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