->flags &= ~NFS_MOUNT_TCP;
1286                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1287                         break;
1288                 case Opt_tcp:
1289                         mnt->flags |= NFS_MOUNT_TCP;
1290                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1291                         break;
1292                 case Opt_rdma:
1293                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1294                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1295                         xprt_load_transport(p);
1296                         break;
1297                 case Opt_acl:
1298                         mnt->flags &= ~NFS_MOUNT_NOACL;
1299                         break;
1300                 case Opt_noacl:
1301                         mnt->flags |= NFS_MOUNT_NOACL;
1302                         break;
1303                 case Opt_rdirplus:
1304                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1305                         break;
1306                 case Opt_nordirplus:
1307                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1308                         break;
1309                 case Opt_sharecache:
1310                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1311                         break;
1312                 case Opt_nosharecache:
1313                         mnt->flags |= NFS_MOUNT_UNSHARED;
1314                         break;
1315                 case Opt_resvport:
1316                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1317                         break;
1318                 case Opt_noresvport:
1319                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1320                         break;
1321                 case Opt_fscache:
1322                         mnt->options |= NFS_OPTION_FSCACHE;
1323                         kfree(mnt->fscache_uniq);
1324                         mnt->fscache_uniq = NULL;
1325                         break;
1326                 case Opt_nofscache:
1327                         mnt->options &= ~NFS_OPTION_FSCACHE;
1328                         kfree(mnt->fscache_uniq);
1329                         mnt->fscache_uniq = NULL;
1330                         break;
1331                 case Opt_migration:
1332                         mnt->options |= NFS_OPTION_MIGRATION;
1333                         break;
1334                 case Opt_nomigration:
1335                         mnt->options &= NFS_OPTION_MIGRATION;
1336                         break;
1337
1338                 /*
1339                  * options that take numeric values
1340                  */
1341                 case Opt_port:
1342                         if (nfs_get_option_ul(args, &option) ||
1343                             option > USHRT_MAX)
1344                                 goto out_invalid_value;
1345                         mnt->nfs_server.port = option;
1346                         break;
1347                 case Opt_rsize:
1348                         if (nfs_get_option_ul(args, &option))
1349                                 goto out_invalid_value;
1350                         mnt->rsize = option;
1351                         break;
1352                 case Opt_wsize:
1353                         if (nfs_get_option_ul(args, &option))
1354                                 goto out_invalid_value;
1355                         mnt->wsize = option;
1356                         break;
1357                 case Opt_bsize:
1358                         if (nfs_get_option_ul(args, &option))
1359                                 goto out_invalid_value;
1360                         mnt->bsize = option;
1361                         break;
1362                 case Opt_timeo:
1363                         if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
1364                                 goto out_invalid_value;
1365                         mnt->timeo = option;
1366                         break;
1367                 case Opt_retrans:
1368                         if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
1369                                 goto out_invalid_value;
1370                         mnt->retrans = option;
1371                         break;
1372                 case Opt_acregmin:
1373                         if (nfs_get_option_ul(args, &option))
1374                                 goto out_invalid_value;
1375                         mnt->acregmin = option;
1376                         break;
1377                 case Opt_acregmax:
1378                         if (nfs_get_option_ul(args, &option))
1379                                 goto out_invalid_value;
1380                         mnt->acregmax = option;
1381                         break;
1382                 case Opt_acdirmin:
1383                         if (nfs_get_option_ul(args, &option))
1384                                 goto out_invalid_value;
1385                         mnt->acdirmin = option;
1386                         break;
1387                 case Opt_acdirmax:
1388                         if (nfs_get_option_ul(args, &option))
1389                                 goto out_invalid_value;
1390                         mnt->acdirmax = option;
1391                         break;
1392                 case Opt_actimeo:
1393                         if (nfs_get_option_ul(args, &option))
1394                                 goto out_invalid_value;
1395                         mnt->acregmin = mnt->acregmax =
1396                         mnt->acdirmin = mnt->acdirmax = option;
1397                         break;
1398                 case Opt_namelen:
1399                         if (nfs_get_option_ul(args, &option))
1400                                 goto out_invalid_value;
1401                         mnt->namlen = option;
1402                         break;
1403                 case Opt_mountport:
1404                         if (nfs_get_option_ul(args, &option) ||
1405                             option > USHRT_MAX)
1406                                 goto out_invalid_value;
1407                         mnt->mount_server.port = option;
1408                         break;
1409                 case Opt_mountvers:
1410                         if (nfs_get_option_ul(args, &option) ||
1411                             option < NFS_MNT_VERSION ||
1412                             option > NFS_MNT3_VERSION)
1413                                 goto out_invalid_value;
1414                         mnt->mount_server.version = option;
1415                         break;
1416                 case Opt_minorversion:
1417                         if (nfs_get_option_ul(args, &option))
1418                                 goto out_invalid_value;
1419                         if (option > NFS4_MAX_MINOR_VERSION)
1420                                 goto out_invalid_value;
1421                         mnt->minorversion = option;
1422                         break;
1423
1424                 /*
1425                  * options that take text values
1426                  */
1427                 case Opt_nfsvers:
1428                         string = match_strdup(args);
1429                         if (string == NULL)
1430                                 goto out_nomem;
1431                         rc = nfs_parse_version_string(string, mnt, args);
1432                         kfree(string);
1433                         if (!rc)
1434                                 goto out_invalid_value;
1435                         break;
1436                 case Opt_sec:
1437                         string = match_strdup(args);
1438                         if (string == NULL)
1439                                 goto out_nomem;
1440                         rc = nfs_parse_security_flavors(string, mnt);
1441                         kfree(string);
1442                         if (!rc) {
1443                                 dfprintk(MOUNT, "NFS:   unrecognized "
1444                                                 "security flavor\n");
1445                                 return 0;
1446                         }
1447                         break;
1448                 case Opt_proto:
1449                         string = match_strdup(args);
1450                         if (string == NULL)
1451                                 goto out_nomem;
1452                         token = match_token(string,
1453                                             nfs_xprt_protocol_tokens, args);
1454
1455                         protofamily = AF_INET;
1456                         switch (token) {
1457                         case Opt_xprt_udp6:
1458                                 protofamily = AF_INET6;
1459                         case Opt_xprt_udp:
1460                                 mnt->flags &= ~NFS_MOUNT_TCP;
1461                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1462                                 break;
1463                         case Opt_xprt_tcp6:
1464                                 protofamily = AF_INET6;
1465                         case Opt_xprt_tcp:
1466                                 mnt->flags |= NFS_MOUNT_TCP;
1467                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1468                                 break;
1469                         case Opt_xprt_rdma6:
1470                                 protofamily = AF_INET6;
1471                         case Opt_xprt_rdma:
1472                                 /* vector side protocols to TCP */
1473                                 mnt->flags |= NFS_MOUNT_TCP;
1474                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1475                                 xprt_load_transport(string);
1476                                 break;
1477                         default:
1478                                 dfprintk(MOUNT, "NFS:   unrecognized "
1479                                                 "transport protocol\n");
1480                                 kfree(string);
1481                                 return 0;
1482                         }
1483                         kfree(string);
1484                         break;
1485                 case Opt_mountproto:
1486                         string = match_strdup(args);
1487                         if (string == NULL)
1488                                 goto out_nomem;
1489                         token = match_token(string,
1490                                             nfs_xprt_protocol_tokens, args);
1491                         kfree(string);
1492
1493                         mountfamily = AF_INET;
1494                         switch (token) {
1495                         case Opt_xprt_udp6:
1496                                 mountfamily = AF_INET6;
1497                         case Opt_xprt_udp:
1498                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1499                                 break;
1500                         case Opt_xprt_tcp6:
1501                                 mountfamily = AF_INET6;
1502                         case Opt_xprt_tcp:
1503                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1504                                 break;
1505                         case Opt_xprt_rdma: /* not used for side protocols */
1506                         default:
1507                                 dfprintk(MOUNT, "NFS:   unrecognized "
1508                                                 "transport protocol\n");
1509                                 return 0;
1510                         }
1511                         break;
1512                 case Opt_addr:
1513                         string = match_strdup(args);
1514                         if (string == NULL)
1515                                 goto out_nomem;
1516                         mnt->nfs_server.addrlen =
1517                                 rpc_pton(mnt->net, string, strlen(string),
1518                                         (struct sockaddr *)
1519                                         &mnt->nfs_server.address,
1520                                         sizeof(mnt->nfs_server.address));
1521                         kfree(string);
1522                         if (mnt->nfs_server.addrlen == 0)
1523                                 goto out_invalid_address;
1524                         break;
1525                 case Opt_clientaddr:
1526                         if (nfs_get_option_str(args, &mnt->client_address))
1527                                 goto out_nomem;
1528                         break;
1529                 case Opt_mounthost:
1530                         if (nfs_get_option_str(args,
1531                                                &mnt->mount_server.hostname))
1532                                 goto out_nomem;
1533                         break;
1534                 case Opt_mountaddr:
1535                         string = match_strdup(args);
1536                         if (string == NULL)
1537                                 goto out_nomem;
1538                         mnt->mount_server.addrlen =
1539                                 rpc_pton(mnt->net, string, strlen(string),
1540                                         (struct sockaddr *)
1541                                         &mnt->mount_server.address,
1542                                         sizeof(mnt->mount_server.address));
1543                         kfree(string);
1544                         if (mnt->mount_server.addrlen == 0)
1545                                 goto out_invalid_address;
1546                         break;
1547                 case Opt_lookupcache:
1548                         string = match_strdup(args);
1549                         if (string == NULL)
1550                                 goto out_nomem;
1551                         token = match_token(string,
1552                                         nfs_lookupcache_tokens, args);
1553                         kfree(string);
1554                         switch (token) {
1555                                 case Opt_lookupcache_all:
1556                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1557                                         break;
1558                                 case Opt_lookupcache_positive:
1559                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1560                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1561                                         break;
1562                                 case Opt_lookupcache_none:
1563                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1564                                         break;
1565                                 default:
1566                                         dfprintk(MOUNT, "NFS:   invalid "
1567                                                         "lookupcache argument\n");
1568                                         return 0;
1569                         };
1570                         break;
1571                 case Opt_fscache_uniq:
1572                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1573                                 goto out_nomem;
1574                         mnt->options |= NFS_OPTION_FSCACHE;
1575                         break;
1576                 case Opt_local_lock:
1577                         string = match_strdup(args);
1578                         if (string == NULL)
1579                                 goto out_nomem;
1580                         token = match_token(string, nfs_local_lock_tokens,
1581                                         args);
1582                         kfree(string);
1583                         switch (token) {
1584                         case Opt_local_lock_all:
1585                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1586                                                NFS_MOUNT_LOCAL_FCNTL);
1587                                 break;
1588                         case Opt_local_lock_flock:
1589                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1590                                 break;
1591                         case Opt_local_lock_posix:
1592                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1593                                 break;
1594                         case Opt_local_lock_none:
1595                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1596                                                 NFS_MOUNT_LOCAL_FCNTL);
1597                                 break;
1598                         default:
1599                                 dfprintk(MOUNT, "NFS:   invalid "
1600                                                 "local_lock argument\n");
1601                                 return 0;
1602                         };
1603                         break;
1604
1605                 /*
1606                  * Special options
1607                  */
1608                 case Opt_sloppy:
1609                         sloppy = 1;
1610                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1611                         break;
1612                 case Opt_userspace:
1613                 case Opt_deprecated:
1614                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1615                                         "'%s'\n", p);
1616                         break;
1617
1618                 default:
1619                         invalid_option = 1;
1620                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1621                                         "'%s'\n", p);
1622                 }
1623         }
1624
1625         if (!sloppy && invalid_option)
1626                 return 0;
1627
1628         if (mnt->minorversion && mnt->version != 4)
1629                 goto out_minorversion_mismatch;
1630
1631         if (mnt->options & NFS_OPTION_MIGRATION &&
1632             (mnt->version != 4 || mnt->minorversion != 0))
1633                 goto out_migration_misuse;
1634
1635         /*
1636          * verify that any proto=/mountproto= options match the address
1637          * families in the addr=/mountaddr= options.
1638          */
1639         if (protofamily != AF_UNSPEC &&
1640             protofamily != mnt->nfs_server.address.ss_family)
1641                 goto out_proto_mismatch;
1642
1643         if (mountfamily != AF_UNSPEC) {
1644                 if (mnt->mount_server.addrlen) {
1645                         if (mountfamily != mnt->mount_server.address.ss_family)
1646                                 goto out_mountproto_mismatch;
1647                 } else {
1648                         if (mountfamily != mnt->nfs_server.address.ss_family)
1649                                 goto out_mountproto_mismatch;
1650                 }
1651         }
1652
1653         return 1;
1654
1655 out_mountproto_mismatch:
1656         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1657                          "option\n");
1658         return 0;
1659 out_proto_mismatch:
1660         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1661         return 0;
1662 out_invalid_address:
1663         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1664         return 0;
1665 out_invalid_value:
1666         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1667         return 0;
1668 out_minorversion_mismatch:
1669         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1670                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1671         return 0;
1672 out_migration_misuse:
1673         printk(KERN_INFO
1674                 "NFS: 'migration' not supported for this NFS version\n");
1675         return 0;
1676 out_nomem:
1677         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1678         return 0;
1679 out_security_failure:
1680         free_secdata(secdata);
1681         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1682         return 0;
1683 }
1684
1685 /*
1686  * Ensure that a specified authtype in args->auth_info is supported by
1687  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1688  * -EACCES if not.
1689  */
1690 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1691                         rpc_authflavor_t *server_authlist, unsigned int count)
1692 {
1693         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1694         unsigned int i;
1695         int use_auth_null = false;
1696
1697         /*
1698          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1699          * must be in the list returned by the server.
1700          *
1701          * AUTH_NULL has a special meaning when it's in the server list - it
1702          * means that the server will ignore the rpc creds, so any flavor
1703          * can be used but still use the sec= that was specified.
1704          */
1705         for (i = 0; i < count; i++) {
1706                 flavor = server_authlist[i];
1707
1708                 if (nfs_auth_info_match(&args->auth_info, flavor))
1709                         goto out;
1710
1711                 if (flavor == RPC_AUTH_NULL)
1712                         use_auth_null = true;
1713         }
1714
1715         if (use_auth_null) {
1716                 flavor = RPC_AUTH_NULL;
1717                 goto out;
1718         }
1719
1720         dfprintk(MOUNT,
1721                  "NFS: specified auth flavors not supported by server\n");
1722         return -EACCES;
1723
1724 out:
1725         args->selected_flavor = flavor;
1726         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1727         return 0;
1728 }
1729
1730 /*
1731  * Use the remote server's MOUNT service to request the NFS file handle
1732  * corresponding to the provided path.
1733  */
1734 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1735                              struct nfs_fh *root_fh,
1736                              rpc_authflavor_t *server_authlist,
1737                              unsigned int *server_authlist_len)
1738 {
1739         struct nfs_mount_request request = {
1740                 .sap            = (struct sockaddr *)
1741                                                 &args->mount_server.address,
1742                 .dirpath        = args->nfs_server.export_path,
1743                 .protocol       = args->mount_server.protocol,
1744                 .fh             = root_fh,
1745                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1746                 .auth_flav_len  = server_authlist_len,
1747                 .auth_flavs     = server_authlist,
1748                 .net            = args->net,
1749         };
1750         int status;
1751
1752         if (args->mount_server.version == 0) {
1753                 switch (args->version) {
1754                         default:
1755                                 args->mount_server.version = NFS_MNT3_VERSION;
1756                                 break;
1757                         case 2:
1758                                 args->mount_server.version = NFS_MNT_VERSION;
1759                 }
1760         }
1761         request.version = args->mount_server.version;
1762
1763         if (args->mount_server.hostname)
1764                 request.hostname = args->mount_server.hostname;
1765         else
1766                 request.hostname = args->nfs_server.hostname;
1767
1768         /*
1769          * Construct the mount server's address.
1770          */
1771         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1772                 memcpy(request.sap, &args->nfs_server.address,
1773                        args->nfs_server.addrlen);
1774                 args->mount_server.addrlen = args->nfs_server.addrlen;
1775         }
1776         request.salen = args->mount_server.addrlen;
1777         nfs_set_port(request.sap, &args->mount_server.port, 0);
1778
1779         /*
1780          * Now ask the mount server to map our export path
1781          * to a file handle.
1782          */
1783         status = nfs_mount(&request);
1784         if (status != 0) {
1785                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1786                                 request.hostname, status);
1787                 return status;
1788         }
1789
1790         return 0;
1791 }
1792
1793 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1794                                         struct nfs_subversion *nfs_mod)
1795 {
1796         int status;
1797         unsigned int i;
1798         bool tried_auth_unix = false;
1799         bool auth_null_in_list = false;
1800         struct nfs_server *server = ERR_PTR(-EACCES);
1801         struct nfs_parsed_mount_data *args = mount_info->parsed;
1802         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1803         unsigned int authlist_len = ARRAY_SIZE(authlist);
1804
1805         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1806                                         &authlist_len);
1807         if (status)
1808                 return ERR_PTR(status);
1809
1810         /*
1811          * Was a sec= authflavor specified in the options? First, verify
1812          * whether the server supports it, and then just try to use it if so.
1813          */
1814         if (args->auth_info.flavor_len > 0) {
1815                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1816                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1817                          args->selected_flavor);
1818                 if (status)
1819                         return ERR_PTR(status);
1820                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1821         }
1822
1823         /*
1824          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1825          * SHOULD prefer the flavor listed first. However, some servers list
1826          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1827          */
1828         for (i = 0; i < authlist_len; ++i) {
1829                 rpc_authflavor_t flavor;
1830                 struct rpcsec_gss_info info;
1831
1832                 flavor = authlist[i];
1833                 switch (flavor) {
1834                 case RPC_AUTH_UNIX:
1835                         tried_auth_unix = true;
1836                         break;
1837                 case RPC_AUTH_NULL:
1838                         auth_null_in_list = true;
1839                         continue;
1840                 default:
1841                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1842                                 continue;
1843                         /* Fallthrough */
1844                 }
1845                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1846                 args->selected_flavor = flavor;
1847                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1848                 if (!IS_ERR(server))
1849                         return server;
1850         }
1851
1852         /*
1853          * Nothing we tried so far worked. At this point, give up if we've
1854          * already tried AUTH_UNIX or if the server's list doesn't contain
1855          * AUTH_NULL
1856          */
1857         if (tried_auth_unix || !auth_null_in_list)
1858                 return server;
1859
1860         /* Last chance! Try AUTH_UNIX */
1861         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1862         args->selected_flavor = RPC_AUTH_UNIX;
1863         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1864 }
1865
1866 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1867                              struct nfs_mount_info *mount_info,
1868                              struct nfs_subversion *nfs_mod)
1869 {
1870         struct nfs_server *server;
1871
1872         if (mount_info->parsed->need_mount)
1873                 server = nfs_try_mount_request(mount_info, nfs_mod);
1874         else
1875                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1876
1877         if (IS_ERR(server))
1878                 return ERR_CAST(server);
1879
1880         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1881 }
1882 EXPORT_SYMBOL_GPL(nfs_try_mount);
1883
1884 /*
1885  * Split "dev_name" into "hostname:export_path".
1886  *
1887  * The leftmost colon demarks the split between the server's hostname
1888  * and the export path.  If the hostname starts with a left square
1889  * bracket, then it may contain colons.
1890  *
1891  * Note: caller frees hostname and export path, even on error.
1892  */
1893 static int nfs_parse_devname(const char *dev_name,
1894                              char **hostname, size_t maxnamlen,
1895                              char **export_path, size_t maxpathlen)
1896 {
1897         size_t len;
1898         char *end;
1899
1900         /* Is the host name protected with square brakcets? */
1901         if (*dev_name == '[') {
1902                 end = strchr(++dev_name, ']');
1903                 if (end == NULL || end[1] != ':')
1904                         goto out_bad_devname;
1905
1906                 len = end - dev_name;
1907                 end++;
1908         } else {
1909                 char *comma;
1910
1911                 end = strchr(dev_name, ':');
1912                 if (end == NULL)
1913                         goto out_bad_devname;
1914                 len = end - dev_name;
1915
1916                 /* kill possible hostname list: not supported */
1917                 comma = strchr(dev_name, ',');
1918                 if (comma != NULL && comma < end)
1919                         *comma = 0;
1920         }
1921
1922         if (len > maxnamlen)
1923                 goto out_hostname;
1924
1925         /* N.B. caller will free nfs_server.hostname in all cases */
1926         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1927         if (*hostname == NULL)
1928                 goto out_nomem;
1929         len = strlen(++end);
1930         if (len > maxpathlen)
1931                 goto out_path;
1932         *export_path = kstrndup(end, len, GFP_KERNEL);
1933         if (!*export_path)
1934                 goto out_nomem;
1935
1936         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1937         return 0;
1938
1939 out_bad_devname:
1940         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1941         return -EINVAL;
1942
1943 out_nomem:
1944         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1945         return -ENOMEM;
1946
1947 out_hostname:
1948         dfprintk(MOUNT, "NFS: server hostname too long\n");
1949         return -ENAMETOOLONG;
1950
1951 out_path:
1952         dfprintk(MOUNT, "NFS: export pathname too long\n");
1953         return -ENAMETOOLONG;
1954 }
1955
1956 /*
1957  * Validate the NFS2/NFS3 mount data
1958  * - fills in the mount root filehandle
1959  *
1960  * For option strings, user space handles the following behaviors:
1961  *
1962  * + DNS: mapping server host name to IP address ("addr=" option)
1963  *
1964  * + failure mode: how to behave if a mount request can't be handled
1965  *   immediately ("fg/bg" option)
1966  *
1967  * + retry: how often to retry a mount request ("retry=" option)
1968  *
1969  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1970  *   mountproto=tcp after mountproto=udp, and so on
1971  */
1972 static int nfs23_validate_mount_data(void *options,
1973                                      struct nfs_parsed_mount_data *args,
1974                                      struct nfs_fh *mntfh,
1975                                      const char *dev_name)
1976 {
1977         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1978         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1979         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1980
1981         if (data == NULL)
1982                 goto out_no_data;
1983
1984         args->version = NFS_DEFAULT_VERSION;
1985         switch (data->version) {
1986         case 1:
1987                 data->namlen = 0;
1988         case 2:
1989                 data->bsize = 0;
1990         case 3:
1991                 if (data->flags & NFS_MOUNT_VER3)
1992                         goto out_no_v3;
1993                 data->root.size = NFS2_FHSIZE;
1994                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1995                 /* Turn off security negotiation */
1996                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1997         case 4:
1998                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1999                         goto out_no_sec;
2000         case 5:
2001                 memset(data->context, 0, sizeof(data->context));
2002         case 6:
2003                 if (data->flags & NFS_MOUNT_VER3) {
2004                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2005                                 goto out_invalid_fh;
2006                         mntfh->size = data->root.size;
2007                         args->version = 3;
2008                 } else {
2009                         mntfh->size = NFS2_FHSIZE;
2010                         args->version = 2;
2011                 }
2012
2013
2014                 memcpy(mntfh->data, data->root.data, mntfh->size);
2015                 if (mntfh->size < sizeof(mntfh->data))
2016                         memset(mntfh->data + mntfh->size, 0,
2017                                sizeof(mntfh->data) - mntfh->size);
2018
2019                 /*
2020                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
2021                  * can deal with.
2022                  */
2023                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2024                 args->flags             |= extra_flags;
2025                 args->rsize             = data->rsize;
2026                 args->wsize             = data->wsize;
2027                 args->timeo             = data->timeo;
2028                 args->retrans           = data->retrans;
2029                 args->acregmin          = data->acregmin;
2030                 args->acregmax          = data->acregmax;
2031                 args->acdirmin          = data->acdirmin;
2032                 args->acdirmax          = data->acdirmax;
2033                 args->need_mount        = false;
2034
2035                 memcpy(sap, &data->addr, sizeof(data->addr));
2036                 args->nfs_server.addrlen = sizeof(data->addr);
2037                 args->nfs_server.port = ntohs(data->addr.sin_port);
2038                 if (!nfs_verify_server_address(sap))
2039                         goto out_no_address;
2040
2041                 if (!(data->flags & NFS_MOUNT_TCP))
2042                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2043                 /* N.B. caller will free nfs_server.hostname in all cases */
2044                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2045                 args->namlen            = data->namlen;
2046                 args->bsize             = data->bsize;
2047
2048                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2049                         args->selected_flavor = data->pseudoflavor;
2050                 else
2051                         args->selected_flavor = RPC_AUTH_UNIX;
2052                 if (!args->nfs_server.hostname)
2053                         goto out_nomem;
2054
2055                 if (!(data->flags & NFS_MOUNT_NONLM))
2056                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2057                                          NFS_MOUNT_LOCAL_FCNTL);
2058                 else
2059                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2060                                         NFS_MOUNT_LOCAL_FCNTL);
2061                 /*
2062                  * The legacy version 6 binary mount data from userspace has a
2063                  * field used only to transport selinux information into the
2064                  * the kernel.  To continue to support that functionality we
2065                  * have a touch of selinux knowledge here in the NFS code. The
2066                  * userspace code converted context=blah to just blah so we are
2067                  * converting back to the full string selinux understands.
2068                  */
2069                 if (data->context[0]){
2070 #ifdef CONFIG_SECURITY_SELINUX
2071                         int rc;
2072                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2073                         if (!opts_str)
2074                                 return -ENOMEM;
2075                         strcpy(opts_str, "context=");
2076                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2077                         strcat(opts_str, &data->context[0]);
2078                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2079                         kfree(opts_str);
2080                         if (rc)
2081                                 return rc;
2082 #else
2083                         return -EINVAL;
2084 #endif
2085                 }
2086
2087                 break;
2088         default:
2089                 return NFS_TEXT_DATA;
2090         }
2091
2092         return 0;
2093
2094 out_no_data:
2095         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2096         return -EINVAL;
2097
2098 out_no_v3:
2099         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2100                  data->version);
2101         return -EINVAL;
2102
2103 out_no_sec:
2104         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2105         return -EINVAL;
2106
2107 out_nomem:
2108         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2109         return -ENOMEM;
2110
2111 out_no_address:
2112         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2113         return -EINVAL;
2114
2115 out_invalid_fh:
2116         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2117         return -EINVAL;
2118 }
2119
2120 #if IS_ENABLED(CONFIG_NFS_V4)
2121 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2122                                    void *options,
2123                                    struct nfs_parsed_mount_data *args,
2124                                    struct nfs_fh *mntfh,
2125                                    const char *dev_name)
2126 {
2127         if (fs_type == &nfs_fs_type)
2128                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2129         return nfs4_validate_mount_data(options, args, dev_name);
2130 }
2131 #else
2132 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2133                                    void *options,
2134                                    struct nfs_parsed_mount_data *args,
2135                                    struct nfs_fh *mntfh,
2136                                    const char *dev_name)
2137 {
2138         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2139 }
2140 #endif
2141
2142 static int nfs_validate_text_mount_data(void *options,
2143                                         struct nfs_parsed_mount_data *args,
2144                                         const char *dev_name)
2145 {
2146         int port = 0;
2147         int max_namelen = PAGE_SIZE;
2148         int max_pathlen = NFS_MAXPATHLEN;
2149         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2150
2151         if (nfs_parse_mount_options((char *)options, args) == 0)
2152                 return -EINVAL;
2153
2154         if (!nfs_verify_server_address(sap))
2155                 goto out_no_address;
2156
2157         if (args->version == 4) {
2158 #if IS_ENABLED(CONFIG_NFS_V4)
2159                 port = NFS_PORT;
2160                 max_namelen = NFS4_MAXNAMLEN;
2161                 max_pathlen = NFS4_MAXPATHLEN;
2162                 nfs_validate_transport_protocol(args);
2163                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2164                         goto out_invalid_transport_udp;
2165                 nfs4_validate_mount_flags(args);
2166 #else
2167                 goto out_v4_not_compiled;
2168 #endif /* CONFIG_NFS_V4 */
2169         } else
2170                 nfs_set_mount_transport_protocol(args);
2171
2172         nfs_set_port(sap, &args->nfs_server.port, port);
2173
2174         return nfs_parse_devname(dev_name,
2175                                    &args->nfs_server.hostname,
2176                                    max_namelen,
2177                                    &args->nfs_server.export_path,
2178                                    max_pathlen);
2179
2180 #if !IS_ENABLED(CONFIG_NFS_V4)
2181 out_v4_not_compiled:
2182         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2183         return -EPROTONOSUPPORT;
2184 #else
2185 out_invalid_transport_udp:
2186         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2187         return -EINVAL;
2188 #endif /* !CONFIG_NFS_V4 */
2189
2190 out_no_address:
2191         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2192         return -EINVAL;
2193 }
2194
2195 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2196                 | NFS_MOUNT_SECURE \
2197                 | NFS_MOUNT_TCP \
2198                 | NFS_MOUNT_VER3 \
2199                 | NFS_MOUNT_KERBEROS \
2200                 | NFS_MOUNT_NONLM \
2201                 | NFS_MOUNT_BROKEN_SUID \
2202                 | NFS_MOUNT_STRICTLOCK \
2203                 | NFS_MOUNT_LEGACY_INTERFACE)
2204
2205 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2206                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2207
2208 static int
2209 nfs_compare_remount_data(struct nfs_server *nfss,
2210                          struct nfs_parsed_mount_data *data)
2211 {
2212         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2213             data->rsize != nfss->rsize ||
2214             data->wsize != nfss->wsize ||
2215             data->version != nfss->nfs_client->rpc_ops->version ||
2216             data->minorversion != nfss->nfs_client->cl_minorversion ||
2217             data->retrans != nfss->client->cl_timeout->to_retries ||
2218             !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2219             data->acregmin != nfss->acregmin / HZ ||
2220             data->acregmax != nfss->acregmax / HZ ||
2221             data->acdirmin != nfss->acdirmin / HZ ||
2222             data->acdirmax != nfss->acdirmax / HZ ||
2223             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2224             data->nfs_server.port != nfss->port ||
2225             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2226             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2227                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2228                 return -EINVAL;
2229
2230         return 0;
2231 }
2232
2233 int
2234 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2235 {
2236         int error;
2237         struct nfs_server *nfss = sb->s_fs_info;
2238         struct nfs_parsed_mount_data *data;
2239         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2240         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2241         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2242
2243         sync_filesystem(sb);
2244
2245         /*
2246          * Userspace mount programs that send binary options generally send
2247          * them populated with default values. We have no way to know which
2248          * ones were explicitly specified. Fall back to legacy behavior and
2249          * just return success.
2250          */
2251         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2252             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2253                                            options->version <= 6))))
2254                 return 0;
2255
2256         data = kzalloc(sizeof(*data), GFP_KERNEL);
2257         if (data == NULL)
2258                 return -ENOMEM;
2259
2260         /* fill out struct with values from existing mount */
2261         data->flags = nfss->flags;
2262         data->rsize = nfss->rsize;
2263         data->wsize = nfss->wsize;
2264         data->retrans = nfss->client->cl_timeout->to_retries;
2265         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2266         data->acregmin = nfss->acregmin / HZ;
2267         data->acregmax = nfss->acregmax / HZ;
2268         data->acdirmin = nfss->acdirmin / HZ;
2269         data->acdirmax = nfss->acdirmax / HZ;
2270         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2271         data->nfs_server.port = nfss->port;
2272         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2273         data->version = nfsvers;
2274         data->minorversion = nfss->nfs_client->cl_minorversion;
2275         data->net = current->nsproxy->net_ns;
2276         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2277                 data->nfs_server.addrlen);
2278
2279         /* overwrite those values with any that were specified */
2280         error = -EINVAL;
2281         if (!nfs_parse_mount_options((char *)options, data))
2282                 goto out;
2283
2284         /*
2285          * noac is a special case. It implies -o sync, but that's not
2286          * necessarily reflected in the mtab options. do_remount_sb
2287          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2288          * remount options, so we have to explicitly reset it.
2289          */
2290         if (data->flags & NFS_MOUNT_NOAC)
2291                 *flags |= MS_SYNCHRONOUS;
2292
2293         /* compare new mount options with old ones */
2294         error = nfs_compare_remount_data(nfss, data);
2295 out:
2296         kfree(data);
2297         return error;
2298 }
2299 EXPORT_SYMBOL_GPL(nfs_remount);
2300
2301 /*
2302  * Initialise the common bits of the superblock
2303  */
2304 static void nfs_initialise_sb(struct super_block *sb)
2305 {
2306         struct nfs_server *server = NFS_SB(sb);
2307
2308         sb->s_magic = NFS_SUPER_MAGIC;
2309
2310         /* We probably want something more informative here */
2311         snprintf(sb->s_id, sizeof(sb->s_id),
2312                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2313
2314         if (sb->s_blocksize == 0)
2315                 sb->s_blocksize = nfs_block_bits(server->wsize,
2316                                                  &sb->s_blocksize_bits);
2317
2318         nfs_super_set_maxbytes(sb, server->maxfilesize);
2319 }
2320
2321 /*
2322  * Finish setting up an NFS2/3 superblock
2323  */
2324 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2325 {
2326         struct nfs_parsed_mount_data *data = mount_info->parsed;
2327         struct nfs_server *server = NFS_SB(sb);
2328
2329         sb->s_blocksize_bits = 0;
2330         sb->s_blocksize = 0;
2331         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2332         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2333         if (data && data->bsize)
2334                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2335
2336         if (server->nfs_client->rpc_ops->version != 2) {
2337                 /* The VFS shouldn't apply the umask to mode bits. We will do
2338                  * so ourselves when necessary.
2339                  */
2340                 sb->s_flags |= MS_POSIXACL;
2341                 sb->s_time_gran = 1;
2342                 sb->s_export_op = &nfs_export_ops;
2343         }
2344
2345         nfs_initialise_sb(sb);
2346 }
2347 EXPORT_SYMBOL_GPL(nfs_fill_super);
2348
2349 /*
2350  * Finish setting up a cloned NFS2/3/4 superblock
2351  */
2352 static void nfs_clone_super(struct super_block *sb,
2353                             struct nfs_mount_info *mount_info)
2354 {
2355         const struct super_block *old_sb = mount_info->cloned->sb;
2356         struct nfs_server *server = NFS_SB(sb);
2357
2358         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2359         sb->s_blocksize = old_sb->s_blocksize;
2360         sb->s_maxbytes = old_sb->s_maxbytes;
2361         sb->s_xattr = old_sb->s_xattr;
2362         sb->s_op = old_sb->s_op;
2363         sb->s_time_gran = 1;
2364         sb->s_export_op = old_sb->s_export_op;
2365
2366         if (server->nfs_client->rpc_ops->version != 2) {
2367                 /* The VFS shouldn't apply the umask to mode bits. We will do
2368                  * so ourselves when necessary.
2369                  */
2370                 sb->s_flags |= MS_POSIXACL;
2371         }
2372
2373         nfs_initialise_sb(sb);
2374 }
2375
2376 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2377 {
2378         const struct nfs_server *a = s->s_fs_info;
2379         const struct rpc_clnt *clnt_a = a->client;
2380         const struct rpc_clnt *clnt_b = b->client;
2381
2382         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2383                 goto Ebusy;
2384         if (a->nfs_client != b->nfs_client)
2385                 goto Ebusy;
2386         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2387                 goto Ebusy;
2388         if (a->wsize != b->wsize)
2389                 goto Ebusy;
2390         if (a->rsize != b->rsize)
2391                 goto Ebusy;
2392         if (a->acregmin != b->acregmin)
2393                 goto Ebusy;
2394         if (a->acregmax != b->acregmax)
2395                 goto Ebusy;
2396         if (a->acdirmin != b->acdirmin)
2397                 goto Ebusy;
2398         if (a->acdirmax != b->acdirmax)
2399                 goto Ebusy;
2400         if (b->auth_info.flavor_len > 0 &&
2401            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2402                 goto Ebusy;
2403         return 1;
2404 Ebusy:
2405         return 0;
2406 }
2407
2408 struct nfs_sb_mountdata {
2409         struct nfs_server *server;
2410         int mntflags;
2411 };
2412
2413 static int nfs_set_super(struct super_block *s, void *data)
2414 {
2415         struct nfs_sb_mountdata *sb_mntdata = data;
2416         struct nfs_server *server = sb_mntdata->server;
2417         int ret;
2418
2419         s->s_flags = sb_mntdata->mntflags;
2420         s->s_fs_info = server;
2421         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2422         ret = set_anon_super(s, server);
2423         if (ret == 0)
2424                 server->s_dev = s->s_dev;
2425         return ret;
2426 }
2427
2428 static int nfs_compare_super_address(struct nfs_server *server1,
2429                                      struct nfs_server *server2)
2430 {
2431         struct sockaddr *sap1, *sap2;
2432         struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2433         struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2434
2435         if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2436                 return 0;
2437
2438         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2439         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2440
2441         if (sap1->sa_family != sap2->sa_family)
2442                 return 0;
2443
2444         switch (sap1->sa_family) {
2445         case AF_INET: {
2446                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2447                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2448                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2449                         return 0;
2450                 if (sin1->sin_port != sin2->sin_port)
2451                         return 0;
2452                 break;
2453         }
2454         case AF_INET6: {
2455                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2456                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2457                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2458                         return 0;
2459                 if (sin1->sin6_port != sin2->sin6_port)
2460                         return 0;
2461                 break;
2462         }
2463         default:
2464                 return 0;
2465         }
2466
2467         return 1;
2468 }
2469
2470 static int nfs_compare_super(struct super_block *sb, void *data)
2471 {
2472         struct nfs_sb_mountdata *sb_mntdata = data;
2473         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2474         int mntflags = sb_mntdata->mntflags;
2475
2476         if (!nfs_compare_super_address(old, server))
2477                 return 0;
2478         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2479         if (old->flags & NFS_MOUNT_UNSHARED)
2480                 return 0;
2481         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2482                 return 0;
2483         return nfs_compare_mount_options(sb, server, mntflags);
2484 }
2485
2486 #ifdef CONFIG_NFS_FSCACHE
2487 static void nfs_get_cache_cookie(struct super_block *sb,
2488                                  struct nfs_parsed_mount_data *parsed,
2489                                  struct nfs_clone_mount *cloned)
2490 {
2491         struct nfs_server *nfss = NFS_SB(sb);
2492         char *uniq = NULL;
2493         int ulen = 0;
2494
2495         nfss->fscache_key = NULL;
2496         nfss->fscache = NULL;
2497
2498         if (parsed) {
2499                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2500                         return;
2501                 if (parsed->fscache_uniq) {
2502                         uniq = parsed->fscache_uniq;
2503                         ulen = strlen(parsed->fscache_uniq);
2504                 }
2505         } else if (cloned) {
2506                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2507                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2508                         return;
2509                 if (mnt_s->fscache_key) {
2510                         uniq = mnt_s->fscache_key->key.uniquifier;
2511                         ulen = mnt_s->fscache_key->key.uniq_len;
2512                 };
2513         } else
2514                 return;
2515
2516         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2517 }
2518 #else
2519 static void nfs_get_cache_cookie(struct super_block *sb,
2520                                  struct nfs_parsed_mount_data *parsed,
2521                                  struct nfs_clone_mount *cloned)
2522 {
2523 }
2524 #endif
2525
2526 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2527                         struct nfs_mount_info *mount_info)
2528 {
2529         int error;
2530         unsigned long kflags = 0, kflags_out = 0;
2531         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2532                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2533
2534         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2535                                                 kflags, &kflags_out);
2536         if (error)
2537                 goto err;
2538
2539         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2540                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2541                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2542 err:
2543         return error;
2544 }
2545 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2546
2547 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2548                           struct nfs_mount_info *mount_info)
2549 {
2550         int error;
2551         unsigned long kflags = 0, kflags_out = 0;
2552
2553         /* clone any lsm security options from the parent to the new sb */
2554         if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2555                 return -ESTALE;
2556
2557         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2558                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2559
2560         error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
2561                         &kflags_out);
2562         if (error)
2563                 return error;
2564
2565         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2566                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2567                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2568         return 0;
2569 }
2570 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2571
2572 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2573                                    int flags, const char *dev_name,
2574                                    struct nfs_mount_info *mount_info,
2575                                    struct nfs_subversion *nfs_mod)
2576 {
2577         struct super_block *s;
2578         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2579         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2580         struct nfs_sb_mountdata sb_mntdata = {
2581                 .mntflags = flags,
2582                 .server = server,
2583         };
2584         int error;
2585
2586         if (server->flags & NFS_MOUNT_UNSHARED)
2587                 compare_super = NULL;
2588
2589         /* -o noac implies -o sync */
2590         if (server->flags & NFS_MOUNT_NOAC)
2591                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2592
2593         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2594                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2595                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2596
2597         /* Get a superblock - note that we may end up sharing one that already exists */
2598         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2599         if (IS_ERR(s)) {
2600                 mntroot = ERR_CAST(s);
2601                 goto out_err_nosb;
2602         }
2603
2604         if (s->s_fs_info != server) {
2605                 nfs_free_server(server);
2606                 server = NULL;
2607         } else {
2608                 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
2609                                              MINOR(server->s_dev));
2610                 if (error) {
2611                         mntroot = ERR_PTR(error);
2612                         goto error_splat_super;
2613                 }
2614                 s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
2615                 server->super = s;
2616         }
2617
2618         if (!s->s_root) {
2619                 /* initial superblock/root creation */
2620                 mount_info->fill_super(s, mount_info);
2621                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2622         }
2623
2624         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2625         if (IS_ERR(mntroot))
2626                 goto error_splat_super;
2627
2628         error = mount_info->set_security(s, mntroot, mount_info);
2629         if (error)
2630                 goto error_splat_root;
2631
2632         s->s_flags |= MS_ACTIVE;
2633
2634 out:
2635         return mntroot;
2636
2637 out_err_nosb:
2638         nfs_free_server(server);
2639         goto out;
2640
2641 error_splat_root:
2642         dput(mntroot);
2643         mntroot = ERR_PTR(error);
2644 error_splat_super:
2645         deactivate_locked_super(s);
2646         goto out;
2647 }
2648 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2649
2650 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2651         int flags, const char *dev_name, void *raw_data)
2652 {
2653         struct nfs_mount_info mount_info = {
2654                 .fill_super = nfs_fill_super,
2655                 .set_security = nfs_set_sb_security,
2656         };
2657         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2658         struct nfs_subversion *nfs_mod;
2659         int error;
2660
2661         mount_info.parsed = nfs_alloc_parsed_mount_data();
2662         mount_info.mntfh = nfs_alloc_fhandle();
2663         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2664                 goto out;
2665
2666         /* Validate the mount data */
2667         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2668         if (error == NFS_TEXT_DATA)
2669                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2670         if (error < 0) {
2671                 mntroot = ERR_PTR(error);
2672                 goto out;
2673         }
2674
2675         nfs_mod = get_nfs_version(mount_info.parsed->version);
2676         if (IS_ERR(nfs_mod)) {
2677                 mntroot = ERR_CAST(nfs_mod);
2678                 goto out;
2679         }
2680
2681         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2682
2683         put_nfs_version(nfs_mod);
2684 out:
2685         nfs_free_parsed_mount_data(mount_info.parsed);
2686         nfs_free_fhandle(mount_info.mntfh);
2687         return mntroot;
2688 }
2689 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2690
2691 /*
2692  * Destroy an NFS2/3 superblock
2693  */
2694 void nfs_kill_super(struct super_block *s)
2695 {
2696         struct nfs_server *server = NFS_SB(s);
2697         dev_t dev = s->s_dev;
2698
2699         generic_shutdown_super(s);
2700
2701         nfs_fscache_release_super_cookie(s);
2702
2703         nfs_free_server(server);
2704         free_anon_bdev(dev);
2705 }
2706 EXPORT_SYMBOL_GPL(nfs_kill_super);
2707
2708 /*
2709  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2710  */
2711 static struct dentry *
2712 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2713                 const char *dev_name, void *raw_data)
2714 {
2715         struct nfs_clone_mount *data = raw_data;
2716         struct nfs_mount_info mount_info = {
2717                 .fill_super = nfs_clone_super,
2718                 .set_security = nfs_clone_sb_security,
2719                 .cloned = data,
2720         };
2721         struct nfs_server *server;
2722         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2723         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2724
2725         dprintk("--> nfs_xdev_mount()\n");
2726
2727         mount_info.mntfh = mount_info.cloned->fh;
2728
2729         /* create a new volume representation */
2730         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2731
2732         if (IS_ERR(server))
2733                 mntroot = ERR_CAST(server);
2734         else
2735                 mntroot = nfs_fs_mount_common(server, flags,
2736                                 dev_name, &mount_info, nfs_mod);
2737
2738         dprintk("<-- nfs_xdev_mount() = %ld\n",
2739                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2740         return mntroot;
2741 }
2742
2743 #if IS_ENABLED(CONFIG_NFS_V4)
2744
2745 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2746 {
2747         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2748                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2749 }
2750
2751 /*
2752  * Validate NFSv4 mount options
2753  */
2754 static int nfs4_validate_mount_data(void *options,
2755                                     struct nfs_parsed_mount_data *args,
2756                                     const char *dev_name)
2757 {
2758         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2759         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2760         char *c;
2761
2762         if (data == NULL)
2763                 goto out_no_data;
2764
2765         args->version = 4;
2766
2767         switch (data->version) {
2768         case 1:
2769                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2770                         goto out_no_address;
2771                 if (data->host_addrlen == 0)
2772                         goto out_no_address;
2773                 args->nfs_server.addrlen = data->host_addrlen;
2774                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2775                         return -EFAULT;
2776                 if (!nfs_verify_server_address(sap))
2777                         goto out_no_address;
2778                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2779
2780                 if (data->auth_flavourlen) {
2781                         rpc_authflavor_t pseudoflavor;
2782                         if (data->auth_flavourlen > 1)
2783                                 goto out_inval_auth;
2784                         if (copy_from_user(&pseudoflavor,
2785                                            data->auth_flavours,
2786                                            sizeof(pseudoflavor)))
2787                                 return -EFAULT;
2788                         args->selected_flavor = pseudoflavor;
2789                 } else
2790                         args->selected_flavor = RPC_AUTH_UNIX;
2791
2792                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2793                 if (IS_ERR(c))
2794                         return PTR_ERR(c);
2795                 args->nfs_server.hostname = c;
2796
2797                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2798                 if (IS_ERR(c))
2799                         return PTR_ERR(c);
2800                 args->nfs_server.export_path = c;
2801                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2802
2803                 c = strndup_user(data->client_addr.data, 16);
2804                 if (IS_ERR(c))
2805                         return PTR_ERR(c);
2806                 args->client_address = c;
2807
2808                 /*
2809                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2810                  * can deal with.
2811                  */
2812
2813                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2814                 args->rsize     = data->rsize;
2815                 args->wsize     = data->wsize;
2816                 args->timeo     = data->timeo;
2817                 args->retrans   = data->retrans;
2818                 args->acregmin  = data->acregmin;
2819                 args->acregmax  = data->acregmax;
2820                 args->acdirmin  = data->acdirmin;
2821                 args->acdirmax  = data->acdirmax;
2822                 args->nfs_server.protocol = data->proto;
2823                 nfs_validate_transport_protocol(args);
2824                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2825                         goto out_invalid_transport_udp;
2826
2827                 break;
2828         default:
2829                 return NFS_TEXT_DATA;
2830         }
2831
2832         return 0;
2833
2834 out_no_data:
2835         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2836         return -EINVAL;
2837
2838 out_inval_auth:
2839         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2840                  data->auth_flavourlen);
2841         return -EINVAL;
2842
2843 out_no_address:
2844         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2845         return -EINVAL;
2846
2847 out_invalid_transport_udp:
2848         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2849         return -EINVAL;
2850 }
2851
2852 /*
2853  * NFS v4 module parameters need to stay in the
2854  * NFS client for backwards compatibility
2855  */
2856 unsigned int nfs_callback_set_tcpport;
2857 unsigned short nfs_callback_nr_threads;
2858 /* Default cache timeout is 10 minutes */
2859 unsigned int nfs_idmap_cache_timeout = 600;
2860 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2861 bool nfs4_disable_idmapping = true;
2862 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2863 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
2864 unsigned short send_implementation_id = 1;
2865 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2866 bool recover_lost_locks = false;
2867
2868 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
2869 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2870 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2871 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2872 EXPORT_SYMBOL_GPL(max_session_slots);
2873 EXPORT_SYMBOL_GPL(max_session_cb_slots);
2874 EXPORT_SYMBOL_GPL(send_implementation_id);
2875 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2876 EXPORT_SYMBOL_GPL(recover_lost_locks);
2877
2878 #define NFS_CALLBACK_MAXPORTNR (65535U)
2879
2880 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2881 {
2882         unsigned long num;
2883         int ret;
2884
2885         if (!val)
2886                 return -EINVAL;
2887         ret = kstrtoul(val, 0, &num);
2888         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2889                 return -EINVAL;
2890         *((unsigned int *)kp->arg) = num;
2891         return 0;
2892 }
2893 static const struct kernel_param_ops param_ops_portnr = {
2894         .set = param_set_portnr,
2895         .get = param_get_uint,
2896 };
2897 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2898
2899 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2900 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
2901 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
2902                 "assigned to the NFSv4 callback channels.");
2903 module_param(nfs_idmap_cache_timeout, int, 0644);
2904 module_param(nfs4_disable_idmapping, bool, 0644);
2905 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2906                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2907 MODULE_PARM_DESC(nfs4_disable_idmapping,
2908                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2909 module_param(max_session_slots, ushort, 0644);
2910 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2911                 "requests the client will negotiate");
2912 module_param(max_session_cb_slots, ushort, 0644);
2913 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
2914                 "callbacks the client will process for a given server");
2915 module_param(send_implementation_id, ushort, 0644);
2916 MODULE_PARM_DESC(send_implementation_id,
2917                 "Send implementation ID with NFSv4.1 exchange_id");
2918 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2919
2920 module_param(recover_lost_locks, bool, 0644);
2921 MODULE_PARM_DESC(recover_lost_locks,
2922                  "If the server reports that a lock might be lost, "
2923                  "try to recover it risking data corruption.");
2924
2925
2926 #endif /* CONFIG_NFS_V4 */