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