fs/nfs/super.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/fs/nfs/super.c
   4  *
   5  *  Copyright (C) 1992  Rick Sladkey
   6  *
   7  *  nfs superblock handling functions
   8  *
   9  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
  10  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  11  *
  12  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  13  *  J.S.Peatfield@damtp.cam.ac.uk
  14  *
  15  *  Split from inode.c by David Howells <dhowells@redhat.com>
  16  *
  17  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  18  *   particular server are held in the same superblock
  19  * - NFS superblocks can have several effective roots to the dentry tree
  20  * - directory type roots are spliced into the tree when a path from one root reaches the root
  21  *   of another (see nfs_lookup())
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26
  27 #include <linux/time.h>
  28 #include <linux/kernel.h>
  29 #include <linux/mm.h>
  30 #include <linux/string.h>
  31 #include <linux/stat.h>
  32 #include <linux/errno.h>
  33 #include <linux/unistd.h>
  34 #include <linux/sunrpc/clnt.h>
  35 #include <linux/sunrpc/addr.h>
  36 #include <linux/sunrpc/stats.h>
  37 #include <linux/sunrpc/metrics.h>
  38 #include <linux/sunrpc/xprtsock.h>
  39 #include <linux/sunrpc/xprtrdma.h>
  40 #include <linux/nfs_fs.h>
  41 #include <linux/nfs_mount.h>
  42 #include <linux/nfs4_mount.h>
  43 #include <linux/lockd/bind.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/mount.h>
  46 #include <linux/namei.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56 #include <linux/nsproxy.h>
  57 #include <linux/rcupdate.h>
  58
  59 #include <linux/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_softerr, 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_softerr, "softerr" },
 130         { Opt_hard, "hard" },
 131         { Opt_deprecated, "intr" },
 132         { Opt_deprecated, "nointr" },
 133         { Opt_posix, "posix" },
 134         { Opt_noposix, "noposix" },
 135         { Opt_cto, "cto" },
 136         { Opt_nocto, "nocto" },
 137         { Opt_ac, "ac" },
 138         { Opt_noac, "noac" },
 139         { Opt_lock, "lock" },
 140         { Opt_nolock, "nolock" },
 141         { Opt_udp, "udp" },
 142         { Opt_tcp, "tcp" },
 143         { Opt_rdma, "rdma" },
 144         { Opt_acl, "acl" },
 145         { Opt_noacl, "noacl" },
 146         { Opt_rdirplus, "rdirplus" },
 147         { Opt_nordirplus, "nordirplus" },
 148         { Opt_sharecache, "sharecache" },
 149         { Opt_nosharecache, "nosharecache" },
 150         { Opt_resvport, "resvport" },
 151         { Opt_noresvport, "noresvport" },
 152         { Opt_fscache, "fsc" },
 153         { Opt_nofscache, "nofsc" },
 154         { Opt_migration, "migration" },
 155         { Opt_nomigration, "nomigration" },
 156
 157         { Opt_port, "port=%s" },
 158         { Opt_rsize, "rsize=%s" },
 159         { Opt_wsize, "wsize=%s" },
 160         { Opt_bsize, "bsize=%s" },
 161         { Opt_timeo, "timeo=%s" },
 162         { Opt_retrans, "retrans=%s" },
 163         { Opt_acregmin, "acregmin=%s" },
 164         { Opt_acregmax, "acregmax=%s" },
 165         { Opt_acdirmin, "acdirmin=%s" },
 166         { Opt_acdirmax, "acdirmax=%s" },
 167         { Opt_actimeo, "actimeo=%s" },
 168         { Opt_namelen, "namlen=%s" },
 169         { Opt_mountport, "mountport=%s" },
 170         { Opt_mountvers, "mountvers=%s" },
 171         { Opt_minorversion, "minorversion=%s" },
 172
 173         { Opt_nfsvers, "nfsvers=%s" },
 174         { Opt_nfsvers, "vers=%s" },
 175
 176         { Opt_sec, "sec=%s" },
 177         { Opt_proto, "proto=%s" },
 178         { Opt_mountproto, "mountproto=%s" },
 179         { Opt_addr, "addr=%s" },
 180         { Opt_clientaddr, "clientaddr=%s" },
 181         { Opt_mounthost, "mounthost=%s" },
 182         { Opt_mountaddr, "mountaddr=%s" },
 183
 184         { Opt_lookupcache, "lookupcache=%s" },
 185         { Opt_fscache_uniq, "fsc=%s" },
 186         { Opt_local_lock, "local_lock=%s" },
 187
 188         /* The following needs to be listed after all other options */
 189         { Opt_nfsvers, "v%s" },
 190
 191         { Opt_err, NULL }
 192 };
 193
 194 enum {
 195         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 196         Opt_xprt_rdma6,
 197
 198         Opt_xprt_err
 199 };
 200
 201 static const match_table_t nfs_xprt_protocol_tokens = {
 202         { Opt_xprt_udp, "udp" },
 203         { Opt_xprt_udp6, "udp6" },
 204         { Opt_xprt_tcp, "tcp" },
 205         { Opt_xprt_tcp6, "tcp6" },
 206         { Opt_xprt_rdma, "rdma" },
 207         { Opt_xprt_rdma6, "rdma6" },
 208
 209         { Opt_xprt_err, NULL }
 210 };
 211
 212 enum {
 213         Opt_sec_none, Opt_sec_sys,
 214         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 215         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 216         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 217
 218         Opt_sec_err
 219 };
 220
 221 static const match_table_t nfs_secflavor_tokens = {
 222         { Opt_sec_none, "none" },
 223         { Opt_sec_none, "null" },
 224         { Opt_sec_sys, "sys" },
 225
 226         { Opt_sec_krb5, "krb5" },
 227         { Opt_sec_krb5i, "krb5i" },
 228         { Opt_sec_krb5p, "krb5p" },
 229
 230         { Opt_sec_lkey, "lkey" },
 231         { Opt_sec_lkeyi, "lkeyi" },
 232         { Opt_sec_lkeyp, "lkeyp" },
 233
 234         { Opt_sec_spkm, "spkm3" },
 235         { Opt_sec_spkmi, "spkm3i" },
 236         { Opt_sec_spkmp, "spkm3p" },
 237
 238         { Opt_sec_err, NULL }
 239 };
 240
 241 enum {
 242         Opt_lookupcache_all, Opt_lookupcache_positive,
 243         Opt_lookupcache_none,
 244
 245         Opt_lookupcache_err
 246 };
 247
 248 static match_table_t nfs_lookupcache_tokens = {
 249         { Opt_lookupcache_all, "all" },
 250         { Opt_lookupcache_positive, "pos" },
 251         { Opt_lookupcache_positive, "positive" },
 252         { Opt_lookupcache_none, "none" },
 253
 254         { Opt_lookupcache_err, NULL }
 255 };
 256
 257 enum {
 258         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 259         Opt_local_lock_none,
 260
 261         Opt_local_lock_err
 262 };
 263
 264 static match_table_t nfs_local_lock_tokens = {
 265         { Opt_local_lock_all, "all" },
 266         { Opt_local_lock_flock, "flock" },
 267         { Opt_local_lock_posix, "posix" },
 268         { Opt_local_lock_none, "none" },
 269
 270         { Opt_local_lock_err, NULL }
 271 };
 272
 273 enum {
 274         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 275         Opt_vers_4_1, Opt_vers_4_2,
 276
 277         Opt_vers_err
 278 };
 279
 280 static match_table_t nfs_vers_tokens = {
 281         { Opt_vers_2, "2" },
 282         { Opt_vers_3, "3" },
 283         { Opt_vers_4, "4" },
 284         { Opt_vers_4_0, "4.0" },
 285         { Opt_vers_4_1, "4.1" },
 286         { Opt_vers_4_2, "4.2" },
 287
 288         { Opt_vers_err, NULL }
 289 };
 290
 291 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 292                 int flags, const char *dev_name, void *raw_data);
 293
 294 struct file_system_type nfs_fs_type = {
 295         .owner          = THIS_MODULE,
 296         .name           = "nfs",
 297         .mount          = nfs_fs_mount,
 298         .kill_sb        = nfs_kill_super,
 299         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 300 };
 301 MODULE_ALIAS_FS("nfs");
 302 EXPORT_SYMBOL_GPL(nfs_fs_type);
 303
 304 struct file_system_type nfs_xdev_fs_type = {
 305         .owner          = THIS_MODULE,
 306         .name           = "nfs",
 307         .mount          = nfs_xdev_mount,
 308         .kill_sb        = nfs_kill_super,
 309         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 310 };
 311
 312 const struct super_operations nfs_sops = {
 313         .alloc_inode    = nfs_alloc_inode,
 314         .free_inode     = nfs_free_inode,
 315         .write_inode    = nfs_write_inode,
 316         .drop_inode     = nfs_drop_inode,
 317         .statfs         = nfs_statfs,
 318         .evict_inode    = nfs_evict_inode,
 319         .umount_begin   = nfs_umount_begin,
 320         .show_options   = nfs_show_options,
 321         .show_devname   = nfs_show_devname,
 322         .show_path      = nfs_show_path,
 323         .show_stats     = nfs_show_stats,
 324         .remount_fs     = nfs_remount,
 325 };
 326 EXPORT_SYMBOL_GPL(nfs_sops);
 327
 328 #if IS_ENABLED(CONFIG_NFS_V4)
 329 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 330 static int nfs4_validate_mount_data(void *options,
 331         struct nfs_parsed_mount_data *args, const char *dev_name);
 332
 333 struct file_system_type nfs4_fs_type = {
 334         .owner          = THIS_MODULE,
 335         .name           = "nfs4",
 336         .mount          = nfs_fs_mount,
 337         .kill_sb        = nfs_kill_super,
 338         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 339 };
 340 MODULE_ALIAS_FS("nfs4");
 341 MODULE_ALIAS("nfs4");
 342 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 343
 344 static int __init register_nfs4_fs(void)
 345 {
 346         return register_filesystem(&nfs4_fs_type);
 347 }
 348
 349 static void unregister_nfs4_fs(void)
 350 {
 351         unregister_filesystem(&nfs4_fs_type);
 352 }
 353 #else
 354 static int __init register_nfs4_fs(void)
 355 {
 356         return 0;
 357 }
 358
 359 static void unregister_nfs4_fs(void)
 360 {
 361 }
 362 #endif
 363
 364 static struct shrinker acl_shrinker = {
 365         .count_objects  = nfs_access_cache_count,
 366         .scan_objects   = nfs_access_cache_scan,
 367         .seeks          = DEFAULT_SEEKS,
 368 };
 369
 370 /*
 371  * Register the NFS filesystems
 372  */
 373 int __init register_nfs_fs(void)
 374 {
 375         int ret;
 376
 377         ret = register_filesystem(&nfs_fs_type);
 378         if (ret < 0)
 379                 goto error_0;
 380
 381         ret = register_nfs4_fs();
 382         if (ret < 0)
 383                 goto error_1;
 384
 385         ret = nfs_register_sysctl();
 386         if (ret < 0)
 387                 goto error_2;
 388         ret = register_shrinker(&acl_shrinker);
 389         if (ret < 0)
 390                 goto error_3;
 391         return 0;
 392 error_3:
 393         nfs_unregister_sysctl();
 394 error_2:
 395         unregister_nfs4_fs();
 396 error_1:
 397         unregister_filesystem(&nfs_fs_type);
 398 error_0:
 399         return ret;
 400 }
 401
 402 /*
 403  * Unregister the NFS filesystems
 404  */
 405 void __exit unregister_nfs_fs(void)
 406 {
 407         unregister_shrinker(&acl_shrinker);
 408         nfs_unregister_sysctl();
 409         unregister_nfs4_fs();
 410         unregister_filesystem(&nfs_fs_type);
 411 }
 412
 413 bool nfs_sb_active(struct super_block *sb)
 414 {
 415         struct nfs_server *server = NFS_SB(sb);
 416
 417         if (!atomic_inc_not_zero(&sb->s_active))
 418                 return false;
 419         if (atomic_inc_return(&server->active) != 1)
 420                 atomic_dec(&sb->s_active);
 421         return true;
 422 }
 423 EXPORT_SYMBOL_GPL(nfs_sb_active);
 424
 425 void nfs_sb_deactive(struct super_block *sb)
 426 {
 427         struct nfs_server *server = NFS_SB(sb);
 428
 429         if (atomic_dec_and_test(&server->active))
 430                 deactivate_super(sb);
 431 }
 432 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 433
 434 /*
 435  * Deliver file system statistics to userspace
 436  */
 437 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 438 {
 439         struct nfs_server *server = NFS_SB(dentry->d_sb);
 440         unsigned char blockbits;
 441         unsigned long blockres;
 442         struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 443         struct nfs_fsstat res;
 444         int error = -ENOMEM;
 445
 446         res.fattr = nfs_alloc_fattr();
 447         if (res.fattr == NULL)
 448                 goto out_err;
 449
 450         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 451         if (unlikely(error == -ESTALE)) {
 452                 struct dentry *pd_dentry;
 453
 454                 pd_dentry = dget_parent(dentry);
 455                 if (pd_dentry != NULL) {
 456                         nfs_zap_caches(d_inode(pd_dentry));
 457                         dput(pd_dentry);
 458                 }
 459         }
 460         nfs_free_fattr(res.fattr);
 461         if (error < 0)
 462                 goto out_err;
 463
 464         buf->f_type = NFS_SUPER_MAGIC;
 465
 466         /*
 467          * Current versions of glibc do not correctly handle the
 468          * case where f_frsize != f_bsize.  Eventually we want to
 469          * report the value of wtmult in this field.
 470          */
 471         buf->f_frsize = dentry->d_sb->s_blocksize;
 472
 473         /*
 474          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 475          * are reported in units of f_frsize.  Linux hasn't had
 476          * an f_frsize field in its statfs struct until recently,
 477          * thus historically Linux's sys_statfs reports these
 478          * fields in units of f_bsize.
 479          */
 480         buf->f_bsize = dentry->d_sb->s_blocksize;
 481         blockbits = dentry->d_sb->s_blocksize_bits;
 482         blockres = (1 << blockbits) - 1;
 483         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 484         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 485         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 486
 487         buf->f_files = res.tfiles;
 488         buf->f_ffree = res.afiles;
 489
 490         buf->f_namelen = server->namelen;
 491
 492         return 0;
 493
 494  out_err:
 495         dprintk("%s: statfs error = %d\n", __func__, -error);
 496         return error;
 497 }
 498 EXPORT_SYMBOL_GPL(nfs_statfs);
 499
 500 /*
 501  * Map the security flavour number to a name
 502  */
 503 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 504 {
 505         static const struct {
 506                 rpc_authflavor_t flavour;
 507                 const char *str;
 508         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 509                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 510                 { RPC_AUTH_NULL, "null" },
 511                 { RPC_AUTH_UNIX, "sys" },
 512                 { RPC_AUTH_GSS_KRB5, "krb5" },
 513                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 514                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 515                 { RPC_AUTH_GSS_LKEY, "lkey" },
 516                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 517                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 518                 { RPC_AUTH_GSS_SPKM, "spkm" },
 519                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 520                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 521                 { UINT_MAX, "unknown" }
 522         };
 523         int i;
 524
 525         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 526                 if (sec_flavours[i].flavour == flavour)
 527                         break;
 528         }
 529         return sec_flavours[i].str;
 530 }
 531
 532 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 533                                   int showdefaults)
 534 {
 535         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 536         char *proto = NULL;
 537
 538         switch (sap->sa_family) {
 539         case AF_INET:
 540                 switch (nfss->mountd_protocol) {
 541                 case IPPROTO_UDP:
 542                         proto = RPCBIND_NETID_UDP;
 543                         break;
 544                 case IPPROTO_TCP:
 545                         proto = RPCBIND_NETID_TCP;
 546                         break;
 547                 }
 548                 break;
 549         case AF_INET6:
 550                 switch (nfss->mountd_protocol) {
 551                 case IPPROTO_UDP:
 552                         proto = RPCBIND_NETID_UDP6;
 553                         break;
 554                 case IPPROTO_TCP:
 555                         proto = RPCBIND_NETID_TCP6;
 556                         break;
 557                 }
 558                 break;
 559         }
 560         if (proto || showdefaults)
 561                 seq_printf(m, ",mountproto=%s", proto ?: "auto");
 562 }
 563
 564 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 565                                     int showdefaults)
 566 {
 567         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 568
 569         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 570                 return;
 571
 572         switch (sap->sa_family) {
 573         case AF_INET: {
 574                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 575                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 576                 break;
 577         }
 578         case AF_INET6: {
 579                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 580                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 581                 break;
 582         }
 583         default:
 584                 if (showdefaults)
 585                         seq_printf(m, ",mountaddr=unspecified");
 586         }
 587
 588         if (nfss->mountd_version || showdefaults)
 589                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 590         if ((nfss->mountd_port &&
 591                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 592                 showdefaults)
 593                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 594
 595         nfs_show_mountd_netid(m, nfss, showdefaults);
 596 }
 597
 598 #if IS_ENABLED(CONFIG_NFS_V4)
 599 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 600                                     int showdefaults)
 601 {
 602         struct nfs_client *clp = nfss->nfs_client;
 603
 604         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 605 }
 606 #else
 607 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 608                                     int showdefaults)
 609 {
 610 }
 611 #endif
 612
 613 static void nfs_show_nfs_version(struct seq_file *m,
 614                 unsigned int version,
 615                 unsigned int minorversion)
 616 {
 617         seq_printf(m, ",vers=%u", version);
 618         if (version == 4)
 619                 seq_printf(m, ".%u", minorversion);
 620 }
 621
 622 /*
 623  * Describe the mount options in force on this server representation
 624  */
 625 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 626                                    int showdefaults)
 627 {
 628         static const struct proc_nfs_info {
 629                 int flag;
 630                 const char *str;
 631                 const char *nostr;
 632         } nfs_info[] = {
 633                 { NFS_MOUNT_SOFT, ",soft", "" },
 634                 { NFS_MOUNT_SOFTERR, ",softerr", "" },
 635                 { NFS_MOUNT_POSIX, ",posix", "" },
 636                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 637                 { NFS_MOUNT_NOAC, ",noac", "" },
 638                 { NFS_MOUNT_NONLM, ",nolock", "" },
 639                 { NFS_MOUNT_NOACL, ",noacl", "" },
 640                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 641                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 642                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 643                 { 0, NULL, NULL }
 644         };
 645         const struct proc_nfs_info *nfs_infop;
 646         struct nfs_client *clp = nfss->nfs_client;
 647         u32 version = clp->rpc_ops->version;
 648         int local_flock, local_fcntl;
 649
 650         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 651         seq_printf(m, ",rsize=%u", nfss->rsize);
 652         seq_printf(m, ",wsize=%u", nfss->wsize);
 653         if (nfss->bsize != 0)
 654                 seq_printf(m, ",bsize=%u", nfss->bsize);
 655         seq_printf(m, ",namlen=%u", nfss->namelen);
 656         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 657                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 658         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 659                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 660         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 661                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 662         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 663                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 664         if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
 665                         seq_puts(m, ",hard");
 666         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 667                 if (nfss->flags & nfs_infop->flag)
 668                         seq_puts(m, nfs_infop->str);
 669                 else
 670                         seq_puts(m, nfs_infop->nostr);
 671         }
 672         rcu_read_lock();
 673         seq_printf(m, ",proto=%s",
 674                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 675         rcu_read_unlock();
 676         if (version == 4) {
 677                 if (nfss->port != NFS_PORT)
 678                         seq_printf(m, ",port=%u", nfss->port);
 679         } else
 680                 if (nfss->port)
 681                         seq_printf(m, ",port=%u", nfss->port);
 682
 683         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 684         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 685         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 686
 687         if (version != 4)
 688                 nfs_show_mountd_options(m, nfss, showdefaults);
 689         else
 690                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 691
 692         if (nfss->options & NFS_OPTION_FSCACHE)
 693                 seq_printf(m, ",fsc");
 694
 695         if (nfss->options & NFS_OPTION_MIGRATION)
 696                 seq_printf(m, ",migration");
 697
 698         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 699                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 700                         seq_printf(m, ",lookupcache=none");
 701                 else
 702                         seq_printf(m, ",lookupcache=pos");
 703         }
 704
 705         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 706         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 707
 708         if (!local_flock && !local_fcntl)
 709                 seq_printf(m, ",local_lock=none");
 710         else if (local_flock && local_fcntl)
 711                 seq_printf(m, ",local_lock=all");
 712         else if (local_flock)
 713                 seq_printf(m, ",local_lock=flock");
 714         else
 715                 seq_printf(m, ",local_lock=posix");
 716 }
 717
 718 /*
 719  * Describe the mount options on this VFS mountpoint
 720  */
 721 int nfs_show_options(struct seq_file *m, struct dentry *root)
 722 {
 723         struct nfs_server *nfss = NFS_SB(root->d_sb);
 724
 725         nfs_show_mount_options(m, nfss, 0);
 726
 727         rcu_read_lock();
 728         seq_printf(m, ",addr=%s",
 729                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 730                                                         RPC_DISPLAY_ADDR));
 731         rcu_read_unlock();
 732
 733         return 0;
 734 }
 735 EXPORT_SYMBOL_GPL(nfs_show_options);
 736
 737 #if IS_ENABLED(CONFIG_NFS_V4)
 738 #ifdef CONFIG_NFS_V4_1
 739 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 740 {
 741         if (nfs4_has_session(server->nfs_client))
 742                 seq_printf(m, ",sessions");
 743 }
 744 #else
 745 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 746 #endif
 747 #endif
 748
 749 #ifdef CONFIG_NFS_V4_1
 750 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 751 {
 752         seq_printf(m, ",pnfs=");
 753         if (server->pnfs_curr_ld)
 754                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 755         else
 756                 seq_printf(m, "not configured");
 757 }
 758
 759 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 760 {
 761         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 762                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 763                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 764                            "date='%llu,%u'",
 765                            impl_id->name, impl_id->domain,
 766                            impl_id->date.seconds, impl_id->date.nseconds);
 767         }
 768 }
 769 #else
 770 #if IS_ENABLED(CONFIG_NFS_V4)
 771 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 772 {
 773 }
 774 #endif
 775 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 776 {
 777 }
 778 #endif
 779
 780 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 781 {
 782         char *page = (char *) __get_free_page(GFP_KERNEL);
 783         char *devname, *dummy;
 784         int err = 0;
 785         if (!page)
 786                 return -ENOMEM;
 787         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 788         if (IS_ERR(devname))
 789                 err = PTR_ERR(devname);
 790         else
 791                 seq_escape(m, devname, " \t\n\\");
 792         free_page((unsigned long)page);
 793         return err;
 794 }
 795 EXPORT_SYMBOL_GPL(nfs_show_devname);
 796
 797 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 798 {
 799         seq_puts(m, "/");
 800         return 0;
 801 }
 802 EXPORT_SYMBOL_GPL(nfs_show_path);
 803
 804 /*
 805  * Present statistical information for this VFS mountpoint
 806  */
 807 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 808 {
 809         int i, cpu;
 810         struct nfs_server *nfss = NFS_SB(root->d_sb);
 811         struct rpc_auth *auth = nfss->client->cl_auth;
 812         struct nfs_iostats totals = { };
 813
 814         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 815
 816         /*
 817          * Display all mount option settings
 818          */
 819         seq_printf(m, "\n\topts:\t");
 820         seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
 821         seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
 822         seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
 823         seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
 824         nfs_show_mount_options(m, nfss, 1);
 825
 826         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 827
 828         show_implementation_id(m, nfss);
 829
 830         seq_printf(m, "\n\tcaps:\t");
 831         seq_printf(m, "caps=0x%x", nfss->caps);
 832         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 833         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 834         seq_printf(m, ",bsize=%u", nfss->bsize);
 835         seq_printf(m, ",namlen=%u", nfss->namelen);
 836
 837 #if IS_ENABLED(CONFIG_NFS_V4)
 838         if (nfss->nfs_client->rpc_ops->version == 4) {
 839                 seq_printf(m, "\n\tnfsv4:\t");
 840                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 841                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 842                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 843                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 844                 show_sessions(m, nfss);
 845                 show_pnfs(m, nfss);
 846         }
 847 #endif
 848
 849         /*
 850          * Display security flavor in effect for this mount
 851          */
 852         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 853         if (auth->au_flavor)
 854                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 855
 856         /*
 857          * Display superblock I/O counters
 858          */
 859         for_each_possible_cpu(cpu) {
 860                 struct nfs_iostats *stats;
 861
 862                 preempt_disable();
 863                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 864
 865                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 866                         totals.events[i] += stats->events[i];
 867                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 868                         totals.bytes[i] += stats->bytes[i];
 869 #ifdef CONFIG_NFS_FSCACHE
 870                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 871                         totals.fscache[i] += stats->fscache[i];
 872 #endif
 873
 874                 preempt_enable();
 875         }
 876
 877         seq_printf(m, "\n\tevents:\t");
 878         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 879                 seq_printf(m, "%lu ", totals.events[i]);
 880         seq_printf(m, "\n\tbytes:\t");
 881         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 882                 seq_printf(m, "%Lu ", totals.bytes[i]);
 883 #ifdef CONFIG_NFS_FSCACHE
 884         if (nfss->options & NFS_OPTION_FSCACHE) {
 885                 seq_printf(m, "\n\tfsc:\t");
 886                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 887                         seq_printf(m, "%Lu ", totals.fscache[i]);
 888         }
 889 #endif
 890         seq_printf(m, "\n");
 891
 892         rpc_clnt_show_stats(m, nfss->client);
 893
 894         return 0;
 895 }
 896 EXPORT_SYMBOL_GPL(nfs_show_stats);
 897
 898 /*
 899  * Begin unmount by attempting to remove all automounted mountpoints we added
 900  * in response to xdev traversals and referrals
 901  */
 902 void nfs_umount_begin(struct super_block *sb)
 903 {
 904         struct nfs_server *server;
 905         struct rpc_clnt *rpc;
 906
 907         server = NFS_SB(sb);
 908         /* -EIO all pending I/O */
 909         rpc = server->client_acl;
 910         if (!IS_ERR(rpc))
 911                 rpc_killall_tasks(rpc);
 912         rpc = server->client;
 913         if (!IS_ERR(rpc))
 914                 rpc_killall_tasks(rpc);
 915 }
 916 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 917
 918 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 919 {
 920         struct nfs_parsed_mount_data *data;
 921
 922         data = kzalloc(sizeof(*data), GFP_KERNEL);
 923         if (data) {
 924                 data->timeo             = NFS_UNSPEC_TIMEO;
 925                 data->retrans           = NFS_UNSPEC_RETRANS;
 926                 data->acregmin          = NFS_DEF_ACREGMIN;
 927                 data->acregmax          = NFS_DEF_ACREGMAX;
 928                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 929                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 930                 data->mount_server.port = NFS_UNSPEC_PORT;
 931                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 932                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 933                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 934                 data->minorversion      = 0;
 935                 data->need_mount        = true;
 936                 data->net               = current->nsproxy->net_ns;
 937                 data->lsm_opts          = NULL;
 938         }
 939         return data;
 940 }
 941
 942 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 943 {
 944         if (data) {
 945                 kfree(data->client_address);
 946                 kfree(data->mount_server.hostname);
 947                 kfree(data->nfs_server.export_path);
 948                 kfree(data->nfs_server.hostname);
 949                 kfree(data->fscache_uniq);
 950                 security_free_mnt_opts(&data->lsm_opts);
 951                 kfree(data);
 952         }
 953 }
 954
 955 /*
 956  * Sanity-check a server address provided by the mount command.
 957  *
 958  * Address family must be initialized, and address must not be
 959  * the ANY address for that family.
 960  */
 961 static int nfs_verify_server_address(struct sockaddr *addr)
 962 {
 963         switch (addr->sa_family) {
 964         case AF_INET: {
 965                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 966                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 967         }
 968         case AF_INET6: {
 969                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 970                 return !ipv6_addr_any(sa);
 971         }
 972         }
 973
 974         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 975         return 0;
 976 }
 977
 978 /*
 979  * Select between a default port value and a user-specified port value.
 980  * If a zero value is set, then autobind will be used.
 981  */
 982 static void nfs_set_port(struct sockaddr *sap, int *port,
 983                                  const unsigned short default_port)
 984 {
 985         if (*port == NFS_UNSPEC_PORT)
 986                 *port = default_port;
 987
 988         rpc_set_port(sap, *port);
 989 }
 990
 991 /*
 992  * Sanity check the NFS transport protocol.
 993  *
 994  */
 995 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 996 {
 997         switch (mnt->nfs_server.protocol) {
 998         case XPRT_TRANSPORT_UDP:
 999         case XPRT_TRANSPORT_TCP:
1000         case XPRT_TRANSPORT_RDMA:
1001                 break;
1002         default:
1003                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1004         }
1005 }
1006
1007 /*
1008  * For text based NFSv2/v3 mounts, the mount protocol transport default
1009  * settings should depend upon the specified NFS transport.
1010  */
1011 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1012 {
1013         nfs_validate_transport_protocol(mnt);
1014
1015         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1016             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1017                         return;
1018         switch (mnt->nfs_server.protocol) {
1019         case XPRT_TRANSPORT_UDP:
1020                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1021                 break;
1022         case XPRT_TRANSPORT_TCP:
1023         case XPRT_TRANSPORT_RDMA:
1024                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1025         }
1026 }
1027
1028 /*
1029  * Add 'flavor' to 'auth_info' if not already present.
1030  * Returns true if 'flavor' ends up in the list, false otherwise
1031  */
1032 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1033                               rpc_authflavor_t flavor)
1034 {
1035         unsigned int i;
1036         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1037
1038         /* make sure this flavor isn't already in the list */
1039         for (i = 0; i < auth_info->flavor_len; i++) {
1040                 if (flavor == auth_info->flavors[i])
1041                         return true;
1042         }
1043
1044         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1045                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1046                 return false;
1047         }
1048
1049         auth_info->flavors[auth_info->flavor_len++] = flavor;
1050         return true;
1051 }
1052
1053 /*
1054  * Return true if 'match' is in auth_info or auth_info is empty.
1055  * Return false otherwise.
1056  */
1057 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1058                          rpc_authflavor_t match)
1059 {
1060         int i;
1061
1062         if (!auth_info->flavor_len)
1063                 return true;
1064
1065         for (i = 0; i < auth_info->flavor_len; i++) {
1066                 if (auth_info->flavors[i] == match)
1067                         return true;
1068         }
1069         return false;
1070 }
1071 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1072
1073 /*
1074  * Parse the value of the 'sec=' option.
1075  */
1076 static int nfs_parse_security_flavors(char *value,
1077                                       struct nfs_parsed_mount_data *mnt)
1078 {
1079         substring_t args[MAX_OPT_ARGS];
1080         rpc_authflavor_t pseudoflavor;
1081         char *p;
1082
1083         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1084
1085         while ((p = strsep(&value, ":")) != NULL) {
1086                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1087                 case Opt_sec_none:
1088                         pseudoflavor = RPC_AUTH_NULL;
1089                         break;
1090                 case Opt_sec_sys:
1091                         pseudoflavor = RPC_AUTH_UNIX;
1092                         break;
1093                 case Opt_sec_krb5:
1094                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1095                         break;
1096                 case Opt_sec_krb5i:
1097                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1098                         break;
1099                 case Opt_sec_krb5p:
1100                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1101                         break;
1102                 case Opt_sec_lkey:
1103                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1104                         break;
1105                 case Opt_sec_lkeyi:
1106                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1107                         break;
1108                 case Opt_sec_lkeyp:
1109                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1110                         break;
1111                 case Opt_sec_spkm:
1112                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1113                         break;
1114                 case Opt_sec_spkmi:
1115                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1116                         break;
1117                 case Opt_sec_spkmp:
1118                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1119                         break;
1120                 default:
1121                         dfprintk(MOUNT,
1122                                  "NFS: sec= option '%s' not recognized\n", p);
1123                         return 0;
1124                 }
1125
1126                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1127                         return 0;
1128         }
1129
1130         return 1;
1131 }
1132
1133 static int nfs_parse_version_string(char *string,
1134                 struct nfs_parsed_mount_data *mnt,
1135                 substring_t *args)
1136 {
1137         mnt->flags &= ~NFS_MOUNT_VER3;
1138         switch (match_token(string, nfs_vers_tokens, args)) {
1139         case Opt_vers_2:
1140                 mnt->version = 2;
1141                 break;
1142         case Opt_vers_3:
1143                 mnt->flags |= NFS_MOUNT_VER3;
1144                 mnt->version = 3;
1145                 break;
1146         case Opt_vers_4:
1147                 /* Backward compatibility option. In future,
1148                  * the mount program should always supply
1149                  * a NFSv4 minor version number.
1150                  */
1151                 mnt->version = 4;
1152                 break;
1153         case Opt_vers_4_0:
1154                 mnt->version = 4;
1155                 mnt->minorversion = 0;
1156                 break;
1157         case Opt_vers_4_1:
1158                 mnt->version = 4;
1159                 mnt->minorversion = 1;
1160                 break;
1161         case Opt_vers_4_2:
1162                 mnt->version = 4;
1163                 mnt->minorversion = 2;
1164                 break;
1165         default:
1166                 return 0;
1167         }
1168         return 1;
1169 }
1170
1171 static int nfs_get_option_str(substring_t args[], char **option)
1172 {
1173         kfree(*option);
1174         *option = match_strdup(args);
1175         return !*option;
1176 }
1177
1178 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1179 {
1180         int rc;
1181         char *string;
1182
1183         string = match_strdup(args);
1184         if (string == NULL)
1185                 return -ENOMEM;
1186         rc = kstrtoul(string, 10, option);
1187         kfree(string);
1188
1189         return rc;
1190 }
1191
1192 static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1193                 unsigned long l_bound, unsigned long u_bound)
1194 {
1195         int ret;
1196
1197         ret = nfs_get_option_ul(args, option);
1198         if (ret != 0)
1199                 return ret;
1200         if (*option < l_bound || *option > u_bound)
1201                 return -ERANGE;
1202         return 0;
1203 }
1204
1205 /*
1206  * Error-check and convert a string of mount options from user space into
1207  * a data structure.  The whole mount string is processed; bad options are
1208  * skipped as they are encountered.  If there were no errors, return 1;
1209  * otherwise return 0 (zero).
1210  */
1211 static int nfs_parse_mount_options(char *raw,
1212                                    struct nfs_parsed_mount_data *mnt)
1213 {
1214         char *p, *string;
1215         int rc, sloppy = 0, invalid_option = 0;
1216         unsigned short protofamily = AF_UNSPEC;
1217         unsigned short mountfamily = AF_UNSPEC;
1218
1219         if (!raw) {
1220                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1221                 return 1;
1222         }
1223         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1224
1225         rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
1226         if (rc)
1227                 goto out_security_failure;
1228
1229         while ((p = strsep(&raw, ",")) != NULL) {
1230                 substring_t args[MAX_OPT_ARGS];
1231                 unsigned long option;
1232                 int token;
1233
1234                 if (!*p)
1235                         continue;
1236
1237                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1238
1239                 token = match_token(p, nfs_mount_option_tokens, args);
1240                 switch (token) {
1241
1242                 /*
1243                  * boolean options:  foo/nofoo
1244                  */
1245                 case Opt_soft:
1246                         mnt->flags |= NFS_MOUNT_SOFT;
1247                         mnt->flags &= ~NFS_MOUNT_SOFTERR;
1248                         break;
1249                 case Opt_softerr:
1250                         mnt->flags |= NFS_MOUNT_SOFTERR;
1251                         mnt->flags &= ~NFS_MOUNT_SOFT;
1252                         break;
1253                 case Opt_hard:
1254                         mnt->flags &= ~(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR);
1255                         break;
1256                 case Opt_posix:
1257                         mnt->flags |= NFS_MOUNT_POSIX;
1258                         break;
1259                 case Opt_noposix:
1260                         mnt->flags &= ~NFS_MOUNT_POSIX;
1261                         break;
1262                 case Opt_cto:
1263                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1264                         break;
1265                 case Opt_nocto:
1266                         mnt->flags |= NFS_MOUNT_NOCTO;
1267                         break;
1268                 case Opt_ac:
1269                         mnt->flags &= ~NFS_MOUNT_NOAC;
1270                         break;
1271                 case Opt_noac:
1272                         mnt->flags |= NFS_MOUNT_NOAC;
1273                         break;
1274                 case Opt_lock:
1275                         mnt->flags &= ~NFS_MOUNT_NONLM;
1276                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1277                                         NFS_MOUNT_LOCAL_FCNTL);
1278                         break;
1279                 case Opt_nolock:
1280                         mnt->flags |= NFS_MOUNT_NONLM;
1281                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1282                                        NFS_MOUNT_LOCAL_FCNTL);
1283                         break;
1284                 case Opt_udp:
1285                         mnt->flags &= ~NFS_MOUNT_TCP;
1286                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1287                         break;
1288                 case Opt_tcp:
1289                         mnt->flags |= NFS_MOUNT_TCP;
1290                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1291                         break;
1292                 case Opt_rdma:
1293                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1294                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1295                         xprt_load_transport(p);
1296                         break;
1297                 case Opt_acl:
1298                         mnt->flags &= ~NFS_MOUNT_NOACL;
1299                         break;
1300                 case Opt_noacl:
1301                         mnt->flags |= NFS_MOUNT_NOACL;
1302                         break;
1303                 case Opt_rdirplus:
1304                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1305                         break;
1306                 case Opt_nordirplus:
1307                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1308                         break;
1309                 case Opt_sharecache:
1310                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1311                         break;
1312                 case Opt_nosharecache:
1313                         mnt->flags |= NFS_MOUNT_UNSHARED;
1314                         break;
1315                 case Opt_resvport:
1316                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1317                         break;
1318                 case Opt_noresvport:
1319                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1320                         break;
1321                 case Opt_fscache:
1322                         mnt->options |= NFS_OPTION_FSCACHE;
1323                         kfree(mnt->fscache_uniq);
1324                         mnt->fscache_uniq = NULL;
1325                         break;
1326                 case Opt_nofscache:
1327                         mnt->options &= ~NFS_OPTION_FSCACHE;
1328                         kfree(mnt->fscache_uniq);
1329                         mnt->fscache_uniq = NULL;
1330                         break;
1331                 case Opt_migration:
1332                         mnt->options |= NFS_OPTION_MIGRATION;
1333                         break;
1334                 case Opt_nomigration:
1335                         mnt->options &= ~NFS_OPTION_MIGRATION;
1336                         break;
1337
1338                 /*
1339                  * options that take numeric values
1340                  */
1341                 case Opt_port:
1342                         if (nfs_get_option_ul(args, &option) ||
1343                             option > USHRT_MAX)
1344                                 goto out_invalid_value;
1345                         mnt->nfs_server.port = option;
1346                         break;
1347                 case Opt_rsize:
1348                         if (nfs_get_option_ul(args, &option))
1349                                 goto out_invalid_value;
1350                         mnt->rsize = option;
1351                         break;
1352                 case Opt_wsize:
1353                         if (nfs_get_option_ul(args, &option))
1354                                 goto out_invalid_value;
1355                         mnt->wsize = option;
1356                         break;
1357                 case Opt_bsize:
1358                         if (nfs_get_option_ul(args, &option))
1359                                 goto out_invalid_value;
1360                         mnt->bsize = option;
1361                         break;
1362                 case Opt_timeo:
1363                         if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
1364                                 goto out_invalid_value;
1365                         mnt->timeo = option;
1366                         break;
1367                 case Opt_retrans:
1368                         if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
1369                                 goto out_invalid_value;
1370                         mnt->retrans = option;
1371                         break;
1372                 case Opt_acregmin:
1373                         if (nfs_get_option_ul(args, &option))
1374                                 goto out_invalid_value;
1375                         mnt->acregmin = option;
1376                         break;
1377                 case Opt_acregmax:
1378                         if (nfs_get_option_ul(args, &option))
1379                                 goto out_invalid_value;
1380                         mnt->acregmax = option;
1381                         break;
1382                 case Opt_acdirmin:
1383                         if (nfs_get_option_ul(args, &option))
1384                                 goto out_invalid_value;
1385                         mnt->acdirmin = option;
1386                         break;
1387                 case Opt_acdirmax:
1388                         if (nfs_get_option_ul(args, &option))
1389                                 goto out_invalid_value;
1390                         mnt->acdirmax = option;
1391                         break;
1392                 case Opt_actimeo:
1393                         if (nfs_get_option_ul(args, &option))
1394                                 goto out_invalid_value;
1395                         mnt->acregmin = mnt->acregmax =
1396                         mnt->acdirmin = mnt->acdirmax = option;
1397                         break;
1398                 case Opt_namelen:
1399                         if (nfs_get_option_ul(args, &option))
1400                                 goto out_invalid_value;
1401                         mnt->namlen = option;
1402                         break;
1403                 case Opt_mountport:
1404                         if (nfs_get_option_ul(args, &option) ||
1405                             option > USHRT_MAX)
1406                                 goto out_invalid_value;
1407                         mnt->mount_server.port = option;
1408                         break;
1409                 case Opt_mountvers:
1410                         if (nfs_get_option_ul(args, &option) ||
1411                             option < NFS_MNT_VERSION ||
1412                             option > NFS_MNT3_VERSION)
1413                                 goto out_invalid_value;
1414                         mnt->mount_server.version = option;
1415                         break;
1416                 case Opt_minorversion:
1417                         if (nfs_get_option_ul(args, &option))
1418                                 goto out_invalid_value;
1419                         if (option > NFS4_MAX_MINOR_VERSION)
1420                                 goto out_invalid_value;
1421                         mnt->minorversion = option;
1422                         break;
1423
1424                 /*
1425                  * options that take text values
1426                  */
1427                 case Opt_nfsvers:
1428                         string = match_strdup(args);
1429                         if (string == NULL)
1430                                 goto out_nomem;
1431                         rc = nfs_parse_version_string(string, mnt, args);
1432                         kfree(string);
1433                         if (!rc)
1434                                 goto out_invalid_value;
1435                         break;
1436                 case Opt_sec:
1437                         string = match_strdup(args);
1438                         if (string == NULL)
1439                                 goto out_nomem;
1440                         rc = nfs_parse_security_flavors(string, mnt);
1441                         kfree(string);
1442                         if (!rc) {
1443                                 dfprintk(MOUNT, "NFS:   unrecognized "
1444                                                 "security flavor\n");
1445                                 return 0;
1446                         }
1447                         break;
1448                 case Opt_proto:
1449                         string = match_strdup(args);
1450                         if (string == NULL)
1451                                 goto out_nomem;
1452                         token = match_token(string,
1453                                             nfs_xprt_protocol_tokens, args);
1454
1455                         protofamily = AF_INET;
1456                         switch (token) {
1457                         case Opt_xprt_udp6:
1458                                 protofamily = AF_INET6;
1459                                 /* fall through */
1460                         case Opt_xprt_udp:
1461                                 mnt->flags &= ~NFS_MOUNT_TCP;
1462                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1463                                 break;
1464                         case Opt_xprt_tcp6:
1465                                 protofamily = AF_INET6;
1466                                 /* fall through */
1467                         case Opt_xprt_tcp:
1468                                 mnt->flags |= NFS_MOUNT_TCP;
1469                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1470                                 break;
1471                         case Opt_xprt_rdma6:
1472                                 protofamily = AF_INET6;
1473                                 /* fall through */
1474                         case Opt_xprt_rdma:
1475                                 /* vector side protocols to TCP */
1476                                 mnt->flags |= NFS_MOUNT_TCP;
1477                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1478                                 xprt_load_transport(string);
1479                                 break;
1480                         default:
1481                                 dfprintk(MOUNT, "NFS:   unrecognized "
1482                                                 "transport protocol\n");
1483                                 kfree(string);
1484                                 return 0;
1485                         }
1486                         kfree(string);
1487                         break;
1488                 case Opt_mountproto:
1489                         string = match_strdup(args);
1490                         if (string == NULL)
1491                                 goto out_nomem;
1492                         token = match_token(string,
1493                                             nfs_xprt_protocol_tokens, args);
1494                         kfree(string);
1495
1496                         mountfamily = AF_INET;
1497                         switch (token) {
1498                         case Opt_xprt_udp6:
1499                                 mountfamily = AF_INET6;
1500                                 /* fall through */
1501                         case Opt_xprt_udp:
1502                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1503                                 break;
1504                         case Opt_xprt_tcp6:
1505                                 mountfamily = AF_INET6;
1506                                 /* fall through */
1507                         case Opt_xprt_tcp:
1508                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1509                                 break;
1510                         case Opt_xprt_rdma: /* not used for side protocols */
1511                         default:
1512                                 dfprintk(MOUNT, "NFS:   unrecognized "
1513                                                 "transport protocol\n");
1514                                 return 0;
1515                         }
1516                         break;
1517                 case Opt_addr:
1518                         string = match_strdup(args);
1519                         if (string == NULL)
1520                                 goto out_nomem;
1521                         mnt->nfs_server.addrlen =
1522                                 rpc_pton(mnt->net, string, strlen(string),
1523                                         (struct sockaddr *)
1524                                         &mnt->nfs_server.address,
1525                                         sizeof(mnt->nfs_server.address));
1526                         kfree(string);
1527                         if (mnt->nfs_server.addrlen == 0)
1528                                 goto out_invalid_address;
1529                         break;
1530                 case Opt_clientaddr:
1531                         if (nfs_get_option_str(args, &mnt->client_address))
1532                                 goto out_nomem;
1533                         break;
1534                 case Opt_mounthost:
1535                         if (nfs_get_option_str(args,
1536                                                &mnt->mount_server.hostname))
1537                                 goto out_nomem;
1538                         break;
1539                 case Opt_mountaddr:
1540                         string = match_strdup(args);
1541                         if (string == NULL)
1542                                 goto out_nomem;
1543                         mnt->mount_server.addrlen =
1544                                 rpc_pton(mnt->net, string, strlen(string),
1545                                         (struct sockaddr *)
1546                                         &mnt->mount_server.address,
1547                                         sizeof(mnt->mount_server.address));
1548                         kfree(string);
1549                         if (mnt->mount_server.addrlen == 0)
1550                                 goto out_invalid_address;
1551                         break;
1552                 case Opt_lookupcache:
1553                         string = match_strdup(args);
1554                         if (string == NULL)
1555                                 goto out_nomem;
1556                         token = match_token(string,
1557                                         nfs_lookupcache_tokens, args);
1558                         kfree(string);
1559                         switch (token) {
1560                                 case Opt_lookupcache_all:
1561                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1562                                         break;
1563                                 case Opt_lookupcache_positive:
1564                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1565                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1566                                         break;
1567                                 case Opt_lookupcache_none:
1568                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1569                                         break;
1570                                 default:
1571                                         dfprintk(MOUNT, "NFS:   invalid "
1572                                                         "lookupcache argument\n");
1573                                         return 0;
1574                         };
1575                         break;
1576                 case Opt_fscache_uniq:
1577                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1578                                 goto out_nomem;
1579                         mnt->options |= NFS_OPTION_FSCACHE;
1580                         break;
1581                 case Opt_local_lock:
1582                         string = match_strdup(args);
1583                         if (string == NULL)
1584                                 goto out_nomem;
1585                         token = match_token(string, nfs_local_lock_tokens,
1586                                         args);
1587                         kfree(string);
1588                         switch (token) {
1589                         case Opt_local_lock_all:
1590                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1591                                                NFS_MOUNT_LOCAL_FCNTL);
1592                                 break;
1593                         case Opt_local_lock_flock:
1594                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1595                                 break;
1596                         case Opt_local_lock_posix:
1597                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1598                                 break;
1599                         case Opt_local_lock_none:
1600                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1601                                                 NFS_MOUNT_LOCAL_FCNTL);
1602                                 break;
1603                         default:
1604                                 dfprintk(MOUNT, "NFS:   invalid "
1605                                                 "local_lock argument\n");
1606                                 return 0;
1607                         };
1608                         break;
1609
1610                 /*
1611                  * Special options
1612                  */
1613                 case Opt_sloppy:
1614                         sloppy = 1;
1615                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1616                         break;
1617                 case Opt_userspace:
1618                 case Opt_deprecated:
1619                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1620                                         "'%s'\n", p);
1621                         break;
1622
1623                 default:
1624                         invalid_option = 1;
1625                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1626                                         "'%s'\n", p);
1627                 }
1628         }
1629
1630         if (!sloppy && invalid_option)
1631                 return 0;
1632
1633         if (mnt->minorversion && mnt->version != 4)
1634                 goto out_minorversion_mismatch;
1635
1636         if (mnt->options & NFS_OPTION_MIGRATION &&
1637             (mnt->version != 4 || mnt->minorversion != 0))
1638                 goto out_migration_misuse;
1639
1640         /*
1641          * verify that any proto=/mountproto= options match the address
1642          * families in the addr=/mountaddr= options.
1643          */
1644         if (protofamily != AF_UNSPEC &&
1645             protofamily != mnt->nfs_server.address.ss_family)
1646                 goto out_proto_mismatch;
1647
1648         if (mountfamily != AF_UNSPEC) {
1649                 if (mnt->mount_server.addrlen) {
1650                         if (mountfamily != mnt->mount_server.address.ss_family)
1651                                 goto out_mountproto_mismatch;
1652                 } else {
1653                         if (mountfamily != mnt->nfs_server.address.ss_family)
1654                                 goto out_mountproto_mismatch;
1655                 }
1656         }
1657
1658         return 1;
1659
1660 out_mountproto_mismatch:
1661         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1662                          "option\n");
1663         return 0;
1664 out_proto_mismatch:
1665         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1666         return 0;
1667 out_invalid_address:
1668         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1669         return 0;
1670 out_invalid_value:
1671         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1672         return 0;
1673 out_minorversion_mismatch:
1674         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1675                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1676         return 0;
1677 out_migration_misuse:
1678         printk(KERN_INFO
1679                 "NFS: 'migration' not supported for this NFS version\n");
1680         return 0;
1681 out_nomem:
1682         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1683         return 0;
1684 out_security_failure:
1685         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1686         return 0;
1687 }
1688
1689 /*
1690  * Ensure that a specified authtype in args->auth_info is supported by
1691  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1692  * -EACCES if not.
1693  */
1694 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1695                         rpc_authflavor_t *server_authlist, unsigned int count)
1696 {
1697         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1698         bool found_auth_null = false;
1699         unsigned int i;
1700
1701         /*
1702          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1703          * must be in the list returned by the server.
1704          *
1705          * AUTH_NULL has a special meaning when it's in the server list - it
1706          * means that the server will ignore the rpc creds, so any flavor
1707          * can be used but still use the sec= that was specified.
1708          *
1709          * Note also that the MNT procedure in MNTv1 does not return a list
1710          * of supported security flavors. In this case, nfs_mount() fabricates
1711          * a security flavor list containing just AUTH_NULL.
1712          */
1713         for (i = 0; i < count; i++) {
1714                 flavor = server_authlist[i];
1715
1716                 if (nfs_auth_info_match(&args->auth_info, flavor))
1717                         goto out;
1718
1719                 if (flavor == RPC_AUTH_NULL)
1720                         found_auth_null = true;
1721         }
1722
1723         if (found_auth_null) {
1724                 flavor = args->auth_info.flavors[0];
1725                 goto out;
1726         }
1727
1728         dfprintk(MOUNT,
1729                  "NFS: specified auth flavors not supported by server\n");
1730         return -EACCES;
1731
1732 out:
1733         args->selected_flavor = flavor;
1734         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1735         return 0;
1736 }
1737
1738 /*
1739  * Use the remote server's MOUNT service to request the NFS file handle
1740  * corresponding to the provided path.
1741  */
1742 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1743                              struct nfs_fh *root_fh,
1744                              rpc_authflavor_t *server_authlist,
1745                              unsigned int *server_authlist_len)
1746 {
1747         struct nfs_mount_request request = {
1748                 .sap            = (struct sockaddr *)
1749                                                 &args->mount_server.address,
1750                 .dirpath        = args->nfs_server.export_path,
1751                 .protocol       = args->mount_server.protocol,
1752                 .fh             = root_fh,
1753                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1754                 .auth_flav_len  = server_authlist_len,
1755                 .auth_flavs     = server_authlist,
1756                 .net            = args->net,
1757         };
1758         int status;
1759
1760         if (args->mount_server.version == 0) {
1761                 switch (args->version) {
1762                         default:
1763                                 args->mount_server.version = NFS_MNT3_VERSION;
1764                                 break;
1765                         case 2:
1766                                 args->mount_server.version = NFS_MNT_VERSION;
1767                 }
1768         }
1769         request.version = args->mount_server.version;
1770
1771         if (args->mount_server.hostname)
1772                 request.hostname = args->mount_server.hostname;
1773         else
1774                 request.hostname = args->nfs_server.hostname;
1775
1776         /*
1777          * Construct the mount server's address.
1778          */
1779         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1780                 memcpy(request.sap, &args->nfs_server.address,
1781                        args->nfs_server.addrlen);
1782                 args->mount_server.addrlen = args->nfs_server.addrlen;
1783         }
1784         request.salen = args->mount_server.addrlen;
1785         nfs_set_port(request.sap, &args->mount_server.port, 0);
1786
1787         /*
1788          * Now ask the mount server to map our export path
1789          * to a file handle.
1790          */
1791         status = nfs_mount(&request);
1792         if (status != 0) {
1793                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1794                                 request.hostname, status);
1795                 return status;
1796         }
1797
1798         return 0;
1799 }
1800
1801 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1802                                         struct nfs_subversion *nfs_mod)
1803 {
1804         int status;
1805         unsigned int i;
1806         bool tried_auth_unix = false;
1807         bool auth_null_in_list = false;
1808         struct nfs_server *server = ERR_PTR(-EACCES);
1809         struct nfs_parsed_mount_data *args = mount_info->parsed;
1810         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1811         unsigned int authlist_len = ARRAY_SIZE(authlist);
1812
1813         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1814                                         &authlist_len);
1815         if (status)
1816                 return ERR_PTR(status);
1817
1818         /*
1819          * Was a sec= authflavor specified in the options? First, verify
1820          * whether the server supports it, and then just try to use it if so.
1821          */
1822         if (args->auth_info.flavor_len > 0) {
1823                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1824                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1825                          args->selected_flavor);
1826                 if (status)
1827                         return ERR_PTR(status);
1828                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1829         }
1830
1831         /*
1832          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1833          * SHOULD prefer the flavor listed first. However, some servers list
1834          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1835          */
1836         for (i = 0; i < authlist_len; ++i) {
1837                 rpc_authflavor_t flavor;
1838                 struct rpcsec_gss_info info;
1839
1840                 flavor = authlist[i];
1841                 switch (flavor) {
1842                 case RPC_AUTH_UNIX:
1843                         tried_auth_unix = true;
1844                         break;
1845                 case RPC_AUTH_NULL:
1846                         auth_null_in_list = true;
1847                         continue;
1848                 default:
1849                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1850                                 continue;
1851                         /* Fallthrough */
1852                 }
1853                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1854                 args->selected_flavor = flavor;
1855                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1856                 if (!IS_ERR(server))
1857                         return server;
1858         }
1859
1860         /*
1861          * Nothing we tried so far worked. At this point, give up if we've
1862          * already tried AUTH_UNIX or if the server's list doesn't contain
1863          * AUTH_NULL
1864          */
1865         if (tried_auth_unix || !auth_null_in_list)
1866                 return server;
1867
1868         /* Last chance! Try AUTH_UNIX */
1869         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1870         args->selected_flavor = RPC_AUTH_UNIX;
1871         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1872 }
1873
1874 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1875                              struct nfs_mount_info *mount_info,
1876                              struct nfs_subversion *nfs_mod)
1877 {
1878         struct nfs_server *server;
1879
1880         if (mount_info->parsed->need_mount)
1881                 server = nfs_try_mount_request(mount_info, nfs_mod);
1882         else
1883                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1884
1885         if (IS_ERR(server))
1886                 return ERR_CAST(server);
1887
1888         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1889 }
1890 EXPORT_SYMBOL_GPL(nfs_try_mount);
1891
1892 /*
1893  * Split "dev_name" into "hostname:export_path".
1894  *
1895  * The leftmost colon demarks the split between the server's hostname
1896  * and the export path.  If the hostname starts with a left square
1897  * bracket, then it may contain colons.
1898  *
1899  * Note: caller frees hostname and export path, even on error.
1900  */
1901 static int nfs_parse_devname(const char *dev_name,
1902                              char **hostname, size_t maxnamlen,
1903                              char **export_path, size_t maxpathlen)
1904 {
1905         size_t len;
1906         char *end;
1907
1908         if (unlikely(!dev_name || !*dev_name)) {
1909                 dfprintk(MOUNT, "NFS: device name not specified\n");
1910                 return -EINVAL;
1911         }
1912
1913         /* Is the host name protected with square brakcets? */
1914         if (*dev_name == '[') {
1915                 end = strchr(++dev_name, ']');
1916                 if (end == NULL || end[1] != ':')
1917                         goto out_bad_devname;
1918
1919                 len = end - dev_name;
1920                 end++;
1921         } else {
1922                 char *comma;
1923
1924                 end = strchr(dev_name, ':');
1925                 if (end == NULL)
1926                         goto out_bad_devname;
1927                 len = end - dev_name;
1928
1929                 /* kill possible hostname list: not supported */
1930                 comma = strchr(dev_name, ',');
1931                 if (comma != NULL && comma < end)
1932                         len = comma - dev_name;
1933         }
1934
1935         if (len > maxnamlen)
1936                 goto out_hostname;
1937
1938         /* N.B. caller will free nfs_server.hostname in all cases */
1939         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1940         if (*hostname == NULL)
1941                 goto out_nomem;
1942         len = strlen(++end);
1943         if (len > maxpathlen)
1944                 goto out_path;
1945         *export_path = kstrndup(end, len, GFP_KERNEL);
1946         if (!*export_path)
1947                 goto out_nomem;
1948
1949         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1950         return 0;
1951
1952 out_bad_devname:
1953         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1954         return -EINVAL;
1955
1956 out_nomem:
1957         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1958         return -ENOMEM;
1959
1960 out_hostname:
1961         dfprintk(MOUNT, "NFS: server hostname too long\n");
1962         return -ENAMETOOLONG;
1963
1964 out_path:
1965         dfprintk(MOUNT, "NFS: export pathname too long\n");
1966         return -ENAMETOOLONG;
1967 }
1968
1969 /*
1970  * Validate the NFS2/NFS3 mount data
1971  * - fills in the mount root filehandle
1972  *
1973  * For option strings, user space handles the following behaviors:
1974  *
1975  * + DNS: mapping server host name to IP address ("addr=" option)
1976  *
1977  * + failure mode: how to behave if a mount request can't be handled
1978  *   immediately ("fg/bg" option)
1979  *
1980  * + retry: how often to retry a mount request ("retry=" option)
1981  *
1982  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1983  *   mountproto=tcp after mountproto=udp, and so on
1984  */
1985 static int nfs23_validate_mount_data(void *options,
1986                                      struct nfs_parsed_mount_data *args,
1987                                      struct nfs_fh *mntfh,
1988                                      const char *dev_name)
1989 {
1990         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1991         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1992         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1993
1994         if (data == NULL)
1995                 goto out_no_data;
1996
1997         args->version = NFS_DEFAULT_VERSION;
1998         switch (data->version) {
1999         case 1:
2000                 data->namlen = 0; /* fall through */
2001         case 2:
2002                 data->bsize = 0; /* fall through */
2003         case 3:
2004                 if (data->flags & NFS_MOUNT_VER3)
2005                         goto out_no_v3;
2006                 data->root.size = NFS2_FHSIZE;
2007                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
2008                 /* Turn off security negotiation */
2009                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
2010                 /* fall through */
2011         case 4:
2012                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2013                         goto out_no_sec;
2014                 /* fall through */
2015         case 5:
2016                 memset(data->context, 0, sizeof(data->context));
2017                 /* fall through */
2018         case 6:
2019                 if (data->flags & NFS_MOUNT_VER3) {
2020                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2021                                 goto out_invalid_fh;
2022                         mntfh->size = data->root.size;
2023                         args->version = 3;
2024                 } else {
2025                         mntfh->size = NFS2_FHSIZE;
2026                         args->version = 2;
2027                 }
2028
2029
2030                 memcpy(mntfh->data, data->root.data, mntfh->size);
2031                 if (mntfh->size < sizeof(mntfh->data))
2032                         memset(mntfh->data + mntfh->size, 0,
2033                                sizeof(mntfh->data) - mntfh->size);
2034
2035                 /*
2036                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
2037                  * can deal with.
2038                  */
2039                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2040                 args->flags             |= extra_flags;
2041                 args->rsize             = data->rsize;
2042                 args->wsize             = data->wsize;
2043                 args->timeo             = data->timeo;
2044                 args->retrans           = data->retrans;
2045                 args->acregmin          = data->acregmin;
2046                 args->acregmax          = data->acregmax;
2047                 args->acdirmin          = data->acdirmin;
2048                 args->acdirmax          = data->acdirmax;
2049                 args->need_mount        = false;
2050
2051                 memcpy(sap, &data->addr, sizeof(data->addr));
2052                 args->nfs_server.addrlen = sizeof(data->addr);
2053                 args->nfs_server.port = ntohs(data->addr.sin_port);
2054                 if (sap->sa_family != AF_INET ||
2055                     !nfs_verify_server_address(sap))
2056                         goto out_no_address;
2057
2058                 if (!(data->flags & NFS_MOUNT_TCP))
2059                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2060                 /* N.B. caller will free nfs_server.hostname in all cases */
2061                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2062                 args->namlen            = data->namlen;
2063                 args->bsize             = data->bsize;
2064
2065                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2066                         args->selected_flavor = data->pseudoflavor;
2067                 else
2068                         args->selected_flavor = RPC_AUTH_UNIX;
2069                 if (!args->nfs_server.hostname)
2070                         goto out_nomem;
2071
2072                 if (!(data->flags & NFS_MOUNT_NONLM))
2073                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2074                                          NFS_MOUNT_LOCAL_FCNTL);
2075                 else
2076                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2077                                         NFS_MOUNT_LOCAL_FCNTL);
2078                 /*
2079                  * The legacy version 6 binary mount data from userspace has a
2080                  * field used only to transport selinux information into the
2081                  * the kernel.  To continue to support that functionality we
2082                  * have a touch of selinux knowledge here in the NFS code. The
2083                  * userspace code converted context=blah to just blah so we are
2084                  * converting back to the full string selinux understands.
2085                  */
2086                 if (data->context[0]){
2087 #ifdef CONFIG_SECURITY_SELINUX
2088                         int rc;
2089                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2090                         rc = security_add_mnt_opt("context", data->context,
2091                                         strlen(data->context), &args->lsm_opts);
2092                         if (rc)
2093                                 return rc;
2094 #else
2095                         return -EINVAL;
2096 #endif
2097                 }
2098
2099                 break;
2100         default:
2101                 return NFS_TEXT_DATA;
2102         }
2103
2104         return 0;
2105
2106 out_no_data:
2107         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2108         return -EINVAL;
2109
2110 out_no_v3:
2111         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2112                  data->version);
2113         return -EINVAL;
2114
2115 out_no_sec:
2116         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2117         return -EINVAL;
2118
2119 out_nomem:
2120         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2121         return -ENOMEM;
2122
2123 out_no_address:
2124         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2125         return -EINVAL;
2126
2127 out_invalid_fh:
2128         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2129         return -EINVAL;
2130 }
2131
2132 #if IS_ENABLED(CONFIG_NFS_V4)
2133 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2134                                    void *options,
2135                                    struct nfs_parsed_mount_data *args,
2136                                    struct nfs_fh *mntfh,
2137                                    const char *dev_name)
2138 {
2139         if (fs_type == &nfs_fs_type)
2140                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2141         return nfs4_validate_mount_data(options, args, dev_name);
2142 }
2143 #else
2144 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2145                                    void *options,
2146                                    struct nfs_parsed_mount_data *args,
2147                                    struct nfs_fh *mntfh,
2148                                    const char *dev_name)
2149 {
2150         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2151 }
2152 #endif
2153
2154 static int nfs_validate_text_mount_data(void *options,
2155                                         struct nfs_parsed_mount_data *args,
2156                                         const char *dev_name)
2157 {
2158         int port = 0;
2159         int max_namelen = PAGE_SIZE;
2160         int max_pathlen = NFS_MAXPATHLEN;
2161         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2162
2163         if (nfs_parse_mount_options((char *)options, args) == 0)
2164                 return -EINVAL;
2165
2166         if (!nfs_verify_server_address(sap))
2167                 goto out_no_address;
2168
2169         if (args->version == 4) {
2170 #if IS_ENABLED(CONFIG_NFS_V4)
2171                 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2172                         port = NFS_RDMA_PORT;
2173                 else
2174                         port = NFS_PORT;
2175                 max_namelen = NFS4_MAXNAMLEN;
2176                 max_pathlen = NFS4_MAXPATHLEN;
2177                 nfs_validate_transport_protocol(args);
2178                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2179                         goto out_invalid_transport_udp;
2180                 nfs4_validate_mount_flags(args);
2181 #else
2182                 goto out_v4_not_compiled;
2183 #endif /* CONFIG_NFS_V4 */
2184         } else {
2185                 nfs_set_mount_transport_protocol(args);
2186                 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2187                         port = NFS_RDMA_PORT;
2188         }
2189
2190         nfs_set_port(sap, &args->nfs_server.port, port);
2191
2192         return nfs_parse_devname(dev_name,
2193                                    &args->nfs_server.hostname,
2194                                    max_namelen,
2195                                    &args->nfs_server.export_path,
2196                                    max_pathlen);
2197
2198 #if !IS_ENABLED(CONFIG_NFS_V4)
2199 out_v4_not_compiled:
2200         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2201         return -EPROTONOSUPPORT;
2202 #else
2203 out_invalid_transport_udp:
2204         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2205         return -EINVAL;
2206 #endif /* !CONFIG_NFS_V4 */
2207
2208 out_no_address:
2209         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2210         return -EINVAL;
2211 }
2212
2213 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2214                 | NFS_MOUNT_SECURE \
2215                 | NFS_MOUNT_TCP \
2216                 | NFS_MOUNT_VER3 \
2217                 | NFS_MOUNT_KERBEROS \
2218                 | NFS_MOUNT_NONLM \
2219                 | NFS_MOUNT_BROKEN_SUID \
2220                 | NFS_MOUNT_STRICTLOCK \
2221                 | NFS_MOUNT_LEGACY_INTERFACE)
2222
2223 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2224                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2225
2226 static int
2227 nfs_compare_remount_data(struct nfs_server *nfss,
2228                          struct nfs_parsed_mount_data *data)
2229 {
2230         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2231             data->rsize != nfss->rsize ||
2232             data->wsize != nfss->wsize ||
2233             data->version != nfss->nfs_client->rpc_ops->version ||
2234             data->minorversion != nfss->nfs_client->cl_minorversion ||
2235             data->retrans != nfss->client->cl_timeout->to_retries ||
2236             !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2237             data->acregmin != nfss->acregmin / HZ ||
2238             data->acregmax != nfss->acregmax / HZ ||
2239             data->acdirmin != nfss->acdirmin / HZ ||
2240             data->acdirmax != nfss->acdirmax / HZ ||
2241             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2242             data->nfs_server.port != nfss->port ||
2243             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2244             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2245                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2246                 return -EINVAL;
2247
2248         return 0;
2249 }
2250
2251 int
2252 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2253 {
2254         int error;
2255         struct nfs_server *nfss = sb->s_fs_info;
2256         struct nfs_parsed_mount_data *data;
2257         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2258         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2259         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2260
2261         sync_filesystem(sb);
2262
2263         /*
2264          * Userspace mount programs that send binary options generally send
2265          * them populated with default values. We have no way to know which
2266          * ones were explicitly specified. Fall back to legacy behavior and
2267          * just return success.
2268          */
2269         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2270             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2271                                            options->version <= 6))))
2272                 return 0;
2273
2274         data = nfs_alloc_parsed_mount_data();
2275         if (data == NULL)
2276                 return -ENOMEM;
2277
2278         /* fill out struct with values from existing mount */
2279         data->flags = nfss->flags;
2280         data->rsize = nfss->rsize;
2281         data->wsize = nfss->wsize;
2282         data->retrans = nfss->client->cl_timeout->to_retries;
2283         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2284         data->acregmin = nfss->acregmin / HZ;
2285         data->acregmax = nfss->acregmax / HZ;
2286         data->acdirmin = nfss->acdirmin / HZ;
2287         data->acdirmax = nfss->acdirmax / HZ;
2288         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2289         data->nfs_server.port = nfss->port;
2290         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2291         data->version = nfsvers;
2292         data->minorversion = nfss->nfs_client->cl_minorversion;
2293         data->net = current->nsproxy->net_ns;
2294         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2295                 data->nfs_server.addrlen);
2296
2297         /* overwrite those values with any that were specified */
2298         error = -EINVAL;
2299         if (!nfs_parse_mount_options((char *)options, data))
2300                 goto out;
2301
2302         /*
2303          * noac is a special case. It implies -o sync, but that's not
2304          * necessarily reflected in the mtab options. do_remount_sb
2305          * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
2306          * remount options, so we have to explicitly reset it.
2307          */
2308         if (data->flags & NFS_MOUNT_NOAC)
2309                 *flags |= SB_SYNCHRONOUS;
2310
2311         /* compare new mount options with old ones */
2312         error = nfs_compare_remount_data(nfss, data);
2313         if (!error)
2314                 error = security_sb_remount(sb, data->lsm_opts);
2315 out:
2316         nfs_free_parsed_mount_data(data);
2317         return error;
2318 }
2319 EXPORT_SYMBOL_GPL(nfs_remount);
2320
2321 /*
2322  * Initialise the common bits of the superblock
2323  */
2324 static void nfs_initialise_sb(struct super_block *sb)
2325 {
2326         struct nfs_server *server = NFS_SB(sb);
2327
2328         sb->s_magic = NFS_SUPER_MAGIC;
2329
2330         /* We probably want something more informative here */
2331         snprintf(sb->s_id, sizeof(sb->s_id),
2332                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2333
2334         if (sb->s_blocksize == 0)
2335                 sb->s_blocksize = nfs_block_bits(server->wsize,
2336                                                  &sb->s_blocksize_bits);
2337
2338         nfs_super_set_maxbytes(sb, server->maxfilesize);
2339 }
2340
2341 /*
2342  * Finish setting up an NFS2/3 superblock
2343  */
2344 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2345 {
2346         struct nfs_parsed_mount_data *data = mount_info->parsed;
2347         struct nfs_server *server = NFS_SB(sb);
2348
2349         sb->s_blocksize_bits = 0;
2350         sb->s_blocksize = 0;
2351         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2352         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2353         if (data && data->bsize)
2354                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2355
2356         if (server->nfs_client->rpc_ops->version != 2) {
2357                 /* The VFS shouldn't apply the umask to mode bits. We will do
2358                  * so ourselves when necessary.
2359                  */
2360                 sb->s_flags |= SB_POSIXACL;
2361                 sb->s_time_gran = 1;
2362                 sb->s_export_op = &nfs_export_ops;
2363         }
2364
2365         nfs_initialise_sb(sb);
2366 }
2367 EXPORT_SYMBOL_GPL(nfs_fill_super);
2368
2369 /*
2370  * Finish setting up a cloned NFS2/3/4 superblock
2371  */
2372 static void nfs_clone_super(struct super_block *sb,
2373                             struct nfs_mount_info *mount_info)
2374 {
2375         const struct super_block *old_sb = mount_info->cloned->sb;
2376         struct nfs_server *server = NFS_SB(sb);
2377
2378         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2379         sb->s_blocksize = old_sb->s_blocksize;
2380         sb->s_maxbytes = old_sb->s_maxbytes;
2381         sb->s_xattr = old_sb->s_xattr;
2382         sb->s_op = old_sb->s_op;
2383         sb->s_time_gran = 1;
2384         sb->s_export_op = old_sb->s_export_op;
2385
2386         if (server->nfs_client->rpc_ops->version != 2) {
2387                 /* The VFS shouldn't apply the umask to mode bits. We will do
2388                  * so ourselves when necessary.
2389                  */
2390                 sb->s_flags |= SB_POSIXACL;
2391         }
2392
2393         nfs_initialise_sb(sb);
2394 }
2395
2396 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2397 {
2398         const struct nfs_server *a = s->s_fs_info;
2399         const struct rpc_clnt *clnt_a = a->client;
2400         const struct rpc_clnt *clnt_b = b->client;
2401
2402         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2403                 goto Ebusy;
2404         if (a->nfs_client != b->nfs_client)
2405                 goto Ebusy;
2406         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2407                 goto Ebusy;
2408         if (a->wsize != b->wsize)
2409                 goto Ebusy;
2410         if (a->rsize != b->rsize)
2411                 goto Ebusy;
2412         if (a->acregmin != b->acregmin)
2413                 goto Ebusy;
2414         if (a->acregmax != b->acregmax)
2415                 goto Ebusy;
2416         if (a->acdirmin != b->acdirmin)
2417                 goto Ebusy;
2418         if (a->acdirmax != b->acdirmax)
2419                 goto Ebusy;
2420         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2421                 goto Ebusy;
2422         return 1;
2423 Ebusy:
2424         return 0;
2425 }
2426
2427 struct nfs_sb_mountdata {
2428         struct nfs_server *server;
2429         int mntflags;
2430 };
2431
2432 static int nfs_set_super(struct super_block *s, void *data)
2433 {
2434         struct nfs_sb_mountdata *sb_mntdata = data;
2435         struct nfs_server *server = sb_mntdata->server;
2436         int ret;
2437
2438         s->s_flags = sb_mntdata->mntflags;
2439         s->s_fs_info = server;
2440         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2441         ret = set_anon_super(s, server);
2442         if (ret == 0)
2443                 server->s_dev = s->s_dev;
2444         return ret;
2445 }
2446
2447 static int nfs_compare_super_address(struct nfs_server *server1,
2448                                      struct nfs_server *server2)
2449 {
2450         struct sockaddr *sap1, *sap2;
2451         struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2452         struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2453
2454         if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2455                 return 0;
2456
2457         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2458         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2459
2460         if (sap1->sa_family != sap2->sa_family)
2461                 return 0;
2462
2463         switch (sap1->sa_family) {
2464         case AF_INET: {
2465                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2466                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2467                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2468                         return 0;
2469                 if (sin1->sin_port != sin2->sin_port)
2470                         return 0;
2471                 break;
2472         }
2473         case AF_INET6: {
2474                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2475                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2476                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2477                         return 0;
2478                 if (sin1->sin6_port != sin2->sin6_port)
2479                         return 0;
2480                 break;
2481         }
2482         default:
2483                 return 0;
2484         }
2485
2486         return 1;
2487 }
2488
2489 static int nfs_compare_userns(const struct nfs_server *old,
2490                 const struct nfs_server *new)
2491 {
2492         const struct user_namespace *oldns = &init_user_ns;
2493         const struct user_namespace *newns = &init_user_ns;
2494
2495         if (old->client && old->client->cl_cred)
2496                 oldns = old->client->cl_cred->user_ns;
2497         if (new->client && new->client->cl_cred)
2498                 newns = new->client->cl_cred->user_ns;
2499         if (oldns != newns)
2500                 return 0;
2501         return 1;
2502 }
2503
2504 static int nfs_compare_super(struct super_block *sb, void *data)
2505 {
2506         struct nfs_sb_mountdata *sb_mntdata = data;
2507         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2508         int mntflags = sb_mntdata->mntflags;
2509
2510         if (!nfs_compare_super_address(old, server))
2511                 return 0;
2512         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2513         if (old->flags & NFS_MOUNT_UNSHARED)
2514                 return 0;
2515         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2516                 return 0;
2517         if (!nfs_compare_userns(old, server))
2518                 return 0;
2519         return nfs_compare_mount_options(sb, server, mntflags);
2520 }
2521
2522 #ifdef CONFIG_NFS_FSCACHE
2523 static void nfs_get_cache_cookie(struct super_block *sb,
2524                                  struct nfs_parsed_mount_data *parsed,
2525                                  struct nfs_clone_mount *cloned)
2526 {
2527         struct nfs_server *nfss = NFS_SB(sb);
2528         char *uniq = NULL;
2529         int ulen = 0;
2530
2531         nfss->fscache_key = NULL;
2532         nfss->fscache = NULL;
2533
2534         if (parsed) {
2535                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2536                         return;
2537                 if (parsed->fscache_uniq) {
2538                         uniq = parsed->fscache_uniq;
2539                         ulen = strlen(parsed->fscache_uniq);
2540                 }
2541         } else if (cloned) {
2542                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2543                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2544                         return;
2545                 if (mnt_s->fscache_key) {
2546                         uniq = mnt_s->fscache_key->key.uniquifier;
2547                         ulen = mnt_s->fscache_key->key.uniq_len;
2548                 };
2549         } else
2550                 return;
2551
2552         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2553 }
2554 #else
2555 static void nfs_get_cache_cookie(struct super_block *sb,
2556                                  struct nfs_parsed_mount_data *parsed,
2557                                  struct nfs_clone_mount *cloned)
2558 {
2559 }
2560 #endif
2561
2562 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2563                         struct nfs_mount_info *mount_info)
2564 {
2565         int error;
2566         unsigned long kflags = 0, kflags_out = 0;
2567         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2568                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2569
2570         error = security_sb_set_mnt_opts(s, mount_info->parsed->lsm_opts,
2571                                                 kflags, &kflags_out);
2572         if (error)
2573                 goto err;
2574
2575         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2576                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2577                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2578 err:
2579         return error;
2580 }
2581 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2582
2583 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2584                           struct nfs_mount_info *mount_info)
2585 {
2586         int error;
2587         unsigned long kflags = 0, kflags_out = 0;
2588
2589         /* clone any lsm security options from the parent to the new sb */
2590         if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2591                 return -ESTALE;
2592
2593         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2594                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2595
2596         error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
2597                         &kflags_out);
2598         if (error)
2599                 return error;
2600
2601         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2602                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2603                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2604         return 0;
2605 }
2606 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2607
2608 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2609                                    int flags, const char *dev_name,
2610                                    struct nfs_mount_info *mount_info,
2611                                    struct nfs_subversion *nfs_mod)
2612 {
2613         struct super_block *s;
2614         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2615         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2616         struct nfs_sb_mountdata sb_mntdata = {
2617                 .mntflags = flags,
2618                 .server = server,
2619         };
2620         int error;
2621
2622         if (server->flags & NFS_MOUNT_UNSHARED)
2623                 compare_super = NULL;
2624
2625         /* -o noac implies -o sync */
2626         if (server->flags & NFS_MOUNT_NOAC)
2627                 sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2628
2629         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2630                 if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
2631                         sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2632
2633         /* Get a superblock - note that we may end up sharing one that already exists */
2634         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2635         if (IS_ERR(s)) {
2636                 mntroot = ERR_CAST(s);
2637                 goto out_err_nosb;
2638         }
2639
2640         if (s->s_fs_info != server) {
2641                 nfs_free_server(server);
2642                 server = NULL;
2643         } else {
2644                 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
2645                                              MINOR(server->s_dev));
2646                 if (error) {
2647                         mntroot = ERR_PTR(error);
2648                         goto error_splat_super;
2649                 }
2650                 s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
2651                 server->super = s;
2652         }
2653
2654         if (!s->s_root) {
2655                 /* initial superblock/root creation */
2656                 mount_info->fill_super(s, mount_info);
2657                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2658                 if (!(server->flags & NFS_MOUNT_UNSHARED))
2659                         s->s_iflags |= SB_I_MULTIROOT;
2660         }
2661
2662         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2663         if (IS_ERR(mntroot))
2664                 goto error_splat_super;
2665
2666         error = mount_info->set_security(s, mntroot, mount_info);
2667         if (error)
2668                 goto error_splat_root;
2669
2670         s->s_flags |= SB_ACTIVE;
2671
2672 out:
2673         return mntroot;
2674
2675 out_err_nosb:
2676         nfs_free_server(server);
2677         goto out;
2678
2679 error_splat_root:
2680         dput(mntroot);
2681         mntroot = ERR_PTR(error);
2682 error_splat_super:
2683         deactivate_locked_super(s);
2684         goto out;
2685 }
2686 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2687
2688 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2689         int flags, const char *dev_name, void *raw_data)
2690 {
2691         struct nfs_mount_info mount_info = {
2692                 .fill_super = nfs_fill_super,
2693                 .set_security = nfs_set_sb_security,
2694         };
2695         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2696         struct nfs_subversion *nfs_mod;
2697         int error;
2698
2699         mount_info.parsed = nfs_alloc_parsed_mount_data();
2700         mount_info.mntfh = nfs_alloc_fhandle();
2701         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2702                 goto out;
2703
2704         /* Validate the mount data */
2705         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2706         if (error == NFS_TEXT_DATA)
2707                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2708         if (error < 0) {
2709                 mntroot = ERR_PTR(error);
2710                 goto out;
2711         }
2712
2713         nfs_mod = get_nfs_version(mount_info.parsed->version);
2714         if (IS_ERR(nfs_mod)) {
2715                 mntroot = ERR_CAST(nfs_mod);
2716                 goto out;
2717         }
2718
2719         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2720
2721         put_nfs_version(nfs_mod);
2722 out:
2723         nfs_free_parsed_mount_data(mount_info.parsed);
2724         nfs_free_fhandle(mount_info.mntfh);
2725         return mntroot;
2726 }
2727 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2728
2729 /*
2730  * Destroy an NFS2/3 superblock
2731  */
2732 void nfs_kill_super(struct super_block *s)
2733 {
2734         struct nfs_server *server = NFS_SB(s);
2735         dev_t dev = s->s_dev;
2736
2737         generic_shutdown_super(s);
2738
2739         nfs_fscache_release_super_cookie(s);
2740
2741         nfs_free_server(server);
2742         free_anon_bdev(dev);
2743 }
2744 EXPORT_SYMBOL_GPL(nfs_kill_super);
2745
2746 /*
2747  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2748  */
2749 static struct dentry *
2750 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2751                 const char *dev_name, void *raw_data)
2752 {
2753         struct nfs_clone_mount *data = raw_data;
2754         struct nfs_mount_info mount_info = {
2755                 .fill_super = nfs_clone_super,
2756                 .set_security = nfs_clone_sb_security,
2757                 .cloned = data,
2758         };
2759         struct nfs_server *server;
2760         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2761         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2762
2763         dprintk("--> nfs_xdev_mount()\n");
2764
2765         mount_info.mntfh = mount_info.cloned->fh;
2766
2767         /* create a new volume representation */
2768         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2769
2770         if (IS_ERR(server))
2771                 mntroot = ERR_CAST(server);
2772         else
2773                 mntroot = nfs_fs_mount_common(server, flags,
2774                                 dev_name, &mount_info, nfs_mod);
2775
2776         dprintk("<-- nfs_xdev_mount() = %ld\n",
2777                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2778         return mntroot;
2779 }
2780
2781 #if IS_ENABLED(CONFIG_NFS_V4)
2782
2783 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2784 {
2785         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2786                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2787 }
2788
2789 /*
2790  * Validate NFSv4 mount options
2791  */
2792 static int nfs4_validate_mount_data(void *options,
2793                                     struct nfs_parsed_mount_data *args,
2794                                     const char *dev_name)
2795 {
2796         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2797         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2798         char *c;
2799
2800         if (data == NULL)
2801                 goto out_no_data;
2802
2803         args->version = 4;
2804
2805         switch (data->version) {
2806         case 1:
2807                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2808                         goto out_no_address;
2809                 if (data->host_addrlen == 0)
2810                         goto out_no_address;
2811                 args->nfs_server.addrlen = data->host_addrlen;
2812                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2813                         return -EFAULT;
2814                 if (!nfs_verify_server_address(sap))
2815                         goto out_no_address;
2816                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2817
2818                 if (data->auth_flavourlen) {
2819                         rpc_authflavor_t pseudoflavor;
2820                         if (data->auth_flavourlen > 1)
2821                                 goto out_inval_auth;
2822                         if (copy_from_user(&pseudoflavor,
2823                                            data->auth_flavours,
2824                                            sizeof(pseudoflavor)))
2825                                 return -EFAULT;
2826                         args->selected_flavor = pseudoflavor;
2827                 } else
2828                         args->selected_flavor = RPC_AUTH_UNIX;
2829
2830                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2831                 if (IS_ERR(c))
2832                         return PTR_ERR(c);
2833                 args->nfs_server.hostname = c;
2834
2835                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2836                 if (IS_ERR(c))
2837                         return PTR_ERR(c);
2838                 args->nfs_server.export_path = c;
2839                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2840
2841                 c = strndup_user(data->client_addr.data, 16);
2842                 if (IS_ERR(c))
2843                         return PTR_ERR(c);
2844                 args->client_address = c;
2845
2846                 /*
2847                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2848                  * can deal with.
2849                  */
2850
2851                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2852                 args->rsize     = data->rsize;
2853                 args->wsize     = data->wsize;
2854                 args->timeo     = data->timeo;
2855                 args->retrans   = data->retrans;
2856                 args->acregmin  = data->acregmin;
2857                 args->acregmax  = data->acregmax;
2858                 args->acdirmin  = data->acdirmin;
2859                 args->acdirmax  = data->acdirmax;
2860                 args->nfs_server.protocol = data->proto;
2861                 nfs_validate_transport_protocol(args);
2862                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2863                         goto out_invalid_transport_udp;
2864
2865                 break;
2866         default:
2867                 return NFS_TEXT_DATA;
2868         }
2869
2870         return 0;
2871
2872 out_no_data:
2873         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2874         return -EINVAL;
2875
2876 out_inval_auth:
2877         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2878                  data->auth_flavourlen);
2879         return -EINVAL;
2880
2881 out_no_address:
2882         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2883         return -EINVAL;
2884
2885 out_invalid_transport_udp:
2886         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2887         return -EINVAL;
2888 }
2889
2890 /*
2891  * NFS v4 module parameters need to stay in the
2892  * NFS client for backwards compatibility
2893  */
2894 unsigned int nfs_callback_set_tcpport;
2895 unsigned short nfs_callback_nr_threads;
2896 /* Default cache timeout is 10 minutes */
2897 unsigned int nfs_idmap_cache_timeout = 600;
2898 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2899 bool nfs4_disable_idmapping = true;
2900 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2901 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
2902 unsigned short send_implementation_id = 1;
2903 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2904 bool recover_lost_locks = false;
2905
2906 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
2907 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2908 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2909 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2910 EXPORT_SYMBOL_GPL(max_session_slots);
2911 EXPORT_SYMBOL_GPL(max_session_cb_slots);
2912 EXPORT_SYMBOL_GPL(send_implementation_id);
2913 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2914 EXPORT_SYMBOL_GPL(recover_lost_locks);
2915
2916 #define NFS_CALLBACK_MAXPORTNR (65535U)
2917
2918 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2919 {
2920         unsigned long num;
2921         int ret;
2922
2923         if (!val)
2924                 return -EINVAL;
2925         ret = kstrtoul(val, 0, &num);
2926         if (ret || num > NFS_CALLBACK_MAXPORTNR)
2927                 return -EINVAL;
2928         *((unsigned int *)kp->arg) = num;
2929         return 0;
2930 }
2931 static const struct kernel_param_ops param_ops_portnr = {
2932         .set = param_set_portnr,
2933         .get = param_get_uint,
2934 };
2935 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2936
2937 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2938 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
2939 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
2940                 "assigned to the NFSv4 callback channels.");
2941 module_param(nfs_idmap_cache_timeout, int, 0644);
2942 module_param(nfs4_disable_idmapping, bool, 0644);
2943 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2944                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2945 MODULE_PARM_DESC(nfs4_disable_idmapping,
2946                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2947 module_param(max_session_slots, ushort, 0644);
2948 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2949                 "requests the client will negotiate");
2950 module_param(max_session_cb_slots, ushort, 0644);
2951 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
2952                 "callbacks the client will process for a given server");
2953 module_param(send_implementation_id, ushort, 0644);
2954 MODULE_PARM_DESC(send_implementation_id,
2955                 "Send implementation ID with NFSv4.1 exchange_id");
2956 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2957
2958 module_param(recover_lost_locks, bool, 0644);
2959 MODULE_PARM_DESC(recover_lost_locks,
2960                  "If the server reports that a lock might be lost, "
2961                  "try to recover it risking data corruption.");
2962
2963
2964 #endif /* CONFIG_NFS_V4 */