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/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/namei.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "pnfs.h"
  67 #include "nfs.h"
  68
  69 #define NFSDBG_FACILITY         NFSDBG_VFS
  70 #define NFS_TEXT_DATA           1
  71
  72 #if IS_ENABLED(CONFIG_NFS_V3)
  73 #define NFS_DEFAULT_VERSION 3
  74 #else
  75 #define NFS_DEFAULT_VERSION 2
  76 #endif
  77
  78 enum {
  79         /* Mount options that take no arguments */
  80         Opt_soft, Opt_hard,
  81         Opt_posix, Opt_noposix,
  82         Opt_cto, Opt_nocto,
  83         Opt_ac, Opt_noac,
  84         Opt_lock, Opt_nolock,
  85         Opt_udp, Opt_tcp, Opt_rdma,
  86         Opt_acl, Opt_noacl,
  87         Opt_rdirplus, Opt_nordirplus,
  88         Opt_sharecache, Opt_nosharecache,
  89         Opt_resvport, Opt_noresvport,
  90         Opt_fscache, Opt_nofscache,
  91
  92         /* Mount options that take integer arguments */
  93         Opt_port,
  94         Opt_rsize, Opt_wsize, Opt_bsize,
  95         Opt_timeo, Opt_retrans,
  96         Opt_acregmin, Opt_acregmax,
  97         Opt_acdirmin, Opt_acdirmax,
  98         Opt_actimeo,
  99         Opt_namelen,
 100         Opt_mountport,
 101         Opt_mountvers,
 102         Opt_minorversion,
 103
 104         /* Mount options that take string arguments */
 105         Opt_nfsvers,
 106         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 107         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 108         Opt_lookupcache,
 109         Opt_fscache_uniq,
 110         Opt_local_lock,
 111
 112         /* Special mount options */
 113         Opt_userspace, Opt_deprecated, Opt_sloppy,
 114
 115         Opt_err
 116 };
 117
 118 static const match_table_t nfs_mount_option_tokens = {
 119         { Opt_userspace, "bg" },
 120         { Opt_userspace, "fg" },
 121         { Opt_userspace, "retry=%s" },
 122
 123         { Opt_sloppy, "sloppy" },
 124
 125         { Opt_soft, "soft" },
 126         { Opt_hard, "hard" },
 127         { Opt_deprecated, "intr" },
 128         { Opt_deprecated, "nointr" },
 129         { Opt_posix, "posix" },
 130         { Opt_noposix, "noposix" },
 131         { Opt_cto, "cto" },
 132         { Opt_nocto, "nocto" },
 133         { Opt_ac, "ac" },
 134         { Opt_noac, "noac" },
 135         { Opt_lock, "lock" },
 136         { Opt_nolock, "nolock" },
 137         { Opt_udp, "udp" },
 138         { Opt_tcp, "tcp" },
 139         { Opt_rdma, "rdma" },
 140         { Opt_acl, "acl" },
 141         { Opt_noacl, "noacl" },
 142         { Opt_rdirplus, "rdirplus" },
 143         { Opt_nordirplus, "nordirplus" },
 144         { Opt_sharecache, "sharecache" },
 145         { Opt_nosharecache, "nosharecache" },
 146         { Opt_resvport, "resvport" },
 147         { Opt_noresvport, "noresvport" },
 148         { Opt_fscache, "fsc" },
 149         { Opt_nofscache, "nofsc" },
 150
 151         { Opt_port, "port=%s" },
 152         { Opt_rsize, "rsize=%s" },
 153         { Opt_wsize, "wsize=%s" },
 154         { Opt_bsize, "bsize=%s" },
 155         { Opt_timeo, "timeo=%s" },
 156         { Opt_retrans, "retrans=%s" },
 157         { Opt_acregmin, "acregmin=%s" },
 158         { Opt_acregmax, "acregmax=%s" },
 159         { Opt_acdirmin, "acdirmin=%s" },
 160         { Opt_acdirmax, "acdirmax=%s" },
 161         { Opt_actimeo, "actimeo=%s" },
 162         { Opt_namelen, "namlen=%s" },
 163         { Opt_mountport, "mountport=%s" },
 164         { Opt_mountvers, "mountvers=%s" },
 165         { Opt_minorversion, "minorversion=%s" },
 166
 167         { Opt_nfsvers, "nfsvers=%s" },
 168         { Opt_nfsvers, "vers=%s" },
 169
 170         { Opt_sec, "sec=%s" },
 171         { Opt_proto, "proto=%s" },
 172         { Opt_mountproto, "mountproto=%s" },
 173         { Opt_addr, "addr=%s" },
 174         { Opt_clientaddr, "clientaddr=%s" },
 175         { Opt_mounthost, "mounthost=%s" },
 176         { Opt_mountaddr, "mountaddr=%s" },
 177
 178         { Opt_lookupcache, "lookupcache=%s" },
 179         { Opt_fscache_uniq, "fsc=%s" },
 180         { Opt_local_lock, "local_lock=%s" },
 181
 182         /* The following needs to be listed after all other options */
 183         { Opt_nfsvers, "v%s" },
 184
 185         { Opt_err, NULL }
 186 };
 187
 188 enum {
 189         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 190
 191         Opt_xprt_err
 192 };
 193
 194 static const match_table_t nfs_xprt_protocol_tokens = {
 195         { Opt_xprt_udp, "udp" },
 196         { Opt_xprt_udp6, "udp6" },
 197         { Opt_xprt_tcp, "tcp" },
 198         { Opt_xprt_tcp6, "tcp6" },
 199         { Opt_xprt_rdma, "rdma" },
 200
 201         { Opt_xprt_err, NULL }
 202 };
 203
 204 enum {
 205         Opt_sec_none, Opt_sec_sys,
 206         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 207         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 208         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 209
 210         Opt_sec_err
 211 };
 212
 213 static const match_table_t nfs_secflavor_tokens = {
 214         { Opt_sec_none, "none" },
 215         { Opt_sec_none, "null" },
 216         { Opt_sec_sys, "sys" },
 217
 218         { Opt_sec_krb5, "krb5" },
 219         { Opt_sec_krb5i, "krb5i" },
 220         { Opt_sec_krb5p, "krb5p" },
 221
 222         { Opt_sec_lkey, "lkey" },
 223         { Opt_sec_lkeyi, "lkeyi" },
 224         { Opt_sec_lkeyp, "lkeyp" },
 225
 226         { Opt_sec_spkm, "spkm3" },
 227         { Opt_sec_spkmi, "spkm3i" },
 228         { Opt_sec_spkmp, "spkm3p" },
 229
 230         { Opt_sec_err, NULL }
 231 };
 232
 233 enum {
 234         Opt_lookupcache_all, Opt_lookupcache_positive,
 235         Opt_lookupcache_none,
 236
 237         Opt_lookupcache_err
 238 };
 239
 240 static match_table_t nfs_lookupcache_tokens = {
 241         { Opt_lookupcache_all, "all" },
 242         { Opt_lookupcache_positive, "pos" },
 243         { Opt_lookupcache_positive, "positive" },
 244         { Opt_lookupcache_none, "none" },
 245
 246         { Opt_lookupcache_err, NULL }
 247 };
 248
 249 enum {
 250         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 251         Opt_local_lock_none,
 252
 253         Opt_local_lock_err
 254 };
 255
 256 static match_table_t nfs_local_lock_tokens = {
 257         { Opt_local_lock_all, "all" },
 258         { Opt_local_lock_flock, "flock" },
 259         { Opt_local_lock_posix, "posix" },
 260         { Opt_local_lock_none, "none" },
 261
 262         { Opt_local_lock_err, NULL }
 263 };
 264
 265 enum {
 266         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 267         Opt_vers_4_1,
 268
 269         Opt_vers_err
 270 };
 271
 272 static match_table_t nfs_vers_tokens = {
 273         { Opt_vers_2, "2" },
 274         { Opt_vers_3, "3" },
 275         { Opt_vers_4, "4" },
 276         { Opt_vers_4_0, "4.0" },
 277         { Opt_vers_4_1, "4.1" },
 278
 279         { Opt_vers_err, NULL }
 280 };
 281
 282 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 283                 int flags, const char *dev_name, void *raw_data);
 284
 285 struct file_system_type nfs_fs_type = {
 286         .owner          = THIS_MODULE,
 287         .name           = "nfs",
 288         .mount          = nfs_fs_mount,
 289         .kill_sb        = nfs_kill_super,
 290         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 291 };
 292 EXPORT_SYMBOL_GPL(nfs_fs_type);
 293
 294 struct file_system_type nfs_xdev_fs_type = {
 295         .owner          = THIS_MODULE,
 296         .name           = "nfs",
 297         .mount          = nfs_xdev_mount,
 298         .kill_sb        = nfs_kill_super,
 299         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 300 };
 301
 302 const struct super_operations nfs_sops = {
 303         .alloc_inode    = nfs_alloc_inode,
 304         .destroy_inode  = nfs_destroy_inode,
 305         .write_inode    = nfs_write_inode,
 306         .put_super      = nfs_put_super,
 307         .statfs         = nfs_statfs,
 308         .evict_inode    = nfs_evict_inode,
 309         .umount_begin   = nfs_umount_begin,
 310         .show_options   = nfs_show_options,
 311         .show_devname   = nfs_show_devname,
 312         .show_path      = nfs_show_path,
 313         .show_stats     = nfs_show_stats,
 314         .remount_fs     = nfs_remount,
 315 };
 316 EXPORT_SYMBOL_GPL(nfs_sops);
 317
 318 #if IS_ENABLED(CONFIG_NFS_V4)
 319 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 320 static int nfs4_validate_mount_data(void *options,
 321         struct nfs_parsed_mount_data *args, const char *dev_name);
 322
 323 struct file_system_type nfs4_fs_type = {
 324         .owner          = THIS_MODULE,
 325         .name           = "nfs4",
 326         .mount          = nfs_fs_mount,
 327         .kill_sb        = nfs_kill_super,
 328         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 329 };
 330 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 331
 332 static int __init register_nfs4_fs(void)
 333 {
 334         return register_filesystem(&nfs4_fs_type);
 335 }
 336
 337 static void unregister_nfs4_fs(void)
 338 {
 339         unregister_filesystem(&nfs4_fs_type);
 340 }
 341 #else
 342 static int __init register_nfs4_fs(void)
 343 {
 344         return 0;
 345 }
 346
 347 static void unregister_nfs4_fs(void)
 348 {
 349 }
 350 #endif
 351
 352 static struct shrinker acl_shrinker = {
 353         .shrink         = nfs_access_cache_shrinker,
 354         .seeks          = DEFAULT_SEEKS,
 355 };
 356
 357 /*
 358  * Register the NFS filesystems
 359  */
 360 int __init register_nfs_fs(void)
 361 {
 362         int ret;
 363
 364         ret = register_filesystem(&nfs_fs_type);
 365         if (ret < 0)
 366                 goto error_0;
 367
 368         ret = register_nfs4_fs();
 369         if (ret < 0)
 370                 goto error_1;
 371
 372         ret = nfs_register_sysctl();
 373         if (ret < 0)
 374                 goto error_2;
 375         register_shrinker(&acl_shrinker);
 376         return 0;
 377
 378 error_2:
 379         unregister_nfs4_fs();
 380 error_1:
 381         unregister_filesystem(&nfs_fs_type);
 382 error_0:
 383         return ret;
 384 }
 385
 386 /*
 387  * Unregister the NFS filesystems
 388  */
 389 void __exit unregister_nfs_fs(void)
 390 {
 391         unregister_shrinker(&acl_shrinker);
 392         nfs_unregister_sysctl();
 393         unregister_nfs4_fs();
 394         unregister_filesystem(&nfs_fs_type);
 395 }
 396
 397 void nfs_sb_active(struct super_block *sb)
 398 {
 399         struct nfs_server *server = NFS_SB(sb);
 400
 401         if (atomic_inc_return(&server->active) == 1)
 402                 atomic_inc(&sb->s_active);
 403 }
 404 EXPORT_SYMBOL_GPL(nfs_sb_active);
 405
 406 void nfs_sb_deactive(struct super_block *sb)
 407 {
 408         struct nfs_server *server = NFS_SB(sb);
 409
 410         if (atomic_dec_and_test(&server->active))
 411                 deactivate_super(sb);
 412 }
 413 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 414
 415 /*
 416  * Deliver file system statistics to userspace
 417  */
 418 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 419 {
 420         struct nfs_server *server = NFS_SB(dentry->d_sb);
 421         unsigned char blockbits;
 422         unsigned long blockres;
 423         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 424         struct nfs_fsstat res;
 425         int error = -ENOMEM;
 426
 427         res.fattr = nfs_alloc_fattr();
 428         if (res.fattr == NULL)
 429                 goto out_err;
 430
 431         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 432         if (unlikely(error == -ESTALE)) {
 433                 struct dentry *pd_dentry;
 434
 435                 pd_dentry = dget_parent(dentry);
 436                 if (pd_dentry != NULL) {
 437                         nfs_zap_caches(pd_dentry->d_inode);
 438                         dput(pd_dentry);
 439                 }
 440         }
 441         nfs_free_fattr(res.fattr);
 442         if (error < 0)
 443                 goto out_err;
 444
 445         buf->f_type = NFS_SUPER_MAGIC;
 446
 447         /*
 448          * Current versions of glibc do not correctly handle the
 449          * case where f_frsize != f_bsize.  Eventually we want to
 450          * report the value of wtmult in this field.
 451          */
 452         buf->f_frsize = dentry->d_sb->s_blocksize;
 453
 454         /*
 455          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 456          * are reported in units of f_frsize.  Linux hasn't had
 457          * an f_frsize field in its statfs struct until recently,
 458          * thus historically Linux's sys_statfs reports these
 459          * fields in units of f_bsize.
 460          */
 461         buf->f_bsize = dentry->d_sb->s_blocksize;
 462         blockbits = dentry->d_sb->s_blocksize_bits;
 463         blockres = (1 << blockbits) - 1;
 464         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 465         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 466         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 467
 468         buf->f_files = res.tfiles;
 469         buf->f_ffree = res.afiles;
 470
 471         buf->f_namelen = server->namelen;
 472
 473         return 0;
 474
 475  out_err:
 476         dprintk("%s: statfs error = %d\n", __func__, -error);
 477         return error;
 478 }
 479 EXPORT_SYMBOL_GPL(nfs_statfs);
 480
 481 /*
 482  * Map the security flavour number to a name
 483  */
 484 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 485 {
 486         static const struct {
 487                 rpc_authflavor_t flavour;
 488                 const char *str;
 489         } sec_flavours[] = {
 490                 { RPC_AUTH_NULL, "null" },
 491                 { RPC_AUTH_UNIX, "sys" },
 492                 { RPC_AUTH_GSS_KRB5, "krb5" },
 493                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 494                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 495                 { RPC_AUTH_GSS_LKEY, "lkey" },
 496                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 497                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 498                 { RPC_AUTH_GSS_SPKM, "spkm" },
 499                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 500                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 501                 { UINT_MAX, "unknown" }
 502         };
 503         int i;
 504
 505         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 506                 if (sec_flavours[i].flavour == flavour)
 507                         break;
 508         }
 509         return sec_flavours[i].str;
 510 }
 511
 512 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 513                                   int showdefaults)
 514 {
 515         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 516
 517         seq_printf(m, ",mountproto=");
 518         switch (sap->sa_family) {
 519         case AF_INET:
 520                 switch (nfss->mountd_protocol) {
 521                 case IPPROTO_UDP:
 522                         seq_printf(m, RPCBIND_NETID_UDP);
 523                         break;
 524                 case IPPROTO_TCP:
 525                         seq_printf(m, RPCBIND_NETID_TCP);
 526                         break;
 527                 default:
 528                         if (showdefaults)
 529                                 seq_printf(m, "auto");
 530                 }
 531                 break;
 532         case AF_INET6:
 533                 switch (nfss->mountd_protocol) {
 534                 case IPPROTO_UDP:
 535                         seq_printf(m, RPCBIND_NETID_UDP6);
 536                         break;
 537                 case IPPROTO_TCP:
 538                         seq_printf(m, RPCBIND_NETID_TCP6);
 539                         break;
 540                 default:
 541                         if (showdefaults)
 542                                 seq_printf(m, "auto");
 543                 }
 544                 break;
 545         default:
 546                 if (showdefaults)
 547                         seq_printf(m, "auto");
 548         }
 549 }
 550
 551 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 552                                     int showdefaults)
 553 {
 554         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 555
 556         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 557                 return;
 558
 559         switch (sap->sa_family) {
 560         case AF_INET: {
 561                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 562                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 563                 break;
 564         }
 565         case AF_INET6: {
 566                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 567                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 568                 break;
 569         }
 570         default:
 571                 if (showdefaults)
 572                         seq_printf(m, ",mountaddr=unspecified");
 573         }
 574
 575         if (nfss->mountd_version || showdefaults)
 576                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 577         if ((nfss->mountd_port &&
 578                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 579                 showdefaults)
 580                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 581
 582         nfs_show_mountd_netid(m, nfss, showdefaults);
 583 }
 584
 585 #if IS_ENABLED(CONFIG_NFS_V4)
 586 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 587                                     int showdefaults)
 588 {
 589         struct nfs_client *clp = nfss->nfs_client;
 590
 591         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 592 }
 593 #else
 594 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 595                                     int showdefaults)
 596 {
 597 }
 598 #endif
 599
 600 static void nfs_show_nfs_version(struct seq_file *m,
 601                 unsigned int version,
 602                 unsigned int minorversion)
 603 {
 604         seq_printf(m, ",vers=%u", version);
 605         if (version == 4)
 606                 seq_printf(m, ".%u", minorversion);
 607 }
 608
 609 /*
 610  * Describe the mount options in force on this server representation
 611  */
 612 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 613                                    int showdefaults)
 614 {
 615         static const struct proc_nfs_info {
 616                 int flag;
 617                 const char *str;
 618                 const char *nostr;
 619         } nfs_info[] = {
 620                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 621                 { NFS_MOUNT_POSIX, ",posix", "" },
 622                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 623                 { NFS_MOUNT_NOAC, ",noac", "" },
 624                 { NFS_MOUNT_NONLM, ",nolock", "" },
 625                 { NFS_MOUNT_NOACL, ",noacl", "" },
 626                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 627                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 628                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 629                 { 0, NULL, NULL }
 630         };
 631         const struct proc_nfs_info *nfs_infop;
 632         struct nfs_client *clp = nfss->nfs_client;
 633         u32 version = clp->rpc_ops->version;
 634         int local_flock, local_fcntl;
 635
 636         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 637         seq_printf(m, ",rsize=%u", nfss->rsize);
 638         seq_printf(m, ",wsize=%u", nfss->wsize);
 639         if (nfss->bsize != 0)
 640                 seq_printf(m, ",bsize=%u", nfss->bsize);
 641         seq_printf(m, ",namlen=%u", nfss->namelen);
 642         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 643                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 644         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 645                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 646         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 647                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 648         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 649                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 650         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 651                 if (nfss->flags & nfs_infop->flag)
 652                         seq_puts(m, nfs_infop->str);
 653                 else
 654                         seq_puts(m, nfs_infop->nostr);
 655         }
 656         rcu_read_lock();
 657         seq_printf(m, ",proto=%s",
 658                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 659         rcu_read_unlock();
 660         if (version == 4) {
 661                 if (nfss->port != NFS_PORT)
 662                         seq_printf(m, ",port=%u", nfss->port);
 663         } else
 664                 if (nfss->port)
 665                         seq_printf(m, ",port=%u", nfss->port);
 666
 667         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 668         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 669         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 670
 671         if (version != 4)
 672                 nfs_show_mountd_options(m, nfss, showdefaults);
 673         else
 674                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 675
 676         if (nfss->options & NFS_OPTION_FSCACHE)
 677                 seq_printf(m, ",fsc");
 678
 679         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 680                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 681                         seq_printf(m, ",lookupcache=none");
 682                 else
 683                         seq_printf(m, ",lookupcache=pos");
 684         }
 685
 686         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 687         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 688
 689         if (!local_flock && !local_fcntl)
 690                 seq_printf(m, ",local_lock=none");
 691         else if (local_flock && local_fcntl)
 692                 seq_printf(m, ",local_lock=all");
 693         else if (local_flock)
 694                 seq_printf(m, ",local_lock=flock");
 695         else
 696                 seq_printf(m, ",local_lock=posix");
 697 }
 698
 699 /*
 700  * Describe the mount options on this VFS mountpoint
 701  */
 702 int nfs_show_options(struct seq_file *m, struct dentry *root)
 703 {
 704         struct nfs_server *nfss = NFS_SB(root->d_sb);
 705
 706         nfs_show_mount_options(m, nfss, 0);
 707
 708         rcu_read_lock();
 709         seq_printf(m, ",addr=%s",
 710                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 711                                                         RPC_DISPLAY_ADDR));
 712         rcu_read_unlock();
 713
 714         return 0;
 715 }
 716 EXPORT_SYMBOL_GPL(nfs_show_options);
 717
 718 #if IS_ENABLED(CONFIG_NFS_V4)
 719 #ifdef CONFIG_NFS_V4_1
 720 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 721 {
 722         if (nfs4_has_session(server->nfs_client))
 723                 seq_printf(m, ",sessions");
 724 }
 725 #else
 726 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 727 #endif
 728 #endif
 729
 730 #ifdef CONFIG_NFS_V4_1
 731 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 732 {
 733         seq_printf(m, ",pnfs=");
 734         if (server->pnfs_curr_ld)
 735                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 736         else
 737                 seq_printf(m, "not configured");
 738 }
 739
 740 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 741 {
 742         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 743                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 744                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 745                            "date='%llu,%u'",
 746                            impl_id->name, impl_id->domain,
 747                            impl_id->date.seconds, impl_id->date.nseconds);
 748         }
 749 }
 750 #else
 751 #if IS_ENABLED(CONFIG_NFS_V4)
 752 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 753 {
 754 }
 755 #endif
 756 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 757 {
 758 }
 759 #endif
 760
 761 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 762 {
 763         char *page = (char *) __get_free_page(GFP_KERNEL);
 764         char *devname, *dummy;
 765         int err = 0;
 766         if (!page)
 767                 return -ENOMEM;
 768         devname = nfs_path(&dummy, root, page, PAGE_SIZE);
 769         if (IS_ERR(devname))
 770                 err = PTR_ERR(devname);
 771         else
 772                 seq_escape(m, devname, " \t\n\\");
 773         free_page((unsigned long)page);
 774         return err;
 775 }
 776 EXPORT_SYMBOL_GPL(nfs_show_devname);
 777
 778 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 779 {
 780         seq_puts(m, "/");
 781         return 0;
 782 }
 783 EXPORT_SYMBOL_GPL(nfs_show_path);
 784
 785 /*
 786  * Present statistical information for this VFS mountpoint
 787  */
 788 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 789 {
 790         int i, cpu;
 791         struct nfs_server *nfss = NFS_SB(root->d_sb);
 792         struct rpc_auth *auth = nfss->client->cl_auth;
 793         struct nfs_iostats totals = { };
 794
 795         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 796
 797         /*
 798          * Display all mount option settings
 799          */
 800         seq_printf(m, "\n\topts:\t");
 801         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 802         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 803         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 804         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 805         nfs_show_mount_options(m, nfss, 1);
 806
 807         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 808
 809         show_implementation_id(m, nfss);
 810
 811         seq_printf(m, "\n\tcaps:\t");
 812         seq_printf(m, "caps=0x%x", nfss->caps);
 813         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 814         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 815         seq_printf(m, ",bsize=%u", nfss->bsize);
 816         seq_printf(m, ",namlen=%u", nfss->namelen);
 817
 818 #if IS_ENABLED(CONFIG_NFS_V4)
 819         if (nfss->nfs_client->rpc_ops->version == 4) {
 820                 seq_printf(m, "\n\tnfsv4:\t");
 821                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 822                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 823                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 824                 show_sessions(m, nfss);
 825                 show_pnfs(m, nfss);
 826         }
 827 #endif
 828
 829         /*
 830          * Display security flavor in effect for this mount
 831          */
 832         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 833         if (auth->au_flavor)
 834                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 835
 836         /*
 837          * Display superblock I/O counters
 838          */
 839         for_each_possible_cpu(cpu) {
 840                 struct nfs_iostats *stats;
 841
 842                 preempt_disable();
 843                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 844
 845                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 846                         totals.events[i] += stats->events[i];
 847                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 848                         totals.bytes[i] += stats->bytes[i];
 849 #ifdef CONFIG_NFS_FSCACHE
 850                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 851                         totals.fscache[i] += stats->fscache[i];
 852 #endif
 853
 854                 preempt_enable();
 855         }
 856
 857         seq_printf(m, "\n\tevents:\t");
 858         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 859                 seq_printf(m, "%lu ", totals.events[i]);
 860         seq_printf(m, "\n\tbytes:\t");
 861         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 862                 seq_printf(m, "%Lu ", totals.bytes[i]);
 863 #ifdef CONFIG_NFS_FSCACHE
 864         if (nfss->options & NFS_OPTION_FSCACHE) {
 865                 seq_printf(m, "\n\tfsc:\t");
 866                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 867                         seq_printf(m, "%Lu ", totals.bytes[i]);
 868         }
 869 #endif
 870         seq_printf(m, "\n");
 871
 872         rpc_print_iostats(m, nfss->client);
 873
 874         return 0;
 875 }
 876 EXPORT_SYMBOL_GPL(nfs_show_stats);
 877
 878 /*
 879  * Begin unmount by attempting to remove all automounted mountpoints we added
 880  * in response to xdev traversals and referrals
 881  */
 882 void nfs_umount_begin(struct super_block *sb)
 883 {
 884         struct nfs_server *server;
 885         struct rpc_clnt *rpc;
 886
 887         server = NFS_SB(sb);
 888         /* -EIO all pending I/O */
 889         rpc = server->client_acl;
 890         if (!IS_ERR(rpc))
 891                 rpc_killall_tasks(rpc);
 892         rpc = server->client;
 893         if (!IS_ERR(rpc))
 894                 rpc_killall_tasks(rpc);
 895 }
 896 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 897
 898 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 899 {
 900         struct nfs_parsed_mount_data *data;
 901
 902         data = kzalloc(sizeof(*data), GFP_KERNEL);
 903         if (data) {
 904                 data->acregmin          = NFS_DEF_ACREGMIN;
 905                 data->acregmax          = NFS_DEF_ACREGMAX;
 906                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 907                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 908                 data->mount_server.port = NFS_UNSPEC_PORT;
 909                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 910                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 911                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 912                 data->auth_flavor_len   = 1;
 913                 data->minorversion      = 0;
 914                 data->need_mount        = true;
 915                 data->net               = current->nsproxy->net_ns;
 916                 security_init_mnt_opts(&data->lsm_opts);
 917         }
 918         return data;
 919 }
 920
 921 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 922 {
 923         if (data) {
 924                 kfree(data->client_address);
 925                 kfree(data->mount_server.hostname);
 926                 kfree(data->nfs_server.export_path);
 927                 kfree(data->nfs_server.hostname);
 928                 kfree(data->fscache_uniq);
 929                 security_free_mnt_opts(&data->lsm_opts);
 930                 kfree(data);
 931         }
 932 }
 933
 934 /*
 935  * Sanity-check a server address provided by the mount command.
 936  *
 937  * Address family must be initialized, and address must not be
 938  * the ANY address for that family.
 939  */
 940 static int nfs_verify_server_address(struct sockaddr *addr)
 941 {
 942         switch (addr->sa_family) {
 943         case AF_INET: {
 944                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 945                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 946         }
 947         case AF_INET6: {
 948                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 949                 return !ipv6_addr_any(sa);
 950         }
 951         }
 952
 953         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 954         return 0;
 955 }
 956
 957 /*
 958  * Select between a default port value and a user-specified port value.
 959  * If a zero value is set, then autobind will be used.
 960  */
 961 static void nfs_set_port(struct sockaddr *sap, int *port,
 962                                  const unsigned short default_port)
 963 {
 964         if (*port == NFS_UNSPEC_PORT)
 965                 *port = default_port;
 966
 967         rpc_set_port(sap, *port);
 968 }
 969
 970 /*
 971  * Sanity check the NFS transport protocol.
 972  *
 973  */
 974 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 975 {
 976         switch (mnt->nfs_server.protocol) {
 977         case XPRT_TRANSPORT_UDP:
 978         case XPRT_TRANSPORT_TCP:
 979         case XPRT_TRANSPORT_RDMA:
 980                 break;
 981         default:
 982                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 983         }
 984 }
 985
 986 /*
 987  * For text based NFSv2/v3 mounts, the mount protocol transport default
 988  * settings should depend upon the specified NFS transport.
 989  */
 990 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 991 {
 992         nfs_validate_transport_protocol(mnt);
 993
 994         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 995             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
 996                         return;
 997         switch (mnt->nfs_server.protocol) {
 998         case XPRT_TRANSPORT_UDP:
 999                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1000                 break;
1001         case XPRT_TRANSPORT_TCP:
1002         case XPRT_TRANSPORT_RDMA:
1003                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1004         }
1005 }
1006
1007 /*
1008  * Parse the value of the 'sec=' option.
1009  */
1010 static int nfs_parse_security_flavors(char *value,
1011                                       struct nfs_parsed_mount_data *mnt)
1012 {
1013         substring_t args[MAX_OPT_ARGS];
1014
1015         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1016
1017         switch (match_token(value, nfs_secflavor_tokens, args)) {
1018         case Opt_sec_none:
1019                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1020                 break;
1021         case Opt_sec_sys:
1022                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1023                 break;
1024         case Opt_sec_krb5:
1025                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1026                 break;
1027         case Opt_sec_krb5i:
1028                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1029                 break;
1030         case Opt_sec_krb5p:
1031                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1032                 break;
1033         case Opt_sec_lkey:
1034                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1035                 break;
1036         case Opt_sec_lkeyi:
1037                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1038                 break;
1039         case Opt_sec_lkeyp:
1040                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1041                 break;
1042         case Opt_sec_spkm:
1043                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1044                 break;
1045         case Opt_sec_spkmi:
1046                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1047                 break;
1048         case Opt_sec_spkmp:
1049                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1050                 break;
1051         default:
1052                 return 0;
1053         }
1054
1055         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1056         mnt->auth_flavor_len = 1;
1057         return 1;
1058 }
1059
1060 static int nfs_parse_version_string(char *string,
1061                 struct nfs_parsed_mount_data *mnt,
1062                 substring_t *args)
1063 {
1064         mnt->flags &= ~NFS_MOUNT_VER3;
1065         switch (match_token(string, nfs_vers_tokens, args)) {
1066         case Opt_vers_2:
1067                 mnt->version = 2;
1068                 break;
1069         case Opt_vers_3:
1070                 mnt->flags |= NFS_MOUNT_VER3;
1071                 mnt->version = 3;
1072                 break;
1073         case Opt_vers_4:
1074                 /* Backward compatibility option. In future,
1075                  * the mount program should always supply
1076                  * a NFSv4 minor version number.
1077                  */
1078                 mnt->version = 4;
1079                 break;
1080         case Opt_vers_4_0:
1081                 mnt->version = 4;
1082                 mnt->minorversion = 0;
1083                 break;
1084         case Opt_vers_4_1:
1085                 mnt->version = 4;
1086                 mnt->minorversion = 1;
1087                 break;
1088         default:
1089                 return 0;
1090         }
1091         return 1;
1092 }
1093
1094 static int nfs_get_option_str(substring_t args[], char **option)
1095 {
1096         kfree(*option);
1097         *option = match_strdup(args);
1098         return !option;
1099 }
1100
1101 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1102 {
1103         int rc;
1104         char *string;
1105
1106         string = match_strdup(args);
1107         if (string == NULL)
1108                 return -ENOMEM;
1109         rc = strict_strtoul(string, 10, option);
1110         kfree(string);
1111
1112         return rc;
1113 }
1114
1115 /*
1116  * Error-check and convert a string of mount options from user space into
1117  * a data structure.  The whole mount string is processed; bad options are
1118  * skipped as they are encountered.  If there were no errors, return 1;
1119  * otherwise return 0 (zero).
1120  */
1121 static int nfs_parse_mount_options(char *raw,
1122                                    struct nfs_parsed_mount_data *mnt)
1123 {
1124         char *p, *string, *secdata;
1125         int rc, sloppy = 0, invalid_option = 0;
1126         unsigned short protofamily = AF_UNSPEC;
1127         unsigned short mountfamily = AF_UNSPEC;
1128
1129         if (!raw) {
1130                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1131                 return 1;
1132         }
1133         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1134
1135         secdata = alloc_secdata();
1136         if (!secdata)
1137                 goto out_nomem;
1138
1139         rc = security_sb_copy_data(raw, secdata);
1140         if (rc)
1141                 goto out_security_failure;
1142
1143         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1144         if (rc)
1145                 goto out_security_failure;
1146
1147         free_secdata(secdata);
1148
1149         while ((p = strsep(&raw, ",")) != NULL) {
1150                 substring_t args[MAX_OPT_ARGS];
1151                 unsigned long option;
1152                 int token;
1153
1154                 if (!*p)
1155                         continue;
1156
1157                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1158
1159                 token = match_token(p, nfs_mount_option_tokens, args);
1160                 switch (token) {
1161
1162                 /*
1163                  * boolean options:  foo/nofoo
1164                  */
1165                 case Opt_soft:
1166                         mnt->flags |= NFS_MOUNT_SOFT;
1167                         break;
1168                 case Opt_hard:
1169                         mnt->flags &= ~NFS_MOUNT_SOFT;
1170                         break;
1171                 case Opt_posix:
1172                         mnt->flags |= NFS_MOUNT_POSIX;
1173                         break;
1174                 case Opt_noposix:
1175                         mnt->flags &= ~NFS_MOUNT_POSIX;
1176                         break;
1177                 case Opt_cto:
1178                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1179                         break;
1180                 case Opt_nocto:
1181                         mnt->flags |= NFS_MOUNT_NOCTO;
1182                         break;
1183                 case Opt_ac:
1184                         mnt->flags &= ~NFS_MOUNT_NOAC;
1185                         break;
1186                 case Opt_noac:
1187                         mnt->flags |= NFS_MOUNT_NOAC;
1188                         break;
1189                 case Opt_lock:
1190                         mnt->flags &= ~NFS_MOUNT_NONLM;
1191                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1192                                         NFS_MOUNT_LOCAL_FCNTL);
1193                         break;
1194                 case Opt_nolock:
1195                         mnt->flags |= NFS_MOUNT_NONLM;
1196                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1197                                        NFS_MOUNT_LOCAL_FCNTL);
1198                         break;
1199                 case Opt_udp:
1200                         mnt->flags &= ~NFS_MOUNT_TCP;
1201                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1202                         break;
1203                 case Opt_tcp:
1204                         mnt->flags |= NFS_MOUNT_TCP;
1205                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1206                         break;
1207                 case Opt_rdma:
1208                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1209                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1210                         xprt_load_transport(p);
1211                         break;
1212                 case Opt_acl:
1213                         mnt->flags &= ~NFS_MOUNT_NOACL;
1214                         break;
1215                 case Opt_noacl:
1216                         mnt->flags |= NFS_MOUNT_NOACL;
1217                         break;
1218                 case Opt_rdirplus:
1219                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1220                         break;
1221                 case Opt_nordirplus:
1222                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1223                         break;
1224                 case Opt_sharecache:
1225                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1226                         break;
1227                 case Opt_nosharecache:
1228                         mnt->flags |= NFS_MOUNT_UNSHARED;
1229                         break;
1230                 case Opt_resvport:
1231                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1232                         break;
1233                 case Opt_noresvport:
1234                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1235                         break;
1236                 case Opt_fscache:
1237                         mnt->options |= NFS_OPTION_FSCACHE;
1238                         kfree(mnt->fscache_uniq);
1239                         mnt->fscache_uniq = NULL;
1240                         break;
1241                 case Opt_nofscache:
1242                         mnt->options &= ~NFS_OPTION_FSCACHE;
1243                         kfree(mnt->fscache_uniq);
1244                         mnt->fscache_uniq = NULL;
1245                         break;
1246
1247                 /*
1248                  * options that take numeric values
1249                  */
1250                 case Opt_port:
1251                         if (nfs_get_option_ul(args, &option) ||
1252                             option > USHRT_MAX)
1253                                 goto out_invalid_value;
1254                         mnt->nfs_server.port = option;
1255                         break;
1256                 case Opt_rsize:
1257                         if (nfs_get_option_ul(args, &option))
1258                                 goto out_invalid_value;
1259                         mnt->rsize = option;
1260                         break;
1261                 case Opt_wsize:
1262                         if (nfs_get_option_ul(args, &option))
1263                                 goto out_invalid_value;
1264                         mnt->wsize = option;
1265                         break;
1266                 case Opt_bsize:
1267                         if (nfs_get_option_ul(args, &option))
1268                                 goto out_invalid_value;
1269                         mnt->bsize = option;
1270                         break;
1271                 case Opt_timeo:
1272                         if (nfs_get_option_ul(args, &option) || option == 0)
1273                                 goto out_invalid_value;
1274                         mnt->timeo = option;
1275                         break;
1276                 case Opt_retrans:
1277                         if (nfs_get_option_ul(args, &option) || option == 0)
1278                                 goto out_invalid_value;
1279                         mnt->retrans = option;
1280                         break;
1281                 case Opt_acregmin:
1282                         if (nfs_get_option_ul(args, &option))
1283                                 goto out_invalid_value;
1284                         mnt->acregmin = option;
1285                         break;
1286                 case Opt_acregmax:
1287                         if (nfs_get_option_ul(args, &option))
1288                                 goto out_invalid_value;
1289                         mnt->acregmax = option;
1290                         break;
1291                 case Opt_acdirmin:
1292                         if (nfs_get_option_ul(args, &option))
1293                                 goto out_invalid_value;
1294                         mnt->acdirmin = option;
1295                         break;
1296                 case Opt_acdirmax:
1297                         if (nfs_get_option_ul(args, &option))
1298                                 goto out_invalid_value;
1299                         mnt->acdirmax = option;
1300                         break;
1301                 case Opt_actimeo:
1302                         if (nfs_get_option_ul(args, &option))
1303                                 goto out_invalid_value;
1304                         mnt->acregmin = mnt->acregmax =
1305                         mnt->acdirmin = mnt->acdirmax = option;
1306                         break;
1307                 case Opt_namelen:
1308                         if (nfs_get_option_ul(args, &option))
1309                                 goto out_invalid_value;
1310                         mnt->namlen = option;
1311                         break;
1312                 case Opt_mountport:
1313                         if (nfs_get_option_ul(args, &option) ||
1314                             option > USHRT_MAX)
1315                                 goto out_invalid_value;
1316                         mnt->mount_server.port = option;
1317                         break;
1318                 case Opt_mountvers:
1319                         if (nfs_get_option_ul(args, &option) ||
1320                             option < NFS_MNT_VERSION ||
1321                             option > NFS_MNT3_VERSION)
1322                                 goto out_invalid_value;
1323                         mnt->mount_server.version = option;
1324                         break;
1325                 case Opt_minorversion:
1326                         if (nfs_get_option_ul(args, &option))
1327                                 goto out_invalid_value;
1328                         if (option > NFS4_MAX_MINOR_VERSION)
1329                                 goto out_invalid_value;
1330                         mnt->minorversion = option;
1331                         break;
1332
1333                 /*
1334                  * options that take text values
1335                  */
1336                 case Opt_nfsvers:
1337                         string = match_strdup(args);
1338                         if (string == NULL)
1339                                 goto out_nomem;
1340                         rc = nfs_parse_version_string(string, mnt, args);
1341                         kfree(string);
1342                         if (!rc)
1343                                 goto out_invalid_value;
1344                         break;
1345                 case Opt_sec:
1346                         string = match_strdup(args);
1347                         if (string == NULL)
1348                                 goto out_nomem;
1349                         rc = nfs_parse_security_flavors(string, mnt);
1350                         kfree(string);
1351                         if (!rc) {
1352                                 dfprintk(MOUNT, "NFS:   unrecognized "
1353                                                 "security flavor\n");
1354                                 return 0;
1355                         }
1356                         break;
1357                 case Opt_proto:
1358                         string = match_strdup(args);
1359                         if (string == NULL)
1360                                 goto out_nomem;
1361                         token = match_token(string,
1362                                             nfs_xprt_protocol_tokens, args);
1363
1364                         protofamily = AF_INET;
1365                         switch (token) {
1366                         case Opt_xprt_udp6:
1367                                 protofamily = AF_INET6;
1368                         case Opt_xprt_udp:
1369                                 mnt->flags &= ~NFS_MOUNT_TCP;
1370                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1371                                 break;
1372                         case Opt_xprt_tcp6:
1373                                 protofamily = AF_INET6;
1374                         case Opt_xprt_tcp:
1375                                 mnt->flags |= NFS_MOUNT_TCP;
1376                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1377                                 break;
1378                         case Opt_xprt_rdma:
1379                                 /* vector side protocols to TCP */
1380                                 mnt->flags |= NFS_MOUNT_TCP;
1381                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1382                                 xprt_load_transport(string);
1383                                 break;
1384                         default:
1385                                 dfprintk(MOUNT, "NFS:   unrecognized "
1386                                                 "transport protocol\n");
1387                                 kfree(string);
1388                                 return 0;
1389                         }
1390                         kfree(string);
1391                         break;
1392                 case Opt_mountproto:
1393                         string = match_strdup(args);
1394                         if (string == NULL)
1395                                 goto out_nomem;
1396                         token = match_token(string,
1397                                             nfs_xprt_protocol_tokens, args);
1398                         kfree(string);
1399
1400                         mountfamily = AF_INET;
1401                         switch (token) {
1402                         case Opt_xprt_udp6:
1403                                 mountfamily = AF_INET6;
1404                         case Opt_xprt_udp:
1405                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1406                                 break;
1407                         case Opt_xprt_tcp6:
1408                                 mountfamily = AF_INET6;
1409                         case Opt_xprt_tcp:
1410                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1411                                 break;
1412                         case Opt_xprt_rdma: /* not used for side protocols */
1413                         default:
1414                                 dfprintk(MOUNT, "NFS:   unrecognized "
1415                                                 "transport protocol\n");
1416                                 return 0;
1417                         }
1418                         break;
1419                 case Opt_addr:
1420                         string = match_strdup(args);
1421                         if (string == NULL)
1422                                 goto out_nomem;
1423                         mnt->nfs_server.addrlen =
1424                                 rpc_pton(mnt->net, string, strlen(string),
1425                                         (struct sockaddr *)
1426                                         &mnt->nfs_server.address,
1427                                         sizeof(mnt->nfs_server.address));
1428                         kfree(string);
1429                         if (mnt->nfs_server.addrlen == 0)
1430                                 goto out_invalid_address;
1431                         break;
1432                 case Opt_clientaddr:
1433                         if (nfs_get_option_str(args, &mnt->client_address))
1434                                 goto out_nomem;
1435                         break;
1436                 case Opt_mounthost:
1437                         if (nfs_get_option_str(args,
1438                                                &mnt->mount_server.hostname))
1439                                 goto out_nomem;
1440                         break;
1441                 case Opt_mountaddr:
1442                         string = match_strdup(args);
1443                         if (string == NULL)
1444                                 goto out_nomem;
1445                         mnt->mount_server.addrlen =
1446                                 rpc_pton(mnt->net, string, strlen(string),
1447                                         (struct sockaddr *)
1448                                         &mnt->mount_server.address,
1449                                         sizeof(mnt->mount_server.address));
1450                         kfree(string);
1451                         if (mnt->mount_server.addrlen == 0)
1452                                 goto out_invalid_address;
1453                         break;
1454                 case Opt_lookupcache:
1455                         string = match_strdup(args);
1456                         if (string == NULL)
1457                                 goto out_nomem;
1458                         token = match_token(string,
1459                                         nfs_lookupcache_tokens, args);
1460                         kfree(string);
1461                         switch (token) {
1462                                 case Opt_lookupcache_all:
1463                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1464                                         break;
1465                                 case Opt_lookupcache_positive:
1466                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1467                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1468                                         break;
1469                                 case Opt_lookupcache_none:
1470                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1471                                         break;
1472                                 default:
1473                                         dfprintk(MOUNT, "NFS:   invalid "
1474                                                         "lookupcache argument\n");
1475                                         return 0;
1476                         };
1477                         break;
1478                 case Opt_fscache_uniq:
1479                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1480                                 goto out_nomem;
1481                         mnt->options |= NFS_OPTION_FSCACHE;
1482                         break;
1483                 case Opt_local_lock:
1484                         string = match_strdup(args);
1485                         if (string == NULL)
1486                                 goto out_nomem;
1487                         token = match_token(string, nfs_local_lock_tokens,
1488                                         args);
1489                         kfree(string);
1490                         switch (token) {
1491                         case Opt_local_lock_all:
1492                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1493                                                NFS_MOUNT_LOCAL_FCNTL);
1494                                 break;
1495                         case Opt_local_lock_flock:
1496                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1497                                 break;
1498                         case Opt_local_lock_posix:
1499                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1500                                 break;
1501                         case Opt_local_lock_none:
1502                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1503                                                 NFS_MOUNT_LOCAL_FCNTL);
1504                                 break;
1505                         default:
1506                                 dfprintk(MOUNT, "NFS:   invalid "
1507                                                 "local_lock argument\n");
1508                                 return 0;
1509                         };
1510                         break;
1511
1512                 /*
1513                  * Special options
1514                  */
1515                 case Opt_sloppy:
1516                         sloppy = 1;
1517                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1518                         break;
1519                 case Opt_userspace:
1520                 case Opt_deprecated:
1521                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1522                                         "'%s'\n", p);
1523                         break;
1524
1525                 default:
1526                         invalid_option = 1;
1527                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1528                                         "'%s'\n", p);
1529                 }
1530         }
1531
1532         if (!sloppy && invalid_option)
1533                 return 0;
1534
1535         if (mnt->minorversion && mnt->version != 4)
1536                 goto out_minorversion_mismatch;
1537
1538         /*
1539          * verify that any proto=/mountproto= options match the address
1540          * families in the addr=/mountaddr= options.
1541          */
1542         if (protofamily != AF_UNSPEC &&
1543             protofamily != mnt->nfs_server.address.ss_family)
1544                 goto out_proto_mismatch;
1545
1546         if (mountfamily != AF_UNSPEC) {
1547                 if (mnt->mount_server.addrlen) {
1548                         if (mountfamily != mnt->mount_server.address.ss_family)
1549                                 goto out_mountproto_mismatch;
1550                 } else {
1551                         if (mountfamily != mnt->nfs_server.address.ss_family)
1552                                 goto out_mountproto_mismatch;
1553                 }
1554         }
1555
1556         return 1;
1557
1558 out_mountproto_mismatch:
1559         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1560                          "option\n");
1561         return 0;
1562 out_proto_mismatch:
1563         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1564         return 0;
1565 out_invalid_address:
1566         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1567         return 0;
1568 out_invalid_value:
1569         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1570         return 0;
1571 out_minorversion_mismatch:
1572         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1573                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1574         return 0;
1575 out_nomem:
1576         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1577         return 0;
1578 out_security_failure:
1579         free_secdata(secdata);
1580         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1581         return 0;
1582 }
1583
1584 /*
1585  * Match the requested auth flavors with the list returned by
1586  * the server.  Returns zero and sets the mount's authentication
1587  * flavor on success; returns -EACCES if server does not support
1588  * the requested flavor.
1589  */
1590 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1591                              struct nfs_mount_request *request)
1592 {
1593         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1594
1595         /*
1596          * Certain releases of Linux's mountd return an empty
1597          * flavor list.  To prevent behavioral regression with
1598          * these servers (ie. rejecting mounts that used to
1599          * succeed), revert to pre-2.6.32 behavior (no checking)
1600          * if the returned flavor list is empty.
1601          */
1602         if (server_authlist_len == 0)
1603                 return 0;
1604
1605         /*
1606          * We avoid sophisticated negotiating here, as there are
1607          * plenty of cases where we can get it wrong, providing
1608          * either too little or too much security.
1609          *
1610          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1611          * flavor listed first.  However, some servers list
1612          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1613          * preferred default, in args->auth_flavors[0] if user
1614          * didn't specify sec= mount option.
1615          */
1616         for (i = 0; i < args->auth_flavor_len; i++)
1617                 for (j = 0; j < server_authlist_len; j++)
1618                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1619                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1620                                         request->auth_flavs[j]);
1621                                 args->auth_flavors[0] = request->auth_flavs[j];
1622                                 return 0;
1623                         }
1624
1625         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1626         nfs_umount(request);
1627         return -EACCES;
1628 }
1629
1630 /*
1631  * Use the remote server's MOUNT service to request the NFS file handle
1632  * corresponding to the provided path.
1633  */
1634 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1635                              struct nfs_fh *root_fh)
1636 {
1637         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1638         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1639         struct nfs_mount_request request = {
1640                 .sap            = (struct sockaddr *)
1641                                                 &args->mount_server.address,
1642                 .dirpath        = args->nfs_server.export_path,
1643                 .protocol       = args->mount_server.protocol,
1644                 .fh             = root_fh,
1645                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1646                 .auth_flav_len  = &server_authlist_len,
1647                 .auth_flavs     = server_authlist,
1648                 .net            = args->net,
1649         };
1650         int status;
1651
1652         if (args->mount_server.version == 0) {
1653                 switch (args->version) {
1654                         default:
1655                                 args->mount_server.version = NFS_MNT3_VERSION;
1656                                 break;
1657                         case 2:
1658                                 args->mount_server.version = NFS_MNT_VERSION;
1659                 }
1660         }
1661         request.version = args->mount_server.version;
1662
1663         if (args->mount_server.hostname)
1664                 request.hostname = args->mount_server.hostname;
1665         else
1666                 request.hostname = args->nfs_server.hostname;
1667
1668         /*
1669          * Construct the mount server's address.
1670          */
1671         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1672                 memcpy(request.sap, &args->nfs_server.address,
1673                        args->nfs_server.addrlen);
1674                 args->mount_server.addrlen = args->nfs_server.addrlen;
1675         }
1676         request.salen = args->mount_server.addrlen;
1677         nfs_set_port(request.sap, &args->mount_server.port, 0);
1678
1679         /*
1680          * Now ask the mount server to map our export path
1681          * to a file handle.
1682          */
1683         status = nfs_mount(&request);
1684         if (status != 0) {
1685                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1686                                 request.hostname, status);
1687                 return status;
1688         }
1689
1690         /*
1691          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1692          */
1693         if (args->mount_server.version != NFS_MNT3_VERSION)
1694                 return 0;
1695         return nfs_walk_authlist(args, &request);
1696 }
1697
1698 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1699                              struct nfs_mount_info *mount_info,
1700                              struct nfs_subversion *nfs_mod)
1701 {
1702         int status;
1703         struct nfs_server *server;
1704
1705         if (mount_info->parsed->need_mount) {
1706                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1707                 if (status)
1708                         return ERR_PTR(status);
1709         }
1710
1711         /* Get a volume representation */
1712         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1713         if (IS_ERR(server))
1714                 return ERR_CAST(server);
1715
1716         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1717 }
1718 EXPORT_SYMBOL_GPL(nfs_try_mount);
1719
1720 /*
1721  * Split "dev_name" into "hostname:export_path".
1722  *
1723  * The leftmost colon demarks the split between the server's hostname
1724  * and the export path.  If the hostname starts with a left square
1725  * bracket, then it may contain colons.
1726  *
1727  * Note: caller frees hostname and export path, even on error.
1728  */
1729 static int nfs_parse_devname(const char *dev_name,
1730                              char **hostname, size_t maxnamlen,
1731                              char **export_path, size_t maxpathlen)
1732 {
1733         size_t len;
1734         char *end;
1735
1736         /* Is the host name protected with square brakcets? */
1737         if (*dev_name == '[') {
1738                 end = strchr(++dev_name, ']');
1739                 if (end == NULL || end[1] != ':')
1740                         goto out_bad_devname;
1741
1742                 len = end - dev_name;
1743                 end++;
1744         } else {
1745                 char *comma;
1746
1747                 end = strchr(dev_name, ':');
1748                 if (end == NULL)
1749                         goto out_bad_devname;
1750                 len = end - dev_name;
1751
1752                 /* kill possible hostname list: not supported */
1753                 comma = strchr(dev_name, ',');
1754                 if (comma != NULL && comma < end)
1755                         *comma = 0;
1756         }
1757
1758         if (len > maxnamlen)
1759                 goto out_hostname;
1760
1761         /* N.B. caller will free nfs_server.hostname in all cases */
1762         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1763         if (*hostname == NULL)
1764                 goto out_nomem;
1765         len = strlen(++end);
1766         if (len > maxpathlen)
1767                 goto out_path;
1768         *export_path = kstrndup(end, len, GFP_KERNEL);
1769         if (!*export_path)
1770                 goto out_nomem;
1771
1772         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1773         return 0;
1774
1775 out_bad_devname:
1776         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1777         return -EINVAL;
1778
1779 out_nomem:
1780         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1781         return -ENOMEM;
1782
1783 out_hostname:
1784         dfprintk(MOUNT, "NFS: server hostname too long\n");
1785         return -ENAMETOOLONG;
1786
1787 out_path:
1788         dfprintk(MOUNT, "NFS: export pathname too long\n");
1789         return -ENAMETOOLONG;
1790 }
1791
1792 /*
1793  * Validate the NFS2/NFS3 mount data
1794  * - fills in the mount root filehandle
1795  *
1796  * For option strings, user space handles the following behaviors:
1797  *
1798  * + DNS: mapping server host name to IP address ("addr=" option)
1799  *
1800  * + failure mode: how to behave if a mount request can't be handled
1801  *   immediately ("fg/bg" option)
1802  *
1803  * + retry: how often to retry a mount request ("retry=" option)
1804  *
1805  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1806  *   mountproto=tcp after mountproto=udp, and so on
1807  */
1808 static int nfs23_validate_mount_data(void *options,
1809                                      struct nfs_parsed_mount_data *args,
1810                                      struct nfs_fh *mntfh,
1811                                      const char *dev_name)
1812 {
1813         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1814         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1815
1816         if (data == NULL)
1817                 goto out_no_data;
1818
1819         args->version = NFS_DEFAULT_VERSION;
1820         switch (data->version) {
1821         case 1:
1822                 data->namlen = 0;
1823         case 2:
1824                 data->bsize = 0;
1825         case 3:
1826                 if (data->flags & NFS_MOUNT_VER3)
1827                         goto out_no_v3;
1828                 data->root.size = NFS2_FHSIZE;
1829                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1830         case 4:
1831                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1832                         goto out_no_sec;
1833         case 5:
1834                 memset(data->context, 0, sizeof(data->context));
1835         case 6:
1836                 if (data->flags & NFS_MOUNT_VER3) {
1837                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1838                                 goto out_invalid_fh;
1839                         mntfh->size = data->root.size;
1840                         args->version = 3;
1841                 } else {
1842                         mntfh->size = NFS2_FHSIZE;
1843                         args->version = 2;
1844                 }
1845
1846
1847                 memcpy(mntfh->data, data->root.data, mntfh->size);
1848                 if (mntfh->size < sizeof(mntfh->data))
1849                         memset(mntfh->data + mntfh->size, 0,
1850                                sizeof(mntfh->data) - mntfh->size);
1851
1852                 /*
1853                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1854                  * can deal with.
1855                  */
1856                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1857                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1858                 args->rsize             = data->rsize;
1859                 args->wsize             = data->wsize;
1860                 args->timeo             = data->timeo;
1861                 args->retrans           = data->retrans;
1862                 args->acregmin          = data->acregmin;
1863                 args->acregmax          = data->acregmax;
1864                 args->acdirmin          = data->acdirmin;
1865                 args->acdirmax          = data->acdirmax;
1866                 args->need_mount        = false;
1867
1868                 memcpy(sap, &data->addr, sizeof(data->addr));
1869                 args->nfs_server.addrlen = sizeof(data->addr);
1870                 args->nfs_server.port = ntohs(data->addr.sin_port);
1871                 if (!nfs_verify_server_address(sap))
1872                         goto out_no_address;
1873
1874                 if (!(data->flags & NFS_MOUNT_TCP))
1875                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1876                 /* N.B. caller will free nfs_server.hostname in all cases */
1877                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1878                 args->namlen            = data->namlen;
1879                 args->bsize             = data->bsize;
1880
1881                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1882                         args->auth_flavors[0] = data->pseudoflavor;
1883                 if (!args->nfs_server.hostname)
1884                         goto out_nomem;
1885
1886                 if (!(data->flags & NFS_MOUNT_NONLM))
1887                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1888                                          NFS_MOUNT_LOCAL_FCNTL);
1889                 else
1890                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1891                                         NFS_MOUNT_LOCAL_FCNTL);
1892                 /*
1893                  * The legacy version 6 binary mount data from userspace has a
1894                  * field used only to transport selinux information into the
1895                  * the kernel.  To continue to support that functionality we
1896                  * have a touch of selinux knowledge here in the NFS code. The
1897                  * userspace code converted context=blah to just blah so we are
1898                  * converting back to the full string selinux understands.
1899                  */
1900                 if (data->context[0]){
1901 #ifdef CONFIG_SECURITY_SELINUX
1902                         int rc;
1903                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1904                         if (!opts_str)
1905                                 return -ENOMEM;
1906                         strcpy(opts_str, "context=");
1907                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1908                         strcat(opts_str, &data->context[0]);
1909                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1910                         kfree(opts_str);
1911                         if (rc)
1912                                 return rc;
1913 #else
1914                         return -EINVAL;
1915 #endif
1916                 }
1917
1918                 break;
1919         default:
1920                 return NFS_TEXT_DATA;
1921         }
1922
1923 #if !IS_ENABLED(CONFIG_NFS_V3)
1924         if (args->version == 3)
1925                 goto out_v3_not_compiled;
1926 #endif /* !CONFIG_NFS_V3 */
1927
1928         return 0;
1929
1930 out_no_data:
1931         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1932         return -EINVAL;
1933
1934 out_no_v3:
1935         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1936                  data->version);
1937         return -EINVAL;
1938
1939 out_no_sec:
1940         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1941         return -EINVAL;
1942
1943 #if !IS_ENABLED(CONFIG_NFS_V3)
1944 out_v3_not_compiled:
1945         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1946         return -EPROTONOSUPPORT;
1947 #endif /* !CONFIG_NFS_V3 */
1948
1949 out_nomem:
1950         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1951         return -ENOMEM;
1952
1953 out_no_address:
1954         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1955         return -EINVAL;
1956
1957 out_invalid_fh:
1958         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1959         return -EINVAL;
1960 }
1961
1962 #if IS_ENABLED(CONFIG_NFS_V4)
1963 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1964                                    void *options,
1965                                    struct nfs_parsed_mount_data *args,
1966                                    struct nfs_fh *mntfh,
1967                                    const char *dev_name)
1968 {
1969         if (fs_type == &nfs_fs_type)
1970                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1971         return nfs4_validate_mount_data(options, args, dev_name);
1972 }
1973 #else
1974 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1975                                    void *options,
1976                                    struct nfs_parsed_mount_data *args,
1977                                    struct nfs_fh *mntfh,
1978                                    const char *dev_name)
1979 {
1980         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1981 }
1982 #endif
1983
1984 static int nfs_validate_text_mount_data(void *options,
1985                                         struct nfs_parsed_mount_data *args,
1986                                         const char *dev_name)
1987 {
1988         int port = 0;
1989         int max_namelen = PAGE_SIZE;
1990         int max_pathlen = NFS_MAXPATHLEN;
1991         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1992
1993         if (nfs_parse_mount_options((char *)options, args) == 0)
1994                 return -EINVAL;
1995
1996         if (!nfs_verify_server_address(sap))
1997                 goto out_no_address;
1998
1999         if (args->version == 4) {
2000 #if IS_ENABLED(CONFIG_NFS_V4)
2001                 port = NFS_PORT;
2002                 max_namelen = NFS4_MAXNAMLEN;
2003                 max_pathlen = NFS4_MAXPATHLEN;
2004                 nfs_validate_transport_protocol(args);
2005                 nfs4_validate_mount_flags(args);
2006 #else
2007                 goto out_v4_not_compiled;
2008 #endif /* CONFIG_NFS_V4 */
2009         } else
2010                 nfs_set_mount_transport_protocol(args);
2011
2012         nfs_set_port(sap, &args->nfs_server.port, port);
2013
2014         if (args->auth_flavor_len > 1)
2015                 goto out_bad_auth;
2016
2017         return nfs_parse_devname(dev_name,
2018                                    &args->nfs_server.hostname,
2019                                    max_namelen,
2020                                    &args->nfs_server.export_path,
2021                                    max_pathlen);
2022
2023 #if !IS_ENABLED(CONFIG_NFS_V4)
2024 out_v4_not_compiled:
2025         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2026         return -EPROTONOSUPPORT;
2027 #endif /* !CONFIG_NFS_V4 */
2028
2029 out_no_address:
2030         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2031         return -EINVAL;
2032
2033 out_bad_auth:
2034         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2035         return -EINVAL;
2036 }
2037
2038 static int
2039 nfs_compare_remount_data(struct nfs_server *nfss,
2040                          struct nfs_parsed_mount_data *data)
2041 {
2042         if (data->flags != nfss->flags ||
2043             data->rsize != nfss->rsize ||
2044             data->wsize != nfss->wsize ||
2045             data->retrans != nfss->client->cl_timeout->to_retries ||
2046             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2047             data->acregmin != nfss->acregmin / HZ ||
2048             data->acregmax != nfss->acregmax / HZ ||
2049             data->acdirmin != nfss->acdirmin / HZ ||
2050             data->acdirmax != nfss->acdirmax / HZ ||
2051             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2052             data->nfs_server.port != nfss->port ||
2053             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2054             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2055                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2056                 return -EINVAL;
2057
2058         return 0;
2059 }
2060
2061 int
2062 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2063 {
2064         int error;
2065         struct nfs_server *nfss = sb->s_fs_info;
2066         struct nfs_parsed_mount_data *data;
2067         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2068         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2069         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2070
2071         /*
2072          * Userspace mount programs that send binary options generally send
2073          * them populated with default values. We have no way to know which
2074          * ones were explicitly specified. Fall back to legacy behavior and
2075          * just return success.
2076          */
2077         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2078             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2079                                            options->version <= 6))))
2080                 return 0;
2081
2082         data = kzalloc(sizeof(*data), GFP_KERNEL);
2083         if (data == NULL)
2084                 return -ENOMEM;
2085
2086         /* fill out struct with values from existing mount */
2087         data->flags = nfss->flags;
2088         data->rsize = nfss->rsize;
2089         data->wsize = nfss->wsize;
2090         data->retrans = nfss->client->cl_timeout->to_retries;
2091         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2092         data->acregmin = nfss->acregmin / HZ;
2093         data->acregmax = nfss->acregmax / HZ;
2094         data->acdirmin = nfss->acdirmin / HZ;
2095         data->acdirmax = nfss->acdirmax / HZ;
2096         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2097         data->nfs_server.port = nfss->port;
2098         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2099         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2100                 data->nfs_server.addrlen);
2101
2102         /* overwrite those values with any that were specified */
2103         error = nfs_parse_mount_options((char *)options, data);
2104         if (error < 0)
2105                 goto out;
2106
2107         /*
2108          * noac is a special case. It implies -o sync, but that's not
2109          * necessarily reflected in the mtab options. do_remount_sb
2110          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2111          * remount options, so we have to explicitly reset it.
2112          */
2113         if (data->flags & NFS_MOUNT_NOAC)
2114                 *flags |= MS_SYNCHRONOUS;
2115
2116         /* compare new mount options with old ones */
2117         error = nfs_compare_remount_data(nfss, data);
2118 out:
2119         kfree(data);
2120         return error;
2121 }
2122 EXPORT_SYMBOL_GPL(nfs_remount);
2123
2124 /*
2125  * Initialise the common bits of the superblock
2126  */
2127 inline void nfs_initialise_sb(struct super_block *sb)
2128 {
2129         struct nfs_server *server = NFS_SB(sb);
2130
2131         sb->s_magic = NFS_SUPER_MAGIC;
2132
2133         /* We probably want something more informative here */
2134         snprintf(sb->s_id, sizeof(sb->s_id),
2135                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2136
2137         if (sb->s_blocksize == 0)
2138                 sb->s_blocksize = nfs_block_bits(server->wsize,
2139                                                  &sb->s_blocksize_bits);
2140
2141         sb->s_bdi = &server->backing_dev_info;
2142
2143         nfs_super_set_maxbytes(sb, server->maxfilesize);
2144 }
2145
2146 /*
2147  * Finish setting up an NFS2/3 superblock
2148  */
2149 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2150 {
2151         struct nfs_parsed_mount_data *data = mount_info->parsed;
2152         struct nfs_server *server = NFS_SB(sb);
2153
2154         sb->s_blocksize_bits = 0;
2155         sb->s_blocksize = 0;
2156         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2157         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2158         if (data && data->bsize)
2159                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2160
2161         if (server->nfs_client->rpc_ops->version != 2) {
2162                 /* The VFS shouldn't apply the umask to mode bits. We will do
2163                  * so ourselves when necessary.
2164                  */
2165                 sb->s_flags |= MS_POSIXACL;
2166                 sb->s_time_gran = 1;
2167         }
2168
2169         nfs_initialise_sb(sb);
2170 }
2171 EXPORT_SYMBOL_GPL(nfs_fill_super);
2172
2173 /*
2174  * Finish setting up a cloned NFS2/3/4 superblock
2175  */
2176 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2177 {
2178         const struct super_block *old_sb = mount_info->cloned->sb;
2179         struct nfs_server *server = NFS_SB(sb);
2180
2181         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2182         sb->s_blocksize = old_sb->s_blocksize;
2183         sb->s_maxbytes = old_sb->s_maxbytes;
2184         sb->s_xattr = old_sb->s_xattr;
2185         sb->s_op = old_sb->s_op;
2186         sb->s_time_gran = 1;
2187
2188         if (server->nfs_client->rpc_ops->version != 2) {
2189                 /* The VFS shouldn't apply the umask to mode bits. We will do
2190                  * so ourselves when necessary.
2191                  */
2192                 sb->s_flags |= MS_POSIXACL;
2193         }
2194
2195         nfs_initialise_sb(sb);
2196 }
2197
2198 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2199 {
2200         const struct nfs_server *a = s->s_fs_info;
2201         const struct rpc_clnt *clnt_a = a->client;
2202         const struct rpc_clnt *clnt_b = b->client;
2203
2204         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2205                 goto Ebusy;
2206         if (a->nfs_client != b->nfs_client)
2207                 goto Ebusy;
2208         if (a->flags != b->flags)
2209                 goto Ebusy;
2210         if (a->wsize != b->wsize)
2211                 goto Ebusy;
2212         if (a->rsize != b->rsize)
2213                 goto Ebusy;
2214         if (a->acregmin != b->acregmin)
2215                 goto Ebusy;
2216         if (a->acregmax != b->acregmax)
2217                 goto Ebusy;
2218         if (a->acdirmin != b->acdirmin)
2219                 goto Ebusy;
2220         if (a->acdirmax != b->acdirmax)
2221                 goto Ebusy;
2222         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2223                 goto Ebusy;
2224         return 1;
2225 Ebusy:
2226         return 0;
2227 }
2228
2229 struct nfs_sb_mountdata {
2230         struct nfs_server *server;
2231         int mntflags;
2232 };
2233
2234 static int nfs_set_super(struct super_block *s, void *data)
2235 {
2236         struct nfs_sb_mountdata *sb_mntdata = data;
2237         struct nfs_server *server = sb_mntdata->server;
2238         int ret;
2239
2240         s->s_flags = sb_mntdata->mntflags;
2241         s->s_fs_info = server;
2242         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2243         ret = set_anon_super(s, server);
2244         if (ret == 0)
2245                 server->s_dev = s->s_dev;
2246         return ret;
2247 }
2248
2249 static int nfs_compare_super_address(struct nfs_server *server1,
2250                                      struct nfs_server *server2)
2251 {
2252         struct sockaddr *sap1, *sap2;
2253
2254         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2255         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2256
2257         if (sap1->sa_family != sap2->sa_family)
2258                 return 0;
2259
2260         switch (sap1->sa_family) {
2261         case AF_INET: {
2262                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2263                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2264                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2265                         return 0;
2266                 if (sin1->sin_port != sin2->sin_port)
2267                         return 0;
2268                 break;
2269         }
2270         case AF_INET6: {
2271                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2272                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2273                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2274                         return 0;
2275                 if (sin1->sin6_port != sin2->sin6_port)
2276                         return 0;
2277                 break;
2278         }
2279         default:
2280                 return 0;
2281         }
2282
2283         return 1;
2284 }
2285
2286 static int nfs_compare_super(struct super_block *sb, void *data)
2287 {
2288         struct nfs_sb_mountdata *sb_mntdata = data;
2289         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2290         int mntflags = sb_mntdata->mntflags;
2291
2292         if (!nfs_compare_super_address(old, server))
2293                 return 0;
2294         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2295         if (old->flags & NFS_MOUNT_UNSHARED)
2296                 return 0;
2297         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2298                 return 0;
2299         return nfs_compare_mount_options(sb, server, mntflags);
2300 }
2301
2302 #ifdef CONFIG_NFS_FSCACHE
2303 static void nfs_get_cache_cookie(struct super_block *sb,
2304                                  struct nfs_parsed_mount_data *parsed,
2305                                  struct nfs_clone_mount *cloned)
2306 {
2307         char *uniq = NULL;
2308         int ulen = 0;
2309
2310         if (parsed && parsed->fscache_uniq) {
2311                 uniq = parsed->fscache_uniq;
2312                 ulen = strlen(parsed->fscache_uniq);
2313         } else if (cloned) {
2314                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2315                 if (mnt_s->fscache_key) {
2316                         uniq = mnt_s->fscache_key->key.uniquifier;
2317                         ulen = mnt_s->fscache_key->key.uniq_len;
2318                 };
2319         }
2320
2321         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2322 }
2323 #else
2324 static void nfs_get_cache_cookie(struct super_block *sb,
2325                                  struct nfs_parsed_mount_data *parsed,
2326                                  struct nfs_clone_mount *cloned)
2327 {
2328 }
2329 #endif
2330
2331 static int nfs_bdi_register(struct nfs_server *server)
2332 {
2333         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2334 }
2335
2336 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2337                         struct nfs_mount_info *mount_info)
2338 {
2339         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2340 }
2341 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2342
2343 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2344                           struct nfs_mount_info *mount_info)
2345 {
2346         /* clone any lsm security options from the parent to the new sb */
2347         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2348         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2349                 return -ESTALE;
2350         return 0;
2351 }
2352 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2353
2354 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2355                                    int flags, const char *dev_name,
2356                                    struct nfs_mount_info *mount_info,
2357                                    struct nfs_subversion *nfs_mod)
2358 {
2359         struct super_block *s;
2360         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2361         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2362         struct nfs_sb_mountdata sb_mntdata = {
2363                 .mntflags = flags,
2364                 .server = server,
2365         };
2366         int error;
2367
2368         if (server->flags & NFS_MOUNT_UNSHARED)
2369                 compare_super = NULL;
2370
2371         /* -o noac implies -o sync */
2372         if (server->flags & NFS_MOUNT_NOAC)
2373                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2374
2375         /* Get a superblock - note that we may end up sharing one that already exists */
2376         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2377         if (IS_ERR(s)) {
2378                 mntroot = ERR_CAST(s);
2379                 goto out_err_nosb;
2380         }
2381
2382         if (s->s_fs_info != server) {
2383                 nfs_free_server(server);
2384                 server = NULL;
2385         } else {
2386                 error = nfs_bdi_register(server);
2387                 if (error) {
2388                         mntroot = ERR_PTR(error);
2389                         goto error_splat_bdi;
2390                 }
2391         }
2392
2393         if (!s->s_root) {
2394                 /* initial superblock/root creation */
2395                 mount_info->fill_super(s, mount_info);
2396                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2397         }
2398
2399         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2400         if (IS_ERR(mntroot))
2401                 goto error_splat_super;
2402
2403         error = mount_info->set_security(s, mntroot, mount_info);
2404         if (error)
2405                 goto error_splat_root;
2406
2407         s->s_flags |= MS_ACTIVE;
2408
2409 out:
2410         return mntroot;
2411
2412 out_err_nosb:
2413         nfs_free_server(server);
2414         goto out;
2415
2416 error_splat_root:
2417         dput(mntroot);
2418         mntroot = ERR_PTR(error);
2419 error_splat_super:
2420         if (server && !s->s_root)
2421                 bdi_unregister(&server->backing_dev_info);
2422 error_splat_bdi:
2423         deactivate_locked_super(s);
2424         goto out;
2425 }
2426 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2427
2428 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2429         int flags, const char *dev_name, void *raw_data)
2430 {
2431         struct nfs_mount_info mount_info = {
2432                 .fill_super = nfs_fill_super,
2433                 .set_security = nfs_set_sb_security,
2434         };
2435         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2436         struct nfs_subversion *nfs_mod;
2437         int error;
2438
2439         mount_info.parsed = nfs_alloc_parsed_mount_data();
2440         mount_info.mntfh = nfs_alloc_fhandle();
2441         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2442                 goto out;
2443
2444         /* Validate the mount data */
2445         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2446         if (error == NFS_TEXT_DATA)
2447                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2448         if (error < 0) {
2449                 mntroot = ERR_PTR(error);
2450                 goto out;
2451         }
2452
2453         nfs_mod = get_nfs_version(mount_info.parsed->version);
2454         if (IS_ERR(nfs_mod)) {
2455                 mntroot = ERR_CAST(nfs_mod);
2456                 goto out;
2457         }
2458
2459         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2460
2461         put_nfs_version(nfs_mod);
2462 out:
2463         nfs_free_parsed_mount_data(mount_info.parsed);
2464         nfs_free_fhandle(mount_info.mntfh);
2465         return mntroot;
2466 }
2467 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2468
2469 /*
2470  * Ensure that we unregister the bdi before kill_anon_super
2471  * releases the device name
2472  */
2473 void nfs_put_super(struct super_block *s)
2474 {
2475         struct nfs_server *server = NFS_SB(s);
2476
2477         bdi_unregister(&server->backing_dev_info);
2478 }
2479 EXPORT_SYMBOL_GPL(nfs_put_super);
2480
2481 /*
2482  * Destroy an NFS2/3 superblock
2483  */
2484 void nfs_kill_super(struct super_block *s)
2485 {
2486         struct nfs_server *server = NFS_SB(s);
2487
2488         kill_anon_super(s);
2489         nfs_fscache_release_super_cookie(s);
2490         nfs_free_server(server);
2491 }
2492 EXPORT_SYMBOL_GPL(nfs_kill_super);
2493
2494 /*
2495  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2496  */
2497 struct dentry *
2498 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2499                 const char *dev_name, void *raw_data)
2500 {
2501         struct nfs_clone_mount *data = raw_data;
2502         struct nfs_mount_info mount_info = {
2503                 .fill_super = nfs_clone_super,
2504                 .set_security = nfs_clone_sb_security,
2505                 .cloned = data,
2506         };
2507         struct nfs_server *server;
2508         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2509         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2510         int error;
2511
2512         dprintk("--> nfs_xdev_mount_common()\n");
2513
2514         mount_info.mntfh = mount_info.cloned->fh;
2515
2516         /* create a new volume representation */
2517         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2518         if (IS_ERR(server)) {
2519                 error = PTR_ERR(server);
2520                 goto out_err;
2521         }
2522
2523         mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, nfs_mod);
2524         dprintk("<-- nfs_xdev_mount_common() = 0\n");
2525 out:
2526         return mntroot;
2527
2528 out_err:
2529         dprintk("<-- nfs_xdev_mount_common() = %d [error]\n", error);
2530         goto out;
2531 }
2532
2533 #if IS_ENABLED(CONFIG_NFS_V4)
2534
2535 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2536 {
2537         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2538                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2539 }
2540
2541 /*
2542  * Validate NFSv4 mount options
2543  */
2544 static int nfs4_validate_mount_data(void *options,
2545                                     struct nfs_parsed_mount_data *args,
2546                                     const char *dev_name)
2547 {
2548         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2549         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2550         char *c;
2551
2552         if (data == NULL)
2553                 goto out_no_data;
2554
2555         args->version = 4;
2556
2557         switch (data->version) {
2558         case 1:
2559                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2560                         goto out_no_address;
2561                 if (data->host_addrlen == 0)
2562                         goto out_no_address;
2563                 args->nfs_server.addrlen = data->host_addrlen;
2564                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2565                         return -EFAULT;
2566                 if (!nfs_verify_server_address(sap))
2567                         goto out_no_address;
2568                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2569
2570                 if (data->auth_flavourlen) {
2571                         if (data->auth_flavourlen > 1)
2572                                 goto out_inval_auth;
2573                         if (copy_from_user(&args->auth_flavors[0],
2574                                            data->auth_flavours,
2575                                            sizeof(args->auth_flavors[0])))
2576                                 return -EFAULT;
2577                 }
2578
2579                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2580                 if (IS_ERR(c))
2581                         return PTR_ERR(c);
2582                 args->nfs_server.hostname = c;
2583
2584                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2585                 if (IS_ERR(c))
2586                         return PTR_ERR(c);
2587                 args->nfs_server.export_path = c;
2588                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2589
2590                 c = strndup_user(data->client_addr.data, 16);
2591                 if (IS_ERR(c))
2592                         return PTR_ERR(c);
2593                 args->client_address = c;
2594
2595                 /*
2596                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2597                  * can deal with.
2598                  */
2599
2600                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2601                 args->rsize     = data->rsize;
2602                 args->wsize     = data->wsize;
2603                 args->timeo     = data->timeo;
2604                 args->retrans   = data->retrans;
2605                 args->acregmin  = data->acregmin;
2606                 args->acregmax  = data->acregmax;
2607                 args->acdirmin  = data->acdirmin;
2608                 args->acdirmax  = data->acdirmax;
2609                 args->nfs_server.protocol = data->proto;
2610                 nfs_validate_transport_protocol(args);
2611
2612                 break;
2613         default:
2614                 return NFS_TEXT_DATA;
2615         }
2616
2617         return 0;
2618
2619 out_no_data:
2620         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2621         return -EINVAL;
2622
2623 out_inval_auth:
2624         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2625                  data->auth_flavourlen);
2626         return -EINVAL;
2627
2628 out_no_address:
2629         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2630         return -EINVAL;
2631 }
2632
2633 /*
2634  * NFS v4 module parameters need to stay in the
2635  * NFS client for backwards compatibility
2636  */
2637 unsigned int nfs_callback_set_tcpport;
2638 unsigned short nfs_callback_tcpport;
2639 /* Default cache timeout is 10 minutes */
2640 unsigned int nfs_idmap_cache_timeout = 600;
2641 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2642 bool nfs4_disable_idmapping = true;
2643 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2644 unsigned short send_implementation_id = 1;
2645
2646 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2647 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2648 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2649 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2650 EXPORT_SYMBOL_GPL(max_session_slots);
2651 EXPORT_SYMBOL_GPL(send_implementation_id);
2652
2653 #define NFS_CALLBACK_MAXPORTNR (65535U)
2654
2655 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2656 {
2657         unsigned long num;
2658         int ret;
2659
2660         if (!val)
2661                 return -EINVAL;
2662         ret = strict_strtoul(val, 0, &num);
2663         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2664                 return -EINVAL;
2665         *((unsigned int *)kp->arg) = num;
2666         return 0;
2667 }
2668 static struct kernel_param_ops param_ops_portnr = {
2669         .set = param_set_portnr,
2670         .get = param_get_uint,
2671 };
2672 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2673
2674 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2675 module_param(nfs_idmap_cache_timeout, int, 0644);
2676 module_param(nfs4_disable_idmapping, bool, 0644);
2677 MODULE_PARM_DESC(nfs4_disable_idmapping,
2678                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2679 module_param(max_session_slots, ushort, 0644);
2680 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2681                 "requests the client will negotiate");
2682 module_param(send_implementation_id, ushort, 0644);
2683 MODULE_PARM_DESC(send_implementation_id,
2684                 "Send implementation ID with NFSv4.1 exchange_id");
2685 MODULE_ALIAS("nfs4");
2686
2687 #endif /* CONFIG_NFS_V4 */