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/nfs_idmap.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56 #include <linux/nsproxy.h>
  57 #include <linux/rcupdate.h>
  58
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67 #include "nfs4session.h"
  68 #include "pnfs.h"
  69 #include "nfs.h"
  70
  71 #define NFSDBG_FACILITY         NFSDBG_VFS
  72 #define NFS_TEXT_DATA           1
  73
  74 #if IS_ENABLED(CONFIG_NFS_V3)
  75 #define NFS_DEFAULT_VERSION 3
  76 #else
  77 #define NFS_DEFAULT_VERSION 2
  78 #endif
  79
  80 enum {
  81         /* Mount options that take no arguments */
  82         Opt_soft, Opt_hard,
  83         Opt_posix, Opt_noposix,
  84         Opt_cto, Opt_nocto,
  85         Opt_ac, Opt_noac,
  86         Opt_lock, Opt_nolock,
  87         Opt_udp, Opt_tcp, Opt_rdma,
  88         Opt_acl, Opt_noacl,
  89         Opt_rdirplus, Opt_nordirplus,
  90         Opt_sharecache, Opt_nosharecache,
  91         Opt_resvport, Opt_noresvport,
  92         Opt_fscache, Opt_nofscache,
  93         Opt_migration, Opt_nomigration,
  94
  95         /* Mount options that take integer arguments */
  96         Opt_port,
  97         Opt_rsize, Opt_wsize, Opt_bsize,
  98         Opt_timeo, Opt_retrans,
  99         Opt_acregmin, Opt_acregmax,
 100         Opt_acdirmin, Opt_acdirmax,
 101         Opt_actimeo,
 102         Opt_namelen,
 103         Opt_mountport,
 104         Opt_mountvers,
 105         Opt_minorversion,
 106
 107         /* Mount options that take string arguments */
 108         Opt_nfsvers,
 109         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 110         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 111         Opt_lookupcache,
 112         Opt_fscache_uniq,
 113         Opt_local_lock,
 114
 115         /* Special mount options */
 116         Opt_userspace, Opt_deprecated, Opt_sloppy,
 117
 118         Opt_err
 119 };
 120
 121 static const match_table_t nfs_mount_option_tokens = {
 122         { Opt_userspace, "bg" },
 123         { Opt_userspace, "fg" },
 124         { Opt_userspace, "retry=%s" },
 125
 126         { Opt_sloppy, "sloppy" },
 127
 128         { Opt_soft, "soft" },
 129         { Opt_hard, "hard" },
 130         { Opt_deprecated, "intr" },
 131         { Opt_deprecated, "nointr" },
 132         { Opt_posix, "posix" },
 133         { Opt_noposix, "noposix" },
 134         { Opt_cto, "cto" },
 135         { Opt_nocto, "nocto" },
 136         { Opt_ac, "ac" },
 137         { Opt_noac, "noac" },
 138         { Opt_lock, "lock" },
 139         { Opt_nolock, "nolock" },
 140         { Opt_udp, "udp" },
 141         { Opt_tcp, "tcp" },
 142         { Opt_rdma, "rdma" },
 143         { Opt_acl, "acl" },
 144         { Opt_noacl, "noacl" },
 145         { Opt_rdirplus, "rdirplus" },
 146         { Opt_nordirplus, "nordirplus" },
 147         { Opt_sharecache, "sharecache" },
 148         { Opt_nosharecache, "nosharecache" },
 149         { Opt_resvport, "resvport" },
 150         { Opt_noresvport, "noresvport" },
 151         { Opt_fscache, "fsc" },
 152         { Opt_nofscache, "nofsc" },
 153         { Opt_migration, "migration" },
 154         { Opt_nomigration, "nomigration" },
 155
 156         { Opt_port, "port=%s" },
 157         { Opt_rsize, "rsize=%s" },
 158         { Opt_wsize, "wsize=%s" },
 159         { Opt_bsize, "bsize=%s" },
 160         { Opt_timeo, "timeo=%s" },
 161         { Opt_retrans, "retrans=%s" },
 162         { Opt_acregmin, "acregmin=%s" },
 163         { Opt_acregmax, "acregmax=%s" },
 164         { Opt_acdirmin, "acdirmin=%s" },
 165         { Opt_acdirmax, "acdirmax=%s" },
 166         { Opt_actimeo, "actimeo=%s" },
 167         { Opt_namelen, "namlen=%s" },
 168         { Opt_mountport, "mountport=%s" },
 169         { Opt_mountvers, "mountvers=%s" },
 170         { Opt_minorversion, "minorversion=%s" },
 171
 172         { Opt_nfsvers, "nfsvers=%s" },
 173         { Opt_nfsvers, "vers=%s" },
 174
 175         { Opt_sec, "sec=%s" },
 176         { Opt_proto, "proto=%s" },
 177         { Opt_mountproto, "mountproto=%s" },
 178         { Opt_addr, "addr=%s" },
 179         { Opt_clientaddr, "clientaddr=%s" },
 180         { Opt_mounthost, "mounthost=%s" },
 181         { Opt_mountaddr, "mountaddr=%s" },
 182
 183         { Opt_lookupcache, "lookupcache=%s" },
 184         { Opt_fscache_uniq, "fsc=%s" },
 185         { Opt_local_lock, "local_lock=%s" },
 186
 187         /* The following needs to be listed after all other options */
 188         { Opt_nfsvers, "v%s" },
 189
 190         { Opt_err, NULL }
 191 };
 192
 193 enum {
 194         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 195
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205
 206         { Opt_xprt_err, NULL }
 207 };
 208
 209 enum {
 210         Opt_sec_none, Opt_sec_sys,
 211         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 212         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 213         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 214
 215         Opt_sec_err
 216 };
 217
 218 static const match_table_t nfs_secflavor_tokens = {
 219         { Opt_sec_none, "none" },
 220         { Opt_sec_none, "null" },
 221         { Opt_sec_sys, "sys" },
 222
 223         { Opt_sec_krb5, "krb5" },
 224         { Opt_sec_krb5i, "krb5i" },
 225         { Opt_sec_krb5p, "krb5p" },
 226
 227         { Opt_sec_lkey, "lkey" },
 228         { Opt_sec_lkeyi, "lkeyi" },
 229         { Opt_sec_lkeyp, "lkeyp" },
 230
 231         { Opt_sec_spkm, "spkm3" },
 232         { Opt_sec_spkmi, "spkm3i" },
 233         { Opt_sec_spkmp, "spkm3p" },
 234
 235         { Opt_sec_err, NULL }
 236 };
 237
 238 enum {
 239         Opt_lookupcache_all, Opt_lookupcache_positive,
 240         Opt_lookupcache_none,
 241
 242         Opt_lookupcache_err
 243 };
 244
 245 static match_table_t nfs_lookupcache_tokens = {
 246         { Opt_lookupcache_all, "all" },
 247         { Opt_lookupcache_positive, "pos" },
 248         { Opt_lookupcache_positive, "positive" },
 249         { Opt_lookupcache_none, "none" },
 250
 251         { Opt_lookupcache_err, NULL }
 252 };
 253
 254 enum {
 255         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 256         Opt_local_lock_none,
 257
 258         Opt_local_lock_err
 259 };
 260
 261 static match_table_t nfs_local_lock_tokens = {
 262         { Opt_local_lock_all, "all" },
 263         { Opt_local_lock_flock, "flock" },
 264         { Opt_local_lock_posix, "posix" },
 265         { Opt_local_lock_none, "none" },
 266
 267         { Opt_local_lock_err, NULL }
 268 };
 269
 270 enum {
 271         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 272         Opt_vers_4_1,
 273
 274         Opt_vers_err
 275 };
 276
 277 static match_table_t nfs_vers_tokens = {
 278         { Opt_vers_2, "2" },
 279         { Opt_vers_3, "3" },
 280         { Opt_vers_4, "4" },
 281         { Opt_vers_4_0, "4.0" },
 282         { Opt_vers_4_1, "4.1" },
 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 EXPORT_SYMBOL_GPL(nfs_fs_type);
 298
 299 struct file_system_type nfs_xdev_fs_type = {
 300         .owner          = THIS_MODULE,
 301         .name           = "nfs",
 302         .mount          = nfs_xdev_mount,
 303         .kill_sb        = nfs_kill_super,
 304         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 305 };
 306
 307 const struct super_operations nfs_sops = {
 308         .alloc_inode    = nfs_alloc_inode,
 309         .destroy_inode  = nfs_destroy_inode,
 310         .write_inode    = nfs_write_inode,
 311         .drop_inode     = nfs_drop_inode,
 312         .put_super      = nfs_put_super,
 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 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 337
 338 static int __init register_nfs4_fs(void)
 339 {
 340         return register_filesystem(&nfs4_fs_type);
 341 }
 342
 343 static void unregister_nfs4_fs(void)
 344 {
 345         unregister_filesystem(&nfs4_fs_type);
 346 }
 347 #else
 348 static int __init register_nfs4_fs(void)
 349 {
 350         return 0;
 351 }
 352
 353 static void unregister_nfs4_fs(void)
 354 {
 355 }
 356 #endif
 357
 358 static struct shrinker acl_shrinker = {
 359         .shrink         = nfs_access_cache_shrinker,
 360         .seeks          = DEFAULT_SEEKS,
 361 };
 362
 363 /*
 364  * Register the NFS filesystems
 365  */
 366 int __init register_nfs_fs(void)
 367 {
 368         int ret;
 369
 370         ret = register_filesystem(&nfs_fs_type);
 371         if (ret < 0)
 372                 goto error_0;
 373
 374         ret = register_nfs4_fs();
 375         if (ret < 0)
 376                 goto error_1;
 377
 378         ret = nfs_register_sysctl();
 379         if (ret < 0)
 380                 goto error_2;
 381         register_shrinker(&acl_shrinker);
 382         return 0;
 383
 384 error_2:
 385         unregister_nfs4_fs();
 386 error_1:
 387         unregister_filesystem(&nfs_fs_type);
 388 error_0:
 389         return ret;
 390 }
 391
 392 /*
 393  * Unregister the NFS filesystems
 394  */
 395 void __exit unregister_nfs_fs(void)
 396 {
 397         unregister_shrinker(&acl_shrinker);
 398         nfs_unregister_sysctl();
 399         unregister_nfs4_fs();
 400         unregister_filesystem(&nfs_fs_type);
 401 }
 402
 403 void nfs_sb_active(struct super_block *sb)
 404 {
 405         struct nfs_server *server = NFS_SB(sb);
 406
 407         if (atomic_inc_return(&server->active) == 1)
 408                 atomic_inc(&sb->s_active);
 409 }
 410 EXPORT_SYMBOL_GPL(nfs_sb_active);
 411
 412 void nfs_sb_deactive(struct super_block *sb)
 413 {
 414         struct nfs_server *server = NFS_SB(sb);
 415
 416         if (atomic_dec_and_test(&server->active))
 417                 deactivate_super(sb);
 418 }
 419 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 420
 421 /*
 422  * Deliver file system statistics to userspace
 423  */
 424 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 425 {
 426         struct nfs_server *server = NFS_SB(dentry->d_sb);
 427         unsigned char blockbits;
 428         unsigned long blockres;
 429         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 430         struct nfs_fsstat res;
 431         int error = -ENOMEM;
 432
 433         res.fattr = nfs_alloc_fattr();
 434         if (res.fattr == NULL)
 435                 goto out_err;
 436
 437         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 438         if (unlikely(error == -ESTALE)) {
 439                 struct dentry *pd_dentry;
 440
 441                 pd_dentry = dget_parent(dentry);
 442                 if (pd_dentry != NULL) {
 443                         nfs_zap_caches(pd_dentry->d_inode);
 444                         dput(pd_dentry);
 445                 }
 446         }
 447         nfs_free_fattr(res.fattr);
 448         if (error < 0)
 449                 goto out_err;
 450
 451         buf->f_type = NFS_SUPER_MAGIC;
 452
 453         /*
 454          * Current versions of glibc do not correctly handle the
 455          * case where f_frsize != f_bsize.  Eventually we want to
 456          * report the value of wtmult in this field.
 457          */
 458         buf->f_frsize = dentry->d_sb->s_blocksize;
 459
 460         /*
 461          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 462          * are reported in units of f_frsize.  Linux hasn't had
 463          * an f_frsize field in its statfs struct until recently,
 464          * thus historically Linux's sys_statfs reports these
 465          * fields in units of f_bsize.
 466          */
 467         buf->f_bsize = dentry->d_sb->s_blocksize;
 468         blockbits = dentry->d_sb->s_blocksize_bits;
 469         blockres = (1 << blockbits) - 1;
 470         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 471         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 472         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 473
 474         buf->f_files = res.tfiles;
 475         buf->f_ffree = res.afiles;
 476
 477         buf->f_namelen = server->namelen;
 478
 479         return 0;
 480
 481  out_err:
 482         dprintk("%s: statfs error = %d\n", __func__, -error);
 483         return error;
 484 }
 485 EXPORT_SYMBOL_GPL(nfs_statfs);
 486
 487 /*
 488  * Map the security flavour number to a name
 489  */
 490 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 491 {
 492         static const struct {
 493                 rpc_authflavor_t flavour;
 494                 const char *str;
 495         } sec_flavours[] = {
 496                 { RPC_AUTH_NULL, "null" },
 497                 { RPC_AUTH_UNIX, "sys" },
 498                 { RPC_AUTH_GSS_KRB5, "krb5" },
 499                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 500                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 501                 { RPC_AUTH_GSS_LKEY, "lkey" },
 502                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 503                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 504                 { RPC_AUTH_GSS_SPKM, "spkm" },
 505                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 506                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 507                 { UINT_MAX, "unknown" }
 508         };
 509         int i;
 510
 511         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 512                 if (sec_flavours[i].flavour == flavour)
 513                         break;
 514         }
 515         return sec_flavours[i].str;
 516 }
 517
 518 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 519                                   int showdefaults)
 520 {
 521         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 522
 523         seq_printf(m, ",mountproto=");
 524         switch (sap->sa_family) {
 525         case AF_INET:
 526                 switch (nfss->mountd_protocol) {
 527                 case IPPROTO_UDP:
 528                         seq_printf(m, RPCBIND_NETID_UDP);
 529                         break;
 530                 case IPPROTO_TCP:
 531                         seq_printf(m, RPCBIND_NETID_TCP);
 532                         break;
 533                 default:
 534                         if (showdefaults)
 535                                 seq_printf(m, "auto");
 536                 }
 537                 break;
 538         case AF_INET6:
 539                 switch (nfss->mountd_protocol) {
 540                 case IPPROTO_UDP:
 541                         seq_printf(m, RPCBIND_NETID_UDP6);
 542                         break;
 543                 case IPPROTO_TCP:
 544                         seq_printf(m, RPCBIND_NETID_TCP6);
 545                         break;
 546                 default:
 547                         if (showdefaults)
 548                                 seq_printf(m, "auto");
 549                 }
 550                 break;
 551         default:
 552                 if (showdefaults)
 553                         seq_printf(m, "auto");
 554         }
 555 }
 556
 557 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 558                                     int showdefaults)
 559 {
 560         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 561
 562         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 563                 return;
 564
 565         switch (sap->sa_family) {
 566         case AF_INET: {
 567                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 568                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 569                 break;
 570         }
 571         case AF_INET6: {
 572                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 573                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 574                 break;
 575         }
 576         default:
 577                 if (showdefaults)
 578                         seq_printf(m, ",mountaddr=unspecified");
 579         }
 580
 581         if (nfss->mountd_version || showdefaults)
 582                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 583         if ((nfss->mountd_port &&
 584                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 585                 showdefaults)
 586                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 587
 588         nfs_show_mountd_netid(m, nfss, showdefaults);
 589 }
 590
 591 #if IS_ENABLED(CONFIG_NFS_V4)
 592 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 593                                     int showdefaults)
 594 {
 595         struct nfs_client *clp = nfss->nfs_client;
 596
 597         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 598 }
 599 #else
 600 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 601                                     int showdefaults)
 602 {
 603 }
 604 #endif
 605
 606 static void nfs_show_nfs_version(struct seq_file *m,
 607                 unsigned int version,
 608                 unsigned int minorversion)
 609 {
 610         seq_printf(m, ",vers=%u", version);
 611         if (version == 4)
 612                 seq_printf(m, ".%u", minorversion);
 613 }
 614
 615 /*
 616  * Describe the mount options in force on this server representation
 617  */
 618 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 619                                    int showdefaults)
 620 {
 621         static const struct proc_nfs_info {
 622                 int flag;
 623                 const char *str;
 624                 const char *nostr;
 625         } nfs_info[] = {
 626                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 627                 { NFS_MOUNT_POSIX, ",posix", "" },
 628                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 629                 { NFS_MOUNT_NOAC, ",noac", "" },
 630                 { NFS_MOUNT_NONLM, ",nolock", "" },
 631                 { NFS_MOUNT_NOACL, ",noacl", "" },
 632                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 633                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 634                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 635                 { 0, NULL, NULL }
 636         };
 637         const struct proc_nfs_info *nfs_infop;
 638         struct nfs_client *clp = nfss->nfs_client;
 639         u32 version = clp->rpc_ops->version;
 640         int local_flock, local_fcntl;
 641
 642         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 643         seq_printf(m, ",rsize=%u", nfss->rsize);
 644         seq_printf(m, ",wsize=%u", nfss->wsize);
 645         if (nfss->bsize != 0)
 646                 seq_printf(m, ",bsize=%u", nfss->bsize);
 647         seq_printf(m, ",namlen=%u", nfss->namelen);
 648         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 649                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 650         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 651                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 652         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 653                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 654         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 655                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 656         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 657                 if (nfss->flags & nfs_infop->flag)
 658                         seq_puts(m, nfs_infop->str);
 659                 else
 660                         seq_puts(m, nfs_infop->nostr);
 661         }
 662         rcu_read_lock();
 663         seq_printf(m, ",proto=%s",
 664                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 665         rcu_read_unlock();
 666         if (version == 4) {
 667                 if (nfss->port != NFS_PORT)
 668                         seq_printf(m, ",port=%u", nfss->port);
 669         } else
 670                 if (nfss->port)
 671                         seq_printf(m, ",port=%u", nfss->port);
 672
 673         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 674         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 675         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 676
 677         if (version != 4)
 678                 nfs_show_mountd_options(m, nfss, showdefaults);
 679         else
 680                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 681
 682         if (nfss->options & NFS_OPTION_FSCACHE)
 683                 seq_printf(m, ",fsc");
 684
 685         if (nfss->options & NFS_OPTION_MIGRATION)
 686                 seq_printf(m, ",migration");
 687
 688         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 689                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 690                         seq_printf(m, ",lookupcache=none");
 691                 else
 692                         seq_printf(m, ",lookupcache=pos");
 693         }
 694
 695         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 696         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 697
 698         if (!local_flock && !local_fcntl)
 699                 seq_printf(m, ",local_lock=none");
 700         else if (local_flock && local_fcntl)
 701                 seq_printf(m, ",local_lock=all");
 702         else if (local_flock)
 703                 seq_printf(m, ",local_lock=flock");
 704         else
 705                 seq_printf(m, ",local_lock=posix");
 706 }
 707
 708 /*
 709  * Describe the mount options on this VFS mountpoint
 710  */
 711 int nfs_show_options(struct seq_file *m, struct dentry *root)
 712 {
 713         struct nfs_server *nfss = NFS_SB(root->d_sb);
 714
 715         nfs_show_mount_options(m, nfss, 0);
 716
 717         rcu_read_lock();
 718         seq_printf(m, ",addr=%s",
 719                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 720                                                         RPC_DISPLAY_ADDR));
 721         rcu_read_unlock();
 722
 723         return 0;
 724 }
 725 EXPORT_SYMBOL_GPL(nfs_show_options);
 726
 727 #if IS_ENABLED(CONFIG_NFS_V4)
 728 #ifdef CONFIG_NFS_V4_1
 729 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 730 {
 731         if (nfs4_has_session(server->nfs_client))
 732                 seq_printf(m, ",sessions");
 733 }
 734 #else
 735 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 736 #endif
 737 #endif
 738
 739 #ifdef CONFIG_NFS_V4_1
 740 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 741 {
 742         seq_printf(m, ",pnfs=");
 743         if (server->pnfs_curr_ld)
 744                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 745         else
 746                 seq_printf(m, "not configured");
 747 }
 748
 749 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 750 {
 751         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 752                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 753                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 754                            "date='%llu,%u'",
 755                            impl_id->name, impl_id->domain,
 756                            impl_id->date.seconds, impl_id->date.nseconds);
 757         }
 758 }
 759 #else
 760 #if IS_ENABLED(CONFIG_NFS_V4)
 761 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 762 {
 763 }
 764 #endif
 765 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 766 {
 767 }
 768 #endif
 769
 770 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 771 {
 772         char *page = (char *) __get_free_page(GFP_KERNEL);
 773         char *devname, *dummy;
 774         int err = 0;
 775         if (!page)
 776                 return -ENOMEM;
 777         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 778         if (IS_ERR(devname))
 779                 err = PTR_ERR(devname);
 780         else
 781                 seq_escape(m, devname, " \t\n\\");
 782         free_page((unsigned long)page);
 783         return err;
 784 }
 785 EXPORT_SYMBOL_GPL(nfs_show_devname);
 786
 787 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 788 {
 789         seq_puts(m, "/");
 790         return 0;
 791 }
 792 EXPORT_SYMBOL_GPL(nfs_show_path);
 793
 794 /*
 795  * Present statistical information for this VFS mountpoint
 796  */
 797 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 798 {
 799         int i, cpu;
 800         struct nfs_server *nfss = NFS_SB(root->d_sb);
 801         struct rpc_auth *auth = nfss->client->cl_auth;
 802         struct nfs_iostats totals = { };
 803
 804         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 805
 806         /*
 807          * Display all mount option settings
 808          */
 809         seq_printf(m, "\n\topts:\t");
 810         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 811         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 812         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 813         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 814         nfs_show_mount_options(m, nfss, 1);
 815
 816         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 817
 818         show_implementation_id(m, nfss);
 819
 820         seq_printf(m, "\n\tcaps:\t");
 821         seq_printf(m, "caps=0x%x", nfss->caps);
 822         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 823         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 824         seq_printf(m, ",bsize=%u", nfss->bsize);
 825         seq_printf(m, ",namlen=%u", nfss->namelen);
 826
 827 #if IS_ENABLED(CONFIG_NFS_V4)
 828         if (nfss->nfs_client->rpc_ops->version == 4) {
 829                 seq_printf(m, "\n\tnfsv4:\t");
 830                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 831                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 832                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 833                 show_sessions(m, nfss);
 834                 show_pnfs(m, nfss);
 835         }
 836 #endif
 837
 838         /*
 839          * Display security flavor in effect for this mount
 840          */
 841         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 842         if (auth->au_flavor)
 843                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 844
 845         /*
 846          * Display superblock I/O counters
 847          */
 848         for_each_possible_cpu(cpu) {
 849                 struct nfs_iostats *stats;
 850
 851                 preempt_disable();
 852                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 853
 854                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 855                         totals.events[i] += stats->events[i];
 856                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 857                         totals.bytes[i] += stats->bytes[i];
 858 #ifdef CONFIG_NFS_FSCACHE
 859                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 860                         totals.fscache[i] += stats->fscache[i];
 861 #endif
 862
 863                 preempt_enable();
 864         }
 865
 866         seq_printf(m, "\n\tevents:\t");
 867         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 868                 seq_printf(m, "%lu ", totals.events[i]);
 869         seq_printf(m, "\n\tbytes:\t");
 870         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 871                 seq_printf(m, "%Lu ", totals.bytes[i]);
 872 #ifdef CONFIG_NFS_FSCACHE
 873         if (nfss->options & NFS_OPTION_FSCACHE) {
 874                 seq_printf(m, "\n\tfsc:\t");
 875                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 876                         seq_printf(m, "%Lu ", totals.bytes[i]);
 877         }
 878 #endif
 879         seq_printf(m, "\n");
 880
 881         rpc_print_iostats(m, nfss->client);
 882
 883         return 0;
 884 }
 885 EXPORT_SYMBOL_GPL(nfs_show_stats);
 886
 887 /*
 888  * Begin unmount by attempting to remove all automounted mountpoints we added
 889  * in response to xdev traversals and referrals
 890  */
 891 void nfs_umount_begin(struct super_block *sb)
 892 {
 893         struct nfs_server *server;
 894         struct rpc_clnt *rpc;
 895
 896         server = NFS_SB(sb);
 897         /* -EIO all pending I/O */
 898         rpc = server->client_acl;
 899         if (!IS_ERR(rpc))
 900                 rpc_killall_tasks(rpc);
 901         rpc = server->client;
 902         if (!IS_ERR(rpc))
 903                 rpc_killall_tasks(rpc);
 904 }
 905 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 906
 907 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 908 {
 909         struct nfs_parsed_mount_data *data;
 910
 911         data = kzalloc(sizeof(*data), GFP_KERNEL);
 912         if (data) {
 913                 data->acregmin          = NFS_DEF_ACREGMIN;
 914                 data->acregmax          = NFS_DEF_ACREGMAX;
 915                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 916                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 917                 data->mount_server.port = NFS_UNSPEC_PORT;
 918                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 919                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 920                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 921                 data->auth_flavor_len   = 1;
 922                 data->minorversion      = 0;
 923                 data->need_mount        = true;
 924                 data->net               = current->nsproxy->net_ns;
 925                 security_init_mnt_opts(&data->lsm_opts);
 926         }
 927         return data;
 928 }
 929
 930 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 931 {
 932         if (data) {
 933                 kfree(data->client_address);
 934                 kfree(data->mount_server.hostname);
 935                 kfree(data->nfs_server.export_path);
 936                 kfree(data->nfs_server.hostname);
 937                 kfree(data->fscache_uniq);
 938                 security_free_mnt_opts(&data->lsm_opts);
 939                 kfree(data);
 940         }
 941 }
 942
 943 /*
 944  * Sanity-check a server address provided by the mount command.
 945  *
 946  * Address family must be initialized, and address must not be
 947  * the ANY address for that family.
 948  */
 949 static int nfs_verify_server_address(struct sockaddr *addr)
 950 {
 951         switch (addr->sa_family) {
 952         case AF_INET: {
 953                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 954                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 955         }
 956         case AF_INET6: {
 957                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 958                 return !ipv6_addr_any(sa);
 959         }
 960         }
 961
 962         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 963         return 0;
 964 }
 965
 966 /*
 967  * Select between a default port value and a user-specified port value.
 968  * If a zero value is set, then autobind will be used.
 969  */
 970 static void nfs_set_port(struct sockaddr *sap, int *port,
 971                                  const unsigned short default_port)
 972 {
 973         if (*port == NFS_UNSPEC_PORT)
 974                 *port = default_port;
 975
 976         rpc_set_port(sap, *port);
 977 }
 978
 979 /*
 980  * Sanity check the NFS transport protocol.
 981  *
 982  */
 983 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 984 {
 985         switch (mnt->nfs_server.protocol) {
 986         case XPRT_TRANSPORT_UDP:
 987         case XPRT_TRANSPORT_TCP:
 988         case XPRT_TRANSPORT_RDMA:
 989                 break;
 990         default:
 991                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 992         }
 993 }
 994
 995 /*
 996  * For text based NFSv2/v3 mounts, the mount protocol transport default
 997  * settings should depend upon the specified NFS transport.
 998  */
 999 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1000 {
1001         nfs_validate_transport_protocol(mnt);
1002
1003         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1004             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1005                         return;
1006         switch (mnt->nfs_server.protocol) {
1007         case XPRT_TRANSPORT_UDP:
1008                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1009                 break;
1010         case XPRT_TRANSPORT_TCP:
1011         case XPRT_TRANSPORT_RDMA:
1012                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1013         }
1014 }
1015
1016 /*
1017  * Parse the value of the 'sec=' option.
1018  */
1019 static int nfs_parse_security_flavors(char *value,
1020                                       struct nfs_parsed_mount_data *mnt)
1021 {
1022         substring_t args[MAX_OPT_ARGS];
1023
1024         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1025
1026         switch (match_token(value, nfs_secflavor_tokens, args)) {
1027         case Opt_sec_none:
1028                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1029                 break;
1030         case Opt_sec_sys:
1031                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1032                 break;
1033         case Opt_sec_krb5:
1034                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1035                 break;
1036         case Opt_sec_krb5i:
1037                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1038                 break;
1039         case Opt_sec_krb5p:
1040                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1041                 break;
1042         case Opt_sec_lkey:
1043                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1044                 break;
1045         case Opt_sec_lkeyi:
1046                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1047                 break;
1048         case Opt_sec_lkeyp:
1049                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1050                 break;
1051         case Opt_sec_spkm:
1052                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1053                 break;
1054         case Opt_sec_spkmi:
1055                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1056                 break;
1057         case Opt_sec_spkmp:
1058                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1059                 break;
1060         default:
1061                 return 0;
1062         }
1063
1064         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1065         mnt->auth_flavor_len = 1;
1066         return 1;
1067 }
1068
1069 static int nfs_parse_version_string(char *string,
1070                 struct nfs_parsed_mount_data *mnt,
1071                 substring_t *args)
1072 {
1073         mnt->flags &= ~NFS_MOUNT_VER3;
1074         switch (match_token(string, nfs_vers_tokens, args)) {
1075         case Opt_vers_2:
1076                 mnt->version = 2;
1077                 break;
1078         case Opt_vers_3:
1079                 mnt->flags |= NFS_MOUNT_VER3;
1080                 mnt->version = 3;
1081                 break;
1082         case Opt_vers_4:
1083                 /* Backward compatibility option. In future,
1084                  * the mount program should always supply
1085                  * a NFSv4 minor version number.
1086                  */
1087                 mnt->version = 4;
1088                 break;
1089         case Opt_vers_4_0:
1090                 mnt->version = 4;
1091                 mnt->minorversion = 0;
1092                 break;
1093         case Opt_vers_4_1:
1094                 mnt->version = 4;
1095                 mnt->minorversion = 1;
1096                 break;
1097         default:
1098                 return 0;
1099         }
1100         return 1;
1101 }
1102
1103 static int nfs_get_option_str(substring_t args[], char **option)
1104 {
1105         kfree(*option);
1106         *option = match_strdup(args);
1107         return !*option;
1108 }
1109
1110 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1111 {
1112         int rc;
1113         char *string;
1114
1115         string = match_strdup(args);
1116         if (string == NULL)
1117                 return -ENOMEM;
1118         rc = kstrtoul(string, 10, option);
1119         kfree(string);
1120
1121         return rc;
1122 }
1123
1124 /*
1125  * Error-check and convert a string of mount options from user space into
1126  * a data structure.  The whole mount string is processed; bad options are
1127  * skipped as they are encountered.  If there were no errors, return 1;
1128  * otherwise return 0 (zero).
1129  */
1130 static int nfs_parse_mount_options(char *raw,
1131                                    struct nfs_parsed_mount_data *mnt)
1132 {
1133         char *p, *string, *secdata;
1134         int rc, sloppy = 0, invalid_option = 0;
1135         unsigned short protofamily = AF_UNSPEC;
1136         unsigned short mountfamily = AF_UNSPEC;
1137
1138         if (!raw) {
1139                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1140                 return 1;
1141         }
1142         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1143
1144         secdata = alloc_secdata();
1145         if (!secdata)
1146                 goto out_nomem;
1147
1148         rc = security_sb_copy_data(raw, secdata);
1149         if (rc)
1150                 goto out_security_failure;
1151
1152         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1153         if (rc)
1154                 goto out_security_failure;
1155
1156         free_secdata(secdata);
1157
1158         while ((p = strsep(&raw, ",")) != NULL) {
1159                 substring_t args[MAX_OPT_ARGS];
1160                 unsigned long option;
1161                 int token;
1162
1163                 if (!*p)
1164                         continue;
1165
1166                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1167
1168                 token = match_token(p, nfs_mount_option_tokens, args);
1169                 switch (token) {
1170
1171                 /*
1172                  * boolean options:  foo/nofoo
1173                  */
1174                 case Opt_soft:
1175                         mnt->flags |= NFS_MOUNT_SOFT;
1176                         break;
1177                 case Opt_hard:
1178                         mnt->flags &= ~NFS_MOUNT_SOFT;
1179                         break;
1180                 case Opt_posix:
1181                         mnt->flags |= NFS_MOUNT_POSIX;
1182                         break;
1183                 case Opt_noposix:
1184                         mnt->flags &= ~NFS_MOUNT_POSIX;
1185                         break;
1186                 case Opt_cto:
1187                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1188                         break;
1189                 case Opt_nocto:
1190                         mnt->flags |= NFS_MOUNT_NOCTO;
1191                         break;
1192                 case Opt_ac:
1193                         mnt->flags &= ~NFS_MOUNT_NOAC;
1194                         break;
1195                 case Opt_noac:
1196                         mnt->flags |= NFS_MOUNT_NOAC;
1197                         break;
1198                 case Opt_lock:
1199                         mnt->flags &= ~NFS_MOUNT_NONLM;
1200                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1201                                         NFS_MOUNT_LOCAL_FCNTL);
1202                         break;
1203                 case Opt_nolock:
1204                         mnt->flags |= NFS_MOUNT_NONLM;
1205                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1206                                        NFS_MOUNT_LOCAL_FCNTL);
1207                         break;
1208                 case Opt_udp:
1209                         mnt->flags &= ~NFS_MOUNT_TCP;
1210                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1211                         break;
1212                 case Opt_tcp:
1213                         mnt->flags |= NFS_MOUNT_TCP;
1214                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1215                         break;
1216                 case Opt_rdma:
1217                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1218                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1219                         xprt_load_transport(p);
1220                         break;
1221                 case Opt_acl:
1222                         mnt->flags &= ~NFS_MOUNT_NOACL;
1223                         break;
1224                 case Opt_noacl:
1225                         mnt->flags |= NFS_MOUNT_NOACL;
1226                         break;
1227                 case Opt_rdirplus:
1228                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1229                         break;
1230                 case Opt_nordirplus:
1231                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1232                         break;
1233                 case Opt_sharecache:
1234                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1235                         break;
1236                 case Opt_nosharecache:
1237                         mnt->flags |= NFS_MOUNT_UNSHARED;
1238                         break;
1239                 case Opt_resvport:
1240                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1241                         break;
1242                 case Opt_noresvport:
1243                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1244                         break;
1245                 case Opt_fscache:
1246                         mnt->options |= NFS_OPTION_FSCACHE;
1247                         kfree(mnt->fscache_uniq);
1248                         mnt->fscache_uniq = NULL;
1249                         break;
1250                 case Opt_nofscache:
1251                         mnt->options &= ~NFS_OPTION_FSCACHE;
1252                         kfree(mnt->fscache_uniq);
1253                         mnt->fscache_uniq = NULL;
1254                         break;
1255                 case Opt_migration:
1256                         mnt->options |= NFS_OPTION_MIGRATION;
1257                         break;
1258                 case Opt_nomigration:
1259                         mnt->options &= NFS_OPTION_MIGRATION;
1260                         break;
1261
1262                 /*
1263                  * options that take numeric values
1264                  */
1265                 case Opt_port:
1266                         if (nfs_get_option_ul(args, &option) ||
1267                             option > USHRT_MAX)
1268                                 goto out_invalid_value;
1269                         mnt->nfs_server.port = option;
1270                         break;
1271                 case Opt_rsize:
1272                         if (nfs_get_option_ul(args, &option))
1273                                 goto out_invalid_value;
1274                         mnt->rsize = option;
1275                         break;
1276                 case Opt_wsize:
1277                         if (nfs_get_option_ul(args, &option))
1278                                 goto out_invalid_value;
1279                         mnt->wsize = option;
1280                         break;
1281                 case Opt_bsize:
1282                         if (nfs_get_option_ul(args, &option))
1283                                 goto out_invalid_value;
1284                         mnt->bsize = option;
1285                         break;
1286                 case Opt_timeo:
1287                         if (nfs_get_option_ul(args, &option) || option == 0)
1288                                 goto out_invalid_value;
1289                         mnt->timeo = option;
1290                         break;
1291                 case Opt_retrans:
1292                         if (nfs_get_option_ul(args, &option) || option == 0)
1293                                 goto out_invalid_value;
1294                         mnt->retrans = option;
1295                         break;
1296                 case Opt_acregmin:
1297                         if (nfs_get_option_ul(args, &option))
1298                                 goto out_invalid_value;
1299                         mnt->acregmin = option;
1300                         break;
1301                 case Opt_acregmax:
1302                         if (nfs_get_option_ul(args, &option))
1303                                 goto out_invalid_value;
1304                         mnt->acregmax = option;
1305                         break;
1306                 case Opt_acdirmin:
1307                         if (nfs_get_option_ul(args, &option))
1308                                 goto out_invalid_value;
1309                         mnt->acdirmin = option;
1310                         break;
1311                 case Opt_acdirmax:
1312                         if (nfs_get_option_ul(args, &option))
1313                                 goto out_invalid_value;
1314                         mnt->acdirmax = option;
1315                         break;
1316                 case Opt_actimeo:
1317                         if (nfs_get_option_ul(args, &option))
1318                                 goto out_invalid_value;
1319                         mnt->acregmin = mnt->acregmax =
1320                         mnt->acdirmin = mnt->acdirmax = option;
1321                         break;
1322                 case Opt_namelen:
1323                         if (nfs_get_option_ul(args, &option))
1324                                 goto out_invalid_value;
1325                         mnt->namlen = option;
1326                         break;
1327                 case Opt_mountport:
1328                         if (nfs_get_option_ul(args, &option) ||
1329                             option > USHRT_MAX)
1330                                 goto out_invalid_value;
1331                         mnt->mount_server.port = option;
1332                         break;
1333                 case Opt_mountvers:
1334                         if (nfs_get_option_ul(args, &option) ||
1335                             option < NFS_MNT_VERSION ||
1336                             option > NFS_MNT3_VERSION)
1337                                 goto out_invalid_value;
1338                         mnt->mount_server.version = option;
1339                         break;
1340                 case Opt_minorversion:
1341                         if (nfs_get_option_ul(args, &option))
1342                                 goto out_invalid_value;
1343                         if (option > NFS4_MAX_MINOR_VERSION)
1344                                 goto out_invalid_value;
1345                         mnt->minorversion = option;
1346                         break;
1347
1348                 /*
1349                  * options that take text values
1350                  */
1351                 case Opt_nfsvers:
1352                         string = match_strdup(args);
1353                         if (string == NULL)
1354                                 goto out_nomem;
1355                         rc = nfs_parse_version_string(string, mnt, args);
1356                         kfree(string);
1357                         if (!rc)
1358                                 goto out_invalid_value;
1359                         break;
1360                 case Opt_sec:
1361                         string = match_strdup(args);
1362                         if (string == NULL)
1363                                 goto out_nomem;
1364                         rc = nfs_parse_security_flavors(string, mnt);
1365                         kfree(string);
1366                         if (!rc) {
1367                                 dfprintk(MOUNT, "NFS:   unrecognized "
1368                                                 "security flavor\n");
1369                                 return 0;
1370                         }
1371                         break;
1372                 case Opt_proto:
1373                         string = match_strdup(args);
1374                         if (string == NULL)
1375                                 goto out_nomem;
1376                         token = match_token(string,
1377                                             nfs_xprt_protocol_tokens, args);
1378
1379                         protofamily = AF_INET;
1380                         switch (token) {
1381                         case Opt_xprt_udp6:
1382                                 protofamily = AF_INET6;
1383                         case Opt_xprt_udp:
1384                                 mnt->flags &= ~NFS_MOUNT_TCP;
1385                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1386                                 break;
1387                         case Opt_xprt_tcp6:
1388                                 protofamily = AF_INET6;
1389                         case Opt_xprt_tcp:
1390                                 mnt->flags |= NFS_MOUNT_TCP;
1391                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1392                                 break;
1393                         case Opt_xprt_rdma:
1394                                 /* vector side protocols to TCP */
1395                                 mnt->flags |= NFS_MOUNT_TCP;
1396                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1397                                 xprt_load_transport(string);
1398                                 break;
1399                         default:
1400                                 dfprintk(MOUNT, "NFS:   unrecognized "
1401                                                 "transport protocol\n");
1402                                 kfree(string);
1403                                 return 0;
1404                         }
1405                         kfree(string);
1406                         break;
1407                 case Opt_mountproto:
1408                         string = match_strdup(args);
1409                         if (string == NULL)
1410                                 goto out_nomem;
1411                         token = match_token(string,
1412                                             nfs_xprt_protocol_tokens, args);
1413                         kfree(string);
1414
1415                         mountfamily = AF_INET;
1416                         switch (token) {
1417                         case Opt_xprt_udp6:
1418                                 mountfamily = AF_INET6;
1419                         case Opt_xprt_udp:
1420                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1421                                 break;
1422                         case Opt_xprt_tcp6:
1423                                 mountfamily = AF_INET6;
1424                         case Opt_xprt_tcp:
1425                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1426                                 break;
1427                         case Opt_xprt_rdma: /* not used for side protocols */
1428                         default:
1429                                 dfprintk(MOUNT, "NFS:   unrecognized "
1430                                                 "transport protocol\n");
1431                                 return 0;
1432                         }
1433                         break;
1434                 case Opt_addr:
1435                         string = match_strdup(args);
1436                         if (string == NULL)
1437                                 goto out_nomem;
1438                         mnt->nfs_server.addrlen =
1439                                 rpc_pton(mnt->net, string, strlen(string),
1440                                         (struct sockaddr *)
1441                                         &mnt->nfs_server.address,
1442                                         sizeof(mnt->nfs_server.address));
1443                         kfree(string);
1444                         if (mnt->nfs_server.addrlen == 0)
1445                                 goto out_invalid_address;
1446                         break;
1447                 case Opt_clientaddr:
1448                         if (nfs_get_option_str(args, &mnt->client_address))
1449                                 goto out_nomem;
1450                         break;
1451                 case Opt_mounthost:
1452                         if (nfs_get_option_str(args,
1453                                                &mnt->mount_server.hostname))
1454                                 goto out_nomem;
1455                         break;
1456                 case Opt_mountaddr:
1457                         string = match_strdup(args);
1458                         if (string == NULL)
1459                                 goto out_nomem;
1460                         mnt->mount_server.addrlen =
1461                                 rpc_pton(mnt->net, string, strlen(string),
1462                                         (struct sockaddr *)
1463                                         &mnt->mount_server.address,
1464                                         sizeof(mnt->mount_server.address));
1465                         kfree(string);
1466                         if (mnt->mount_server.addrlen == 0)
1467                                 goto out_invalid_address;
1468                         break;
1469                 case Opt_lookupcache:
1470                         string = match_strdup(args);
1471                         if (string == NULL)
1472                                 goto out_nomem;
1473                         token = match_token(string,
1474                                         nfs_lookupcache_tokens, args);
1475                         kfree(string);
1476                         switch (token) {
1477                                 case Opt_lookupcache_all:
1478                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1479                                         break;
1480                                 case Opt_lookupcache_positive:
1481                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1482                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1483                                         break;
1484                                 case Opt_lookupcache_none:
1485                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1486                                         break;
1487                                 default:
1488                                         dfprintk(MOUNT, "NFS:   invalid "
1489                                                         "lookupcache argument\n");
1490                                         return 0;
1491                         };
1492                         break;
1493                 case Opt_fscache_uniq:
1494                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1495                                 goto out_nomem;
1496                         mnt->options |= NFS_OPTION_FSCACHE;
1497                         break;
1498                 case Opt_local_lock:
1499                         string = match_strdup(args);
1500                         if (string == NULL)
1501                                 goto out_nomem;
1502                         token = match_token(string, nfs_local_lock_tokens,
1503                                         args);
1504                         kfree(string);
1505                         switch (token) {
1506                         case Opt_local_lock_all:
1507                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1508                                                NFS_MOUNT_LOCAL_FCNTL);
1509                                 break;
1510                         case Opt_local_lock_flock:
1511                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1512                                 break;
1513                         case Opt_local_lock_posix:
1514                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1515                                 break;
1516                         case Opt_local_lock_none:
1517                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1518                                                 NFS_MOUNT_LOCAL_FCNTL);
1519                                 break;
1520                         default:
1521                                 dfprintk(MOUNT, "NFS:   invalid "
1522                                                 "local_lock argument\n");
1523                                 return 0;
1524                         };
1525                         break;
1526
1527                 /*
1528                  * Special options
1529                  */
1530                 case Opt_sloppy:
1531                         sloppy = 1;
1532                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1533                         break;
1534                 case Opt_userspace:
1535                 case Opt_deprecated:
1536                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1537                                         "'%s'\n", p);
1538                         break;
1539
1540                 default:
1541                         invalid_option = 1;
1542                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1543                                         "'%s'\n", p);
1544                 }
1545         }
1546
1547         if (!sloppy && invalid_option)
1548                 return 0;
1549
1550         if (mnt->minorversion && mnt->version != 4)
1551                 goto out_minorversion_mismatch;
1552
1553         if (mnt->options & NFS_OPTION_MIGRATION &&
1554             mnt->version != 4 && mnt->minorversion != 0)
1555                 goto out_migration_misuse;
1556
1557         /*
1558          * verify that any proto=/mountproto= options match the address
1559          * families in the addr=/mountaddr= options.
1560          */
1561         if (protofamily != AF_UNSPEC &&
1562             protofamily != mnt->nfs_server.address.ss_family)
1563                 goto out_proto_mismatch;
1564
1565         if (mountfamily != AF_UNSPEC) {
1566                 if (mnt->mount_server.addrlen) {
1567                         if (mountfamily != mnt->mount_server.address.ss_family)
1568                                 goto out_mountproto_mismatch;
1569                 } else {
1570                         if (mountfamily != mnt->nfs_server.address.ss_family)
1571                                 goto out_mountproto_mismatch;
1572                 }
1573         }
1574
1575         return 1;
1576
1577 out_mountproto_mismatch:
1578         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1579                          "option\n");
1580         return 0;
1581 out_proto_mismatch:
1582         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1583         return 0;
1584 out_invalid_address:
1585         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1586         return 0;
1587 out_invalid_value:
1588         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1589         return 0;
1590 out_minorversion_mismatch:
1591         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1592                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1593         return 0;
1594 out_migration_misuse:
1595         printk(KERN_INFO
1596                 "NFS: 'migration' not supported for this NFS version\n");
1597         return 0;
1598 out_nomem:
1599         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1600         return 0;
1601 out_security_failure:
1602         free_secdata(secdata);
1603         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1604         return 0;
1605 }
1606
1607 /*
1608  * Match the requested auth flavors with the list returned by
1609  * the server.  Returns zero and sets the mount's authentication
1610  * flavor on success; returns -EACCES if server does not support
1611  * the requested flavor.
1612  */
1613 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1614                              struct nfs_mount_request *request)
1615 {
1616         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1617
1618         /*
1619          * Certain releases of Linux's mountd return an empty
1620          * flavor list.  To prevent behavioral regression with
1621          * these servers (ie. rejecting mounts that used to
1622          * succeed), revert to pre-2.6.32 behavior (no checking)
1623          * if the returned flavor list is empty.
1624          */
1625         if (server_authlist_len == 0)
1626                 return 0;
1627
1628         /*
1629          * We avoid sophisticated negotiating here, as there are
1630          * plenty of cases where we can get it wrong, providing
1631          * either too little or too much security.
1632          *
1633          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1634          * flavor listed first.  However, some servers list
1635          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1636          * preferred default, in args->auth_flavors[0] if user
1637          * didn't specify sec= mount option.
1638          */
1639         for (i = 0; i < args->auth_flavor_len; i++)
1640                 for (j = 0; j < server_authlist_len; j++)
1641                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1642                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1643                                         request->auth_flavs[j]);
1644                                 args->auth_flavors[0] = request->auth_flavs[j];
1645                                 return 0;
1646                         }
1647
1648         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1649         nfs_umount(request);
1650         return -EACCES;
1651 }
1652
1653 /*
1654  * Use the remote server's MOUNT service to request the NFS file handle
1655  * corresponding to the provided path.
1656  */
1657 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1658                              struct nfs_fh *root_fh)
1659 {
1660         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1661         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1662         struct nfs_mount_request request = {
1663                 .sap            = (struct sockaddr *)
1664                                                 &args->mount_server.address,
1665                 .dirpath        = args->nfs_server.export_path,
1666                 .protocol       = args->mount_server.protocol,
1667                 .fh             = root_fh,
1668                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1669                 .auth_flav_len  = &server_authlist_len,
1670                 .auth_flavs     = server_authlist,
1671                 .net            = args->net,
1672         };
1673         int status;
1674
1675         if (args->mount_server.version == 0) {
1676                 switch (args->version) {
1677                         default:
1678                                 args->mount_server.version = NFS_MNT3_VERSION;
1679                                 break;
1680                         case 2:
1681                                 args->mount_server.version = NFS_MNT_VERSION;
1682                 }
1683         }
1684         request.version = args->mount_server.version;
1685
1686         if (args->mount_server.hostname)
1687                 request.hostname = args->mount_server.hostname;
1688         else
1689                 request.hostname = args->nfs_server.hostname;
1690
1691         /*
1692          * Construct the mount server's address.
1693          */
1694         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1695                 memcpy(request.sap, &args->nfs_server.address,
1696                        args->nfs_server.addrlen);
1697                 args->mount_server.addrlen = args->nfs_server.addrlen;
1698         }
1699         request.salen = args->mount_server.addrlen;
1700         nfs_set_port(request.sap, &args->mount_server.port, 0);
1701
1702         /*
1703          * Now ask the mount server to map our export path
1704          * to a file handle.
1705          */
1706         status = nfs_mount(&request);
1707         if (status != 0) {
1708                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1709                                 request.hostname, status);
1710                 return status;
1711         }
1712
1713         /*
1714          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1715          */
1716         if (args->mount_server.version != NFS_MNT3_VERSION)
1717                 return 0;
1718         return nfs_walk_authlist(args, &request);
1719 }
1720
1721 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1722                              struct nfs_mount_info *mount_info,
1723                              struct nfs_subversion *nfs_mod)
1724 {
1725         int status;
1726         struct nfs_server *server;
1727
1728         if (mount_info->parsed->need_mount) {
1729                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1730                 if (status)
1731                         return ERR_PTR(status);
1732         }
1733
1734         /* Get a volume representation */
1735         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1736         if (IS_ERR(server))
1737                 return ERR_CAST(server);
1738
1739         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1740 }
1741 EXPORT_SYMBOL_GPL(nfs_try_mount);
1742
1743 /*
1744  * Split "dev_name" into "hostname:export_path".
1745  *
1746  * The leftmost colon demarks the split between the server's hostname
1747  * and the export path.  If the hostname starts with a left square
1748  * bracket, then it may contain colons.
1749  *
1750  * Note: caller frees hostname and export path, even on error.
1751  */
1752 static int nfs_parse_devname(const char *dev_name,
1753                              char **hostname, size_t maxnamlen,
1754                              char **export_path, size_t maxpathlen)
1755 {
1756         size_t len;
1757         char *end;
1758
1759         /* Is the host name protected with square brakcets? */
1760         if (*dev_name == '[') {
1761                 end = strchr(++dev_name, ']');
1762                 if (end == NULL || end[1] != ':')
1763                         goto out_bad_devname;
1764
1765                 len = end - dev_name;
1766                 end++;
1767         } else {
1768                 char *comma;
1769
1770                 end = strchr(dev_name, ':');
1771                 if (end == NULL)
1772                         goto out_bad_devname;
1773                 len = end - dev_name;
1774
1775                 /* kill possible hostname list: not supported */
1776                 comma = strchr(dev_name, ',');
1777                 if (comma != NULL && comma < end)
1778                         *comma = 0;
1779         }
1780
1781         if (len > maxnamlen)
1782                 goto out_hostname;
1783
1784         /* N.B. caller will free nfs_server.hostname in all cases */
1785         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1786         if (*hostname == NULL)
1787                 goto out_nomem;
1788         len = strlen(++end);
1789         if (len > maxpathlen)
1790                 goto out_path;
1791         *export_path = kstrndup(end, len, GFP_KERNEL);
1792         if (!*export_path)
1793                 goto out_nomem;
1794
1795         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1796         return 0;
1797
1798 out_bad_devname:
1799         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1800         return -EINVAL;
1801
1802 out_nomem:
1803         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1804         return -ENOMEM;
1805
1806 out_hostname:
1807         dfprintk(MOUNT, "NFS: server hostname too long\n");
1808         return -ENAMETOOLONG;
1809
1810 out_path:
1811         dfprintk(MOUNT, "NFS: export pathname too long\n");
1812         return -ENAMETOOLONG;
1813 }
1814
1815 /*
1816  * Validate the NFS2/NFS3 mount data
1817  * - fills in the mount root filehandle
1818  *
1819  * For option strings, user space handles the following behaviors:
1820  *
1821  * + DNS: mapping server host name to IP address ("addr=" option)
1822  *
1823  * + failure mode: how to behave if a mount request can't be handled
1824  *   immediately ("fg/bg" option)
1825  *
1826  * + retry: how often to retry a mount request ("retry=" option)
1827  *
1828  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1829  *   mountproto=tcp after mountproto=udp, and so on
1830  */
1831 static int nfs23_validate_mount_data(void *options,
1832                                      struct nfs_parsed_mount_data *args,
1833                                      struct nfs_fh *mntfh,
1834                                      const char *dev_name)
1835 {
1836         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1837         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1838
1839         if (data == NULL)
1840                 goto out_no_data;
1841
1842         args->version = NFS_DEFAULT_VERSION;
1843         switch (data->version) {
1844         case 1:
1845                 data->namlen = 0;
1846         case 2:
1847                 data->bsize = 0;
1848         case 3:
1849                 if (data->flags & NFS_MOUNT_VER3)
1850                         goto out_no_v3;
1851                 data->root.size = NFS2_FHSIZE;
1852                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1853         case 4:
1854                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1855                         goto out_no_sec;
1856         case 5:
1857                 memset(data->context, 0, sizeof(data->context));
1858         case 6:
1859                 if (data->flags & NFS_MOUNT_VER3) {
1860                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1861                                 goto out_invalid_fh;
1862                         mntfh->size = data->root.size;
1863                         args->version = 3;
1864                 } else {
1865                         mntfh->size = NFS2_FHSIZE;
1866                         args->version = 2;
1867                 }
1868
1869
1870                 memcpy(mntfh->data, data->root.data, mntfh->size);
1871                 if (mntfh->size < sizeof(mntfh->data))
1872                         memset(mntfh->data + mntfh->size, 0,
1873                                sizeof(mntfh->data) - mntfh->size);
1874
1875                 /*
1876                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1877                  * can deal with.
1878                  */
1879                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1880                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1881                 args->rsize             = data->rsize;
1882                 args->wsize             = data->wsize;
1883                 args->timeo             = data->timeo;
1884                 args->retrans           = data->retrans;
1885                 args->acregmin          = data->acregmin;
1886                 args->acregmax          = data->acregmax;
1887                 args->acdirmin          = data->acdirmin;
1888                 args->acdirmax          = data->acdirmax;
1889                 args->need_mount        = false;
1890
1891                 memcpy(sap, &data->addr, sizeof(data->addr));
1892                 args->nfs_server.addrlen = sizeof(data->addr);
1893                 args->nfs_server.port = ntohs(data->addr.sin_port);
1894                 if (!nfs_verify_server_address(sap))
1895                         goto out_no_address;
1896
1897                 if (!(data->flags & NFS_MOUNT_TCP))
1898                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1899                 /* N.B. caller will free nfs_server.hostname in all cases */
1900                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1901                 args->namlen            = data->namlen;
1902                 args->bsize             = data->bsize;
1903
1904                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1905                         args->auth_flavors[0] = data->pseudoflavor;
1906                 if (!args->nfs_server.hostname)
1907                         goto out_nomem;
1908
1909                 if (!(data->flags & NFS_MOUNT_NONLM))
1910                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1911                                          NFS_MOUNT_LOCAL_FCNTL);
1912                 else
1913                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1914                                         NFS_MOUNT_LOCAL_FCNTL);
1915                 /*
1916                  * The legacy version 6 binary mount data from userspace has a
1917                  * field used only to transport selinux information into the
1918                  * the kernel.  To continue to support that functionality we
1919                  * have a touch of selinux knowledge here in the NFS code. The
1920                  * userspace code converted context=blah to just blah so we are
1921                  * converting back to the full string selinux understands.
1922                  */
1923                 if (data->context[0]){
1924 #ifdef CONFIG_SECURITY_SELINUX
1925                         int rc;
1926                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1927                         if (!opts_str)
1928                                 return -ENOMEM;
1929                         strcpy(opts_str, "context=");
1930                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1931                         strcat(opts_str, &data->context[0]);
1932                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1933                         kfree(opts_str);
1934                         if (rc)
1935                                 return rc;
1936 #else
1937                         return -EINVAL;
1938 #endif
1939                 }
1940
1941                 break;
1942         default:
1943                 return NFS_TEXT_DATA;
1944         }
1945
1946 #if !IS_ENABLED(CONFIG_NFS_V3)
1947         if (args->version == 3)
1948                 goto out_v3_not_compiled;
1949 #endif /* !CONFIG_NFS_V3 */
1950
1951         return 0;
1952
1953 out_no_data:
1954         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1955         return -EINVAL;
1956
1957 out_no_v3:
1958         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1959                  data->version);
1960         return -EINVAL;
1961
1962 out_no_sec:
1963         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1964         return -EINVAL;
1965
1966 #if !IS_ENABLED(CONFIG_NFS_V3)
1967 out_v3_not_compiled:
1968         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1969         return -EPROTONOSUPPORT;
1970 #endif /* !CONFIG_NFS_V3 */
1971
1972 out_nomem:
1973         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1974         return -ENOMEM;
1975
1976 out_no_address:
1977         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1978         return -EINVAL;
1979
1980 out_invalid_fh:
1981         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1982         return -EINVAL;
1983 }
1984
1985 #if IS_ENABLED(CONFIG_NFS_V4)
1986 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1987                                    void *options,
1988                                    struct nfs_parsed_mount_data *args,
1989                                    struct nfs_fh *mntfh,
1990                                    const char *dev_name)
1991 {
1992         if (fs_type == &nfs_fs_type)
1993                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1994         return nfs4_validate_mount_data(options, args, dev_name);
1995 }
1996 #else
1997 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1998                                    void *options,
1999                                    struct nfs_parsed_mount_data *args,
2000                                    struct nfs_fh *mntfh,
2001                                    const char *dev_name)
2002 {
2003         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2004 }
2005 #endif
2006
2007 static int nfs_validate_text_mount_data(void *options,
2008                                         struct nfs_parsed_mount_data *args,
2009                                         const char *dev_name)
2010 {
2011         int port = 0;
2012         int max_namelen = PAGE_SIZE;
2013         int max_pathlen = NFS_MAXPATHLEN;
2014         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2015
2016         if (nfs_parse_mount_options((char *)options, args) == 0)
2017                 return -EINVAL;
2018
2019         if (!nfs_verify_server_address(sap))
2020                 goto out_no_address;
2021
2022         if (args->version == 4) {
2023 #if IS_ENABLED(CONFIG_NFS_V4)
2024                 port = NFS_PORT;
2025                 max_namelen = NFS4_MAXNAMLEN;
2026                 max_pathlen = NFS4_MAXPATHLEN;
2027                 nfs_validate_transport_protocol(args);
2028                 nfs4_validate_mount_flags(args);
2029 #else
2030                 goto out_v4_not_compiled;
2031 #endif /* CONFIG_NFS_V4 */
2032         } else
2033                 nfs_set_mount_transport_protocol(args);
2034
2035         nfs_set_port(sap, &args->nfs_server.port, port);
2036
2037         if (args->auth_flavor_len > 1)
2038                 goto out_bad_auth;
2039
2040         return nfs_parse_devname(dev_name,
2041                                    &args->nfs_server.hostname,
2042                                    max_namelen,
2043                                    &args->nfs_server.export_path,
2044                                    max_pathlen);
2045
2046 #if !IS_ENABLED(CONFIG_NFS_V4)
2047 out_v4_not_compiled:
2048         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2049         return -EPROTONOSUPPORT;
2050 #endif /* !CONFIG_NFS_V4 */
2051
2052 out_no_address:
2053         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2054         return -EINVAL;
2055
2056 out_bad_auth:
2057         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2058         return -EINVAL;
2059 }
2060
2061 static int
2062 nfs_compare_remount_data(struct nfs_server *nfss,
2063                          struct nfs_parsed_mount_data *data)
2064 {
2065         if (data->flags != nfss->flags ||
2066             data->rsize != nfss->rsize ||
2067             data->wsize != nfss->wsize ||
2068             data->retrans != nfss->client->cl_timeout->to_retries ||
2069             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2070             data->acregmin != nfss->acregmin / HZ ||
2071             data->acregmax != nfss->acregmax / HZ ||
2072             data->acdirmin != nfss->acdirmin / HZ ||
2073             data->acdirmax != nfss->acdirmax / HZ ||
2074             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2075             data->nfs_server.port != nfss->port ||
2076             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2077             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2078                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2079                 return -EINVAL;
2080
2081         return 0;
2082 }
2083
2084 int
2085 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2086 {
2087         int error;
2088         struct nfs_server *nfss = sb->s_fs_info;
2089         struct nfs_parsed_mount_data *data;
2090         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2091         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2092         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2093
2094         /*
2095          * Userspace mount programs that send binary options generally send
2096          * them populated with default values. We have no way to know which
2097          * ones were explicitly specified. Fall back to legacy behavior and
2098          * just return success.
2099          */
2100         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2101             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2102                                            options->version <= 6))))
2103                 return 0;
2104
2105         data = kzalloc(sizeof(*data), GFP_KERNEL);
2106         if (data == NULL)
2107                 return -ENOMEM;
2108
2109         /* fill out struct with values from existing mount */
2110         data->flags = nfss->flags;
2111         data->rsize = nfss->rsize;
2112         data->wsize = nfss->wsize;
2113         data->retrans = nfss->client->cl_timeout->to_retries;
2114         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2115         data->acregmin = nfss->acregmin / HZ;
2116         data->acregmax = nfss->acregmax / HZ;
2117         data->acdirmin = nfss->acdirmin / HZ;
2118         data->acdirmax = nfss->acdirmax / HZ;
2119         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2120         data->nfs_server.port = nfss->port;
2121         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2122         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2123                 data->nfs_server.addrlen);
2124
2125         /* overwrite those values with any that were specified */
2126         error = nfs_parse_mount_options((char *)options, data);
2127         if (error < 0)
2128                 goto out;
2129
2130         /*
2131          * noac is a special case. It implies -o sync, but that's not
2132          * necessarily reflected in the mtab options. do_remount_sb
2133          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2134          * remount options, so we have to explicitly reset it.
2135          */
2136         if (data->flags & NFS_MOUNT_NOAC)
2137                 *flags |= MS_SYNCHRONOUS;
2138
2139         /* compare new mount options with old ones */
2140         error = nfs_compare_remount_data(nfss, data);
2141 out:
2142         kfree(data);
2143         return error;
2144 }
2145 EXPORT_SYMBOL_GPL(nfs_remount);
2146
2147 /*
2148  * Initialise the common bits of the superblock
2149  */
2150 inline void nfs_initialise_sb(struct super_block *sb)
2151 {
2152         struct nfs_server *server = NFS_SB(sb);
2153
2154         sb->s_magic = NFS_SUPER_MAGIC;
2155
2156         /* We probably want something more informative here */
2157         snprintf(sb->s_id, sizeof(sb->s_id),
2158                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2159
2160         if (sb->s_blocksize == 0)
2161                 sb->s_blocksize = nfs_block_bits(server->wsize,
2162                                                  &sb->s_blocksize_bits);
2163
2164         sb->s_bdi = &server->backing_dev_info;
2165
2166         nfs_super_set_maxbytes(sb, server->maxfilesize);
2167 }
2168
2169 /*
2170  * Finish setting up an NFS2/3 superblock
2171  */
2172 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2173 {
2174         struct nfs_parsed_mount_data *data = mount_info->parsed;
2175         struct nfs_server *server = NFS_SB(sb);
2176
2177         sb->s_blocksize_bits = 0;
2178         sb->s_blocksize = 0;
2179         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2180         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2181         if (data && data->bsize)
2182                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2183
2184         if (server->nfs_client->rpc_ops->version != 2) {
2185                 /* The VFS shouldn't apply the umask to mode bits. We will do
2186                  * so ourselves when necessary.
2187                  */
2188                 sb->s_flags |= MS_POSIXACL;
2189                 sb->s_time_gran = 1;
2190         }
2191
2192         nfs_initialise_sb(sb);
2193 }
2194 EXPORT_SYMBOL_GPL(nfs_fill_super);
2195
2196 /*
2197  * Finish setting up a cloned NFS2/3/4 superblock
2198  */
2199 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2200 {
2201         const struct super_block *old_sb = mount_info->cloned->sb;
2202         struct nfs_server *server = NFS_SB(sb);
2203
2204         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2205         sb->s_blocksize = old_sb->s_blocksize;
2206         sb->s_maxbytes = old_sb->s_maxbytes;
2207         sb->s_xattr = old_sb->s_xattr;
2208         sb->s_op = old_sb->s_op;
2209         sb->s_time_gran = 1;
2210
2211         if (server->nfs_client->rpc_ops->version != 2) {
2212                 /* The VFS shouldn't apply the umask to mode bits. We will do
2213                  * so ourselves when necessary.
2214                  */
2215                 sb->s_flags |= MS_POSIXACL;
2216         }
2217
2218         nfs_initialise_sb(sb);
2219 }
2220
2221 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2222 {
2223         const struct nfs_server *a = s->s_fs_info;
2224         const struct rpc_clnt *clnt_a = a->client;
2225         const struct rpc_clnt *clnt_b = b->client;
2226
2227         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2228                 goto Ebusy;
2229         if (a->nfs_client != b->nfs_client)
2230                 goto Ebusy;
2231         if (a->flags != b->flags)
2232                 goto Ebusy;
2233         if (a->wsize != b->wsize)
2234                 goto Ebusy;
2235         if (a->rsize != b->rsize)
2236                 goto Ebusy;
2237         if (a->acregmin != b->acregmin)
2238                 goto Ebusy;
2239         if (a->acregmax != b->acregmax)
2240                 goto Ebusy;
2241         if (a->acdirmin != b->acdirmin)
2242                 goto Ebusy;
2243         if (a->acdirmax != b->acdirmax)
2244                 goto Ebusy;
2245         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2246                 goto Ebusy;
2247         return 1;
2248 Ebusy:
2249         return 0;
2250 }
2251
2252 struct nfs_sb_mountdata {
2253         struct nfs_server *server;
2254         int mntflags;
2255 };
2256
2257 static int nfs_set_super(struct super_block *s, void *data)
2258 {
2259         struct nfs_sb_mountdata *sb_mntdata = data;
2260         struct nfs_server *server = sb_mntdata->server;
2261         int ret;
2262
2263         s->s_flags = sb_mntdata->mntflags;
2264         s->s_fs_info = server;
2265         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2266         ret = set_anon_super(s, server);
2267         if (ret == 0)
2268                 server->s_dev = s->s_dev;
2269         return ret;
2270 }
2271
2272 static int nfs_compare_super_address(struct nfs_server *server1,
2273                                      struct nfs_server *server2)
2274 {
2275         struct sockaddr *sap1, *sap2;
2276
2277         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2278         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2279
2280         if (sap1->sa_family != sap2->sa_family)
2281                 return 0;
2282
2283         switch (sap1->sa_family) {
2284         case AF_INET: {
2285                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2286                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2287                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2288                         return 0;
2289                 if (sin1->sin_port != sin2->sin_port)
2290                         return 0;
2291                 break;
2292         }
2293         case AF_INET6: {
2294                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2295                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2296                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2297                         return 0;
2298                 if (sin1->sin6_port != sin2->sin6_port)
2299                         return 0;
2300                 break;
2301         }
2302         default:
2303                 return 0;
2304         }
2305
2306         return 1;
2307 }
2308
2309 static int nfs_compare_super(struct super_block *sb, void *data)
2310 {
2311         struct nfs_sb_mountdata *sb_mntdata = data;
2312         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2313         int mntflags = sb_mntdata->mntflags;
2314
2315         if (!nfs_compare_super_address(old, server))
2316                 return 0;
2317         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2318         if (old->flags & NFS_MOUNT_UNSHARED)
2319                 return 0;
2320         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2321                 return 0;
2322         return nfs_compare_mount_options(sb, server, mntflags);
2323 }
2324
2325 #ifdef CONFIG_NFS_FSCACHE
2326 static void nfs_get_cache_cookie(struct super_block *sb,
2327                                  struct nfs_parsed_mount_data *parsed,
2328                                  struct nfs_clone_mount *cloned)
2329 {
2330         struct nfs_server *nfss = NFS_SB(sb);
2331         char *uniq = NULL;
2332         int ulen = 0;
2333
2334         nfss->fscache_key = NULL;
2335         nfss->fscache = NULL;
2336
2337         if (parsed) {
2338                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2339                         return;
2340                 if (parsed->fscache_uniq) {
2341                         uniq = parsed->fscache_uniq;
2342                         ulen = strlen(parsed->fscache_uniq);
2343                 }
2344         } else if (cloned) {
2345                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2346                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2347                         return;
2348                 if (mnt_s->fscache_key) {
2349                         uniq = mnt_s->fscache_key->key.uniquifier;
2350                         ulen = mnt_s->fscache_key->key.uniq_len;
2351                 };
2352         } else
2353                 return;
2354
2355         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2356 }
2357 #else
2358 static void nfs_get_cache_cookie(struct super_block *sb,
2359                                  struct nfs_parsed_mount_data *parsed,
2360                                  struct nfs_clone_mount *cloned)
2361 {
2362 }
2363 #endif
2364
2365 static int nfs_bdi_register(struct nfs_server *server)
2366 {
2367         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2368 }
2369
2370 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2371                         struct nfs_mount_info *mount_info)
2372 {
2373         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2374 }
2375 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2376
2377 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2378                           struct nfs_mount_info *mount_info)
2379 {
2380         /* clone any lsm security options from the parent to the new sb */
2381         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2382         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2383                 return -ESTALE;
2384         return 0;
2385 }
2386 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2387
2388 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2389                                    int flags, const char *dev_name,
2390                                    struct nfs_mount_info *mount_info,
2391                                    struct nfs_subversion *nfs_mod)
2392 {
2393         struct super_block *s;
2394         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2395         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2396         struct nfs_sb_mountdata sb_mntdata = {
2397                 .mntflags = flags,
2398                 .server = server,
2399         };
2400         int error;
2401
2402         if (server->flags & NFS_MOUNT_UNSHARED)
2403                 compare_super = NULL;
2404
2405         /* -o noac implies -o sync */
2406         if (server->flags & NFS_MOUNT_NOAC)
2407                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2408
2409         /* Get a superblock - note that we may end up sharing one that already exists */
2410         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2411         if (IS_ERR(s)) {
2412                 mntroot = ERR_CAST(s);
2413                 goto out_err_nosb;
2414         }
2415
2416         if (s->s_fs_info != server) {
2417                 nfs_free_server(server);
2418                 server = NULL;
2419         } else {
2420                 error = nfs_bdi_register(server);
2421                 if (error) {
2422                         mntroot = ERR_PTR(error);
2423                         goto error_splat_bdi;
2424                 }
2425         }
2426
2427         if (!s->s_root) {
2428                 /* initial superblock/root creation */
2429                 mount_info->fill_super(s, mount_info);
2430                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2431         }
2432
2433         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2434         if (IS_ERR(mntroot))
2435                 goto error_splat_super;
2436
2437         error = mount_info->set_security(s, mntroot, mount_info);
2438         if (error)
2439                 goto error_splat_root;
2440
2441         s->s_flags |= MS_ACTIVE;
2442
2443 out:
2444         return mntroot;
2445
2446 out_err_nosb:
2447         nfs_free_server(server);
2448         goto out;
2449
2450 error_splat_root:
2451         dput(mntroot);
2452         mntroot = ERR_PTR(error);
2453 error_splat_super:
2454         if (server && !s->s_root)
2455                 bdi_unregister(&server->backing_dev_info);
2456 error_splat_bdi:
2457         deactivate_locked_super(s);
2458         goto out;
2459 }
2460 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2461
2462 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2463         int flags, const char *dev_name, void *raw_data)
2464 {
2465         struct nfs_mount_info mount_info = {
2466                 .fill_super = nfs_fill_super,
2467                 .set_security = nfs_set_sb_security,
2468         };
2469         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2470         struct nfs_subversion *nfs_mod;
2471         int error;
2472
2473         mount_info.parsed = nfs_alloc_parsed_mount_data();
2474         mount_info.mntfh = nfs_alloc_fhandle();
2475         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2476                 goto out;
2477
2478         /* Validate the mount data */
2479         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2480         if (error == NFS_TEXT_DATA)
2481                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2482         if (error < 0) {
2483                 mntroot = ERR_PTR(error);
2484                 goto out;
2485         }
2486
2487         nfs_mod = get_nfs_version(mount_info.parsed->version);
2488         if (IS_ERR(nfs_mod)) {
2489                 mntroot = ERR_CAST(nfs_mod);
2490                 goto out;
2491         }
2492
2493         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2494
2495         put_nfs_version(nfs_mod);
2496 out:
2497         nfs_free_parsed_mount_data(mount_info.parsed);
2498         nfs_free_fhandle(mount_info.mntfh);
2499         return mntroot;
2500 }
2501 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2502
2503 /*
2504  * Ensure that we unregister the bdi before kill_anon_super
2505  * releases the device name
2506  */
2507 void nfs_put_super(struct super_block *s)
2508 {
2509         struct nfs_server *server = NFS_SB(s);
2510
2511         bdi_unregister(&server->backing_dev_info);
2512 }
2513 EXPORT_SYMBOL_GPL(nfs_put_super);
2514
2515 /*
2516  * Destroy an NFS2/3 superblock
2517  */
2518 void nfs_kill_super(struct super_block *s)
2519 {
2520         struct nfs_server *server = NFS_SB(s);
2521
2522         kill_anon_super(s);
2523         nfs_fscache_release_super_cookie(s);
2524         nfs_free_server(server);
2525 }
2526 EXPORT_SYMBOL_GPL(nfs_kill_super);
2527
2528 /*
2529  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2530  */
2531 static struct dentry *
2532 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2533                 const char *dev_name, void *raw_data)
2534 {
2535         struct nfs_clone_mount *data = raw_data;
2536         struct nfs_mount_info mount_info = {
2537                 .fill_super = nfs_clone_super,
2538                 .set_security = nfs_clone_sb_security,
2539                 .cloned = data,
2540         };
2541         struct nfs_server *server;
2542         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2543         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2544
2545         dprintk("--> nfs_xdev_mount()\n");
2546
2547         mount_info.mntfh = mount_info.cloned->fh;
2548
2549         /* create a new volume representation */
2550         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2551
2552         if (IS_ERR(server))
2553                 mntroot = ERR_CAST(server);
2554         else
2555                 mntroot = nfs_fs_mount_common(server, flags,
2556                                 dev_name, &mount_info, nfs_mod);
2557
2558         dprintk("<-- nfs_xdev_mount() = %ld\n",
2559                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2560         return mntroot;
2561 }
2562
2563 #if IS_ENABLED(CONFIG_NFS_V4)
2564
2565 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2566 {
2567         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2568                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2569 }
2570
2571 /*
2572  * Validate NFSv4 mount options
2573  */
2574 static int nfs4_validate_mount_data(void *options,
2575                                     struct nfs_parsed_mount_data *args,
2576                                     const char *dev_name)
2577 {
2578         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2579         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2580         char *c;
2581
2582         if (data == NULL)
2583                 goto out_no_data;
2584
2585         args->version = 4;
2586
2587         switch (data->version) {
2588         case 1:
2589                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2590                         goto out_no_address;
2591                 if (data->host_addrlen == 0)
2592                         goto out_no_address;
2593                 args->nfs_server.addrlen = data->host_addrlen;
2594                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2595                         return -EFAULT;
2596                 if (!nfs_verify_server_address(sap))
2597                         goto out_no_address;
2598                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2599
2600                 if (data->auth_flavourlen) {
2601                         if (data->auth_flavourlen > 1)
2602                                 goto out_inval_auth;
2603                         if (copy_from_user(&args->auth_flavors[0],
2604                                            data->auth_flavours,
2605                                            sizeof(args->auth_flavors[0])))
2606                                 return -EFAULT;
2607                 }
2608
2609                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2610                 if (IS_ERR(c))
2611                         return PTR_ERR(c);
2612                 args->nfs_server.hostname = c;
2613
2614                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2615                 if (IS_ERR(c))
2616                         return PTR_ERR(c);
2617                 args->nfs_server.export_path = c;
2618                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2619
2620                 c = strndup_user(data->client_addr.data, 16);
2621                 if (IS_ERR(c))
2622                         return PTR_ERR(c);
2623                 args->client_address = c;
2624
2625                 /*
2626                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2627                  * can deal with.
2628                  */
2629
2630                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2631                 args->rsize     = data->rsize;
2632                 args->wsize     = data->wsize;
2633                 args->timeo     = data->timeo;
2634                 args->retrans   = data->retrans;
2635                 args->acregmin  = data->acregmin;
2636                 args->acregmax  = data->acregmax;
2637                 args->acdirmin  = data->acdirmin;
2638                 args->acdirmax  = data->acdirmax;
2639                 args->nfs_server.protocol = data->proto;
2640                 nfs_validate_transport_protocol(args);
2641
2642                 break;
2643         default:
2644                 return NFS_TEXT_DATA;
2645         }
2646
2647         return 0;
2648
2649 out_no_data:
2650         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2651         return -EINVAL;
2652
2653 out_inval_auth:
2654         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2655                  data->auth_flavourlen);
2656         return -EINVAL;
2657
2658 out_no_address:
2659         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2660         return -EINVAL;
2661 }
2662
2663 /*
2664  * NFS v4 module parameters need to stay in the
2665  * NFS client for backwards compatibility
2666  */
2667 unsigned int nfs_callback_set_tcpport;
2668 unsigned short nfs_callback_tcpport;
2669 /* Default cache timeout is 10 minutes */
2670 unsigned int nfs_idmap_cache_timeout = 600;
2671 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2672 bool nfs4_disable_idmapping = true;
2673 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2674 unsigned short send_implementation_id = 1;
2675 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2676
2677 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2678 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2679 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2680 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2681 EXPORT_SYMBOL_GPL(max_session_slots);
2682 EXPORT_SYMBOL_GPL(send_implementation_id);
2683 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2684
2685 #define NFS_CALLBACK_MAXPORTNR (65535U)
2686
2687 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2688 {
2689         unsigned long num;
2690         int ret;
2691
2692         if (!val)
2693                 return -EINVAL;
2694         ret = kstrtoul(val, 0, &num);
2695         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2696                 return -EINVAL;
2697         *((unsigned int *)kp->arg) = num;
2698         return 0;
2699 }
2700 static struct kernel_param_ops param_ops_portnr = {
2701         .set = param_set_portnr,
2702         .get = param_get_uint,
2703 };
2704 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2705
2706 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2707 module_param(nfs_idmap_cache_timeout, int, 0644);
2708 module_param(nfs4_disable_idmapping, bool, 0644);
2709 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2710                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2711 MODULE_PARM_DESC(nfs4_disable_idmapping,
2712                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2713 module_param(max_session_slots, ushort, 0644);
2714 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2715                 "requests the client will negotiate");
2716 module_param(send_implementation_id, ushort, 0644);
2717 MODULE_PARM_DESC(send_implementation_id,
2718                 "Send implementation ID with NFSv4.1 exchange_id");
2719 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2720 MODULE_ALIAS("nfs4");
2721
2722 #endif /* CONFIG_NFS_V4 */