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 #include <linux/kthread.h>
  58
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67 #include "nfs4session.h"
  68 #include "pnfs.h"
  69 #include "nfs.h"
  70
  71 #define NFSDBG_FACILITY         NFSDBG_VFS
  72 #define NFS_TEXT_DATA           1
  73
  74 #if IS_ENABLED(CONFIG_NFS_V3)
  75 #define NFS_DEFAULT_VERSION 3
  76 #else
  77 #define NFS_DEFAULT_VERSION 2
  78 #endif
  79
  80 enum {
  81         /* Mount options that take no arguments */
  82         Opt_soft, Opt_hard,
  83         Opt_posix, Opt_noposix,
  84         Opt_cto, Opt_nocto,
  85         Opt_ac, Opt_noac,
  86         Opt_lock, Opt_nolock,
  87         Opt_udp, Opt_tcp, Opt_rdma,
  88         Opt_acl, Opt_noacl,
  89         Opt_rdirplus, Opt_nordirplus,
  90         Opt_sharecache, Opt_nosharecache,
  91         Opt_resvport, Opt_noresvport,
  92         Opt_fscache, Opt_nofscache,
  93         Opt_migration, Opt_nomigration,
  94
  95         /* Mount options that take integer arguments */
  96         Opt_port,
  97         Opt_rsize, Opt_wsize, Opt_bsize,
  98         Opt_timeo, Opt_retrans,
  99         Opt_acregmin, Opt_acregmax,
 100         Opt_acdirmin, Opt_acdirmax,
 101         Opt_actimeo,
 102         Opt_namelen,
 103         Opt_mountport,
 104         Opt_mountvers,
 105         Opt_minorversion,
 106
 107         /* Mount options that take string arguments */
 108         Opt_nfsvers,
 109         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 110         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 111         Opt_lookupcache,
 112         Opt_fscache_uniq,
 113         Opt_local_lock,
 114
 115         /* Special mount options */
 116         Opt_userspace, Opt_deprecated, Opt_sloppy,
 117
 118         Opt_err
 119 };
 120
 121 static const match_table_t nfs_mount_option_tokens = {
 122         { Opt_userspace, "bg" },
 123         { Opt_userspace, "fg" },
 124         { Opt_userspace, "retry=%s" },
 125
 126         { Opt_sloppy, "sloppy" },
 127
 128         { Opt_soft, "soft" },
 129         { Opt_hard, "hard" },
 130         { Opt_deprecated, "intr" },
 131         { Opt_deprecated, "nointr" },
 132         { Opt_posix, "posix" },
 133         { Opt_noposix, "noposix" },
 134         { Opt_cto, "cto" },
 135         { Opt_nocto, "nocto" },
 136         { Opt_ac, "ac" },
 137         { Opt_noac, "noac" },
 138         { Opt_lock, "lock" },
 139         { Opt_nolock, "nolock" },
 140         { Opt_udp, "udp" },
 141         { Opt_tcp, "tcp" },
 142         { Opt_rdma, "rdma" },
 143         { Opt_acl, "acl" },
 144         { Opt_noacl, "noacl" },
 145         { Opt_rdirplus, "rdirplus" },
 146         { Opt_nordirplus, "nordirplus" },
 147         { Opt_sharecache, "sharecache" },
 148         { Opt_nosharecache, "nosharecache" },
 149         { Opt_resvport, "resvport" },
 150         { Opt_noresvport, "noresvport" },
 151         { Opt_fscache, "fsc" },
 152         { Opt_nofscache, "nofsc" },
 153         { Opt_migration, "migration" },
 154         { Opt_nomigration, "nomigration" },
 155
 156         { Opt_port, "port=%s" },
 157         { Opt_rsize, "rsize=%s" },
 158         { Opt_wsize, "wsize=%s" },
 159         { Opt_bsize, "bsize=%s" },
 160         { Opt_timeo, "timeo=%s" },
 161         { Opt_retrans, "retrans=%s" },
 162         { Opt_acregmin, "acregmin=%s" },
 163         { Opt_acregmax, "acregmax=%s" },
 164         { Opt_acdirmin, "acdirmin=%s" },
 165         { Opt_acdirmax, "acdirmax=%s" },
 166         { Opt_actimeo, "actimeo=%s" },
 167         { Opt_namelen, "namlen=%s" },
 168         { Opt_mountport, "mountport=%s" },
 169         { Opt_mountvers, "mountvers=%s" },
 170         { Opt_minorversion, "minorversion=%s" },
 171
 172         { Opt_nfsvers, "nfsvers=%s" },
 173         { Opt_nfsvers, "vers=%s" },
 174
 175         { Opt_sec, "sec=%s" },
 176         { Opt_proto, "proto=%s" },
 177         { Opt_mountproto, "mountproto=%s" },
 178         { Opt_addr, "addr=%s" },
 179         { Opt_clientaddr, "clientaddr=%s" },
 180         { Opt_mounthost, "mounthost=%s" },
 181         { Opt_mountaddr, "mountaddr=%s" },
 182
 183         { Opt_lookupcache, "lookupcache=%s" },
 184         { Opt_fscache_uniq, "fsc=%s" },
 185         { Opt_local_lock, "local_lock=%s" },
 186
 187         /* The following needs to be listed after all other options */
 188         { Opt_nfsvers, "v%s" },
 189
 190         { Opt_err, NULL }
 191 };
 192
 193 enum {
 194         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 195
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205
 206         { Opt_xprt_err, NULL }
 207 };
 208
 209 enum {
 210         Opt_sec_none, Opt_sec_sys,
 211         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 212         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 213         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 214
 215         Opt_sec_err
 216 };
 217
 218 static const match_table_t nfs_secflavor_tokens = {
 219         { Opt_sec_none, "none" },
 220         { Opt_sec_none, "null" },
 221         { Opt_sec_sys, "sys" },
 222
 223         { Opt_sec_krb5, "krb5" },
 224         { Opt_sec_krb5i, "krb5i" },
 225         { Opt_sec_krb5p, "krb5p" },
 226
 227         { Opt_sec_lkey, "lkey" },
 228         { Opt_sec_lkeyi, "lkeyi" },
 229         { Opt_sec_lkeyp, "lkeyp" },
 230
 231         { Opt_sec_spkm, "spkm3" },
 232         { Opt_sec_spkmi, "spkm3i" },
 233         { Opt_sec_spkmp, "spkm3p" },
 234
 235         { Opt_sec_err, NULL }
 236 };
 237
 238 enum {
 239         Opt_lookupcache_all, Opt_lookupcache_positive,
 240         Opt_lookupcache_none,
 241
 242         Opt_lookupcache_err
 243 };
 244
 245 static match_table_t nfs_lookupcache_tokens = {
 246         { Opt_lookupcache_all, "all" },
 247         { Opt_lookupcache_positive, "pos" },
 248         { Opt_lookupcache_positive, "positive" },
 249         { Opt_lookupcache_none, "none" },
 250
 251         { Opt_lookupcache_err, NULL }
 252 };
 253
 254 enum {
 255         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 256         Opt_local_lock_none,
 257
 258         Opt_local_lock_err
 259 };
 260
 261 static match_table_t nfs_local_lock_tokens = {
 262         { Opt_local_lock_all, "all" },
 263         { Opt_local_lock_flock, "flock" },
 264         { Opt_local_lock_posix, "posix" },
 265         { Opt_local_lock_none, "none" },
 266
 267         { Opt_local_lock_err, NULL }
 268 };
 269
 270 enum {
 271         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 272         Opt_vers_4_1,
 273
 274         Opt_vers_err
 275 };
 276
 277 static match_table_t nfs_vers_tokens = {
 278         { Opt_vers_2, "2" },
 279         { Opt_vers_3, "3" },
 280         { Opt_vers_4, "4" },
 281         { Opt_vers_4_0, "4.0" },
 282         { Opt_vers_4_1, "4.1" },
 283
 284         { Opt_vers_err, NULL }
 285 };
 286
 287 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 288                 int flags, const char *dev_name, void *raw_data);
 289
 290 struct file_system_type nfs_fs_type = {
 291         .owner          = THIS_MODULE,
 292         .name           = "nfs",
 293         .mount          = nfs_fs_mount,
 294         .kill_sb        = nfs_kill_super,
 295         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 296 };
 297 EXPORT_SYMBOL_GPL(nfs_fs_type);
 298
 299 struct file_system_type nfs_xdev_fs_type = {
 300         .owner          = THIS_MODULE,
 301         .name           = "nfs",
 302         .mount          = nfs_xdev_mount,
 303         .kill_sb        = nfs_kill_super,
 304         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 305 };
 306
 307 const struct super_operations nfs_sops = {
 308         .alloc_inode    = nfs_alloc_inode,
 309         .destroy_inode  = nfs_destroy_inode,
 310         .write_inode    = nfs_write_inode,
 311         .drop_inode     = nfs_drop_inode,
 312         .put_super      = nfs_put_super,
 313         .statfs         = nfs_statfs,
 314         .evict_inode    = nfs_evict_inode,
 315         .umount_begin   = nfs_umount_begin,
 316         .show_options   = nfs_show_options,
 317         .show_devname   = nfs_show_devname,
 318         .show_path      = nfs_show_path,
 319         .show_stats     = nfs_show_stats,
 320         .remount_fs     = nfs_remount,
 321 };
 322 EXPORT_SYMBOL_GPL(nfs_sops);
 323
 324 #if IS_ENABLED(CONFIG_NFS_V4)
 325 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 326 static int nfs4_validate_mount_data(void *options,
 327         struct nfs_parsed_mount_data *args, const char *dev_name);
 328
 329 struct file_system_type nfs4_fs_type = {
 330         .owner          = THIS_MODULE,
 331         .name           = "nfs4",
 332         .mount          = nfs_fs_mount,
 333         .kill_sb        = nfs_kill_super,
 334         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 335 };
 336 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 337
 338 static int __init register_nfs4_fs(void)
 339 {
 340         return register_filesystem(&nfs4_fs_type);
 341 }
 342
 343 static void unregister_nfs4_fs(void)
 344 {
 345         unregister_filesystem(&nfs4_fs_type);
 346 }
 347 #else
 348 static int __init register_nfs4_fs(void)
 349 {
 350         return 0;
 351 }
 352
 353 static void unregister_nfs4_fs(void)
 354 {
 355 }
 356 #endif
 357
 358 static struct shrinker acl_shrinker = {
 359         .shrink         = nfs_access_cache_shrinker,
 360         .seeks          = DEFAULT_SEEKS,
 361 };
 362
 363 /*
 364  * Register the NFS filesystems
 365  */
 366 int __init register_nfs_fs(void)
 367 {
 368         int ret;
 369
 370         ret = register_filesystem(&nfs_fs_type);
 371         if (ret < 0)
 372                 goto error_0;
 373
 374         ret = register_nfs4_fs();
 375         if (ret < 0)
 376                 goto error_1;
 377
 378         ret = nfs_register_sysctl();
 379         if (ret < 0)
 380                 goto error_2;
 381         register_shrinker(&acl_shrinker);
 382         return 0;
 383
 384 error_2:
 385         unregister_nfs4_fs();
 386 error_1:
 387         unregister_filesystem(&nfs_fs_type);
 388 error_0:
 389         return ret;
 390 }
 391
 392 /*
 393  * Unregister the NFS filesystems
 394  */
 395 void __exit unregister_nfs_fs(void)
 396 {
 397         unregister_shrinker(&acl_shrinker);
 398         nfs_unregister_sysctl();
 399         unregister_nfs4_fs();
 400         unregister_filesystem(&nfs_fs_type);
 401 }
 402
 403 void nfs_sb_active(struct super_block *sb)
 404 {
 405         struct nfs_server *server = NFS_SB(sb);
 406
 407         if (atomic_inc_return(&server->active) == 1)
 408                 atomic_inc(&sb->s_active);
 409 }
 410 EXPORT_SYMBOL_GPL(nfs_sb_active);
 411
 412 void nfs_sb_deactive(struct super_block *sb)
 413 {
 414         struct nfs_server *server = NFS_SB(sb);
 415
 416         if (atomic_dec_and_test(&server->active))
 417                 deactivate_super(sb);
 418 }
 419 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 420
 421 static int nfs_deactivate_super_async_work(void *ptr)
 422 {
 423         struct super_block *sb = ptr;
 424
 425         deactivate_super(sb);
 426         module_put_and_exit(0);
 427         return 0;
 428 }
 429
 430 /*
 431  * same effect as deactivate_super, but will do final unmount in kthread
 432  * context
 433  */
 434 static void nfs_deactivate_super_async(struct super_block *sb)
 435 {
 436         struct task_struct *task;
 437         char buf[INET6_ADDRSTRLEN + 1];
 438         struct nfs_server *server = NFS_SB(sb);
 439         struct nfs_client *clp = server->nfs_client;
 440
 441         if (!atomic_add_unless(&sb->s_active, -1, 1)) {
 442                 rcu_read_lock();
 443                 snprintf(buf, sizeof(buf),
 444                         rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 445                 rcu_read_unlock();
 446
 447                 __module_get(THIS_MODULE);
 448                 task = kthread_run(nfs_deactivate_super_async_work, sb,
 449                                 "%s-deactivate-super", buf);
 450                 if (IS_ERR(task)) {
 451                         pr_err("%s: kthread_run: %ld\n",
 452                                 __func__, PTR_ERR(task));
 453                         /* make synchronous call and hope for the best */
 454                         deactivate_super(sb);
 455                         module_put(THIS_MODULE);
 456                 }
 457         }
 458 }
 459
 460 void nfs_sb_deactive_async(struct super_block *sb)
 461 {
 462         struct nfs_server *server = NFS_SB(sb);
 463
 464         if (atomic_dec_and_test(&server->active))
 465                 nfs_deactivate_super_async(sb);
 466 }
 467 EXPORT_SYMBOL_GPL(nfs_sb_deactive_async);
 468
 469 /*
 470  * Deliver file system statistics to userspace
 471  */
 472 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 473 {
 474         struct nfs_server *server = NFS_SB(dentry->d_sb);
 475         unsigned char blockbits;
 476         unsigned long blockres;
 477         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 478         struct nfs_fsstat res;
 479         int error = -ENOMEM;
 480
 481         res.fattr = nfs_alloc_fattr();
 482         if (res.fattr == NULL)
 483                 goto out_err;
 484
 485         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 486         if (unlikely(error == -ESTALE)) {
 487                 struct dentry *pd_dentry;
 488
 489                 pd_dentry = dget_parent(dentry);
 490                 if (pd_dentry != NULL) {
 491                         nfs_zap_caches(pd_dentry->d_inode);
 492                         dput(pd_dentry);
 493                 }
 494         }
 495         nfs_free_fattr(res.fattr);
 496         if (error < 0)
 497                 goto out_err;
 498
 499         buf->f_type = NFS_SUPER_MAGIC;
 500
 501         /*
 502          * Current versions of glibc do not correctly handle the
 503          * case where f_frsize != f_bsize.  Eventually we want to
 504          * report the value of wtmult in this field.
 505          */
 506         buf->f_frsize = dentry->d_sb->s_blocksize;
 507
 508         /*
 509          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 510          * are reported in units of f_frsize.  Linux hasn't had
 511          * an f_frsize field in its statfs struct until recently,
 512          * thus historically Linux's sys_statfs reports these
 513          * fields in units of f_bsize.
 514          */
 515         buf->f_bsize = dentry->d_sb->s_blocksize;
 516         blockbits = dentry->d_sb->s_blocksize_bits;
 517         blockres = (1 << blockbits) - 1;
 518         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 519         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 520         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 521
 522         buf->f_files = res.tfiles;
 523         buf->f_ffree = res.afiles;
 524
 525         buf->f_namelen = server->namelen;
 526
 527         return 0;
 528
 529  out_err:
 530         dprintk("%s: statfs error = %d\n", __func__, -error);
 531         return error;
 532 }
 533 EXPORT_SYMBOL_GPL(nfs_statfs);
 534
 535 /*
 536  * Map the security flavour number to a name
 537  */
 538 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 539 {
 540         static const struct {
 541                 rpc_authflavor_t flavour;
 542                 const char *str;
 543         } sec_flavours[] = {
 544                 { RPC_AUTH_NULL, "null" },
 545                 { RPC_AUTH_UNIX, "sys" },
 546                 { RPC_AUTH_GSS_KRB5, "krb5" },
 547                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 548                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 549                 { RPC_AUTH_GSS_LKEY, "lkey" },
 550                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 551                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 552                 { RPC_AUTH_GSS_SPKM, "spkm" },
 553                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 554                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 555                 { UINT_MAX, "unknown" }
 556         };
 557         int i;
 558
 559         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 560                 if (sec_flavours[i].flavour == flavour)
 561                         break;
 562         }
 563         return sec_flavours[i].str;
 564 }
 565
 566 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 567                                   int showdefaults)
 568 {
 569         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 570
 571         seq_printf(m, ",mountproto=");
 572         switch (sap->sa_family) {
 573         case AF_INET:
 574                 switch (nfss->mountd_protocol) {
 575                 case IPPROTO_UDP:
 576                         seq_printf(m, RPCBIND_NETID_UDP);
 577                         break;
 578                 case IPPROTO_TCP:
 579                         seq_printf(m, RPCBIND_NETID_TCP);
 580                         break;
 581                 default:
 582                         if (showdefaults)
 583                                 seq_printf(m, "auto");
 584                 }
 585                 break;
 586         case AF_INET6:
 587                 switch (nfss->mountd_protocol) {
 588                 case IPPROTO_UDP:
 589                         seq_printf(m, RPCBIND_NETID_UDP6);
 590                         break;
 591                 case IPPROTO_TCP:
 592                         seq_printf(m, RPCBIND_NETID_TCP6);
 593                         break;
 594                 default:
 595                         if (showdefaults)
 596                                 seq_printf(m, "auto");
 597                 }
 598                 break;
 599         default:
 600                 if (showdefaults)
 601                         seq_printf(m, "auto");
 602         }
 603 }
 604
 605 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 606                                     int showdefaults)
 607 {
 608         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 609
 610         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 611                 return;
 612
 613         switch (sap->sa_family) {
 614         case AF_INET: {
 615                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 616                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 617                 break;
 618         }
 619         case AF_INET6: {
 620                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 621                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 622                 break;
 623         }
 624         default:
 625                 if (showdefaults)
 626                         seq_printf(m, ",mountaddr=unspecified");
 627         }
 628
 629         if (nfss->mountd_version || showdefaults)
 630                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 631         if ((nfss->mountd_port &&
 632                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 633                 showdefaults)
 634                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 635
 636         nfs_show_mountd_netid(m, nfss, showdefaults);
 637 }
 638
 639 #if IS_ENABLED(CONFIG_NFS_V4)
 640 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 641                                     int showdefaults)
 642 {
 643         struct nfs_client *clp = nfss->nfs_client;
 644
 645         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 646 }
 647 #else
 648 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 649                                     int showdefaults)
 650 {
 651 }
 652 #endif
 653
 654 static void nfs_show_nfs_version(struct seq_file *m,
 655                 unsigned int version,
 656                 unsigned int minorversion)
 657 {
 658         seq_printf(m, ",vers=%u", version);
 659         if (version == 4)
 660                 seq_printf(m, ".%u", minorversion);
 661 }
 662
 663 /*
 664  * Describe the mount options in force on this server representation
 665  */
 666 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 667                                    int showdefaults)
 668 {
 669         static const struct proc_nfs_info {
 670                 int flag;
 671                 const char *str;
 672                 const char *nostr;
 673         } nfs_info[] = {
 674                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 675                 { NFS_MOUNT_POSIX, ",posix", "" },
 676                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 677                 { NFS_MOUNT_NOAC, ",noac", "" },
 678                 { NFS_MOUNT_NONLM, ",nolock", "" },
 679                 { NFS_MOUNT_NOACL, ",noacl", "" },
 680                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 681                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 682                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 683                 { 0, NULL, NULL }
 684         };
 685         const struct proc_nfs_info *nfs_infop;
 686         struct nfs_client *clp = nfss->nfs_client;
 687         u32 version = clp->rpc_ops->version;
 688         int local_flock, local_fcntl;
 689
 690         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 691         seq_printf(m, ",rsize=%u", nfss->rsize);
 692         seq_printf(m, ",wsize=%u", nfss->wsize);
 693         if (nfss->bsize != 0)
 694                 seq_printf(m, ",bsize=%u", nfss->bsize);
 695         seq_printf(m, ",namlen=%u", nfss->namelen);
 696         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 697                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 698         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 699                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 700         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 701                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 702         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 703                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 704         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 705                 if (nfss->flags & nfs_infop->flag)
 706                         seq_puts(m, nfs_infop->str);
 707                 else
 708                         seq_puts(m, nfs_infop->nostr);
 709         }
 710         rcu_read_lock();
 711         seq_printf(m, ",proto=%s",
 712                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 713         rcu_read_unlock();
 714         if (version == 4) {
 715                 if (nfss->port != NFS_PORT)
 716                         seq_printf(m, ",port=%u", nfss->port);
 717         } else
 718                 if (nfss->port)
 719                         seq_printf(m, ",port=%u", nfss->port);
 720
 721         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 722         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 723         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 724
 725         if (version != 4)
 726                 nfs_show_mountd_options(m, nfss, showdefaults);
 727         else
 728                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 729
 730         if (nfss->options & NFS_OPTION_FSCACHE)
 731                 seq_printf(m, ",fsc");
 732
 733         if (nfss->options & NFS_OPTION_MIGRATION)
 734                 seq_printf(m, ",migration");
 735
 736         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 737                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 738                         seq_printf(m, ",lookupcache=none");
 739                 else
 740                         seq_printf(m, ",lookupcache=pos");
 741         }
 742
 743         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 744         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 745
 746         if (!local_flock && !local_fcntl)
 747                 seq_printf(m, ",local_lock=none");
 748         else if (local_flock && local_fcntl)
 749                 seq_printf(m, ",local_lock=all");
 750         else if (local_flock)
 751                 seq_printf(m, ",local_lock=flock");
 752         else
 753                 seq_printf(m, ",local_lock=posix");
 754 }
 755
 756 /*
 757  * Describe the mount options on this VFS mountpoint
 758  */
 759 int nfs_show_options(struct seq_file *m, struct dentry *root)
 760 {
 761         struct nfs_server *nfss = NFS_SB(root->d_sb);
 762
 763         nfs_show_mount_options(m, nfss, 0);
 764
 765         rcu_read_lock();
 766         seq_printf(m, ",addr=%s",
 767                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 768                                                         RPC_DISPLAY_ADDR));
 769         rcu_read_unlock();
 770
 771         return 0;
 772 }
 773 EXPORT_SYMBOL_GPL(nfs_show_options);
 774
 775 #if IS_ENABLED(CONFIG_NFS_V4)
 776 #ifdef CONFIG_NFS_V4_1
 777 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 778 {
 779         if (nfs4_has_session(server->nfs_client))
 780                 seq_printf(m, ",sessions");
 781 }
 782 #else
 783 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 784 #endif
 785 #endif
 786
 787 #ifdef CONFIG_NFS_V4_1
 788 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 789 {
 790         seq_printf(m, ",pnfs=");
 791         if (server->pnfs_curr_ld)
 792                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 793         else
 794                 seq_printf(m, "not configured");
 795 }
 796
 797 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 798 {
 799         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 800                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 801                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 802                            "date='%llu,%u'",
 803                            impl_id->name, impl_id->domain,
 804                            impl_id->date.seconds, impl_id->date.nseconds);
 805         }
 806 }
 807 #else
 808 #if IS_ENABLED(CONFIG_NFS_V4)
 809 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 810 {
 811 }
 812 #endif
 813 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 814 {
 815 }
 816 #endif
 817
 818 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 819 {
 820         char *page = (char *) __get_free_page(GFP_KERNEL);
 821         char *devname, *dummy;
 822         int err = 0;
 823         if (!page)
 824                 return -ENOMEM;
 825         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 826         if (IS_ERR(devname))
 827                 err = PTR_ERR(devname);
 828         else
 829                 seq_escape(m, devname, " \t\n\\");
 830         free_page((unsigned long)page);
 831         return err;
 832 }
 833 EXPORT_SYMBOL_GPL(nfs_show_devname);
 834
 835 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 836 {
 837         seq_puts(m, "/");
 838         return 0;
 839 }
 840 EXPORT_SYMBOL_GPL(nfs_show_path);
 841
 842 /*
 843  * Present statistical information for this VFS mountpoint
 844  */
 845 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 846 {
 847         int i, cpu;
 848         struct nfs_server *nfss = NFS_SB(root->d_sb);
 849         struct rpc_auth *auth = nfss->client->cl_auth;
 850         struct nfs_iostats totals = { };
 851
 852         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 853
 854         /*
 855          * Display all mount option settings
 856          */
 857         seq_printf(m, "\n\topts:\t");
 858         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 859         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 860         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 861         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 862         nfs_show_mount_options(m, nfss, 1);
 863
 864         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 865
 866         show_implementation_id(m, nfss);
 867
 868         seq_printf(m, "\n\tcaps:\t");
 869         seq_printf(m, "caps=0x%x", nfss->caps);
 870         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 871         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 872         seq_printf(m, ",bsize=%u", nfss->bsize);
 873         seq_printf(m, ",namlen=%u", nfss->namelen);
 874
 875 #if IS_ENABLED(CONFIG_NFS_V4)
 876         if (nfss->nfs_client->rpc_ops->version == 4) {
 877                 seq_printf(m, "\n\tnfsv4:\t");
 878                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 879                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 880                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 881                 show_sessions(m, nfss);
 882                 show_pnfs(m, nfss);
 883         }
 884 #endif
 885
 886         /*
 887          * Display security flavor in effect for this mount
 888          */
 889         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 890         if (auth->au_flavor)
 891                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 892
 893         /*
 894          * Display superblock I/O counters
 895          */
 896         for_each_possible_cpu(cpu) {
 897                 struct nfs_iostats *stats;
 898
 899                 preempt_disable();
 900                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 901
 902                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 903                         totals.events[i] += stats->events[i];
 904                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 905                         totals.bytes[i] += stats->bytes[i];
 906 #ifdef CONFIG_NFS_FSCACHE
 907                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 908                         totals.fscache[i] += stats->fscache[i];
 909 #endif
 910
 911                 preempt_enable();
 912         }
 913
 914         seq_printf(m, "\n\tevents:\t");
 915         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 916                 seq_printf(m, "%lu ", totals.events[i]);
 917         seq_printf(m, "\n\tbytes:\t");
 918         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 919                 seq_printf(m, "%Lu ", totals.bytes[i]);
 920 #ifdef CONFIG_NFS_FSCACHE
 921         if (nfss->options & NFS_OPTION_FSCACHE) {
 922                 seq_printf(m, "\n\tfsc:\t");
 923                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 924                         seq_printf(m, "%Lu ", totals.bytes[i]);
 925         }
 926 #endif
 927         seq_printf(m, "\n");
 928
 929         rpc_print_iostats(m, nfss->client);
 930
 931         return 0;
 932 }
 933 EXPORT_SYMBOL_GPL(nfs_show_stats);
 934
 935 /*
 936  * Begin unmount by attempting to remove all automounted mountpoints we added
 937  * in response to xdev traversals and referrals
 938  */
 939 void nfs_umount_begin(struct super_block *sb)
 940 {
 941         struct nfs_server *server;
 942         struct rpc_clnt *rpc;
 943
 944         server = NFS_SB(sb);
 945         /* -EIO all pending I/O */
 946         rpc = server->client_acl;
 947         if (!IS_ERR(rpc))
 948                 rpc_killall_tasks(rpc);
 949         rpc = server->client;
 950         if (!IS_ERR(rpc))
 951                 rpc_killall_tasks(rpc);
 952 }
 953 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 954
 955 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 956 {
 957         struct nfs_parsed_mount_data *data;
 958
 959         data = kzalloc(sizeof(*data), GFP_KERNEL);
 960         if (data) {
 961                 data->acregmin          = NFS_DEF_ACREGMIN;
 962                 data->acregmax          = NFS_DEF_ACREGMAX;
 963                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 964                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 965                 data->mount_server.port = NFS_UNSPEC_PORT;
 966                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 967                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 968                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 969                 data->auth_flavor_len   = 1;
 970                 data->minorversion      = 0;
 971                 data->need_mount        = true;
 972                 data->net               = current->nsproxy->net_ns;
 973                 security_init_mnt_opts(&data->lsm_opts);
 974         }
 975         return data;
 976 }
 977
 978 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 979 {
 980         if (data) {
 981                 kfree(data->client_address);
 982                 kfree(data->mount_server.hostname);
 983                 kfree(data->nfs_server.export_path);
 984                 kfree(data->nfs_server.hostname);
 985                 kfree(data->fscache_uniq);
 986                 security_free_mnt_opts(&data->lsm_opts);
 987                 kfree(data);
 988         }
 989 }
 990
 991 /*
 992  * Sanity-check a server address provided by the mount command.
 993  *
 994  * Address family must be initialized, and address must not be
 995  * the ANY address for that family.
 996  */
 997 static int nfs_verify_server_address(struct sockaddr *addr)
 998 {
 999         switch (addr->sa_family) {
1000         case AF_INET: {
1001                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
1002                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
1003         }
1004         case AF_INET6: {
1005                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
1006                 return !ipv6_addr_any(sa);
1007         }
1008         }
1009
1010         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
1011         return 0;
1012 }
1013
1014 /*
1015  * Select between a default port value and a user-specified port value.
1016  * If a zero value is set, then autobind will be used.
1017  */
1018 static void nfs_set_port(struct sockaddr *sap, int *port,
1019                                  const unsigned short default_port)
1020 {
1021         if (*port == NFS_UNSPEC_PORT)
1022                 *port = default_port;
1023
1024         rpc_set_port(sap, *port);
1025 }
1026
1027 /*
1028  * Sanity check the NFS transport protocol.
1029  *
1030  */
1031 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
1032 {
1033         switch (mnt->nfs_server.protocol) {
1034         case XPRT_TRANSPORT_UDP:
1035         case XPRT_TRANSPORT_TCP:
1036         case XPRT_TRANSPORT_RDMA:
1037                 break;
1038         default:
1039                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1040         }
1041 }
1042
1043 /*
1044  * For text based NFSv2/v3 mounts, the mount protocol transport default
1045  * settings should depend upon the specified NFS transport.
1046  */
1047 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1048 {
1049         nfs_validate_transport_protocol(mnt);
1050
1051         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1052             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1053                         return;
1054         switch (mnt->nfs_server.protocol) {
1055         case XPRT_TRANSPORT_UDP:
1056                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1057                 break;
1058         case XPRT_TRANSPORT_TCP:
1059         case XPRT_TRANSPORT_RDMA:
1060                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1061         }
1062 }
1063
1064 /*
1065  * Parse the value of the 'sec=' option.
1066  */
1067 static int nfs_parse_security_flavors(char *value,
1068                                       struct nfs_parsed_mount_data *mnt)
1069 {
1070         substring_t args[MAX_OPT_ARGS];
1071
1072         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1073
1074         switch (match_token(value, nfs_secflavor_tokens, args)) {
1075         case Opt_sec_none:
1076                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1077                 break;
1078         case Opt_sec_sys:
1079                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1080                 break;
1081         case Opt_sec_krb5:
1082                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1083                 break;
1084         case Opt_sec_krb5i:
1085                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1086                 break;
1087         case Opt_sec_krb5p:
1088                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1089                 break;
1090         case Opt_sec_lkey:
1091                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1092                 break;
1093         case Opt_sec_lkeyi:
1094                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1095                 break;
1096         case Opt_sec_lkeyp:
1097                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1098                 break;
1099         case Opt_sec_spkm:
1100                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1101                 break;
1102         case Opt_sec_spkmi:
1103                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1104                 break;
1105         case Opt_sec_spkmp:
1106                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1107                 break;
1108         default:
1109                 return 0;
1110         }
1111
1112         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1113         mnt->auth_flavor_len = 1;
1114         return 1;
1115 }
1116
1117 static int nfs_parse_version_string(char *string,
1118                 struct nfs_parsed_mount_data *mnt,
1119                 substring_t *args)
1120 {
1121         mnt->flags &= ~NFS_MOUNT_VER3;
1122         switch (match_token(string, nfs_vers_tokens, args)) {
1123         case Opt_vers_2:
1124                 mnt->version = 2;
1125                 break;
1126         case Opt_vers_3:
1127                 mnt->flags |= NFS_MOUNT_VER3;
1128                 mnt->version = 3;
1129                 break;
1130         case Opt_vers_4:
1131                 /* Backward compatibility option. In future,
1132                  * the mount program should always supply
1133                  * a NFSv4 minor version number.
1134                  */
1135                 mnt->version = 4;
1136                 break;
1137         case Opt_vers_4_0:
1138                 mnt->version = 4;
1139                 mnt->minorversion = 0;
1140                 break;
1141         case Opt_vers_4_1:
1142                 mnt->version = 4;
1143                 mnt->minorversion = 1;
1144                 break;
1145         default:
1146                 return 0;
1147         }
1148         return 1;
1149 }
1150
1151 static int nfs_get_option_str(substring_t args[], char **option)
1152 {
1153         kfree(*option);
1154         *option = match_strdup(args);
1155         return !*option;
1156 }
1157
1158 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1159 {
1160         int rc;
1161         char *string;
1162
1163         string = match_strdup(args);
1164         if (string == NULL)
1165                 return -ENOMEM;
1166         rc = kstrtoul(string, 10, option);
1167         kfree(string);
1168
1169         return rc;
1170 }
1171
1172 /*
1173  * Error-check and convert a string of mount options from user space into
1174  * a data structure.  The whole mount string is processed; bad options are
1175  * skipped as they are encountered.  If there were no errors, return 1;
1176  * otherwise return 0 (zero).
1177  */
1178 static int nfs_parse_mount_options(char *raw,
1179                                    struct nfs_parsed_mount_data *mnt)
1180 {
1181         char *p, *string, *secdata;
1182         int rc, sloppy = 0, invalid_option = 0;
1183         unsigned short protofamily = AF_UNSPEC;
1184         unsigned short mountfamily = AF_UNSPEC;
1185
1186         if (!raw) {
1187                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1188                 return 1;
1189         }
1190         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1191
1192         secdata = alloc_secdata();
1193         if (!secdata)
1194                 goto out_nomem;
1195
1196         rc = security_sb_copy_data(raw, secdata);
1197         if (rc)
1198                 goto out_security_failure;
1199
1200         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1201         if (rc)
1202                 goto out_security_failure;
1203
1204         free_secdata(secdata);
1205
1206         while ((p = strsep(&raw, ",")) != NULL) {
1207                 substring_t args[MAX_OPT_ARGS];
1208                 unsigned long option;
1209                 int token;
1210
1211                 if (!*p)
1212                         continue;
1213
1214                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1215
1216                 token = match_token(p, nfs_mount_option_tokens, args);
1217                 switch (token) {
1218
1219                 /*
1220                  * boolean options:  foo/nofoo
1221                  */
1222                 case Opt_soft:
1223                         mnt->flags |= NFS_MOUNT_SOFT;
1224                         break;
1225                 case Opt_hard:
1226                         mnt->flags &= ~NFS_MOUNT_SOFT;
1227                         break;
1228                 case Opt_posix:
1229                         mnt->flags |= NFS_MOUNT_POSIX;
1230                         break;
1231                 case Opt_noposix:
1232                         mnt->flags &= ~NFS_MOUNT_POSIX;
1233                         break;
1234                 case Opt_cto:
1235                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1236                         break;
1237                 case Opt_nocto:
1238                         mnt->flags |= NFS_MOUNT_NOCTO;
1239                         break;
1240                 case Opt_ac:
1241                         mnt->flags &= ~NFS_MOUNT_NOAC;
1242                         break;
1243                 case Opt_noac:
1244                         mnt->flags |= NFS_MOUNT_NOAC;
1245                         break;
1246                 case Opt_lock:
1247                         mnt->flags &= ~NFS_MOUNT_NONLM;
1248                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1249                                         NFS_MOUNT_LOCAL_FCNTL);
1250                         break;
1251                 case Opt_nolock:
1252                         mnt->flags |= NFS_MOUNT_NONLM;
1253                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1254                                        NFS_MOUNT_LOCAL_FCNTL);
1255                         break;
1256                 case Opt_udp:
1257                         mnt->flags &= ~NFS_MOUNT_TCP;
1258                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1259                         break;
1260                 case Opt_tcp:
1261                         mnt->flags |= NFS_MOUNT_TCP;
1262                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1263                         break;
1264                 case Opt_rdma:
1265                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1266                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1267                         xprt_load_transport(p);
1268                         break;
1269                 case Opt_acl:
1270                         mnt->flags &= ~NFS_MOUNT_NOACL;
1271                         break;
1272                 case Opt_noacl:
1273                         mnt->flags |= NFS_MOUNT_NOACL;
1274                         break;
1275                 case Opt_rdirplus:
1276                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1277                         break;
1278                 case Opt_nordirplus:
1279                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1280                         break;
1281                 case Opt_sharecache:
1282                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1283                         break;
1284                 case Opt_nosharecache:
1285                         mnt->flags |= NFS_MOUNT_UNSHARED;
1286                         break;
1287                 case Opt_resvport:
1288                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1289                         break;
1290                 case Opt_noresvport:
1291                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1292                         break;
1293                 case Opt_fscache:
1294                         mnt->options |= NFS_OPTION_FSCACHE;
1295                         kfree(mnt->fscache_uniq);
1296                         mnt->fscache_uniq = NULL;
1297                         break;
1298                 case Opt_nofscache:
1299                         mnt->options &= ~NFS_OPTION_FSCACHE;
1300                         kfree(mnt->fscache_uniq);
1301                         mnt->fscache_uniq = NULL;
1302                         break;
1303                 case Opt_migration:
1304                         mnt->options |= NFS_OPTION_MIGRATION;
1305                         break;
1306                 case Opt_nomigration:
1307                         mnt->options &= NFS_OPTION_MIGRATION;
1308                         break;
1309
1310                 /*
1311                  * options that take numeric values
1312                  */
1313                 case Opt_port:
1314                         if (nfs_get_option_ul(args, &option) ||
1315                             option > USHRT_MAX)
1316                                 goto out_invalid_value;
1317                         mnt->nfs_server.port = option;
1318                         break;
1319                 case Opt_rsize:
1320                         if (nfs_get_option_ul(args, &option))
1321                                 goto out_invalid_value;
1322                         mnt->rsize = option;
1323                         break;
1324                 case Opt_wsize:
1325                         if (nfs_get_option_ul(args, &option))
1326                                 goto out_invalid_value;
1327                         mnt->wsize = option;
1328                         break;
1329                 case Opt_bsize:
1330                         if (nfs_get_option_ul(args, &option))
1331                                 goto out_invalid_value;
1332                         mnt->bsize = option;
1333                         break;
1334                 case Opt_timeo:
1335                         if (nfs_get_option_ul(args, &option) || option == 0)
1336                                 goto out_invalid_value;
1337                         mnt->timeo = option;
1338                         break;
1339                 case Opt_retrans:
1340                         if (nfs_get_option_ul(args, &option) || option == 0)
1341                                 goto out_invalid_value;
1342                         mnt->retrans = option;
1343                         break;
1344                 case Opt_acregmin:
1345                         if (nfs_get_option_ul(args, &option))
1346                                 goto out_invalid_value;
1347                         mnt->acregmin = option;
1348                         break;
1349                 case Opt_acregmax:
1350                         if (nfs_get_option_ul(args, &option))
1351                                 goto out_invalid_value;
1352                         mnt->acregmax = option;
1353                         break;
1354                 case Opt_acdirmin:
1355                         if (nfs_get_option_ul(args, &option))
1356                                 goto out_invalid_value;
1357                         mnt->acdirmin = option;
1358                         break;
1359                 case Opt_acdirmax:
1360                         if (nfs_get_option_ul(args, &option))
1361                                 goto out_invalid_value;
1362                         mnt->acdirmax = option;
1363                         break;
1364                 case Opt_actimeo:
1365                         if (nfs_get_option_ul(args, &option))
1366                                 goto out_invalid_value;
1367                         mnt->acregmin = mnt->acregmax =
1368                         mnt->acdirmin = mnt->acdirmax = option;
1369                         break;
1370                 case Opt_namelen:
1371                         if (nfs_get_option_ul(args, &option))
1372                                 goto out_invalid_value;
1373                         mnt->namlen = option;
1374                         break;
1375                 case Opt_mountport:
1376                         if (nfs_get_option_ul(args, &option) ||
1377                             option > USHRT_MAX)
1378                                 goto out_invalid_value;
1379                         mnt->mount_server.port = option;
1380                         break;
1381                 case Opt_mountvers:
1382                         if (nfs_get_option_ul(args, &option) ||
1383                             option < NFS_MNT_VERSION ||
1384                             option > NFS_MNT3_VERSION)
1385                                 goto out_invalid_value;
1386                         mnt->mount_server.version = option;
1387                         break;
1388                 case Opt_minorversion:
1389                         if (nfs_get_option_ul(args, &option))
1390                                 goto out_invalid_value;
1391                         if (option > NFS4_MAX_MINOR_VERSION)
1392                                 goto out_invalid_value;
1393                         mnt->minorversion = option;
1394                         break;
1395
1396                 /*
1397                  * options that take text values
1398                  */
1399                 case Opt_nfsvers:
1400                         string = match_strdup(args);
1401                         if (string == NULL)
1402                                 goto out_nomem;
1403                         rc = nfs_parse_version_string(string, mnt, args);
1404                         kfree(string);
1405                         if (!rc)
1406                                 goto out_invalid_value;
1407                         break;
1408                 case Opt_sec:
1409                         string = match_strdup(args);
1410                         if (string == NULL)
1411                                 goto out_nomem;
1412                         rc = nfs_parse_security_flavors(string, mnt);
1413                         kfree(string);
1414                         if (!rc) {
1415                                 dfprintk(MOUNT, "NFS:   unrecognized "
1416                                                 "security flavor\n");
1417                                 return 0;
1418                         }
1419                         break;
1420                 case Opt_proto:
1421                         string = match_strdup(args);
1422                         if (string == NULL)
1423                                 goto out_nomem;
1424                         token = match_token(string,
1425                                             nfs_xprt_protocol_tokens, args);
1426
1427                         protofamily = AF_INET;
1428                         switch (token) {
1429                         case Opt_xprt_udp6:
1430                                 protofamily = AF_INET6;
1431                         case Opt_xprt_udp:
1432                                 mnt->flags &= ~NFS_MOUNT_TCP;
1433                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1434                                 break;
1435                         case Opt_xprt_tcp6:
1436                                 protofamily = AF_INET6;
1437                         case Opt_xprt_tcp:
1438                                 mnt->flags |= NFS_MOUNT_TCP;
1439                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1440                                 break;
1441                         case Opt_xprt_rdma:
1442                                 /* vector side protocols to TCP */
1443                                 mnt->flags |= NFS_MOUNT_TCP;
1444                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1445                                 xprt_load_transport(string);
1446                                 break;
1447                         default:
1448                                 dfprintk(MOUNT, "NFS:   unrecognized "
1449                                                 "transport protocol\n");
1450                                 kfree(string);
1451                                 return 0;
1452                         }
1453                         kfree(string);
1454                         break;
1455                 case Opt_mountproto:
1456                         string = match_strdup(args);
1457                         if (string == NULL)
1458                                 goto out_nomem;
1459                         token = match_token(string,
1460                                             nfs_xprt_protocol_tokens, args);
1461                         kfree(string);
1462
1463                         mountfamily = AF_INET;
1464                         switch (token) {
1465                         case Opt_xprt_udp6:
1466                                 mountfamily = AF_INET6;
1467                         case Opt_xprt_udp:
1468                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1469                                 break;
1470                         case Opt_xprt_tcp6:
1471                                 mountfamily = AF_INET6;
1472                         case Opt_xprt_tcp:
1473                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1474                                 break;
1475                         case Opt_xprt_rdma: /* not used for side protocols */
1476                         default:
1477                                 dfprintk(MOUNT, "NFS:   unrecognized "
1478                                                 "transport protocol\n");
1479                                 return 0;
1480                         }
1481                         break;
1482                 case Opt_addr:
1483                         string = match_strdup(args);
1484                         if (string == NULL)
1485                                 goto out_nomem;
1486                         mnt->nfs_server.addrlen =
1487                                 rpc_pton(mnt->net, string, strlen(string),
1488                                         (struct sockaddr *)
1489                                         &mnt->nfs_server.address,
1490                                         sizeof(mnt->nfs_server.address));
1491                         kfree(string);
1492                         if (mnt->nfs_server.addrlen == 0)
1493                                 goto out_invalid_address;
1494                         break;
1495                 case Opt_clientaddr:
1496                         if (nfs_get_option_str(args, &mnt->client_address))
1497                                 goto out_nomem;
1498                         break;
1499                 case Opt_mounthost:
1500                         if (nfs_get_option_str(args,
1501                                                &mnt->mount_server.hostname))
1502                                 goto out_nomem;
1503                         break;
1504                 case Opt_mountaddr:
1505                         string = match_strdup(args);
1506                         if (string == NULL)
1507                                 goto out_nomem;
1508                         mnt->mount_server.addrlen =
1509                                 rpc_pton(mnt->net, string, strlen(string),
1510                                         (struct sockaddr *)
1511                                         &mnt->mount_server.address,
1512                                         sizeof(mnt->mount_server.address));
1513                         kfree(string);
1514                         if (mnt->mount_server.addrlen == 0)
1515                                 goto out_invalid_address;
1516                         break;
1517                 case Opt_lookupcache:
1518                         string = match_strdup(args);
1519                         if (string == NULL)
1520                                 goto out_nomem;
1521                         token = match_token(string,
1522                                         nfs_lookupcache_tokens, args);
1523                         kfree(string);
1524                         switch (token) {
1525                                 case Opt_lookupcache_all:
1526                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1527                                         break;
1528                                 case Opt_lookupcache_positive:
1529                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1530                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1531                                         break;
1532                                 case Opt_lookupcache_none:
1533                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1534                                         break;
1535                                 default:
1536                                         dfprintk(MOUNT, "NFS:   invalid "
1537                                                         "lookupcache argument\n");
1538                                         return 0;
1539                         };
1540                         break;
1541                 case Opt_fscache_uniq:
1542                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1543                                 goto out_nomem;
1544                         mnt->options |= NFS_OPTION_FSCACHE;
1545                         break;
1546                 case Opt_local_lock:
1547                         string = match_strdup(args);
1548                         if (string == NULL)
1549                                 goto out_nomem;
1550                         token = match_token(string, nfs_local_lock_tokens,
1551                                         args);
1552                         kfree(string);
1553                         switch (token) {
1554                         case Opt_local_lock_all:
1555                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1556                                                NFS_MOUNT_LOCAL_FCNTL);
1557                                 break;
1558                         case Opt_local_lock_flock:
1559                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1560                                 break;
1561                         case Opt_local_lock_posix:
1562                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1563                                 break;
1564                         case Opt_local_lock_none:
1565                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1566                                                 NFS_MOUNT_LOCAL_FCNTL);
1567                                 break;
1568                         default:
1569                                 dfprintk(MOUNT, "NFS:   invalid "
1570                                                 "local_lock argument\n");
1571                                 return 0;
1572                         };
1573                         break;
1574
1575                 /*
1576                  * Special options
1577                  */
1578                 case Opt_sloppy:
1579                         sloppy = 1;
1580                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1581                         break;
1582                 case Opt_userspace:
1583                 case Opt_deprecated:
1584                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1585                                         "'%s'\n", p);
1586                         break;
1587
1588                 default:
1589                         invalid_option = 1;
1590                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1591                                         "'%s'\n", p);
1592                 }
1593         }
1594
1595         if (!sloppy && invalid_option)
1596                 return 0;
1597
1598         if (mnt->minorversion && mnt->version != 4)
1599                 goto out_minorversion_mismatch;
1600
1601         if (mnt->options & NFS_OPTION_MIGRATION &&
1602             mnt->version != 4 && mnt->minorversion != 0)
1603                 goto out_migration_misuse;
1604
1605         /*
1606          * verify that any proto=/mountproto= options match the address
1607          * families in the addr=/mountaddr= options.
1608          */
1609         if (protofamily != AF_UNSPEC &&
1610             protofamily != mnt->nfs_server.address.ss_family)
1611                 goto out_proto_mismatch;
1612
1613         if (mountfamily != AF_UNSPEC) {
1614                 if (mnt->mount_server.addrlen) {
1615                         if (mountfamily != mnt->mount_server.address.ss_family)
1616                                 goto out_mountproto_mismatch;
1617                 } else {
1618                         if (mountfamily != mnt->nfs_server.address.ss_family)
1619                                 goto out_mountproto_mismatch;
1620                 }
1621         }
1622
1623         return 1;
1624
1625 out_mountproto_mismatch:
1626         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1627                          "option\n");
1628         return 0;
1629 out_proto_mismatch:
1630         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1631         return 0;
1632 out_invalid_address:
1633         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1634         return 0;
1635 out_invalid_value:
1636         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1637         return 0;
1638 out_minorversion_mismatch:
1639         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1640                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1641         return 0;
1642 out_migration_misuse:
1643         printk(KERN_INFO
1644                 "NFS: 'migration' not supported for this NFS version\n");
1645         return 0;
1646 out_nomem:
1647         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1648         return 0;
1649 out_security_failure:
1650         free_secdata(secdata);
1651         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1652         return 0;
1653 }
1654
1655 /*
1656  * Match the requested auth flavors with the list returned by
1657  * the server.  Returns zero and sets the mount's authentication
1658  * flavor on success; returns -EACCES if server does not support
1659  * the requested flavor.
1660  */
1661 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1662                              struct nfs_mount_request *request)
1663 {
1664         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1665
1666         /*
1667          * Certain releases of Linux's mountd return an empty
1668          * flavor list.  To prevent behavioral regression with
1669          * these servers (ie. rejecting mounts that used to
1670          * succeed), revert to pre-2.6.32 behavior (no checking)
1671          * if the returned flavor list is empty.
1672          */
1673         if (server_authlist_len == 0)
1674                 return 0;
1675
1676         /*
1677          * We avoid sophisticated negotiating here, as there are
1678          * plenty of cases where we can get it wrong, providing
1679          * either too little or too much security.
1680          *
1681          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1682          * flavor listed first.  However, some servers list
1683          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1684          * preferred default, in args->auth_flavors[0] if user
1685          * didn't specify sec= mount option.
1686          */
1687         for (i = 0; i < args->auth_flavor_len; i++)
1688                 for (j = 0; j < server_authlist_len; j++)
1689                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1690                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1691                                         request->auth_flavs[j]);
1692                                 args->auth_flavors[0] = request->auth_flavs[j];
1693                                 return 0;
1694                         }
1695
1696         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1697         nfs_umount(request);
1698         return -EACCES;
1699 }
1700
1701 /*
1702  * Use the remote server's MOUNT service to request the NFS file handle
1703  * corresponding to the provided path.
1704  */
1705 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1706                              struct nfs_fh *root_fh)
1707 {
1708         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1709         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1710         struct nfs_mount_request request = {
1711                 .sap            = (struct sockaddr *)
1712                                                 &args->mount_server.address,
1713                 .dirpath        = args->nfs_server.export_path,
1714                 .protocol       = args->mount_server.protocol,
1715                 .fh             = root_fh,
1716                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1717                 .auth_flav_len  = &server_authlist_len,
1718                 .auth_flavs     = server_authlist,
1719                 .net            = args->net,
1720         };
1721         int status;
1722
1723         if (args->mount_server.version == 0) {
1724                 switch (args->version) {
1725                         default:
1726                                 args->mount_server.version = NFS_MNT3_VERSION;
1727                                 break;
1728                         case 2:
1729                                 args->mount_server.version = NFS_MNT_VERSION;
1730                 }
1731         }
1732         request.version = args->mount_server.version;
1733
1734         if (args->mount_server.hostname)
1735                 request.hostname = args->mount_server.hostname;
1736         else
1737                 request.hostname = args->nfs_server.hostname;
1738
1739         /*
1740          * Construct the mount server's address.
1741          */
1742         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1743                 memcpy(request.sap, &args->nfs_server.address,
1744                        args->nfs_server.addrlen);
1745                 args->mount_server.addrlen = args->nfs_server.addrlen;
1746         }
1747         request.salen = args->mount_server.addrlen;
1748         nfs_set_port(request.sap, &args->mount_server.port, 0);
1749
1750         /*
1751          * Now ask the mount server to map our export path
1752          * to a file handle.
1753          */
1754         status = nfs_mount(&request);
1755         if (status != 0) {
1756                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1757                                 request.hostname, status);
1758                 return status;
1759         }
1760
1761         /*
1762          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1763          */
1764         if (args->mount_server.version != NFS_MNT3_VERSION)
1765                 return 0;
1766         return nfs_walk_authlist(args, &request);
1767 }
1768
1769 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1770                              struct nfs_mount_info *mount_info,
1771                              struct nfs_subversion *nfs_mod)
1772 {
1773         int status;
1774         struct nfs_server *server;
1775
1776         if (mount_info->parsed->need_mount) {
1777                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1778                 if (status)
1779                         return ERR_PTR(status);
1780         }
1781
1782         /* Get a volume representation */
1783         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1784         if (IS_ERR(server))
1785                 return ERR_CAST(server);
1786
1787         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1788 }
1789 EXPORT_SYMBOL_GPL(nfs_try_mount);
1790
1791 /*
1792  * Split "dev_name" into "hostname:export_path".
1793  *
1794  * The leftmost colon demarks the split between the server's hostname
1795  * and the export path.  If the hostname starts with a left square
1796  * bracket, then it may contain colons.
1797  *
1798  * Note: caller frees hostname and export path, even on error.
1799  */
1800 static int nfs_parse_devname(const char *dev_name,
1801                              char **hostname, size_t maxnamlen,
1802                              char **export_path, size_t maxpathlen)
1803 {
1804         size_t len;
1805         char *end;
1806
1807         /* Is the host name protected with square brakcets? */
1808         if (*dev_name == '[') {
1809                 end = strchr(++dev_name, ']');
1810                 if (end == NULL || end[1] != ':')
1811                         goto out_bad_devname;
1812
1813                 len = end - dev_name;
1814                 end++;
1815         } else {
1816                 char *comma;
1817
1818                 end = strchr(dev_name, ':');
1819                 if (end == NULL)
1820                         goto out_bad_devname;
1821                 len = end - dev_name;
1822
1823                 /* kill possible hostname list: not supported */
1824                 comma = strchr(dev_name, ',');
1825                 if (comma != NULL && comma < end)
1826                         *comma = 0;
1827         }
1828
1829         if (len > maxnamlen)
1830                 goto out_hostname;
1831
1832         /* N.B. caller will free nfs_server.hostname in all cases */
1833         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1834         if (*hostname == NULL)
1835                 goto out_nomem;
1836         len = strlen(++end);
1837         if (len > maxpathlen)
1838                 goto out_path;
1839         *export_path = kstrndup(end, len, GFP_KERNEL);
1840         if (!*export_path)
1841                 goto out_nomem;
1842
1843         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1844         return 0;
1845
1846 out_bad_devname:
1847         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1848         return -EINVAL;
1849
1850 out_nomem:
1851         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1852         return -ENOMEM;
1853
1854 out_hostname:
1855         dfprintk(MOUNT, "NFS: server hostname too long\n");
1856         return -ENAMETOOLONG;
1857
1858 out_path:
1859         dfprintk(MOUNT, "NFS: export pathname too long\n");
1860         return -ENAMETOOLONG;
1861 }
1862
1863 /*
1864  * Validate the NFS2/NFS3 mount data
1865  * - fills in the mount root filehandle
1866  *
1867  * For option strings, user space handles the following behaviors:
1868  *
1869  * + DNS: mapping server host name to IP address ("addr=" option)
1870  *
1871  * + failure mode: how to behave if a mount request can't be handled
1872  *   immediately ("fg/bg" option)
1873  *
1874  * + retry: how often to retry a mount request ("retry=" option)
1875  *
1876  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1877  *   mountproto=tcp after mountproto=udp, and so on
1878  */
1879 static int nfs23_validate_mount_data(void *options,
1880                                      struct nfs_parsed_mount_data *args,
1881                                      struct nfs_fh *mntfh,
1882                                      const char *dev_name)
1883 {
1884         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1885         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1886
1887         if (data == NULL)
1888                 goto out_no_data;
1889
1890         args->version = NFS_DEFAULT_VERSION;
1891         switch (data->version) {
1892         case 1:
1893                 data->namlen = 0;
1894         case 2:
1895                 data->bsize = 0;
1896         case 3:
1897                 if (data->flags & NFS_MOUNT_VER3)
1898                         goto out_no_v3;
1899                 data->root.size = NFS2_FHSIZE;
1900                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1901         case 4:
1902                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1903                         goto out_no_sec;
1904         case 5:
1905                 memset(data->context, 0, sizeof(data->context));
1906         case 6:
1907                 if (data->flags & NFS_MOUNT_VER3) {
1908                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1909                                 goto out_invalid_fh;
1910                         mntfh->size = data->root.size;
1911                         args->version = 3;
1912                 } else {
1913                         mntfh->size = NFS2_FHSIZE;
1914                         args->version = 2;
1915                 }
1916
1917
1918                 memcpy(mntfh->data, data->root.data, mntfh->size);
1919                 if (mntfh->size < sizeof(mntfh->data))
1920                         memset(mntfh->data + mntfh->size, 0,
1921                                sizeof(mntfh->data) - mntfh->size);
1922
1923                 /*
1924                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1925                  * can deal with.
1926                  */
1927                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1928                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1929                 args->rsize             = data->rsize;
1930                 args->wsize             = data->wsize;
1931                 args->timeo             = data->timeo;
1932                 args->retrans           = data->retrans;
1933                 args->acregmin          = data->acregmin;
1934                 args->acregmax          = data->acregmax;
1935                 args->acdirmin          = data->acdirmin;
1936                 args->acdirmax          = data->acdirmax;
1937                 args->need_mount        = false;
1938
1939                 memcpy(sap, &data->addr, sizeof(data->addr));
1940                 args->nfs_server.addrlen = sizeof(data->addr);
1941                 args->nfs_server.port = ntohs(data->addr.sin_port);
1942                 if (!nfs_verify_server_address(sap))
1943                         goto out_no_address;
1944
1945                 if (!(data->flags & NFS_MOUNT_TCP))
1946                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1947                 /* N.B. caller will free nfs_server.hostname in all cases */
1948                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1949                 args->namlen            = data->namlen;
1950                 args->bsize             = data->bsize;
1951
1952                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1953                         args->auth_flavors[0] = data->pseudoflavor;
1954                 if (!args->nfs_server.hostname)
1955                         goto out_nomem;
1956
1957                 if (!(data->flags & NFS_MOUNT_NONLM))
1958                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1959                                          NFS_MOUNT_LOCAL_FCNTL);
1960                 else
1961                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1962                                         NFS_MOUNT_LOCAL_FCNTL);
1963                 /*
1964                  * The legacy version 6 binary mount data from userspace has a
1965                  * field used only to transport selinux information into the
1966                  * the kernel.  To continue to support that functionality we
1967                  * have a touch of selinux knowledge here in the NFS code. The
1968                  * userspace code converted context=blah to just blah so we are
1969                  * converting back to the full string selinux understands.
1970                  */
1971                 if (data->context[0]){
1972 #ifdef CONFIG_SECURITY_SELINUX
1973                         int rc;
1974                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1975                         if (!opts_str)
1976                                 return -ENOMEM;
1977                         strcpy(opts_str, "context=");
1978                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1979                         strcat(opts_str, &data->context[0]);
1980                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1981                         kfree(opts_str);
1982                         if (rc)
1983                                 return rc;
1984 #else
1985                         return -EINVAL;
1986 #endif
1987                 }
1988
1989                 break;
1990         default:
1991                 return NFS_TEXT_DATA;
1992         }
1993
1994 #if !IS_ENABLED(CONFIG_NFS_V3)
1995         if (args->version == 3)
1996                 goto out_v3_not_compiled;
1997 #endif /* !CONFIG_NFS_V3 */
1998
1999         return 0;
2000
2001 out_no_data:
2002         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2003         return -EINVAL;
2004
2005 out_no_v3:
2006         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2007                  data->version);
2008         return -EINVAL;
2009
2010 out_no_sec:
2011         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2012         return -EINVAL;
2013
2014 #if !IS_ENABLED(CONFIG_NFS_V3)
2015 out_v3_not_compiled:
2016         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2017         return -EPROTONOSUPPORT;
2018 #endif /* !CONFIG_NFS_V3 */
2019
2020 out_nomem:
2021         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2022         return -ENOMEM;
2023
2024 out_no_address:
2025         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2026         return -EINVAL;
2027
2028 out_invalid_fh:
2029         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2030         return -EINVAL;
2031 }
2032
2033 #if IS_ENABLED(CONFIG_NFS_V4)
2034 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2035                                    void *options,
2036                                    struct nfs_parsed_mount_data *args,
2037                                    struct nfs_fh *mntfh,
2038                                    const char *dev_name)
2039 {
2040         if (fs_type == &nfs_fs_type)
2041                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2042         return nfs4_validate_mount_data(options, args, dev_name);
2043 }
2044 #else
2045 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2046                                    void *options,
2047                                    struct nfs_parsed_mount_data *args,
2048                                    struct nfs_fh *mntfh,
2049                                    const char *dev_name)
2050 {
2051         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2052 }
2053 #endif
2054
2055 static int nfs_validate_text_mount_data(void *options,
2056                                         struct nfs_parsed_mount_data *args,
2057                                         const char *dev_name)
2058 {
2059         int port = 0;
2060         int max_namelen = PAGE_SIZE;
2061         int max_pathlen = NFS_MAXPATHLEN;
2062         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2063
2064         if (nfs_parse_mount_options((char *)options, args) == 0)
2065                 return -EINVAL;
2066
2067         if (!nfs_verify_server_address(sap))
2068                 goto out_no_address;
2069
2070         if (args->version == 4) {
2071 #if IS_ENABLED(CONFIG_NFS_V4)
2072                 port = NFS_PORT;
2073                 max_namelen = NFS4_MAXNAMLEN;
2074                 max_pathlen = NFS4_MAXPATHLEN;
2075                 nfs_validate_transport_protocol(args);
2076                 nfs4_validate_mount_flags(args);
2077 #else
2078                 goto out_v4_not_compiled;
2079 #endif /* CONFIG_NFS_V4 */
2080         } else
2081                 nfs_set_mount_transport_protocol(args);
2082
2083         nfs_set_port(sap, &args->nfs_server.port, port);
2084
2085         if (args->auth_flavor_len > 1)
2086                 goto out_bad_auth;
2087
2088         return nfs_parse_devname(dev_name,
2089                                    &args->nfs_server.hostname,
2090                                    max_namelen,
2091                                    &args->nfs_server.export_path,
2092                                    max_pathlen);
2093
2094 #if !IS_ENABLED(CONFIG_NFS_V4)
2095 out_v4_not_compiled:
2096         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2097         return -EPROTONOSUPPORT;
2098 #endif /* !CONFIG_NFS_V4 */
2099
2100 out_no_address:
2101         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2102         return -EINVAL;
2103
2104 out_bad_auth:
2105         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2106         return -EINVAL;
2107 }
2108
2109 static int
2110 nfs_compare_remount_data(struct nfs_server *nfss,
2111                          struct nfs_parsed_mount_data *data)
2112 {
2113         if (data->flags != nfss->flags ||
2114             data->rsize != nfss->rsize ||
2115             data->wsize != nfss->wsize ||
2116             data->retrans != nfss->client->cl_timeout->to_retries ||
2117             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2118             data->acregmin != nfss->acregmin / HZ ||
2119             data->acregmax != nfss->acregmax / HZ ||
2120             data->acdirmin != nfss->acdirmin / HZ ||
2121             data->acdirmax != nfss->acdirmax / HZ ||
2122             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2123             data->nfs_server.port != nfss->port ||
2124             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2125             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2126                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2127                 return -EINVAL;
2128
2129         return 0;
2130 }
2131
2132 int
2133 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2134 {
2135         int error;
2136         struct nfs_server *nfss = sb->s_fs_info;
2137         struct nfs_parsed_mount_data *data;
2138         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2139         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2140         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2141
2142         /*
2143          * Userspace mount programs that send binary options generally send
2144          * them populated with default values. We have no way to know which
2145          * ones were explicitly specified. Fall back to legacy behavior and
2146          * just return success.
2147          */
2148         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2149             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2150                                            options->version <= 6))))
2151                 return 0;
2152
2153         data = kzalloc(sizeof(*data), GFP_KERNEL);
2154         if (data == NULL)
2155                 return -ENOMEM;
2156
2157         /* fill out struct with values from existing mount */
2158         data->flags = nfss->flags;
2159         data->rsize = nfss->rsize;
2160         data->wsize = nfss->wsize;
2161         data->retrans = nfss->client->cl_timeout->to_retries;
2162         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2163         data->acregmin = nfss->acregmin / HZ;
2164         data->acregmax = nfss->acregmax / HZ;
2165         data->acdirmin = nfss->acdirmin / HZ;
2166         data->acdirmax = nfss->acdirmax / HZ;
2167         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2168         data->nfs_server.port = nfss->port;
2169         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2170         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2171                 data->nfs_server.addrlen);
2172
2173         /* overwrite those values with any that were specified */
2174         error = nfs_parse_mount_options((char *)options, data);
2175         if (error < 0)
2176                 goto out;
2177
2178         /*
2179          * noac is a special case. It implies -o sync, but that's not
2180          * necessarily reflected in the mtab options. do_remount_sb
2181          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2182          * remount options, so we have to explicitly reset it.
2183          */
2184         if (data->flags & NFS_MOUNT_NOAC)
2185                 *flags |= MS_SYNCHRONOUS;
2186
2187         /* compare new mount options with old ones */
2188         error = nfs_compare_remount_data(nfss, data);
2189 out:
2190         kfree(data);
2191         return error;
2192 }
2193 EXPORT_SYMBOL_GPL(nfs_remount);
2194
2195 /*
2196  * Initialise the common bits of the superblock
2197  */
2198 inline void nfs_initialise_sb(struct super_block *sb)
2199 {
2200         struct nfs_server *server = NFS_SB(sb);
2201
2202         sb->s_magic = NFS_SUPER_MAGIC;
2203
2204         /* We probably want something more informative here */
2205         snprintf(sb->s_id, sizeof(sb->s_id),
2206                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2207
2208         if (sb->s_blocksize == 0)
2209                 sb->s_blocksize = nfs_block_bits(server->wsize,
2210                                                  &sb->s_blocksize_bits);
2211
2212         sb->s_bdi = &server->backing_dev_info;
2213
2214         nfs_super_set_maxbytes(sb, server->maxfilesize);
2215 }
2216
2217 /*
2218  * Finish setting up an NFS2/3 superblock
2219  */
2220 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2221 {
2222         struct nfs_parsed_mount_data *data = mount_info->parsed;
2223         struct nfs_server *server = NFS_SB(sb);
2224
2225         sb->s_blocksize_bits = 0;
2226         sb->s_blocksize = 0;
2227         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2228         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2229         if (data && data->bsize)
2230                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2231
2232         if (server->nfs_client->rpc_ops->version != 2) {
2233                 /* The VFS shouldn't apply the umask to mode bits. We will do
2234                  * so ourselves when necessary.
2235                  */
2236                 sb->s_flags |= MS_POSIXACL;
2237                 sb->s_time_gran = 1;
2238         }
2239
2240         nfs_initialise_sb(sb);
2241 }
2242 EXPORT_SYMBOL_GPL(nfs_fill_super);
2243
2244 /*
2245  * Finish setting up a cloned NFS2/3/4 superblock
2246  */
2247 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2248 {
2249         const struct super_block *old_sb = mount_info->cloned->sb;
2250         struct nfs_server *server = NFS_SB(sb);
2251
2252         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2253         sb->s_blocksize = old_sb->s_blocksize;
2254         sb->s_maxbytes = old_sb->s_maxbytes;
2255         sb->s_xattr = old_sb->s_xattr;
2256         sb->s_op = old_sb->s_op;
2257         sb->s_time_gran = 1;
2258
2259         if (server->nfs_client->rpc_ops->version != 2) {
2260                 /* The VFS shouldn't apply the umask to mode bits. We will do
2261                  * so ourselves when necessary.
2262                  */
2263                 sb->s_flags |= MS_POSIXACL;
2264         }
2265
2266         nfs_initialise_sb(sb);
2267 }
2268
2269 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2270 {
2271         const struct nfs_server *a = s->s_fs_info;
2272         const struct rpc_clnt *clnt_a = a->client;
2273         const struct rpc_clnt *clnt_b = b->client;
2274
2275         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2276                 goto Ebusy;
2277         if (a->nfs_client != b->nfs_client)
2278                 goto Ebusy;
2279         if (a->flags != b->flags)
2280                 goto Ebusy;
2281         if (a->wsize != b->wsize)
2282                 goto Ebusy;
2283         if (a->rsize != b->rsize)
2284                 goto Ebusy;
2285         if (a->acregmin != b->acregmin)
2286                 goto Ebusy;
2287         if (a->acregmax != b->acregmax)
2288                 goto Ebusy;
2289         if (a->acdirmin != b->acdirmin)
2290                 goto Ebusy;
2291         if (a->acdirmax != b->acdirmax)
2292                 goto Ebusy;
2293         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2294                 goto Ebusy;
2295         return 1;
2296 Ebusy:
2297         return 0;
2298 }
2299
2300 struct nfs_sb_mountdata {
2301         struct nfs_server *server;
2302         int mntflags;
2303 };
2304
2305 static int nfs_set_super(struct super_block *s, void *data)
2306 {
2307         struct nfs_sb_mountdata *sb_mntdata = data;
2308         struct nfs_server *server = sb_mntdata->server;
2309         int ret;
2310
2311         s->s_flags = sb_mntdata->mntflags;
2312         s->s_fs_info = server;
2313         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2314         ret = set_anon_super(s, server);
2315         if (ret == 0)
2316                 server->s_dev = s->s_dev;
2317         return ret;
2318 }
2319
2320 static int nfs_compare_super_address(struct nfs_server *server1,
2321                                      struct nfs_server *server2)
2322 {
2323         struct sockaddr *sap1, *sap2;
2324
2325         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2326         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2327
2328         if (sap1->sa_family != sap2->sa_family)
2329                 return 0;
2330
2331         switch (sap1->sa_family) {
2332         case AF_INET: {
2333                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2334                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2335                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2336                         return 0;
2337                 if (sin1->sin_port != sin2->sin_port)
2338                         return 0;
2339                 break;
2340         }
2341         case AF_INET6: {
2342                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2343                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2344                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2345                         return 0;
2346                 if (sin1->sin6_port != sin2->sin6_port)
2347                         return 0;
2348                 break;
2349         }
2350         default:
2351                 return 0;
2352         }
2353
2354         return 1;
2355 }
2356
2357 static int nfs_compare_super(struct super_block *sb, void *data)
2358 {
2359         struct nfs_sb_mountdata *sb_mntdata = data;
2360         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2361         int mntflags = sb_mntdata->mntflags;
2362
2363         if (!nfs_compare_super_address(old, server))
2364                 return 0;
2365         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2366         if (old->flags & NFS_MOUNT_UNSHARED)
2367                 return 0;
2368         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2369                 return 0;
2370         return nfs_compare_mount_options(sb, server, mntflags);
2371 }
2372
2373 #ifdef CONFIG_NFS_FSCACHE
2374 static void nfs_get_cache_cookie(struct super_block *sb,
2375                                  struct nfs_parsed_mount_data *parsed,
2376                                  struct nfs_clone_mount *cloned)
2377 {
2378         struct nfs_server *nfss = NFS_SB(sb);
2379         char *uniq = NULL;
2380         int ulen = 0;
2381
2382         nfss->fscache_key = NULL;
2383         nfss->fscache = NULL;
2384
2385         if (parsed) {
2386                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2387                         return;
2388                 if (parsed->fscache_uniq) {
2389                         uniq = parsed->fscache_uniq;
2390                         ulen = strlen(parsed->fscache_uniq);
2391                 }
2392         } else if (cloned) {
2393                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2394                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2395                         return;
2396                 if (mnt_s->fscache_key) {
2397                         uniq = mnt_s->fscache_key->key.uniquifier;
2398                         ulen = mnt_s->fscache_key->key.uniq_len;
2399                 };
2400         } else
2401                 return;
2402
2403         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2404 }
2405 #else
2406 static void nfs_get_cache_cookie(struct super_block *sb,
2407                                  struct nfs_parsed_mount_data *parsed,
2408                                  struct nfs_clone_mount *cloned)
2409 {
2410 }
2411 #endif
2412
2413 static int nfs_bdi_register(struct nfs_server *server)
2414 {
2415         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2416 }
2417
2418 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2419                         struct nfs_mount_info *mount_info)
2420 {
2421         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2422 }
2423 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2424
2425 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2426                           struct nfs_mount_info *mount_info)
2427 {
2428         /* clone any lsm security options from the parent to the new sb */
2429         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2430         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2431                 return -ESTALE;
2432         return 0;
2433 }
2434 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2435
2436 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2437                                    int flags, const char *dev_name,
2438                                    struct nfs_mount_info *mount_info,
2439                                    struct nfs_subversion *nfs_mod)
2440 {
2441         struct super_block *s;
2442         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2443         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2444         struct nfs_sb_mountdata sb_mntdata = {
2445                 .mntflags = flags,
2446                 .server = server,
2447         };
2448         int error;
2449
2450         if (server->flags & NFS_MOUNT_UNSHARED)
2451                 compare_super = NULL;
2452
2453         /* -o noac implies -o sync */
2454         if (server->flags & NFS_MOUNT_NOAC)
2455                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2456
2457         /* Get a superblock - note that we may end up sharing one that already exists */
2458         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2459         if (IS_ERR(s)) {
2460                 mntroot = ERR_CAST(s);
2461                 goto out_err_nosb;
2462         }
2463
2464         if (s->s_fs_info != server) {
2465                 nfs_free_server(server);
2466                 server = NULL;
2467         } else {
2468                 error = nfs_bdi_register(server);
2469                 if (error) {
2470                         mntroot = ERR_PTR(error);
2471                         goto error_splat_bdi;
2472                 }
2473         }
2474
2475         if (!s->s_root) {
2476                 /* initial superblock/root creation */
2477                 mount_info->fill_super(s, mount_info);
2478                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2479         }
2480
2481         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2482         if (IS_ERR(mntroot))
2483                 goto error_splat_super;
2484
2485         error = mount_info->set_security(s, mntroot, mount_info);
2486         if (error)
2487                 goto error_splat_root;
2488
2489         s->s_flags |= MS_ACTIVE;
2490
2491 out:
2492         return mntroot;
2493
2494 out_err_nosb:
2495         nfs_free_server(server);
2496         goto out;
2497
2498 error_splat_root:
2499         dput(mntroot);
2500         mntroot = ERR_PTR(error);
2501 error_splat_super:
2502         if (server && !s->s_root)
2503                 bdi_unregister(&server->backing_dev_info);
2504 error_splat_bdi:
2505         deactivate_locked_super(s);
2506         goto out;
2507 }
2508 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2509
2510 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2511         int flags, const char *dev_name, void *raw_data)
2512 {
2513         struct nfs_mount_info mount_info = {
2514                 .fill_super = nfs_fill_super,
2515                 .set_security = nfs_set_sb_security,
2516         };
2517         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2518         struct nfs_subversion *nfs_mod;
2519         int error;
2520
2521         mount_info.parsed = nfs_alloc_parsed_mount_data();
2522         mount_info.mntfh = nfs_alloc_fhandle();
2523         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2524                 goto out;
2525
2526         /* Validate the mount data */
2527         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2528         if (error == NFS_TEXT_DATA)
2529                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2530         if (error < 0) {
2531                 mntroot = ERR_PTR(error);
2532                 goto out;
2533         }
2534
2535         nfs_mod = get_nfs_version(mount_info.parsed->version);
2536         if (IS_ERR(nfs_mod)) {
2537                 mntroot = ERR_CAST(nfs_mod);
2538                 goto out;
2539         }
2540
2541         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2542
2543         put_nfs_version(nfs_mod);
2544 out:
2545         nfs_free_parsed_mount_data(mount_info.parsed);
2546         nfs_free_fhandle(mount_info.mntfh);
2547         return mntroot;
2548 }
2549 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2550
2551 /*
2552  * Ensure that we unregister the bdi before kill_anon_super
2553  * releases the device name
2554  */
2555 void nfs_put_super(struct super_block *s)
2556 {
2557         struct nfs_server *server = NFS_SB(s);
2558
2559         bdi_unregister(&server->backing_dev_info);
2560 }
2561 EXPORT_SYMBOL_GPL(nfs_put_super);
2562
2563 /*
2564  * Destroy an NFS2/3 superblock
2565  */
2566 void nfs_kill_super(struct super_block *s)
2567 {
2568         struct nfs_server *server = NFS_SB(s);
2569
2570         kill_anon_super(s);
2571         nfs_fscache_release_super_cookie(s);
2572         nfs_free_server(server);
2573 }
2574 EXPORT_SYMBOL_GPL(nfs_kill_super);
2575
2576 /*
2577  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2578  */
2579 static struct dentry *
2580 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2581                 const char *dev_name, void *raw_data)
2582 {
2583         struct nfs_clone_mount *data = raw_data;
2584         struct nfs_mount_info mount_info = {
2585                 .fill_super = nfs_clone_super,
2586                 .set_security = nfs_clone_sb_security,
2587                 .cloned = data,
2588         };
2589         struct nfs_server *server;
2590         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2591         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2592         int error;
2593
2594         dprintk("--> nfs_xdev_mount_common()\n");
2595
2596         mount_info.mntfh = mount_info.cloned->fh;
2597
2598         /* create a new volume representation */
2599         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2600         if (IS_ERR(server)) {
2601                 error = PTR_ERR(server);
2602                 goto out_err;
2603         }
2604
2605         mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, nfs_mod);
2606         dprintk("<-- nfs_xdev_mount_common() = 0\n");
2607 out:
2608         return mntroot;
2609
2610 out_err:
2611         dprintk("<-- nfs_xdev_mount_common() = %d [error]\n", error);
2612         goto out;
2613 }
2614
2615 #if IS_ENABLED(CONFIG_NFS_V4)
2616
2617 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2618 {
2619         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2620                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2621 }
2622
2623 /*
2624  * Validate NFSv4 mount options
2625  */
2626 static int nfs4_validate_mount_data(void *options,
2627                                     struct nfs_parsed_mount_data *args,
2628                                     const char *dev_name)
2629 {
2630         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2631         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2632         char *c;
2633
2634         if (data == NULL)
2635                 goto out_no_data;
2636
2637         args->version = 4;
2638
2639         switch (data->version) {
2640         case 1:
2641                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2642                         goto out_no_address;
2643                 if (data->host_addrlen == 0)
2644                         goto out_no_address;
2645                 args->nfs_server.addrlen = data->host_addrlen;
2646                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2647                         return -EFAULT;
2648                 if (!nfs_verify_server_address(sap))
2649                         goto out_no_address;
2650                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2651
2652                 if (data->auth_flavourlen) {
2653                         if (data->auth_flavourlen > 1)
2654                                 goto out_inval_auth;
2655                         if (copy_from_user(&args->auth_flavors[0],
2656                                            data->auth_flavours,
2657                                            sizeof(args->auth_flavors[0])))
2658                                 return -EFAULT;
2659                 }
2660
2661                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2662                 if (IS_ERR(c))
2663                         return PTR_ERR(c);
2664                 args->nfs_server.hostname = c;
2665
2666                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2667                 if (IS_ERR(c))
2668                         return PTR_ERR(c);
2669                 args->nfs_server.export_path = c;
2670                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2671
2672                 c = strndup_user(data->client_addr.data, 16);
2673                 if (IS_ERR(c))
2674                         return PTR_ERR(c);
2675                 args->client_address = c;
2676
2677                 /*
2678                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2679                  * can deal with.
2680                  */
2681
2682                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2683                 args->rsize     = data->rsize;
2684                 args->wsize     = data->wsize;
2685                 args->timeo     = data->timeo;
2686                 args->retrans   = data->retrans;
2687                 args->acregmin  = data->acregmin;
2688                 args->acregmax  = data->acregmax;
2689                 args->acdirmin  = data->acdirmin;
2690                 args->acdirmax  = data->acdirmax;
2691                 args->nfs_server.protocol = data->proto;
2692                 nfs_validate_transport_protocol(args);
2693
2694                 break;
2695         default:
2696                 return NFS_TEXT_DATA;
2697         }
2698
2699         return 0;
2700
2701 out_no_data:
2702         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2703         return -EINVAL;
2704
2705 out_inval_auth:
2706         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2707                  data->auth_flavourlen);
2708         return -EINVAL;
2709
2710 out_no_address:
2711         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2712         return -EINVAL;
2713 }
2714
2715 /*
2716  * NFS v4 module parameters need to stay in the
2717  * NFS client for backwards compatibility
2718  */
2719 unsigned int nfs_callback_set_tcpport;
2720 unsigned short nfs_callback_tcpport;
2721 /* Default cache timeout is 10 minutes */
2722 unsigned int nfs_idmap_cache_timeout = 600;
2723 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2724 bool nfs4_disable_idmapping = true;
2725 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2726 unsigned short send_implementation_id = 1;
2727 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2728
2729 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2730 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2731 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2732 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2733 EXPORT_SYMBOL_GPL(max_session_slots);
2734 EXPORT_SYMBOL_GPL(send_implementation_id);
2735 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2736
2737 #define NFS_CALLBACK_MAXPORTNR (65535U)
2738
2739 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2740 {
2741         unsigned long num;
2742         int ret;
2743
2744         if (!val)
2745                 return -EINVAL;
2746         ret = kstrtoul(val, 0, &num);
2747         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2748                 return -EINVAL;
2749         *((unsigned int *)kp->arg) = num;
2750         return 0;
2751 }
2752 static struct kernel_param_ops param_ops_portnr = {
2753         .set = param_set_portnr,
2754         .get = param_get_uint,
2755 };
2756 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2757
2758 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2759 module_param(nfs_idmap_cache_timeout, int, 0644);
2760 module_param(nfs4_disable_idmapping, bool, 0644);
2761 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2762                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2763 MODULE_PARM_DESC(nfs4_disable_idmapping,
2764                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2765 module_param(max_session_slots, ushort, 0644);
2766 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2767                 "requests the client will negotiate");
2768 module_param(send_implementation_id, ushort, 0644);
2769 MODULE_PARM_DESC(send_implementation_id,
2770                 "Send implementation ID with NFSv4.1 exchange_id");
2771 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2772 MODULE_ALIAS("nfs4");
2773
2774 #endif /* CONFIG_NFS_V4 */