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, Opt_vers_4_2,
 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         { Opt_vers_4_2, "4.2" },
 284
 285         { Opt_vers_err, NULL }
 286 };
 287
 288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 289                 int flags, const char *dev_name, void *raw_data);
 290
 291 struct file_system_type nfs_fs_type = {
 292         .owner          = THIS_MODULE,
 293         .name           = "nfs",
 294         .mount          = nfs_fs_mount,
 295         .kill_sb        = nfs_kill_super,
 296         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 297 };
 298 MODULE_ALIAS_FS("nfs");
 299 EXPORT_SYMBOL_GPL(nfs_fs_type);
 300
 301 struct file_system_type nfs_xdev_fs_type = {
 302         .owner          = THIS_MODULE,
 303         .name           = "nfs",
 304         .mount          = nfs_xdev_mount,
 305         .kill_sb        = nfs_kill_super,
 306         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 307 };
 308
 309 const struct super_operations nfs_sops = {
 310         .alloc_inode    = nfs_alloc_inode,
 311         .destroy_inode  = nfs_destroy_inode,
 312         .write_inode    = nfs_write_inode,
 313         .drop_inode     = nfs_drop_inode,
 314         .put_super      = nfs_put_super,
 315         .statfs         = nfs_statfs,
 316         .evict_inode    = nfs_evict_inode,
 317         .umount_begin   = nfs_umount_begin,
 318         .show_options   = nfs_show_options,
 319         .show_devname   = nfs_show_devname,
 320         .show_path      = nfs_show_path,
 321         .show_stats     = nfs_show_stats,
 322         .remount_fs     = nfs_remount,
 323 };
 324 EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326 #if IS_ENABLED(CONFIG_NFS_V4)
 327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328 static int nfs4_validate_mount_data(void *options,
 329         struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331 struct file_system_type nfs4_fs_type = {
 332         .owner          = THIS_MODULE,
 333         .name           = "nfs4",
 334         .mount          = nfs_fs_mount,
 335         .kill_sb        = nfs_kill_super,
 336         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337 };
 338 MODULE_ALIAS_FS("nfs4");
 339 MODULE_ALIAS("nfs4");
 340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342 static int __init register_nfs4_fs(void)
 343 {
 344         return register_filesystem(&nfs4_fs_type);
 345 }
 346
 347 static void unregister_nfs4_fs(void)
 348 {
 349         unregister_filesystem(&nfs4_fs_type);
 350 }
 351 #else
 352 static int __init register_nfs4_fs(void)
 353 {
 354         return 0;
 355 }
 356
 357 static void unregister_nfs4_fs(void)
 358 {
 359 }
 360 #endif
 361
 362 static struct shrinker acl_shrinker = {
 363         .count_objects  = nfs_access_cache_count,
 364         .scan_objects   = nfs_access_cache_scan,
 365         .seeks          = DEFAULT_SEEKS,
 366 };
 367
 368 /*
 369  * Register the NFS filesystems
 370  */
 371 int __init register_nfs_fs(void)
 372 {
 373         int ret;
 374
 375         ret = register_filesystem(&nfs_fs_type);
 376         if (ret < 0)
 377                 goto error_0;
 378
 379         ret = register_nfs4_fs();
 380         if (ret < 0)
 381                 goto error_1;
 382
 383         ret = nfs_register_sysctl();
 384         if (ret < 0)
 385                 goto error_2;
 386         register_shrinker(&acl_shrinker);
 387         return 0;
 388
 389 error_2:
 390         unregister_nfs4_fs();
 391 error_1:
 392         unregister_filesystem(&nfs_fs_type);
 393 error_0:
 394         return ret;
 395 }
 396
 397 /*
 398  * Unregister the NFS filesystems
 399  */
 400 void __exit unregister_nfs_fs(void)
 401 {
 402         unregister_shrinker(&acl_shrinker);
 403         nfs_unregister_sysctl();
 404         unregister_nfs4_fs();
 405         unregister_filesystem(&nfs_fs_type);
 406 }
 407
 408 void nfs_sb_active(struct super_block *sb)
 409 {
 410         struct nfs_server *server = NFS_SB(sb);
 411
 412         if (atomic_inc_return(&server->active) == 1)
 413                 atomic_inc(&sb->s_active);
 414 }
 415 EXPORT_SYMBOL_GPL(nfs_sb_active);
 416
 417 void nfs_sb_deactive(struct super_block *sb)
 418 {
 419         struct nfs_server *server = NFS_SB(sb);
 420
 421         if (atomic_dec_and_test(&server->active))
 422                 deactivate_super(sb);
 423 }
 424 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 425
 426 /*
 427  * Deliver file system statistics to userspace
 428  */
 429 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 430 {
 431         struct nfs_server *server = NFS_SB(dentry->d_sb);
 432         unsigned char blockbits;
 433         unsigned long blockres;
 434         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 435         struct nfs_fsstat res;
 436         int error = -ENOMEM;
 437
 438         res.fattr = nfs_alloc_fattr();
 439         if (res.fattr == NULL)
 440                 goto out_err;
 441
 442         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 443         if (unlikely(error == -ESTALE)) {
 444                 struct dentry *pd_dentry;
 445
 446                 pd_dentry = dget_parent(dentry);
 447                 if (pd_dentry != NULL) {
 448                         nfs_zap_caches(pd_dentry->d_inode);
 449                         dput(pd_dentry);
 450                 }
 451         }
 452         nfs_free_fattr(res.fattr);
 453         if (error < 0)
 454                 goto out_err;
 455
 456         buf->f_type = NFS_SUPER_MAGIC;
 457
 458         /*
 459          * Current versions of glibc do not correctly handle the
 460          * case where f_frsize != f_bsize.  Eventually we want to
 461          * report the value of wtmult in this field.
 462          */
 463         buf->f_frsize = dentry->d_sb->s_blocksize;
 464
 465         /*
 466          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 467          * are reported in units of f_frsize.  Linux hasn't had
 468          * an f_frsize field in its statfs struct until recently,
 469          * thus historically Linux's sys_statfs reports these
 470          * fields in units of f_bsize.
 471          */
 472         buf->f_bsize = dentry->d_sb->s_blocksize;
 473         blockbits = dentry->d_sb->s_blocksize_bits;
 474         blockres = (1 << blockbits) - 1;
 475         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 476         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 477         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 478
 479         buf->f_files = res.tfiles;
 480         buf->f_ffree = res.afiles;
 481
 482         buf->f_namelen = server->namelen;
 483
 484         return 0;
 485
 486  out_err:
 487         dprintk("%s: statfs error = %d\n", __func__, -error);
 488         return error;
 489 }
 490 EXPORT_SYMBOL_GPL(nfs_statfs);
 491
 492 /*
 493  * Map the security flavour number to a name
 494  */
 495 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 496 {
 497         static const struct {
 498                 rpc_authflavor_t flavour;
 499                 const char *str;
 500         } sec_flavours[] = {
 501                 { RPC_AUTH_NULL, "null" },
 502                 { RPC_AUTH_UNIX, "sys" },
 503                 { RPC_AUTH_GSS_KRB5, "krb5" },
 504                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 505                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 506                 { RPC_AUTH_GSS_LKEY, "lkey" },
 507                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 508                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 509                 { RPC_AUTH_GSS_SPKM, "spkm" },
 510                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 511                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 512                 { UINT_MAX, "unknown" }
 513         };
 514         int i;
 515
 516         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 517                 if (sec_flavours[i].flavour == flavour)
 518                         break;
 519         }
 520         return sec_flavours[i].str;
 521 }
 522
 523 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 524                                   int showdefaults)
 525 {
 526         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 527
 528         seq_printf(m, ",mountproto=");
 529         switch (sap->sa_family) {
 530         case AF_INET:
 531                 switch (nfss->mountd_protocol) {
 532                 case IPPROTO_UDP:
 533                         seq_printf(m, RPCBIND_NETID_UDP);
 534                         break;
 535                 case IPPROTO_TCP:
 536                         seq_printf(m, RPCBIND_NETID_TCP);
 537                         break;
 538                 default:
 539                         if (showdefaults)
 540                                 seq_printf(m, "auto");
 541                 }
 542                 break;
 543         case AF_INET6:
 544                 switch (nfss->mountd_protocol) {
 545                 case IPPROTO_UDP:
 546                         seq_printf(m, RPCBIND_NETID_UDP6);
 547                         break;
 548                 case IPPROTO_TCP:
 549                         seq_printf(m, RPCBIND_NETID_TCP6);
 550                         break;
 551                 default:
 552                         if (showdefaults)
 553                                 seq_printf(m, "auto");
 554                 }
 555                 break;
 556         default:
 557                 if (showdefaults)
 558                         seq_printf(m, "auto");
 559         }
 560 }
 561
 562 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 563                                     int showdefaults)
 564 {
 565         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 566
 567         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 568                 return;
 569
 570         switch (sap->sa_family) {
 571         case AF_INET: {
 572                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 573                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 574                 break;
 575         }
 576         case AF_INET6: {
 577                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 578                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 579                 break;
 580         }
 581         default:
 582                 if (showdefaults)
 583                         seq_printf(m, ",mountaddr=unspecified");
 584         }
 585
 586         if (nfss->mountd_version || showdefaults)
 587                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 588         if ((nfss->mountd_port &&
 589                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 590                 showdefaults)
 591                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 592
 593         nfs_show_mountd_netid(m, nfss, showdefaults);
 594 }
 595
 596 #if IS_ENABLED(CONFIG_NFS_V4)
 597 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 598                                     int showdefaults)
 599 {
 600         struct nfs_client *clp = nfss->nfs_client;
 601
 602         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 603 }
 604 #else
 605 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 606                                     int showdefaults)
 607 {
 608 }
 609 #endif
 610
 611 static void nfs_show_nfs_version(struct seq_file *m,
 612                 unsigned int version,
 613                 unsigned int minorversion)
 614 {
 615         seq_printf(m, ",vers=%u", version);
 616         if (version == 4)
 617                 seq_printf(m, ".%u", minorversion);
 618 }
 619
 620 /*
 621  * Describe the mount options in force on this server representation
 622  */
 623 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 624                                    int showdefaults)
 625 {
 626         static const struct proc_nfs_info {
 627                 int flag;
 628                 const char *str;
 629                 const char *nostr;
 630         } nfs_info[] = {
 631                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 632                 { NFS_MOUNT_POSIX, ",posix", "" },
 633                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 634                 { NFS_MOUNT_NOAC, ",noac", "" },
 635                 { NFS_MOUNT_NONLM, ",nolock", "" },
 636                 { NFS_MOUNT_NOACL, ",noacl", "" },
 637                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 638                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 639                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 640                 { 0, NULL, NULL }
 641         };
 642         const struct proc_nfs_info *nfs_infop;
 643         struct nfs_client *clp = nfss->nfs_client;
 644         u32 version = clp->rpc_ops->version;
 645         int local_flock, local_fcntl;
 646
 647         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 648         seq_printf(m, ",rsize=%u", nfss->rsize);
 649         seq_printf(m, ",wsize=%u", nfss->wsize);
 650         if (nfss->bsize != 0)
 651                 seq_printf(m, ",bsize=%u", nfss->bsize);
 652         seq_printf(m, ",namlen=%u", nfss->namelen);
 653         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 654                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 655         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 656                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 657         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 658                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 659         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 660                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 661         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 662                 if (nfss->flags & nfs_infop->flag)
 663                         seq_puts(m, nfs_infop->str);
 664                 else
 665                         seq_puts(m, nfs_infop->nostr);
 666         }
 667         rcu_read_lock();
 668         seq_printf(m, ",proto=%s",
 669                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 670         rcu_read_unlock();
 671         if (version == 4) {
 672                 if (nfss->port != NFS_PORT)
 673                         seq_printf(m, ",port=%u", nfss->port);
 674         } else
 675                 if (nfss->port)
 676                         seq_printf(m, ",port=%u", nfss->port);
 677
 678         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 679         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 680         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 681
 682         if (version != 4)
 683                 nfs_show_mountd_options(m, nfss, showdefaults);
 684         else
 685                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 686
 687         if (nfss->options & NFS_OPTION_FSCACHE)
 688                 seq_printf(m, ",fsc");
 689
 690         if (nfss->options & NFS_OPTION_MIGRATION)
 691                 seq_printf(m, ",migration");
 692
 693         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 694                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 695                         seq_printf(m, ",lookupcache=none");
 696                 else
 697                         seq_printf(m, ",lookupcache=pos");
 698         }
 699
 700         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 701         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 702
 703         if (!local_flock && !local_fcntl)
 704                 seq_printf(m, ",local_lock=none");
 705         else if (local_flock && local_fcntl)
 706                 seq_printf(m, ",local_lock=all");
 707         else if (local_flock)
 708                 seq_printf(m, ",local_lock=flock");
 709         else
 710                 seq_printf(m, ",local_lock=posix");
 711 }
 712
 713 /*
 714  * Describe the mount options on this VFS mountpoint
 715  */
 716 int nfs_show_options(struct seq_file *m, struct dentry *root)
 717 {
 718         struct nfs_server *nfss = NFS_SB(root->d_sb);
 719
 720         nfs_show_mount_options(m, nfss, 0);
 721
 722         rcu_read_lock();
 723         seq_printf(m, ",addr=%s",
 724                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 725                                                         RPC_DISPLAY_ADDR));
 726         rcu_read_unlock();
 727
 728         return 0;
 729 }
 730 EXPORT_SYMBOL_GPL(nfs_show_options);
 731
 732 #if IS_ENABLED(CONFIG_NFS_V4)
 733 #ifdef CONFIG_NFS_V4_1
 734 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 735 {
 736         if (nfs4_has_session(server->nfs_client))
 737                 seq_printf(m, ",sessions");
 738 }
 739 #else
 740 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 741 #endif
 742 #endif
 743
 744 #ifdef CONFIG_NFS_V4_1
 745 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 746 {
 747         seq_printf(m, ",pnfs=");
 748         if (server->pnfs_curr_ld)
 749                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 750         else
 751                 seq_printf(m, "not configured");
 752 }
 753
 754 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 755 {
 756         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 757                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 758                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 759                            "date='%llu,%u'",
 760                            impl_id->name, impl_id->domain,
 761                            impl_id->date.seconds, impl_id->date.nseconds);
 762         }
 763 }
 764 #else
 765 #if IS_ENABLED(CONFIG_NFS_V4)
 766 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 767 {
 768 }
 769 #endif
 770 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 771 {
 772 }
 773 #endif
 774
 775 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 776 {
 777         char *page = (char *) __get_free_page(GFP_KERNEL);
 778         char *devname, *dummy;
 779         int err = 0;
 780         if (!page)
 781                 return -ENOMEM;
 782         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 783         if (IS_ERR(devname))
 784                 err = PTR_ERR(devname);
 785         else
 786                 seq_escape(m, devname, " \t\n\\");
 787         free_page((unsigned long)page);
 788         return err;
 789 }
 790 EXPORT_SYMBOL_GPL(nfs_show_devname);
 791
 792 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 793 {
 794         seq_puts(m, "/");
 795         return 0;
 796 }
 797 EXPORT_SYMBOL_GPL(nfs_show_path);
 798
 799 /*
 800  * Present statistical information for this VFS mountpoint
 801  */
 802 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 803 {
 804         int i, cpu;
 805         struct nfs_server *nfss = NFS_SB(root->d_sb);
 806         struct rpc_auth *auth = nfss->client->cl_auth;
 807         struct nfs_iostats totals = { };
 808
 809         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 810
 811         /*
 812          * Display all mount option settings
 813          */
 814         seq_printf(m, "\n\topts:\t");
 815         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 816         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 817         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 818         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 819         nfs_show_mount_options(m, nfss, 1);
 820
 821         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 822
 823         show_implementation_id(m, nfss);
 824
 825         seq_printf(m, "\n\tcaps:\t");
 826         seq_printf(m, "caps=0x%x", nfss->caps);
 827         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 828         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 829         seq_printf(m, ",bsize=%u", nfss->bsize);
 830         seq_printf(m, ",namlen=%u", nfss->namelen);
 831
 832 #if IS_ENABLED(CONFIG_NFS_V4)
 833         if (nfss->nfs_client->rpc_ops->version == 4) {
 834                 seq_printf(m, "\n\tnfsv4:\t");
 835                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 836                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 837                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 838                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 839                 show_sessions(m, nfss);
 840                 show_pnfs(m, nfss);
 841         }
 842 #endif
 843
 844         /*
 845          * Display security flavor in effect for this mount
 846          */
 847         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 848         if (auth->au_flavor)
 849                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 850
 851         /*
 852          * Display superblock I/O counters
 853          */
 854         for_each_possible_cpu(cpu) {
 855                 struct nfs_iostats *stats;
 856
 857                 preempt_disable();
 858                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 859
 860                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 861                         totals.events[i] += stats->events[i];
 862                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 863                         totals.bytes[i] += stats->bytes[i];
 864 #ifdef CONFIG_NFS_FSCACHE
 865                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 866                         totals.fscache[i] += stats->fscache[i];
 867 #endif
 868
 869                 preempt_enable();
 870         }
 871
 872         seq_printf(m, "\n\tevents:\t");
 873         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 874                 seq_printf(m, "%lu ", totals.events[i]);
 875         seq_printf(m, "\n\tbytes:\t");
 876         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 877                 seq_printf(m, "%Lu ", totals.bytes[i]);
 878 #ifdef CONFIG_NFS_FSCACHE
 879         if (nfss->options & NFS_OPTION_FSCACHE) {
 880                 seq_printf(m, "\n\tfsc:\t");
 881                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 882                         seq_printf(m, "%Lu ", totals.bytes[i]);
 883         }
 884 #endif
 885         seq_printf(m, "\n");
 886
 887         rpc_print_iostats(m, nfss->client);
 888
 889         return 0;
 890 }
 891 EXPORT_SYMBOL_GPL(nfs_show_stats);
 892
 893 /*
 894  * Begin unmount by attempting to remove all automounted mountpoints we added
 895  * in response to xdev traversals and referrals
 896  */
 897 void nfs_umount_begin(struct super_block *sb)
 898 {
 899         struct nfs_server *server;
 900         struct rpc_clnt *rpc;
 901
 902         server = NFS_SB(sb);
 903         /* -EIO all pending I/O */
 904         rpc = server->client_acl;
 905         if (!IS_ERR(rpc))
 906                 rpc_killall_tasks(rpc);
 907         rpc = server->client;
 908         if (!IS_ERR(rpc))
 909                 rpc_killall_tasks(rpc);
 910 }
 911 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 912
 913 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 914 {
 915         struct nfs_parsed_mount_data *data;
 916
 917         data = kzalloc(sizeof(*data), GFP_KERNEL);
 918         if (data) {
 919                 data->acregmin          = NFS_DEF_ACREGMIN;
 920                 data->acregmax          = NFS_DEF_ACREGMAX;
 921                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 922                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 923                 data->mount_server.port = NFS_UNSPEC_PORT;
 924                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 925                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 926                 data->auth_flavors[0]   = RPC_AUTH_MAXFLAVOR;
 927                 data->auth_flavor_len   = 0;
 928                 data->minorversion      = 0;
 929                 data->need_mount        = true;
 930                 data->net               = current->nsproxy->net_ns;
 931                 security_init_mnt_opts(&data->lsm_opts);
 932         }
 933         return data;
 934 }
 935
 936 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 937 {
 938         if (data) {
 939                 kfree(data->client_address);
 940                 kfree(data->mount_server.hostname);
 941                 kfree(data->nfs_server.export_path);
 942                 kfree(data->nfs_server.hostname);
 943                 kfree(data->fscache_uniq);
 944                 security_free_mnt_opts(&data->lsm_opts);
 945                 kfree(data);
 946         }
 947 }
 948
 949 /*
 950  * Sanity-check a server address provided by the mount command.
 951  *
 952  * Address family must be initialized, and address must not be
 953  * the ANY address for that family.
 954  */
 955 static int nfs_verify_server_address(struct sockaddr *addr)
 956 {
 957         switch (addr->sa_family) {
 958         case AF_INET: {
 959                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 960                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 961         }
 962         case AF_INET6: {
 963                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 964                 return !ipv6_addr_any(sa);
 965         }
 966         }
 967
 968         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 969         return 0;
 970 }
 971
 972 /*
 973  * Select between a default port value and a user-specified port value.
 974  * If a zero value is set, then autobind will be used.
 975  */
 976 static void nfs_set_port(struct sockaddr *sap, int *port,
 977                                  const unsigned short default_port)
 978 {
 979         if (*port == NFS_UNSPEC_PORT)
 980                 *port = default_port;
 981
 982         rpc_set_port(sap, *port);
 983 }
 984
 985 /*
 986  * Sanity check the NFS transport protocol.
 987  *
 988  */
 989 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 990 {
 991         switch (mnt->nfs_server.protocol) {
 992         case XPRT_TRANSPORT_UDP:
 993         case XPRT_TRANSPORT_TCP:
 994         case XPRT_TRANSPORT_RDMA:
 995                 break;
 996         default:
 997                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 998         }
 999 }
1000
1001 /*
1002  * For text based NFSv2/v3 mounts, the mount protocol transport default
1003  * settings should depend upon the specified NFS transport.
1004  */
1005 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1006 {
1007         nfs_validate_transport_protocol(mnt);
1008
1009         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1010             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1011                         return;
1012         switch (mnt->nfs_server.protocol) {
1013         case XPRT_TRANSPORT_UDP:
1014                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1015                 break;
1016         case XPRT_TRANSPORT_TCP:
1017         case XPRT_TRANSPORT_RDMA:
1018                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1019         }
1020 }
1021
1022 static void nfs_set_auth_parsed_mount_data(struct nfs_parsed_mount_data *data,
1023                 rpc_authflavor_t pseudoflavor)
1024 {
1025         data->auth_flavors[0] = pseudoflavor;
1026         data->auth_flavor_len = 1;
1027 }
1028
1029 /*
1030  * Parse the value of the 'sec=' option.
1031  */
1032 static int nfs_parse_security_flavors(char *value,
1033                                       struct nfs_parsed_mount_data *mnt)
1034 {
1035         substring_t args[MAX_OPT_ARGS];
1036         rpc_authflavor_t pseudoflavor;
1037
1038         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1039
1040         switch (match_token(value, nfs_secflavor_tokens, args)) {
1041         case Opt_sec_none:
1042                 pseudoflavor = RPC_AUTH_NULL;
1043                 break;
1044         case Opt_sec_sys:
1045                 pseudoflavor = RPC_AUTH_UNIX;
1046                 break;
1047         case Opt_sec_krb5:
1048                 pseudoflavor = RPC_AUTH_GSS_KRB5;
1049                 break;
1050         case Opt_sec_krb5i:
1051                 pseudoflavor = RPC_AUTH_GSS_KRB5I;
1052                 break;
1053         case Opt_sec_krb5p:
1054                 pseudoflavor = RPC_AUTH_GSS_KRB5P;
1055                 break;
1056         case Opt_sec_lkey:
1057                 pseudoflavor = RPC_AUTH_GSS_LKEY;
1058                 break;
1059         case Opt_sec_lkeyi:
1060                 pseudoflavor = RPC_AUTH_GSS_LKEYI;
1061                 break;
1062         case Opt_sec_lkeyp:
1063                 pseudoflavor = RPC_AUTH_GSS_LKEYP;
1064                 break;
1065         case Opt_sec_spkm:
1066                 pseudoflavor = RPC_AUTH_GSS_SPKM;
1067                 break;
1068         case Opt_sec_spkmi:
1069                 pseudoflavor = RPC_AUTH_GSS_SPKMI;
1070                 break;
1071         case Opt_sec_spkmp:
1072                 pseudoflavor = RPC_AUTH_GSS_SPKMP;
1073                 break;
1074         default:
1075                 return 0;
1076         }
1077
1078         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1079         nfs_set_auth_parsed_mount_data(mnt, pseudoflavor);
1080         return 1;
1081 }
1082
1083 static int nfs_parse_version_string(char *string,
1084                 struct nfs_parsed_mount_data *mnt,
1085                 substring_t *args)
1086 {
1087         mnt->flags &= ~NFS_MOUNT_VER3;
1088         switch (match_token(string, nfs_vers_tokens, args)) {
1089         case Opt_vers_2:
1090                 mnt->version = 2;
1091                 break;
1092         case Opt_vers_3:
1093                 mnt->flags |= NFS_MOUNT_VER3;
1094                 mnt->version = 3;
1095                 break;
1096         case Opt_vers_4:
1097                 /* Backward compatibility option. In future,
1098                  * the mount program should always supply
1099                  * a NFSv4 minor version number.
1100                  */
1101                 mnt->version = 4;
1102                 break;
1103         case Opt_vers_4_0:
1104                 mnt->version = 4;
1105                 mnt->minorversion = 0;
1106                 break;
1107         case Opt_vers_4_1:
1108                 mnt->version = 4;
1109                 mnt->minorversion = 1;
1110                 break;
1111         case Opt_vers_4_2:
1112                 mnt->version = 4;
1113                 mnt->minorversion = 2;
1114                 break;
1115         default:
1116                 return 0;
1117         }
1118         return 1;
1119 }
1120
1121 static int nfs_get_option_str(substring_t args[], char **option)
1122 {
1123         kfree(*option);
1124         *option = match_strdup(args);
1125         return !*option;
1126 }
1127
1128 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1129 {
1130         int rc;
1131         char *string;
1132
1133         string = match_strdup(args);
1134         if (string == NULL)
1135                 return -ENOMEM;
1136         rc = kstrtoul(string, 10, option);
1137         kfree(string);
1138
1139         return rc;
1140 }
1141
1142 /*
1143  * Error-check and convert a string of mount options from user space into
1144  * a data structure.  The whole mount string is processed; bad options are
1145  * skipped as they are encountered.  If there were no errors, return 1;
1146  * otherwise return 0 (zero).
1147  */
1148 static int nfs_parse_mount_options(char *raw,
1149                                    struct nfs_parsed_mount_data *mnt)
1150 {
1151         char *p, *string, *secdata;
1152         int rc, sloppy = 0, invalid_option = 0;
1153         unsigned short protofamily = AF_UNSPEC;
1154         unsigned short mountfamily = AF_UNSPEC;
1155
1156         if (!raw) {
1157                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1158                 return 1;
1159         }
1160         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1161
1162         secdata = alloc_secdata();
1163         if (!secdata)
1164                 goto out_nomem;
1165
1166         rc = security_sb_copy_data(raw, secdata);
1167         if (rc)
1168                 goto out_security_failure;
1169
1170         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1171         if (rc)
1172                 goto out_security_failure;
1173
1174         free_secdata(secdata);
1175
1176         while ((p = strsep(&raw, ",")) != NULL) {
1177                 substring_t args[MAX_OPT_ARGS];
1178                 unsigned long option;
1179                 int token;
1180
1181                 if (!*p)
1182                         continue;
1183
1184                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1185
1186                 token = match_token(p, nfs_mount_option_tokens, args);
1187                 switch (token) {
1188
1189                 /*
1190                  * boolean options:  foo/nofoo
1191                  */
1192                 case Opt_soft:
1193                         mnt->flags |= NFS_MOUNT_SOFT;
1194                         break;
1195                 case Opt_hard:
1196                         mnt->flags &= ~NFS_MOUNT_SOFT;
1197                         break;
1198                 case Opt_posix:
1199                         mnt->flags |= NFS_MOUNT_POSIX;
1200                         break;
1201                 case Opt_noposix:
1202                         mnt->flags &= ~NFS_MOUNT_POSIX;
1203                         break;
1204                 case Opt_cto:
1205                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1206                         break;
1207                 case Opt_nocto:
1208                         mnt->flags |= NFS_MOUNT_NOCTO;
1209                         break;
1210                 case Opt_ac:
1211                         mnt->flags &= ~NFS_MOUNT_NOAC;
1212                         break;
1213                 case Opt_noac:
1214                         mnt->flags |= NFS_MOUNT_NOAC;
1215                         break;
1216                 case Opt_lock:
1217                         mnt->flags &= ~NFS_MOUNT_NONLM;
1218                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1219                                         NFS_MOUNT_LOCAL_FCNTL);
1220                         break;
1221                 case Opt_nolock:
1222                         mnt->flags |= NFS_MOUNT_NONLM;
1223                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1224                                        NFS_MOUNT_LOCAL_FCNTL);
1225                         break;
1226                 case Opt_udp:
1227                         mnt->flags &= ~NFS_MOUNT_TCP;
1228                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1229                         break;
1230                 case Opt_tcp:
1231                         mnt->flags |= NFS_MOUNT_TCP;
1232                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1233                         break;
1234                 case Opt_rdma:
1235                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1236                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1237                         xprt_load_transport(p);
1238                         break;
1239                 case Opt_acl:
1240                         mnt->flags &= ~NFS_MOUNT_NOACL;
1241                         break;
1242                 case Opt_noacl:
1243                         mnt->flags |= NFS_MOUNT_NOACL;
1244                         break;
1245                 case Opt_rdirplus:
1246                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1247                         break;
1248                 case Opt_nordirplus:
1249                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1250                         break;
1251                 case Opt_sharecache:
1252                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1253                         break;
1254                 case Opt_nosharecache:
1255                         mnt->flags |= NFS_MOUNT_UNSHARED;
1256                         break;
1257                 case Opt_resvport:
1258                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1259                         break;
1260                 case Opt_noresvport:
1261                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1262                         break;
1263                 case Opt_fscache:
1264                         mnt->options |= NFS_OPTION_FSCACHE;
1265                         kfree(mnt->fscache_uniq);
1266                         mnt->fscache_uniq = NULL;
1267                         break;
1268                 case Opt_nofscache:
1269                         mnt->options &= ~NFS_OPTION_FSCACHE;
1270                         kfree(mnt->fscache_uniq);
1271                         mnt->fscache_uniq = NULL;
1272                         break;
1273                 case Opt_migration:
1274                         mnt->options |= NFS_OPTION_MIGRATION;
1275                         break;
1276                 case Opt_nomigration:
1277                         mnt->options &= NFS_OPTION_MIGRATION;
1278                         break;
1279
1280                 /*
1281                  * options that take numeric values
1282                  */
1283                 case Opt_port:
1284                         if (nfs_get_option_ul(args, &option) ||
1285                             option > USHRT_MAX)
1286                                 goto out_invalid_value;
1287                         mnt->nfs_server.port = option;
1288                         break;
1289                 case Opt_rsize:
1290                         if (nfs_get_option_ul(args, &option))
1291                                 goto out_invalid_value;
1292                         mnt->rsize = option;
1293                         break;
1294                 case Opt_wsize:
1295                         if (nfs_get_option_ul(args, &option))
1296                                 goto out_invalid_value;
1297                         mnt->wsize = option;
1298                         break;
1299                 case Opt_bsize:
1300                         if (nfs_get_option_ul(args, &option))
1301                                 goto out_invalid_value;
1302                         mnt->bsize = option;
1303                         break;
1304                 case Opt_timeo:
1305                         if (nfs_get_option_ul(args, &option) || option == 0)
1306                                 goto out_invalid_value;
1307                         mnt->timeo = option;
1308                         break;
1309                 case Opt_retrans:
1310                         if (nfs_get_option_ul(args, &option) || option == 0)
1311                                 goto out_invalid_value;
1312                         mnt->retrans = option;
1313                         break;
1314                 case Opt_acregmin:
1315                         if (nfs_get_option_ul(args, &option))
1316                                 goto out_invalid_value;
1317                         mnt->acregmin = option;
1318                         break;
1319                 case Opt_acregmax:
1320                         if (nfs_get_option_ul(args, &option))
1321                                 goto out_invalid_value;
1322                         mnt->acregmax = option;
1323                         break;
1324                 case Opt_acdirmin:
1325                         if (nfs_get_option_ul(args, &option))
1326                                 goto out_invalid_value;
1327                         mnt->acdirmin = option;
1328                         break;
1329                 case Opt_acdirmax:
1330                         if (nfs_get_option_ul(args, &option))
1331                                 goto out_invalid_value;
1332                         mnt->acdirmax = option;
1333                         break;
1334                 case Opt_actimeo:
1335                         if (nfs_get_option_ul(args, &option))
1336                                 goto out_invalid_value;
1337                         mnt->acregmin = mnt->acregmax =
1338                         mnt->acdirmin = mnt->acdirmax = option;
1339                         break;
1340                 case Opt_namelen:
1341                         if (nfs_get_option_ul(args, &option))
1342                                 goto out_invalid_value;
1343                         mnt->namlen = option;
1344                         break;
1345                 case Opt_mountport:
1346                         if (nfs_get_option_ul(args, &option) ||
1347                             option > USHRT_MAX)
1348                                 goto out_invalid_value;
1349                         mnt->mount_server.port = option;
1350                         break;
1351                 case Opt_mountvers:
1352                         if (nfs_get_option_ul(args, &option) ||
1353                             option < NFS_MNT_VERSION ||
1354                             option > NFS_MNT3_VERSION)
1355                                 goto out_invalid_value;
1356                         mnt->mount_server.version = option;
1357                         break;
1358                 case Opt_minorversion:
1359                         if (nfs_get_option_ul(args, &option))
1360                                 goto out_invalid_value;
1361                         if (option > NFS4_MAX_MINOR_VERSION)
1362                                 goto out_invalid_value;
1363                         mnt->minorversion = option;
1364                         break;
1365
1366                 /*
1367                  * options that take text values
1368                  */
1369                 case Opt_nfsvers:
1370                         string = match_strdup(args);
1371                         if (string == NULL)
1372                                 goto out_nomem;
1373                         rc = nfs_parse_version_string(string, mnt, args);
1374                         kfree(string);
1375                         if (!rc)
1376                                 goto out_invalid_value;
1377                         break;
1378                 case Opt_sec:
1379                         string = match_strdup(args);
1380                         if (string == NULL)
1381                                 goto out_nomem;
1382                         rc = nfs_parse_security_flavors(string, mnt);
1383                         kfree(string);
1384                         if (!rc) {
1385                                 dfprintk(MOUNT, "NFS:   unrecognized "
1386                                                 "security flavor\n");
1387                                 return 0;
1388                         }
1389                         break;
1390                 case Opt_proto:
1391                         string = match_strdup(args);
1392                         if (string == NULL)
1393                                 goto out_nomem;
1394                         token = match_token(string,
1395                                             nfs_xprt_protocol_tokens, args);
1396
1397                         protofamily = AF_INET;
1398                         switch (token) {
1399                         case Opt_xprt_udp6:
1400                                 protofamily = AF_INET6;
1401                         case Opt_xprt_udp:
1402                                 mnt->flags &= ~NFS_MOUNT_TCP;
1403                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1404                                 break;
1405                         case Opt_xprt_tcp6:
1406                                 protofamily = AF_INET6;
1407                         case Opt_xprt_tcp:
1408                                 mnt->flags |= NFS_MOUNT_TCP;
1409                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1410                                 break;
1411                         case Opt_xprt_rdma:
1412                                 /* vector side protocols to TCP */
1413                                 mnt->flags |= NFS_MOUNT_TCP;
1414                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1415                                 xprt_load_transport(string);
1416                                 break;
1417                         default:
1418                                 dfprintk(MOUNT, "NFS:   unrecognized "
1419                                                 "transport protocol\n");
1420                                 kfree(string);
1421                                 return 0;
1422                         }
1423                         kfree(string);
1424                         break;
1425                 case Opt_mountproto:
1426                         string = match_strdup(args);
1427                         if (string == NULL)
1428                                 goto out_nomem;
1429                         token = match_token(string,
1430                                             nfs_xprt_protocol_tokens, args);
1431                         kfree(string);
1432
1433                         mountfamily = AF_INET;
1434                         switch (token) {
1435                         case Opt_xprt_udp6:
1436                                 mountfamily = AF_INET6;
1437                         case Opt_xprt_udp:
1438                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1439                                 break;
1440                         case Opt_xprt_tcp6:
1441                                 mountfamily = AF_INET6;
1442                         case Opt_xprt_tcp:
1443                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1444                                 break;
1445                         case Opt_xprt_rdma: /* not used for side protocols */
1446                         default:
1447                                 dfprintk(MOUNT, "NFS:   unrecognized "
1448                                                 "transport protocol\n");
1449                                 return 0;
1450                         }
1451                         break;
1452                 case Opt_addr:
1453                         string = match_strdup(args);
1454                         if (string == NULL)
1455                                 goto out_nomem;
1456                         mnt->nfs_server.addrlen =
1457                                 rpc_pton(mnt->net, string, strlen(string),
1458                                         (struct sockaddr *)
1459                                         &mnt->nfs_server.address,
1460                                         sizeof(mnt->nfs_server.address));
1461                         kfree(string);
1462                         if (mnt->nfs_server.addrlen == 0)
1463                                 goto out_invalid_address;
1464                         break;
1465                 case Opt_clientaddr:
1466                         if (nfs_get_option_str(args, &mnt->client_address))
1467                                 goto out_nomem;
1468                         break;
1469                 case Opt_mounthost:
1470                         if (nfs_get_option_str(args,
1471                                                &mnt->mount_server.hostname))
1472                                 goto out_nomem;
1473                         break;
1474                 case Opt_mountaddr:
1475                         string = match_strdup(args);
1476                         if (string == NULL)
1477                                 goto out_nomem;
1478                         mnt->mount_server.addrlen =
1479                                 rpc_pton(mnt->net, string, strlen(string),
1480                                         (struct sockaddr *)
1481                                         &mnt->mount_server.address,
1482                                         sizeof(mnt->mount_server.address));
1483                         kfree(string);
1484                         if (mnt->mount_server.addrlen == 0)
1485                                 goto out_invalid_address;
1486                         break;
1487                 case Opt_lookupcache:
1488                         string = match_strdup(args);
1489                         if (string == NULL)
1490                                 goto out_nomem;
1491                         token = match_token(string,
1492                                         nfs_lookupcache_tokens, args);
1493                         kfree(string);
1494                         switch (token) {
1495                                 case Opt_lookupcache_all:
1496                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1497                                         break;
1498                                 case Opt_lookupcache_positive:
1499                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1500                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1501                                         break;
1502                                 case Opt_lookupcache_none:
1503                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1504                                         break;
1505                                 default:
1506                                         dfprintk(MOUNT, "NFS:   invalid "
1507                                                         "lookupcache argument\n");
1508                                         return 0;
1509                         };
1510                         break;
1511                 case Opt_fscache_uniq:
1512                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1513                                 goto out_nomem;
1514                         mnt->options |= NFS_OPTION_FSCACHE;
1515                         break;
1516                 case Opt_local_lock:
1517                         string = match_strdup(args);
1518                         if (string == NULL)
1519                                 goto out_nomem;
1520                         token = match_token(string, nfs_local_lock_tokens,
1521                                         args);
1522                         kfree(string);
1523                         switch (token) {
1524                         case Opt_local_lock_all:
1525                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1526                                                NFS_MOUNT_LOCAL_FCNTL);
1527                                 break;
1528                         case Opt_local_lock_flock:
1529                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1530                                 break;
1531                         case Opt_local_lock_posix:
1532                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1533                                 break;
1534                         case Opt_local_lock_none:
1535                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1536                                                 NFS_MOUNT_LOCAL_FCNTL);
1537                                 break;
1538                         default:
1539                                 dfprintk(MOUNT, "NFS:   invalid "
1540                                                 "local_lock argument\n");
1541                                 return 0;
1542                         };
1543                         break;
1544
1545                 /*
1546                  * Special options
1547                  */
1548                 case Opt_sloppy:
1549                         sloppy = 1;
1550                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1551                         break;
1552                 case Opt_userspace:
1553                 case Opt_deprecated:
1554                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1555                                         "'%s'\n", p);
1556                         break;
1557
1558                 default:
1559                         invalid_option = 1;
1560                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1561                                         "'%s'\n", p);
1562                 }
1563         }
1564
1565         if (!sloppy && invalid_option)
1566                 return 0;
1567
1568         if (mnt->minorversion && mnt->version != 4)
1569                 goto out_minorversion_mismatch;
1570
1571         if (mnt->options & NFS_OPTION_MIGRATION &&
1572             mnt->version != 4 && mnt->minorversion != 0)
1573                 goto out_migration_misuse;
1574
1575         /*
1576          * verify that any proto=/mountproto= options match the address
1577          * families in the addr=/mountaddr= options.
1578          */
1579         if (protofamily != AF_UNSPEC &&
1580             protofamily != mnt->nfs_server.address.ss_family)
1581                 goto out_proto_mismatch;
1582
1583         if (mountfamily != AF_UNSPEC) {
1584                 if (mnt->mount_server.addrlen) {
1585                         if (mountfamily != mnt->mount_server.address.ss_family)
1586                                 goto out_mountproto_mismatch;
1587                 } else {
1588                         if (mountfamily != mnt->nfs_server.address.ss_family)
1589                                 goto out_mountproto_mismatch;
1590                 }
1591         }
1592
1593         return 1;
1594
1595 out_mountproto_mismatch:
1596         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1597                          "option\n");
1598         return 0;
1599 out_proto_mismatch:
1600         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1601         return 0;
1602 out_invalid_address:
1603         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1604         return 0;
1605 out_invalid_value:
1606         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1607         return 0;
1608 out_minorversion_mismatch:
1609         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1610                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1611         return 0;
1612 out_migration_misuse:
1613         printk(KERN_INFO
1614                 "NFS: 'migration' not supported for this NFS version\n");
1615         return 0;
1616 out_nomem:
1617         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1618         return 0;
1619 out_security_failure:
1620         free_secdata(secdata);
1621         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1622         return 0;
1623 }
1624
1625 /*
1626  * Ensure that the specified authtype in args->auth_flavors[0] is supported by
1627  * the server. Returns 0 if it's ok, and -EACCES if not.
1628  */
1629 static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
1630                         rpc_authflavor_t *server_authlist, unsigned int count)
1631 {
1632         unsigned int i;
1633
1634         /*
1635          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1636          * must be in the list returned by the server.
1637          *
1638          * AUTH_NULL has a special meaning when it's in the server list - it
1639          * means that the server will ignore the rpc creds, so any flavor
1640          * can be used.
1641          */
1642         for (i = 0; i < count; i++) {
1643                 if (args->auth_flavors[0] == server_authlist[i] ||
1644                     server_authlist[i] == RPC_AUTH_NULL)
1645                         goto out;
1646         }
1647
1648         dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
1649                 args->auth_flavors[0]);
1650         return -EACCES;
1651
1652 out:
1653         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1654         return 0;
1655 }
1656
1657 /*
1658  * Use the remote server's MOUNT service to request the NFS file handle
1659  * corresponding to the provided path.
1660  */
1661 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1662                              struct nfs_fh *root_fh,
1663                              rpc_authflavor_t *server_authlist,
1664                              unsigned int *server_authlist_len)
1665 {
1666         struct nfs_mount_request request = {
1667                 .sap            = (struct sockaddr *)
1668                                                 &args->mount_server.address,
1669                 .dirpath        = args->nfs_server.export_path,
1670                 .protocol       = args->mount_server.protocol,
1671                 .fh             = root_fh,
1672                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1673                 .auth_flav_len  = server_authlist_len,
1674                 .auth_flavs     = server_authlist,
1675                 .net            = args->net,
1676         };
1677         int status;
1678
1679         if (args->mount_server.version == 0) {
1680                 switch (args->version) {
1681                         default:
1682                                 args->mount_server.version = NFS_MNT3_VERSION;
1683                                 break;
1684                         case 2:
1685                                 args->mount_server.version = NFS_MNT_VERSION;
1686                 }
1687         }
1688         request.version = args->mount_server.version;
1689
1690         if (args->mount_server.hostname)
1691                 request.hostname = args->mount_server.hostname;
1692         else
1693                 request.hostname = args->nfs_server.hostname;
1694
1695         /*
1696          * Construct the mount server's address.
1697          */
1698         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1699                 memcpy(request.sap, &args->nfs_server.address,
1700                        args->nfs_server.addrlen);
1701                 args->mount_server.addrlen = args->nfs_server.addrlen;
1702         }
1703         request.salen = args->mount_server.addrlen;
1704         nfs_set_port(request.sap, &args->mount_server.port, 0);
1705
1706         /*
1707          * Now ask the mount server to map our export path
1708          * to a file handle.
1709          */
1710         status = nfs_mount(&request);
1711         if (status != 0) {
1712                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1713                                 request.hostname, status);
1714                 return status;
1715         }
1716
1717         return 0;
1718 }
1719
1720 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1721                                         struct nfs_subversion *nfs_mod)
1722 {
1723         int status;
1724         unsigned int i;
1725         bool tried_auth_unix = false;
1726         bool auth_null_in_list = false;
1727         struct nfs_server *server = ERR_PTR(-EACCES);
1728         struct nfs_parsed_mount_data *args = mount_info->parsed;
1729         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1730         unsigned int authlist_len = ARRAY_SIZE(authlist);
1731
1732         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1733                                         &authlist_len);
1734         if (status)
1735                 return ERR_PTR(status);
1736
1737         /*
1738          * Was a sec= authflavor specified in the options? First, verify
1739          * whether the server supports it, and then just try to use it if so.
1740          */
1741         if (args->auth_flavor_len > 0) {
1742                 status = nfs_verify_authflavor(args, authlist, authlist_len);
1743                 dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1744                 if (status)
1745                         return ERR_PTR(status);
1746                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1747         }
1748
1749         /*
1750          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1751          * SHOULD prefer the flavor listed first. However, some servers list
1752          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1753          */
1754         for (i = 0; i < authlist_len; ++i) {
1755                 rpc_authflavor_t flavor;
1756                 struct rpcsec_gss_info info;
1757
1758                 flavor = authlist[i];
1759                 switch (flavor) {
1760                 case RPC_AUTH_UNIX:
1761                         tried_auth_unix = true;
1762                         break;
1763                 case RPC_AUTH_NULL:
1764                         auth_null_in_list = true;
1765                         continue;
1766                 default:
1767                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1768                                 continue;
1769                         /* Fallthrough */
1770                 }
1771                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1772                 nfs_set_auth_parsed_mount_data(args, flavor);
1773                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1774                 if (!IS_ERR(server))
1775                         return server;
1776         }
1777
1778         /*
1779          * Nothing we tried so far worked. At this point, give up if we've
1780          * already tried AUTH_UNIX or if the server's list doesn't contain
1781          * AUTH_NULL
1782          */
1783         if (tried_auth_unix || !auth_null_in_list)
1784                 return server;
1785
1786         /* Last chance! Try AUTH_UNIX */
1787         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1788         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1789         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1790 }
1791
1792 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1793                              struct nfs_mount_info *mount_info,
1794                              struct nfs_subversion *nfs_mod)
1795 {
1796         struct nfs_server *server;
1797
1798         if (mount_info->parsed->need_mount)
1799                 server = nfs_try_mount_request(mount_info, nfs_mod);
1800         else
1801                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1802
1803         if (IS_ERR(server))
1804                 return ERR_CAST(server);
1805
1806         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1807 }
1808 EXPORT_SYMBOL_GPL(nfs_try_mount);
1809
1810 /*
1811  * Split "dev_name" into "hostname:export_path".
1812  *
1813  * The leftmost colon demarks the split between the server's hostname
1814  * and the export path.  If the hostname starts with a left square
1815  * bracket, then it may contain colons.
1816  *
1817  * Note: caller frees hostname and export path, even on error.
1818  */
1819 static int nfs_parse_devname(const char *dev_name,
1820                              char **hostname, size_t maxnamlen,
1821                              char **export_path, size_t maxpathlen)
1822 {
1823         size_t len;
1824         char *end;
1825
1826         /* Is the host name protected with square brakcets? */
1827         if (*dev_name == '[') {
1828                 end = strchr(++dev_name, ']');
1829                 if (end == NULL || end[1] != ':')
1830                         goto out_bad_devname;
1831
1832                 len = end - dev_name;
1833                 end++;
1834         } else {
1835                 char *comma;
1836
1837                 end = strchr(dev_name, ':');
1838                 if (end == NULL)
1839                         goto out_bad_devname;
1840                 len = end - dev_name;
1841
1842                 /* kill possible hostname list: not supported */
1843                 comma = strchr(dev_name, ',');
1844                 if (comma != NULL && comma < end)
1845                         *comma = 0;
1846         }
1847
1848         if (len > maxnamlen)
1849                 goto out_hostname;
1850
1851         /* N.B. caller will free nfs_server.hostname in all cases */
1852         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1853         if (*hostname == NULL)
1854                 goto out_nomem;
1855         len = strlen(++end);
1856         if (len > maxpathlen)
1857                 goto out_path;
1858         *export_path = kstrndup(end, len, GFP_KERNEL);
1859         if (!*export_path)
1860                 goto out_nomem;
1861
1862         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1863         return 0;
1864
1865 out_bad_devname:
1866         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1867         return -EINVAL;
1868
1869 out_nomem:
1870         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1871         return -ENOMEM;
1872
1873 out_hostname:
1874         dfprintk(MOUNT, "NFS: server hostname too long\n");
1875         return -ENAMETOOLONG;
1876
1877 out_path:
1878         dfprintk(MOUNT, "NFS: export pathname too long\n");
1879         return -ENAMETOOLONG;
1880 }
1881
1882 /*
1883  * Validate the NFS2/NFS3 mount data
1884  * - fills in the mount root filehandle
1885  *
1886  * For option strings, user space handles the following behaviors:
1887  *
1888  * + DNS: mapping server host name to IP address ("addr=" option)
1889  *
1890  * + failure mode: how to behave if a mount request can't be handled
1891  *   immediately ("fg/bg" option)
1892  *
1893  * + retry: how often to retry a mount request ("retry=" option)
1894  *
1895  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1896  *   mountproto=tcp after mountproto=udp, and so on
1897  */
1898 static int nfs23_validate_mount_data(void *options,
1899                                      struct nfs_parsed_mount_data *args,
1900                                      struct nfs_fh *mntfh,
1901                                      const char *dev_name)
1902 {
1903         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1904         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1905         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1906
1907         if (data == NULL)
1908                 goto out_no_data;
1909
1910         args->version = NFS_DEFAULT_VERSION;
1911         switch (data->version) {
1912         case 1:
1913                 data->namlen = 0;
1914         case 2:
1915                 data->bsize = 0;
1916         case 3:
1917                 if (data->flags & NFS_MOUNT_VER3)
1918                         goto out_no_v3;
1919                 data->root.size = NFS2_FHSIZE;
1920                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1921                 /* Turn off security negotiation */
1922                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1923         case 4:
1924                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1925                         goto out_no_sec;
1926         case 5:
1927                 memset(data->context, 0, sizeof(data->context));
1928         case 6:
1929                 if (data->flags & NFS_MOUNT_VER3) {
1930                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1931                                 goto out_invalid_fh;
1932                         mntfh->size = data->root.size;
1933                         args->version = 3;
1934                 } else {
1935                         mntfh->size = NFS2_FHSIZE;
1936                         args->version = 2;
1937                 }
1938
1939
1940                 memcpy(mntfh->data, data->root.data, mntfh->size);
1941                 if (mntfh->size < sizeof(mntfh->data))
1942                         memset(mntfh->data + mntfh->size, 0,
1943                                sizeof(mntfh->data) - mntfh->size);
1944
1945                 /*
1946                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1947                  * can deal with.
1948                  */
1949                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1950                 args->flags             |= extra_flags;
1951                 args->rsize             = data->rsize;
1952                 args->wsize             = data->wsize;
1953                 args->timeo             = data->timeo;
1954                 args->retrans           = data->retrans;
1955                 args->acregmin          = data->acregmin;
1956                 args->acregmax          = data->acregmax;
1957                 args->acdirmin          = data->acdirmin;
1958                 args->acdirmax          = data->acdirmax;
1959                 args->need_mount        = false;
1960
1961                 memcpy(sap, &data->addr, sizeof(data->addr));
1962                 args->nfs_server.addrlen = sizeof(data->addr);
1963                 args->nfs_server.port = ntohs(data->addr.sin_port);
1964                 if (!nfs_verify_server_address(sap))
1965                         goto out_no_address;
1966
1967                 if (!(data->flags & NFS_MOUNT_TCP))
1968                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1969                 /* N.B. caller will free nfs_server.hostname in all cases */
1970                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1971                 args->namlen            = data->namlen;
1972                 args->bsize             = data->bsize;
1973
1974                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1975                         nfs_set_auth_parsed_mount_data(args, data->pseudoflavor);
1976                 else
1977                         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1978                 if (!args->nfs_server.hostname)
1979                         goto out_nomem;
1980
1981                 if (!(data->flags & NFS_MOUNT_NONLM))
1982                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1983                                          NFS_MOUNT_LOCAL_FCNTL);
1984                 else
1985                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1986                                         NFS_MOUNT_LOCAL_FCNTL);
1987                 /*
1988                  * The legacy version 6 binary mount data from userspace has a
1989                  * field used only to transport selinux information into the
1990                  * the kernel.  To continue to support that functionality we
1991                  * have a touch of selinux knowledge here in the NFS code. The
1992                  * userspace code converted context=blah to just blah so we are
1993                  * converting back to the full string selinux understands.
1994                  */
1995                 if (data->context[0]){
1996 #ifdef CONFIG_SECURITY_SELINUX
1997                         int rc;
1998                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1999                         if (!opts_str)
2000                                 return -ENOMEM;
2001                         strcpy(opts_str, "context=");
2002                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2003                         strcat(opts_str, &data->context[0]);
2004                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2005                         kfree(opts_str);
2006                         if (rc)
2007                                 return rc;
2008 #else
2009                         return -EINVAL;
2010 #endif
2011                 }
2012
2013                 break;
2014         default:
2015                 return NFS_TEXT_DATA;
2016         }
2017
2018 #if !IS_ENABLED(CONFIG_NFS_V3)
2019         if (args->version == 3)
2020                 goto out_v3_not_compiled;
2021 #endif /* !CONFIG_NFS_V3 */
2022
2023         return 0;
2024
2025 out_no_data:
2026         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2027         return -EINVAL;
2028
2029 out_no_v3:
2030         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2031                  data->version);
2032         return -EINVAL;
2033
2034 out_no_sec:
2035         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2036         return -EINVAL;
2037
2038 #if !IS_ENABLED(CONFIG_NFS_V3)
2039 out_v3_not_compiled:
2040         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2041         return -EPROTONOSUPPORT;
2042 #endif /* !CONFIG_NFS_V3 */
2043
2044 out_nomem:
2045         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2046         return -ENOMEM;
2047
2048 out_no_address:
2049         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2050         return -EINVAL;
2051
2052 out_invalid_fh:
2053         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2054         return -EINVAL;
2055 }
2056
2057 #if IS_ENABLED(CONFIG_NFS_V4)
2058 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2059                                    void *options,
2060                                    struct nfs_parsed_mount_data *args,
2061                                    struct nfs_fh *mntfh,
2062                                    const char *dev_name)
2063 {
2064         if (fs_type == &nfs_fs_type)
2065                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2066         return nfs4_validate_mount_data(options, args, dev_name);
2067 }
2068 #else
2069 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2070                                    void *options,
2071                                    struct nfs_parsed_mount_data *args,
2072                                    struct nfs_fh *mntfh,
2073                                    const char *dev_name)
2074 {
2075         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2076 }
2077 #endif
2078
2079 static int nfs_validate_text_mount_data(void *options,
2080                                         struct nfs_parsed_mount_data *args,
2081                                         const char *dev_name)
2082 {
2083         int port = 0;
2084         int max_namelen = PAGE_SIZE;
2085         int max_pathlen = NFS_MAXPATHLEN;
2086         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2087
2088         if (nfs_parse_mount_options((char *)options, args) == 0)
2089                 return -EINVAL;
2090
2091         if (!nfs_verify_server_address(sap))
2092                 goto out_no_address;
2093
2094         if (args->version == 4) {
2095 #if IS_ENABLED(CONFIG_NFS_V4)
2096                 port = NFS_PORT;
2097                 max_namelen = NFS4_MAXNAMLEN;
2098                 max_pathlen = NFS4_MAXPATHLEN;
2099                 nfs_validate_transport_protocol(args);
2100                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2101                         goto out_invalid_transport_udp;
2102                 nfs4_validate_mount_flags(args);
2103 #else
2104                 goto out_v4_not_compiled;
2105 #endif /* CONFIG_NFS_V4 */
2106         } else
2107                 nfs_set_mount_transport_protocol(args);
2108
2109         nfs_set_port(sap, &args->nfs_server.port, port);
2110
2111         if (args->auth_flavor_len > 1)
2112                 goto out_bad_auth;
2113
2114         return nfs_parse_devname(dev_name,
2115                                    &args->nfs_server.hostname,
2116                                    max_namelen,
2117                                    &args->nfs_server.export_path,
2118                                    max_pathlen);
2119
2120 #if !IS_ENABLED(CONFIG_NFS_V4)
2121 out_v4_not_compiled:
2122         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2123         return -EPROTONOSUPPORT;
2124 #else
2125 out_invalid_transport_udp:
2126         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2127         return -EINVAL;
2128 #endif /* !CONFIG_NFS_V4 */
2129
2130 out_no_address:
2131         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2132         return -EINVAL;
2133
2134 out_bad_auth:
2135         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2136         return -EINVAL;
2137 }
2138
2139 static int
2140 nfs_compare_remount_data(struct nfs_server *nfss,
2141                          struct nfs_parsed_mount_data *data)
2142 {
2143         if (data->flags != nfss->flags ||
2144             data->rsize != nfss->rsize ||
2145             data->wsize != nfss->wsize ||
2146             data->retrans != nfss->client->cl_timeout->to_retries ||
2147             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2148             data->acregmin != nfss->acregmin / HZ ||
2149             data->acregmax != nfss->acregmax / HZ ||
2150             data->acdirmin != nfss->acdirmin / HZ ||
2151             data->acdirmax != nfss->acdirmax / HZ ||
2152             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2153             data->nfs_server.port != nfss->port ||
2154             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2155             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2156                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2157                 return -EINVAL;
2158
2159         return 0;
2160 }
2161
2162 int
2163 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2164 {
2165         int error;
2166         struct nfs_server *nfss = sb->s_fs_info;
2167         struct nfs_parsed_mount_data *data;
2168         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2169         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2170         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2171
2172         /*
2173          * Userspace mount programs that send binary options generally send
2174          * them populated with default values. We have no way to know which
2175          * ones were explicitly specified. Fall back to legacy behavior and
2176          * just return success.
2177          */
2178         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2179             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2180                                            options->version <= 6))))
2181                 return 0;
2182
2183         data = kzalloc(sizeof(*data), GFP_KERNEL);
2184         if (data == NULL)
2185                 return -ENOMEM;
2186
2187         /* fill out struct with values from existing mount */
2188         data->flags = nfss->flags;
2189         data->rsize = nfss->rsize;
2190         data->wsize = nfss->wsize;
2191         data->retrans = nfss->client->cl_timeout->to_retries;
2192         nfs_set_auth_parsed_mount_data(data, nfss->client->cl_auth->au_flavor);
2193         data->acregmin = nfss->acregmin / HZ;
2194         data->acregmax = nfss->acregmax / HZ;
2195         data->acdirmin = nfss->acdirmin / HZ;
2196         data->acdirmax = nfss->acdirmax / HZ;
2197         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2198         data->nfs_server.port = nfss->port;
2199         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2200         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2201                 data->nfs_server.addrlen);
2202
2203         /* overwrite those values with any that were specified */
2204         error = nfs_parse_mount_options((char *)options, data);
2205         if (error < 0)
2206                 goto out;
2207
2208         /*
2209          * noac is a special case. It implies -o sync, but that's not
2210          * necessarily reflected in the mtab options. do_remount_sb
2211          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2212          * remount options, so we have to explicitly reset it.
2213          */
2214         if (data->flags & NFS_MOUNT_NOAC)
2215                 *flags |= MS_SYNCHRONOUS;
2216
2217         /* compare new mount options with old ones */
2218         error = nfs_compare_remount_data(nfss, data);
2219 out:
2220         kfree(data);
2221         return error;
2222 }
2223 EXPORT_SYMBOL_GPL(nfs_remount);
2224
2225 /*
2226  * Initialise the common bits of the superblock
2227  */
2228 inline void nfs_initialise_sb(struct super_block *sb)
2229 {
2230         struct nfs_server *server = NFS_SB(sb);
2231
2232         sb->s_magic = NFS_SUPER_MAGIC;
2233
2234         /* We probably want something more informative here */
2235         snprintf(sb->s_id, sizeof(sb->s_id),
2236                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2237
2238         if (sb->s_blocksize == 0)
2239                 sb->s_blocksize = nfs_block_bits(server->wsize,
2240                                                  &sb->s_blocksize_bits);
2241
2242         sb->s_bdi = &server->backing_dev_info;
2243
2244         nfs_super_set_maxbytes(sb, server->maxfilesize);
2245 }
2246
2247 /*
2248  * Finish setting up an NFS2/3 superblock
2249  */
2250 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2251 {
2252         struct nfs_parsed_mount_data *data = mount_info->parsed;
2253         struct nfs_server *server = NFS_SB(sb);
2254
2255         sb->s_blocksize_bits = 0;
2256         sb->s_blocksize = 0;
2257         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2258         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2259         if (data && data->bsize)
2260                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2261
2262         if (server->nfs_client->rpc_ops->version != 2) {
2263                 /* The VFS shouldn't apply the umask to mode bits. We will do
2264                  * so ourselves when necessary.
2265                  */
2266                 sb->s_flags |= MS_POSIXACL;
2267                 sb->s_time_gran = 1;
2268         }
2269
2270         nfs_initialise_sb(sb);
2271 }
2272 EXPORT_SYMBOL_GPL(nfs_fill_super);
2273
2274 /*
2275  * Finish setting up a cloned NFS2/3/4 superblock
2276  */
2277 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2278 {
2279         const struct super_block *old_sb = mount_info->cloned->sb;
2280         struct nfs_server *server = NFS_SB(sb);
2281
2282         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2283         sb->s_blocksize = old_sb->s_blocksize;
2284         sb->s_maxbytes = old_sb->s_maxbytes;
2285         sb->s_xattr = old_sb->s_xattr;
2286         sb->s_op = old_sb->s_op;
2287         sb->s_time_gran = 1;
2288
2289         if (server->nfs_client->rpc_ops->version != 2) {
2290                 /* The VFS shouldn't apply the umask to mode bits. We will do
2291                  * so ourselves when necessary.
2292                  */
2293                 sb->s_flags |= MS_POSIXACL;
2294         }
2295
2296         nfs_initialise_sb(sb);
2297 }
2298
2299 #define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2300                 | NFS_MOUNT_SECURE \
2301                 | NFS_MOUNT_TCP \
2302                 | NFS_MOUNT_VER3 \
2303                 | NFS_MOUNT_KERBEROS \
2304                 | NFS_MOUNT_NONLM \
2305                 | NFS_MOUNT_BROKEN_SUID \
2306                 | NFS_MOUNT_STRICTLOCK \
2307                 | NFS_MOUNT_UNSHARED \
2308                 | NFS_MOUNT_NORESVPORT \
2309                 | NFS_MOUNT_LEGACY_INTERFACE)
2310
2311 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2312 {
2313         const struct nfs_server *a = s->s_fs_info;
2314         const struct rpc_clnt *clnt_a = a->client;
2315         const struct rpc_clnt *clnt_b = b->client;
2316
2317         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2318                 goto Ebusy;
2319         if (a->nfs_client != b->nfs_client)
2320                 goto Ebusy;
2321         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2322                 goto Ebusy;
2323         if (a->wsize != b->wsize)
2324                 goto Ebusy;
2325         if (a->rsize != b->rsize)
2326                 goto Ebusy;
2327         if (a->acregmin != b->acregmin)
2328                 goto Ebusy;
2329         if (a->acregmax != b->acregmax)
2330                 goto Ebusy;
2331         if (a->acdirmin != b->acdirmin)
2332                 goto Ebusy;
2333         if (a->acdirmax != b->acdirmax)
2334                 goto Ebusy;
2335         if (b->flags & NFS_MOUNT_SECFLAVOUR &&
2336            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2337                 goto Ebusy;
2338         return 1;
2339 Ebusy:
2340         return 0;
2341 }
2342
2343 struct nfs_sb_mountdata {
2344         struct nfs_server *server;
2345         int mntflags;
2346 };
2347
2348 static int nfs_set_super(struct super_block *s, void *data)
2349 {
2350         struct nfs_sb_mountdata *sb_mntdata = data;
2351         struct nfs_server *server = sb_mntdata->server;
2352         int ret;
2353
2354         s->s_flags = sb_mntdata->mntflags;
2355         s->s_fs_info = server;
2356         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2357         ret = set_anon_super(s, server);
2358         if (ret == 0)
2359                 server->s_dev = s->s_dev;
2360         return ret;
2361 }
2362
2363 static int nfs_compare_super_address(struct nfs_server *server1,
2364                                      struct nfs_server *server2)
2365 {
2366         struct sockaddr *sap1, *sap2;
2367
2368         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2369         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2370
2371         if (sap1->sa_family != sap2->sa_family)
2372                 return 0;
2373
2374         switch (sap1->sa_family) {
2375         case AF_INET: {
2376                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2377                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2378                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2379                         return 0;
2380                 if (sin1->sin_port != sin2->sin_port)
2381                         return 0;
2382                 break;
2383         }
2384         case AF_INET6: {
2385                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2386                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2387                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2388                         return 0;
2389                 if (sin1->sin6_port != sin2->sin6_port)
2390                         return 0;
2391                 break;
2392         }
2393         default:
2394                 return 0;
2395         }
2396
2397         return 1;
2398 }
2399
2400 static int nfs_compare_super(struct super_block *sb, void *data)
2401 {
2402         struct nfs_sb_mountdata *sb_mntdata = data;
2403         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2404         int mntflags = sb_mntdata->mntflags;
2405
2406         if (!nfs_compare_super_address(old, server))
2407                 return 0;
2408         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2409         if (old->flags & NFS_MOUNT_UNSHARED)
2410                 return 0;
2411         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2412                 return 0;
2413         return nfs_compare_mount_options(sb, server, mntflags);
2414 }
2415
2416 #ifdef CONFIG_NFS_FSCACHE
2417 static void nfs_get_cache_cookie(struct super_block *sb,
2418                                  struct nfs_parsed_mount_data *parsed,
2419                                  struct nfs_clone_mount *cloned)
2420 {
2421         struct nfs_server *nfss = NFS_SB(sb);
2422         char *uniq = NULL;
2423         int ulen = 0;
2424
2425         nfss->fscache_key = NULL;
2426         nfss->fscache = NULL;
2427
2428         if (parsed) {
2429                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2430                         return;
2431                 if (parsed->fscache_uniq) {
2432                         uniq = parsed->fscache_uniq;
2433                         ulen = strlen(parsed->fscache_uniq);
2434                 }
2435         } else if (cloned) {
2436                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2437                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2438                         return;
2439                 if (mnt_s->fscache_key) {
2440                         uniq = mnt_s->fscache_key->key.uniquifier;
2441                         ulen = mnt_s->fscache_key->key.uniq_len;
2442                 };
2443         } else
2444                 return;
2445
2446         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2447 }
2448 #else
2449 static void nfs_get_cache_cookie(struct super_block *sb,
2450                                  struct nfs_parsed_mount_data *parsed,
2451                                  struct nfs_clone_mount *cloned)
2452 {
2453 }
2454 #endif
2455
2456 static int nfs_bdi_register(struct nfs_server *server)
2457 {
2458         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2459 }
2460
2461 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2462                         struct nfs_mount_info *mount_info)
2463 {
2464         int error;
2465         unsigned long kflags = 0, kflags_out = 0;
2466         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2467                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2468
2469         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2470                                                 kflags, &kflags_out);
2471         if (error)
2472                 goto err;
2473
2474         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2475                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2476                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2477 err:
2478         return error;
2479 }
2480 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2481
2482 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2483                           struct nfs_mount_info *mount_info)
2484 {
2485         /* clone any lsm security options from the parent to the new sb */
2486         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2487                 return -ESTALE;
2488         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2489 }
2490 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2491
2492 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2493                                    int flags, const char *dev_name,
2494                                    struct nfs_mount_info *mount_info,
2495                                    struct nfs_subversion *nfs_mod)
2496 {
2497         struct super_block *s;
2498         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2499         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2500         struct nfs_sb_mountdata sb_mntdata = {
2501                 .mntflags = flags,
2502                 .server = server,
2503         };
2504         int error;
2505
2506         if (server->flags & NFS_MOUNT_UNSHARED)
2507                 compare_super = NULL;
2508
2509         /* -o noac implies -o sync */
2510         if (server->flags & NFS_MOUNT_NOAC)
2511                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2512
2513         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2514                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2515                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2516
2517         /* Get a superblock - note that we may end up sharing one that already exists */
2518         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2519         if (IS_ERR(s)) {
2520                 mntroot = ERR_CAST(s);
2521                 goto out_err_nosb;
2522         }
2523
2524         if (s->s_fs_info != server) {
2525                 nfs_free_server(server);
2526                 server = NULL;
2527         } else {
2528                 error = nfs_bdi_register(server);
2529                 if (error) {
2530                         mntroot = ERR_PTR(error);
2531                         goto error_splat_bdi;
2532                 }
2533         }
2534
2535         if (!s->s_root) {
2536                 /* initial superblock/root creation */
2537                 mount_info->fill_super(s, mount_info);
2538                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2539         }
2540
2541         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2542         if (IS_ERR(mntroot))
2543                 goto error_splat_super;
2544
2545         error = mount_info->set_security(s, mntroot, mount_info);
2546         if (error)
2547                 goto error_splat_root;
2548
2549         s->s_flags |= MS_ACTIVE;
2550
2551 out:
2552         return mntroot;
2553
2554 out_err_nosb:
2555         nfs_free_server(server);
2556         goto out;
2557
2558 error_splat_root:
2559         dput(mntroot);
2560         mntroot = ERR_PTR(error);
2561 error_splat_super:
2562         if (server && !s->s_root)
2563                 bdi_unregister(&server->backing_dev_info);
2564 error_splat_bdi:
2565         deactivate_locked_super(s);
2566         goto out;
2567 }
2568 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2569
2570 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2571         int flags, const char *dev_name, void *raw_data)
2572 {
2573         struct nfs_mount_info mount_info = {
2574                 .fill_super = nfs_fill_super,
2575                 .set_security = nfs_set_sb_security,
2576         };
2577         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2578         struct nfs_subversion *nfs_mod;
2579         int error;
2580
2581         mount_info.parsed = nfs_alloc_parsed_mount_data();
2582         mount_info.mntfh = nfs_alloc_fhandle();
2583         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2584                 goto out;
2585
2586         /* Validate the mount data */
2587         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2588         if (error == NFS_TEXT_DATA)
2589                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2590         if (error < 0) {
2591                 mntroot = ERR_PTR(error);
2592                 goto out;
2593         }
2594
2595         nfs_mod = get_nfs_version(mount_info.parsed->version);
2596         if (IS_ERR(nfs_mod)) {
2597                 mntroot = ERR_CAST(nfs_mod);
2598                 goto out;
2599         }
2600
2601         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2602
2603         put_nfs_version(nfs_mod);
2604 out:
2605         nfs_free_parsed_mount_data(mount_info.parsed);
2606         nfs_free_fhandle(mount_info.mntfh);
2607         return mntroot;
2608 }
2609 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2610
2611 /*
2612  * Ensure that we unregister the bdi before kill_anon_super
2613  * releases the device name
2614  */
2615 void nfs_put_super(struct super_block *s)
2616 {
2617         struct nfs_server *server = NFS_SB(s);
2618
2619         bdi_unregister(&server->backing_dev_info);
2620 }
2621 EXPORT_SYMBOL_GPL(nfs_put_super);
2622
2623 /*
2624  * Destroy an NFS2/3 superblock
2625  */
2626 void nfs_kill_super(struct super_block *s)
2627 {
2628         struct nfs_server *server = NFS_SB(s);
2629
2630         kill_anon_super(s);
2631         nfs_fscache_release_super_cookie(s);
2632         nfs_free_server(server);
2633 }
2634 EXPORT_SYMBOL_GPL(nfs_kill_super);
2635
2636 /*
2637  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2638  */
2639 static struct dentry *
2640 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2641                 const char *dev_name, void *raw_data)
2642 {
2643         struct nfs_clone_mount *data = raw_data;
2644         struct nfs_mount_info mount_info = {
2645                 .fill_super = nfs_clone_super,
2646                 .set_security = nfs_clone_sb_security,
2647                 .cloned = data,
2648         };
2649         struct nfs_server *server;
2650         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2651         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2652
2653         dprintk("--> nfs_xdev_mount()\n");
2654
2655         mount_info.mntfh = mount_info.cloned->fh;
2656
2657         /* create a new volume representation */
2658         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2659
2660         if (IS_ERR(server))
2661                 mntroot = ERR_CAST(server);
2662         else
2663                 mntroot = nfs_fs_mount_common(server, flags,
2664                                 dev_name, &mount_info, nfs_mod);
2665
2666         dprintk("<-- nfs_xdev_mount() = %ld\n",
2667                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2668         return mntroot;
2669 }
2670
2671 #if IS_ENABLED(CONFIG_NFS_V4)
2672
2673 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2674 {
2675         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2676                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2677 }
2678
2679 /*
2680  * Validate NFSv4 mount options
2681  */
2682 static int nfs4_validate_mount_data(void *options,
2683                                     struct nfs_parsed_mount_data *args,
2684                                     const char *dev_name)
2685 {
2686         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2687         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2688         char *c;
2689
2690         if (data == NULL)
2691                 goto out_no_data;
2692
2693         args->version = 4;
2694
2695         switch (data->version) {
2696         case 1:
2697                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2698                         goto out_no_address;
2699                 if (data->host_addrlen == 0)
2700                         goto out_no_address;
2701                 args->nfs_server.addrlen = data->host_addrlen;
2702                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2703                         return -EFAULT;
2704                 if (!nfs_verify_server_address(sap))
2705                         goto out_no_address;
2706                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2707
2708                 if (data->auth_flavourlen) {
2709                         rpc_authflavor_t pseudoflavor;
2710                         if (data->auth_flavourlen > 1)
2711                                 goto out_inval_auth;
2712                         if (copy_from_user(&pseudoflavor,
2713                                            data->auth_flavours,
2714                                            sizeof(pseudoflavor)))
2715                                 return -EFAULT;
2716                         nfs_set_auth_parsed_mount_data(args, pseudoflavor);
2717                 } else
2718                         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
2719
2720                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2721                 if (IS_ERR(c))
2722                         return PTR_ERR(c);
2723                 args->nfs_server.hostname = c;
2724
2725                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2726                 if (IS_ERR(c))
2727                         return PTR_ERR(c);
2728                 args->nfs_server.export_path = c;
2729                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2730
2731                 c = strndup_user(data->client_addr.data, 16);
2732                 if (IS_ERR(c))
2733                         return PTR_ERR(c);
2734                 args->client_address = c;
2735
2736                 /*
2737                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2738                  * can deal with.
2739                  */
2740
2741                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2742                 args->rsize     = data->rsize;
2743                 args->wsize     = data->wsize;
2744                 args->timeo     = data->timeo;
2745                 args->retrans   = data->retrans;
2746                 args->acregmin  = data->acregmin;
2747                 args->acregmax  = data->acregmax;
2748                 args->acdirmin  = data->acdirmin;
2749                 args->acdirmax  = data->acdirmax;
2750                 args->nfs_server.protocol = data->proto;
2751                 nfs_validate_transport_protocol(args);
2752                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2753                         goto out_invalid_transport_udp;
2754
2755                 break;
2756         default:
2757                 return NFS_TEXT_DATA;
2758         }
2759
2760         return 0;
2761
2762 out_no_data:
2763         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2764         return -EINVAL;
2765
2766 out_inval_auth:
2767         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2768                  data->auth_flavourlen);
2769         return -EINVAL;
2770
2771 out_no_address:
2772         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2773         return -EINVAL;
2774
2775 out_invalid_transport_udp:
2776         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2777         return -EINVAL;
2778 }
2779
2780 /*
2781  * NFS v4 module parameters need to stay in the
2782  * NFS client for backwards compatibility
2783  */
2784 unsigned int nfs_callback_set_tcpport;
2785 unsigned short nfs_callback_tcpport;
2786 /* Default cache timeout is 10 minutes */
2787 unsigned int nfs_idmap_cache_timeout = 600;
2788 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2789 bool nfs4_disable_idmapping = true;
2790 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2791 unsigned short send_implementation_id = 1;
2792 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2793 bool recover_lost_locks = false;
2794
2795 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2796 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2797 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2798 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2799 EXPORT_SYMBOL_GPL(max_session_slots);
2800 EXPORT_SYMBOL_GPL(send_implementation_id);
2801 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2802 EXPORT_SYMBOL_GPL(recover_lost_locks);
2803
2804 #define NFS_CALLBACK_MAXPORTNR (65535U)
2805
2806 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2807 {
2808         unsigned long num;
2809         int ret;
2810
2811         if (!val)
2812                 return -EINVAL;
2813         ret = kstrtoul(val, 0, &num);
2814         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2815                 return -EINVAL;
2816         *((unsigned int *)kp->arg) = num;
2817         return 0;
2818 }
2819 static struct kernel_param_ops param_ops_portnr = {
2820         .set = param_set_portnr,
2821         .get = param_get_uint,
2822 };
2823 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2824
2825 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2826 module_param(nfs_idmap_cache_timeout, int, 0644);
2827 module_param(nfs4_disable_idmapping, bool, 0644);
2828 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2829                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2830 MODULE_PARM_DESC(nfs4_disable_idmapping,
2831                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2832 module_param(max_session_slots, ushort, 0644);
2833 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2834                 "requests the client will negotiate");
2835 module_param(send_implementation_id, ushort, 0644);
2836 MODULE_PARM_DESC(send_implementation_id,
2837                 "Send implementation ID with NFSv4.1 exchange_id");
2838 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2839
2840 module_param(recover_lost_locks, bool, 0644);
2841 MODULE_PARM_DESC(recover_lost_locks,
2842                  "If the server reports that a lock might be lost, "
2843                  "try to recover it risking data corruption.");
2844
2845
2846 #endif /* CONFIG_NFS_V4 */