linux/fs/nfs/super.c
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   1/*
   2 *  linux/fs/nfs/super.c
   3 *
   4 *  Copyright (C) 1992  Rick Sladkey
   5 *
   6 *  nfs superblock handling functions
   7 *
   8 *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9 *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10 *
  11 *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12 *  J.S.Peatfield@damtp.cam.ac.uk
  13 *
  14 *  Split from inode.c by David Howells <dhowells@redhat.com>
  15 *
  16 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17 *   particular server are held in the same superblock
  18 * - NFS superblocks can have several effective roots to the dentry tree
  19 * - directory type roots are spliced into the tree when a path from one root reaches the root
  20 *   of another (see nfs_lookup())
  21 */
  22
  23#include <linux/module.h>
  24#include <linux/init.h>
  25
  26#include <linux/time.h>
  27#include <linux/kernel.h>
  28#include <linux/mm.h>
  29#include <linux/string.h>
  30#include <linux/stat.h>
  31#include <linux/errno.h>
  32#include <linux/unistd.h>
  33#include <linux/sunrpc/clnt.h>
  34#include <linux/sunrpc/addr.h>
  35#include <linux/sunrpc/stats.h>
  36#include <linux/sunrpc/metrics.h>
  37#include <linux/sunrpc/xprtsock.h>
  38#include <linux/sunrpc/xprtrdma.h>
  39#include <linux/nfs_fs.h>
  40#include <linux/nfs_mount.h>
  41#include <linux/nfs4_mount.h>
  42#include <linux/lockd/bind.h>
  43#include <linux/seq_file.h>
  44#include <linux/mount.h>
  45#include <linux/namei.h>
  46#include <linux/vfs.h>
  47#include <linux/inet.h>
  48#include <linux/in6.h>
  49#include <linux/slab.h>
  50#include <net/ipv6.h>
  51#include <linux/netdevice.h>
  52#include <linux/nfs_xdr.h>
  53#include <linux/magic.h>
  54#include <linux/parser.h>
  55#include <linux/nsproxy.h>
  56#include <linux/rcupdate.h>
  57
  58#include <linux/uaccess.h>
  59
  60#include "nfs4_fs.h"
  61#include "callback.h"
  62#include "delegation.h"
  63#include "iostat.h"
  64#include "internal.h"
  65#include "fscache.h"
  66#include "nfs4session.h"
  67#include "pnfs.h"
  68#include "nfs.h"
  69
  70#define NFSDBG_FACILITY         NFSDBG_VFS
  71#define NFS_TEXT_DATA           1
  72
  73#if IS_ENABLED(CONFIG_NFS_V3)
  74#define NFS_DEFAULT_VERSION 3
  75#else
  76#define NFS_DEFAULT_VERSION 2
  77#endif
  78
  79enum {
  80        /* Mount options that take no arguments */
  81        Opt_soft, Opt_hard,
  82        Opt_posix, Opt_noposix,
  83        Opt_cto, Opt_nocto,
  84        Opt_ac, Opt_noac,
  85        Opt_lock, Opt_nolock,
  86        Opt_udp, Opt_tcp, Opt_rdma,
  87        Opt_acl, Opt_noacl,
  88        Opt_rdirplus, Opt_nordirplus,
  89        Opt_sharecache, Opt_nosharecache,
  90        Opt_resvport, Opt_noresvport,
  91        Opt_fscache, Opt_nofscache,
  92        Opt_migration, Opt_nomigration,
  93
  94        /* Mount options that take integer arguments */
  95        Opt_port,
  96        Opt_rsize, Opt_wsize, Opt_bsize,
  97        Opt_timeo, Opt_retrans,
  98        Opt_acregmin, Opt_acregmax,
  99        Opt_acdirmin, Opt_acdirmax,
 100        Opt_actimeo,
 101        Opt_namelen,
 102        Opt_mountport,
 103        Opt_mountvers,
 104        Opt_minorversion,
 105
 106        /* Mount options that take string arguments */
 107        Opt_nfsvers,
 108        Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 109        Opt_addr, Opt_mountaddr, Opt_clientaddr,
 110        Opt_lookupcache,
 111        Opt_fscache_uniq,
 112        Opt_local_lock,
 113
 114        /* Special mount options */
 115        Opt_userspace, Opt_deprecated, Opt_sloppy,
 116
 117        Opt_err
 118};
 119
 120static const match_table_t nfs_mount_option_tokens = {
 121        { Opt_userspace, "bg" },
 122        { Opt_userspace, "fg" },
 123        { Opt_userspace, "retry=%s" },
 124
 125        { Opt_sloppy, "sloppy" },
 126
 127        { Opt_soft, "soft" },
 128        { Opt_hard, "hard" },
 129        { Opt_deprecated, "intr" },
 130        { Opt_deprecated, "nointr" },
 131        { Opt_posix, "posix" },
 132        { Opt_noposix, "noposix" },
 133        { Opt_cto, "cto" },
 134        { Opt_nocto, "nocto" },
 135        { Opt_ac, "ac" },
 136        { Opt_noac, "noac" },
 137        { Opt_lock, "lock" },
 138        { Opt_nolock, "nolock" },
 139        { Opt_udp, "udp" },
 140        { Opt_tcp, "tcp" },
 141        { Opt_rdma, "rdma" },
 142        { Opt_acl, "acl" },
 143        { Opt_noacl, "noacl" },
 144        { Opt_rdirplus, "rdirplus" },
 145        { Opt_nordirplus, "nordirplus" },
 146        { Opt_sharecache, "sharecache" },
 147        { Opt_nosharecache, "nosharecache" },
 148        { Opt_resvport, "resvport" },
 149        { Opt_noresvport, "noresvport" },
 150        { Opt_fscache, "fsc" },
 151        { Opt_nofscache, "nofsc" },
 152        { Opt_migration, "migration" },
 153        { Opt_nomigration, "nomigration" },
 154
 155        { Opt_port, "port=%s" },
 156        { Opt_rsize, "rsize=%s" },
 157        { Opt_wsize, "wsize=%s" },
 158        { Opt_bsize, "bsize=%s" },
 159        { Opt_timeo, "timeo=%s" },
 160        { Opt_retrans, "retrans=%s" },
 161        { Opt_acregmin, "acregmin=%s" },
 162        { Opt_acregmax, "acregmax=%s" },
 163        { Opt_acdirmin, "acdirmin=%s" },
 164        { Opt_acdirmax, "acdirmax=%s" },
 165        { Opt_actimeo, "actimeo=%s" },
 166        { Opt_namelen, "namlen=%s" },
 167        { Opt_mountport, "mountport=%s" },
 168        { Opt_mountvers, "mountvers=%s" },
 169        { Opt_minorversion, "minorversion=%s" },
 170
 171        { Opt_nfsvers, "nfsvers=%s" },
 172        { Opt_nfsvers, "vers=%s" },
 173
 174        { Opt_sec, "sec=%s" },
 175        { Opt_proto, "proto=%s" },
 176        { Opt_mountproto, "mountproto=%s" },
 177        { Opt_addr, "addr=%s" },
 178        { Opt_clientaddr, "clientaddr=%s" },
 179        { Opt_mounthost, "mounthost=%s" },
 180        { Opt_mountaddr, "mountaddr=%s" },
 181
 182        { Opt_lookupcache, "lookupcache=%s" },
 183        { Opt_fscache_uniq, "fsc=%s" },
 184        { Opt_local_lock, "local_lock=%s" },
 185
 186        /* The following needs to be listed after all other options */
 187        { Opt_nfsvers, "v%s" },
 188
 189        { Opt_err, NULL }
 190};
 191
 192enum {
 193        Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 194        Opt_xprt_rdma6,
 195
 196        Opt_xprt_err
 197};
 198
 199static const match_table_t nfs_xprt_protocol_tokens = {
 200        { Opt_xprt_udp, "udp" },
 201        { Opt_xprt_udp6, "udp6" },
 202        { Opt_xprt_tcp, "tcp" },
 203        { Opt_xprt_tcp6, "tcp6" },
 204        { Opt_xprt_rdma, "rdma" },
 205        { Opt_xprt_rdma6, "rdma6" },
 206
 207        { Opt_xprt_err, NULL }
 208};
 209
 210enum {
 211        Opt_sec_none, Opt_sec_sys,
 212        Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 213        Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 214        Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 215
 216        Opt_sec_err
 217};
 218
 219static const match_table_t nfs_secflavor_tokens = {
 220        { Opt_sec_none, "none" },
 221        { Opt_sec_none, "null" },
 222        { Opt_sec_sys, "sys" },
 223
 224        { Opt_sec_krb5, "krb5" },
 225        { Opt_sec_krb5i, "krb5i" },
 226        { Opt_sec_krb5p, "krb5p" },
 227
 228        { Opt_sec_lkey, "lkey" },
 229        { Opt_sec_lkeyi, "lkeyi" },
 230        { Opt_sec_lkeyp, "lkeyp" },
 231
 232        { Opt_sec_spkm, "spkm3" },
 233        { Opt_sec_spkmi, "spkm3i" },
 234        { Opt_sec_spkmp, "spkm3p" },
 235
 236        { Opt_sec_err, NULL }
 237};
 238
 239enum {
 240        Opt_lookupcache_all, Opt_lookupcache_positive,
 241        Opt_lookupcache_none,
 242
 243        Opt_lookupcache_err
 244};
 245
 246static match_table_t nfs_lookupcache_tokens = {
 247        { Opt_lookupcache_all, "all" },
 248        { Opt_lookupcache_positive, "pos" },
 249        { Opt_lookupcache_positive, "positive" },
 250        { Opt_lookupcache_none, "none" },
 251
 252        { Opt_lookupcache_err, NULL }
 253};
 254
 255enum {
 256        Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 257        Opt_local_lock_none,
 258
 259        Opt_local_lock_err
 260};
 261
 262static match_table_t nfs_local_lock_tokens = {
 263        { Opt_local_lock_all, "all" },
 264        { Opt_local_lock_flock, "flock" },
 265        { Opt_local_lock_posix, "posix" },
 266        { Opt_local_lock_none, "none" },
 267
 268        { Opt_local_lock_err, NULL }
 269};
 270
 271enum {
 272        Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 273        Opt_vers_4_1, Opt_vers_4_2,
 274
 275        Opt_vers_err
 276};
 277
 278static match_table_t nfs_vers_tokens = {
 279        { Opt_vers_2, "2" },
 280        { Opt_vers_3, "3" },
 281        { Opt_vers_4, "4" },
 282        { Opt_vers_4_0, "4.0" },
 283        { Opt_vers_4_1, "4.1" },
 284        { Opt_vers_4_2, "4.2" },
 285
 286        { Opt_vers_err, NULL }
 287};
 288
 289static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 290                int flags, const char *dev_name, void *raw_data);
 291
 292struct file_system_type nfs_fs_type = {
 293        .owner          = THIS_MODULE,
 294        .name           = "nfs",
 295        .mount          = nfs_fs_mount,
 296        .kill_sb        = nfs_kill_super,
 297        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 298};
 299MODULE_ALIAS_FS("nfs");
 300EXPORT_SYMBOL_GPL(nfs_fs_type);
 301
 302struct file_system_type nfs_xdev_fs_type = {
 303        .owner          = THIS_MODULE,
 304        .name           = "nfs",
 305        .mount          = nfs_xdev_mount,
 306        .kill_sb        = nfs_kill_super,
 307        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 308};
 309
 310const struct super_operations nfs_sops = {
 311        .alloc_inode    = nfs_alloc_inode,
 312        .destroy_inode  = nfs_destroy_inode,
 313        .write_inode    = nfs_write_inode,
 314        .drop_inode     = nfs_drop_inode,
 315        .statfs         = nfs_statfs,
 316        .evict_inode    = nfs_evict_inode,
 317        .umount_begin   = nfs_umount_begin,
 318        .show_options   = nfs_show_options,
 319        .show_devname   = nfs_show_devname,
 320        .show_path      = nfs_show_path,
 321        .show_stats     = nfs_show_stats,
 322        .remount_fs     = nfs_remount,
 323};
 324EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326#if IS_ENABLED(CONFIG_NFS_V4)
 327static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328static int nfs4_validate_mount_data(void *options,
 329        struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331struct file_system_type nfs4_fs_type = {
 332        .owner          = THIS_MODULE,
 333        .name           = "nfs4",
 334        .mount          = nfs_fs_mount,
 335        .kill_sb        = nfs_kill_super,
 336        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337};
 338MODULE_ALIAS_FS("nfs4");
 339MODULE_ALIAS("nfs4");
 340EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342static int __init register_nfs4_fs(void)
 343{
 344        return register_filesystem(&nfs4_fs_type);
 345}
 346
 347static void unregister_nfs4_fs(void)
 348{
 349        unregister_filesystem(&nfs4_fs_type);
 350}
 351#else
 352static int __init register_nfs4_fs(void)
 353{
 354        return 0;
 355}
 356
 357static void unregister_nfs4_fs(void)
 358{
 359}
 360#endif
 361
 362static struct shrinker acl_shrinker = {
 363        .count_objects  = nfs_access_cache_count,
 364        .scan_objects   = nfs_access_cache_scan,
 365        .seeks          = DEFAULT_SEEKS,
 366};
 367
 368/*
 369 * Register the NFS filesystems
 370 */
 371int __init register_nfs_fs(void)
 372{
 373        int ret;
 374
 375        ret = register_filesystem(&nfs_fs_type);
 376        if (ret < 0)
 377                goto error_0;
 378
 379        ret = register_nfs4_fs();
 380        if (ret < 0)
 381                goto error_1;
 382
 383        ret = nfs_register_sysctl();
 384        if (ret < 0)
 385                goto error_2;
 386        ret = register_shrinker(&acl_shrinker);
 387        if (ret < 0)
 388                goto error_3;
 389        return 0;
 390error_3:
 391        nfs_unregister_sysctl();
 392error_2:
 393        unregister_nfs4_fs();
 394error_1:
 395        unregister_filesystem(&nfs_fs_type);
 396error_0:
 397        return ret;
 398}
 399
 400/*
 401 * Unregister the NFS filesystems
 402 */
 403void __exit unregister_nfs_fs(void)
 404{
 405        unregister_shrinker(&acl_shrinker);
 406        nfs_unregister_sysctl();
 407        unregister_nfs4_fs();
 408        unregister_filesystem(&nfs_fs_type);
 409}
 410
 411bool nfs_sb_active(struct super_block *sb)
 412{
 413        struct nfs_server *server = NFS_SB(sb);
 414
 415        if (!atomic_inc_not_zero(&sb->s_active))
 416                return false;
 417        if (atomic_inc_return(&server->active) != 1)
 418                atomic_dec(&sb->s_active);
 419        return true;
 420}
 421EXPORT_SYMBOL_GPL(nfs_sb_active);
 422
 423void nfs_sb_deactive(struct super_block *sb)
 424{
 425        struct nfs_server *server = NFS_SB(sb);
 426
 427        if (atomic_dec_and_test(&server->active))
 428                deactivate_super(sb);
 429}
 430EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 431
 432/*
 433 * Deliver file system statistics to userspace
 434 */
 435int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 436{
 437        struct nfs_server *server = NFS_SB(dentry->d_sb);
 438        unsigned char blockbits;
 439        unsigned long blockres;
 440        struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 441        struct nfs_fsstat res;
 442        int error = -ENOMEM;
 443
 444        res.fattr = nfs_alloc_fattr();
 445        if (res.fattr == NULL)
 446                goto out_err;
 447
 448        error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 449        if (unlikely(error == -ESTALE)) {
 450                struct dentry *pd_dentry;
 451
 452                pd_dentry = dget_parent(dentry);
 453                if (pd_dentry != NULL) {
 454                        nfs_zap_caches(d_inode(pd_dentry));
 455                        dput(pd_dentry);
 456                }
 457        }
 458        nfs_free_fattr(res.fattr);
 459        if (error < 0)
 460                goto out_err;
 461
 462        buf->f_type = NFS_SUPER_MAGIC;
 463
 464        /*
 465         * Current versions of glibc do not correctly handle the
 466         * case where f_frsize != f_bsize.  Eventually we want to
 467         * report the value of wtmult in this field.
 468         */
 469        buf->f_frsize = dentry->d_sb->s_blocksize;
 470
 471        /*
 472         * On most *nix systems, f_blocks, f_bfree, and f_bavail
 473         * are reported in units of f_frsize.  Linux hasn't had
 474         * an f_frsize field in its statfs struct until recently,
 475         * thus historically Linux's sys_statfs reports these
 476         * fields in units of f_bsize.
 477         */
 478        buf->f_bsize = dentry->d_sb->s_blocksize;
 479        blockbits = dentry->d_sb->s_blocksize_bits;
 480        blockres = (1 << blockbits) - 1;
 481        buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 482        buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 483        buf->f_bavail = (res.abytes + blockres) >> blockbits;
 484
 485        buf->f_files = res.tfiles;
 486        buf->f_ffree = res.afiles;
 487
 488        buf->f_namelen = server->namelen;
 489
 490        return 0;
 491
 492 out_err:
 493        dprintk("%s: statfs error = %d\n", __func__, -error);
 494        return error;
 495}
 496EXPORT_SYMBOL_GPL(nfs_statfs);
 497
 498/*
 499 * Map the security flavour number to a name
 500 */
 501static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 502{
 503        static const struct {
 504                rpc_authflavor_t flavour;
 505                const char *str;
 506        } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 507                /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 508                { RPC_AUTH_NULL, "null" },
 509                { RPC_AUTH_UNIX, "sys" },
 510                { RPC_AUTH_GSS_KRB5, "krb5" },
 511                { RPC_AUTH_GSS_KRB5I, "krb5i" },
 512                { RPC_AUTH_GSS_KRB5P, "krb5p" },
 513                { RPC_AUTH_GSS_LKEY, "lkey" },
 514                { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 515                { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 516                { RPC_AUTH_GSS_SPKM, "spkm" },
 517                { RPC_AUTH_GSS_SPKMI, "spkmi" },
 518                { RPC_AUTH_GSS_SPKMP, "spkmp" },
 519                { UINT_MAX, "unknown" }
 520        };
 521        int i;
 522
 523        for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 524                if (sec_flavours[i].flavour == flavour)
 525                        break;
 526        }
 527        return sec_flavours[i].str;
 528}
 529
 530static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 531                                  int showdefaults)
 532{
 533        struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 534        char *proto = NULL;
 535
 536        switch (sap->sa_family) {
 537        case AF_INET:
 538                switch (nfss->mountd_protocol) {
 539                case IPPROTO_UDP:
 540                        proto = RPCBIND_NETID_UDP;
 541                        break;
 542                case IPPROTO_TCP:
 543                        proto = RPCBIND_NETID_TCP;
 544                        break;
 545                }
 546                break;
 547        case AF_INET6:
 548                switch (nfss->mountd_protocol) {
 549                case IPPROTO_UDP:
 550                        proto = RPCBIND_NETID_UDP6;
 551                        break;
 552                case IPPROTO_TCP:
 553                        proto = RPCBIND_NETID_TCP6;
 554                        break;
 555                }
 556                break;
 557        }
 558        if (proto || showdefaults)
 559                seq_printf(m, ",mountproto=%s", proto ?: "auto");
 560}
 561
 562static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 563                                    int showdefaults)
 564{
 565        struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 566
 567        if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 568                return;
 569
 570        switch (sap->sa_family) {
 571        case AF_INET: {
 572                struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 573                seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 574                break;
 575        }
 576        case AF_INET6: {
 577                struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 578                seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 579                break;
 580        }
 581        default:
 582                if (showdefaults)
 583                        seq_printf(m, ",mountaddr=unspecified");
 584        }
 585
 586        if (nfss->mountd_version || showdefaults)
 587                seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 588        if ((nfss->mountd_port &&
 589                nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 590                showdefaults)
 591                seq_printf(m, ",mountport=%u", nfss->mountd_port);
 592
 593        nfs_show_mountd_netid(m, nfss, showdefaults);
 594}
 595
 596#if IS_ENABLED(CONFIG_NFS_V4)
 597static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 598                                    int showdefaults)
 599{
 600        struct nfs_client *clp = nfss->nfs_client;
 601
 602        seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 603}
 604#else
 605static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 606                                    int showdefaults)
 607{
 608}
 609#endif
 610
 611static void nfs_show_nfs_version(struct seq_file *m,
 612                unsigned int version,
 613                unsigned int minorversion)
 614{
 615        seq_printf(m, ",vers=%u", version);
 616        if (version == 4)
 617                seq_printf(m, ".%u", minorversion);
 618}
 619
 620/*
 621 * Describe the mount options in force on this server representation
 622 */
 623static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 624                                   int showdefaults)
 625{
 626        static const struct proc_nfs_info {
 627                int flag;
 628                const char *str;
 629                const char *nostr;
 630        } nfs_info[] = {
 631                { NFS_MOUNT_SOFT, ",soft", ",hard" },
 632                { NFS_MOUNT_POSIX, ",posix", "" },
 633                { NFS_MOUNT_NOCTO, ",nocto", "" },
 634                { NFS_MOUNT_NOAC, ",noac", "" },
 635                { NFS_MOUNT_NONLM, ",nolock", "" },
 636                { NFS_MOUNT_NOACL, ",noacl", "" },
 637                { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 638                { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 639                { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 640                { 0, NULL, NULL }
 641        };
 642        const struct proc_nfs_info *nfs_infop;
 643        struct nfs_client *clp = nfss->nfs_client;
 644        u32 version = clp->rpc_ops->version;
 645        int local_flock, local_fcntl;
 646
 647        nfs_show_nfs_version(m, version, clp->cl_minorversion);
 648        seq_printf(m, ",rsize=%u", nfss->rsize);
 649        seq_printf(m, ",wsize=%u", nfss->wsize);
 650        if (nfss->bsize != 0)
 651                seq_printf(m, ",bsize=%u", nfss->bsize);
 652        seq_printf(m, ",namlen=%u", nfss->namelen);
 653        if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 654                seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 655        if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 656                seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 657        if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 658                seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 659        if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 660                seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 661        for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 662                if (nfss->flags & nfs_infop->flag)
 663                        seq_puts(m, nfs_infop->str);
 664                else
 665                        seq_puts(m, nfs_infop->nostr);
 666        }
 667        rcu_read_lock();
 668        seq_printf(m, ",proto=%s",
 669                   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 670        rcu_read_unlock();
 671        if (version == 4) {
 672                if (nfss->port != NFS_PORT)
 673                        seq_printf(m, ",port=%u", nfss->port);
 674        } else
 675                if (nfss->port)
 676                        seq_printf(m, ",port=%u", nfss->port);
 677
 678        seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 679        seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 680        seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 681
 682        if (version != 4)
 683                nfs_show_mountd_options(m, nfss, showdefaults);
 684        else
 685                nfs_show_nfsv4_options(m, nfss, showdefaults);
 686
 687        if (nfss->options & NFS_OPTION_FSCACHE)
 688                seq_printf(m, ",fsc");
 689
 690        if (nfss->options & NFS_OPTION_MIGRATION)
 691                seq_printf(m, ",migration");
 692
 693        if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 694                if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 695                        seq_printf(m, ",lookupcache=none");
 696                else
 697                        seq_printf(m, ",lookupcache=pos");
 698        }
 699
 700        local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 701        local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 702
 703        if (!local_flock && !local_fcntl)
 704                seq_printf(m, ",local_lock=none");
 705        else if (local_flock && local_fcntl)
 706                seq_printf(m, ",local_lock=all");
 707        else if (local_flock)
 708                seq_printf(m, ",local_lock=flock");
 709        else
 710                seq_printf(m, ",local_lock=posix");
 711}
 712
 713/*
 714 * Describe the mount options on this VFS mountpoint
 715 */
 716int nfs_show_options(struct seq_file *m, struct dentry *root)
 717{
 718        struct nfs_server *nfss = NFS_SB(root->d_sb);
 719
 720        nfs_show_mount_options(m, nfss, 0);
 721
 722        rcu_read_lock();
 723        seq_printf(m, ",addr=%s",
 724                        rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 725                                                        RPC_DISPLAY_ADDR));
 726        rcu_read_unlock();
 727
 728        return 0;
 729}
 730EXPORT_SYMBOL_GPL(nfs_show_options);
 731
 732#if IS_ENABLED(CONFIG_NFS_V4)
 733#ifdef CONFIG_NFS_V4_1
 734static void show_sessions(struct seq_file *m, struct nfs_server *server)
 735{
 736        if (nfs4_has_session(server->nfs_client))
 737                seq_printf(m, ",sessions");
 738}
 739#else
 740static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 741#endif
 742#endif
 743
 744#ifdef CONFIG_NFS_V4_1
 745static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 746{
 747        seq_printf(m, ",pnfs=");
 748        if (server->pnfs_curr_ld)
 749                seq_printf(m, "%s", server->pnfs_curr_ld->name);
 750        else
 751                seq_printf(m, "not configured");
 752}
 753
 754static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 755{
 756        if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 757                struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 758                seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 759                           "date='%llu,%u'",
 760                           impl_id->name, impl_id->domain,
 761                           impl_id->date.seconds, impl_id->date.nseconds);
 762        }
 763}
 764#else
 765#if IS_ENABLED(CONFIG_NFS_V4)
 766static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 767{
 768}
 769#endif
 770static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 771{
 772}
 773#endif
 774
 775int nfs_show_devname(struct seq_file *m, struct dentry *root)
 776{
 777        char *page = (char *) __get_free_page(GFP_KERNEL);
 778        char *devname, *dummy;
 779        int err = 0;
 780        if (!page)
 781                return -ENOMEM;
 782        devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 783        if (IS_ERR(devname))
 784                err = PTR_ERR(devname);
 785        else
 786                seq_escape(m, devname, " \t\n\\");
 787        free_page((unsigned long)page);
 788        return err;
 789}
 790EXPORT_SYMBOL_GPL(nfs_show_devname);
 791
 792int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 793{
 794        seq_puts(m, "/");
 795        return 0;
 796}
 797EXPORT_SYMBOL_GPL(nfs_show_path);
 798
 799/*
 800 * Present statistical information for this VFS mountpoint
 801 */
 802int nfs_show_stats(struct seq_file *m, struct dentry *root)
 803{
 804        int i, cpu;
 805        struct nfs_server *nfss = NFS_SB(root->d_sb);
 806        struct rpc_auth *auth = nfss->client->cl_auth;
 807        struct nfs_iostats totals = { };
 808
 809        seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 810
 811        /*
 812         * Display all mount option settings
 813         */
 814        seq_printf(m, "\n\topts:\t");
 815        seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
 816        seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
 817        seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
 818        seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
 819        nfs_show_mount_options(m, nfss, 1);
 820
 821        seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 822
 823        show_implementation_id(m, nfss);
 824
 825        seq_printf(m, "\n\tcaps:\t");
 826        seq_printf(m, "caps=0x%x", nfss->caps);
 827        seq_printf(m, ",wtmult=%u", nfss->wtmult);
 828        seq_printf(m, ",dtsize=%u", nfss->dtsize);
 829        seq_printf(m, ",bsize=%u", nfss->bsize);
 830        seq_printf(m, ",namlen=%u", nfss->namelen);
 831
 832#if IS_ENABLED(CONFIG_NFS_V4)
 833        if (nfss->nfs_client->rpc_ops->version == 4) {
 834                seq_printf(m, "\n\tnfsv4:\t");
 835                seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 836                seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 837                seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 838                seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 839                show_sessions(m, nfss);
 840                show_pnfs(m, nfss);
 841        }
 842#endif
 843
 844        /*
 845         * Display security flavor in effect for this mount
 846         */
 847        seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 848        if (auth->au_flavor)
 849                seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 850
 851        /*
 852         * Display superblock I/O counters
 853         */
 854        for_each_possible_cpu(cpu) {
 855                struct nfs_iostats *stats;
 856
 857                preempt_disable();
 858                stats = per_cpu_ptr(nfss->io_stats, cpu);
 859
 860                for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 861                        totals.events[i] += stats->events[i];
 862                for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 863                        totals.bytes[i] += stats->bytes[i];
 864#ifdef CONFIG_NFS_FSCACHE
 865                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 866                        totals.fscache[i] += stats->fscache[i];
 867#endif
 868
 869                preempt_enable();
 870        }
 871
 872        seq_printf(m, "\n\tevents:\t");
 873        for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 874                seq_printf(m, "%lu ", totals.events[i]);
 875        seq_printf(m, "\n\tbytes:\t");
 876        for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 877                seq_printf(m, "%Lu ", totals.bytes[i]);
 878#ifdef CONFIG_NFS_FSCACHE
 879        if (nfss->options & NFS_OPTION_FSCACHE) {
 880                seq_printf(m, "\n\tfsc:\t");
 881                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 882                        seq_printf(m, "%Lu ", totals.fscache[i]);
 883        }
 884#endif
 885        seq_printf(m, "\n");
 886
 887        rpc_print_iostats(m, nfss->client);
 888
 889        return 0;
 890}
 891EXPORT_SYMBOL_GPL(nfs_show_stats);
 892
 893/*
 894 * Begin unmount by attempting to remove all automounted mountpoints we added
 895 * in response to xdev traversals and referrals
 896 */
 897void nfs_umount_begin(struct super_block *sb)
 898{
 899        struct nfs_server *server;
 900        struct rpc_clnt *rpc;
 901
 902        server = NFS_SB(sb);
 903        /* -EIO all pending I/O */
 904        rpc = server->client_acl;
 905        if (!IS_ERR(rpc))
 906                rpc_killall_tasks(rpc);
 907        rpc = server->client;
 908        if (!IS_ERR(rpc))
 909                rpc_killall_tasks(rpc);
 910}
 911EXPORT_SYMBOL_GPL(nfs_umount_begin);
 912
 913static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 914{
 915        struct nfs_parsed_mount_data *data;
 916
 917        data = kzalloc(sizeof(*data), GFP_KERNEL);
 918        if (data) {
 919                data->timeo             = NFS_UNSPEC_TIMEO;
 920                data->retrans           = NFS_UNSPEC_RETRANS;
 921                data->acregmin          = NFS_DEF_ACREGMIN;
 922                data->acregmax          = NFS_DEF_ACREGMAX;
 923                data->acdirmin          = NFS_DEF_ACDIRMIN;
 924                data->acdirmax          = NFS_DEF_ACDIRMAX;
 925                data->mount_server.port = NFS_UNSPEC_PORT;
 926                data->nfs_server.port   = NFS_UNSPEC_PORT;
 927                data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 928                data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 929                data->minorversion      = 0;
 930                data->need_mount        = true;
 931                data->net               = current->nsproxy->net_ns;
 932                security_init_mnt_opts(&data->lsm_opts);
 933        }
 934        return data;
 935}
 936
 937static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 938{
 939        if (data) {
 940                kfree(data->client_address);
 941                kfree(data->mount_server.hostname);
 942                kfree(data->nfs_server.export_path);
 943                kfree(data->nfs_server.hostname);
 944                kfree(data->fscache_uniq);
 945                security_free_mnt_opts(&data->lsm_opts);
 946                kfree(data);
 947        }
 948}
 949
 950/*
 951 * Sanity-check a server address provided by the mount command.
 952 *
 953 * Address family must be initialized, and address must not be
 954 * the ANY address for that family.
 955 */
 956static int nfs_verify_server_address(struct sockaddr *addr)
 957{
 958        switch (addr->sa_family) {
 959        case AF_INET: {
 960                struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 961                return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 962        }
 963        case AF_INET6: {
 964                struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 965                return !ipv6_addr_any(sa);
 966        }
 967        }
 968
 969        dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 970        return 0;
 971}
 972
 973/*
 974 * Select between a default port value and a user-specified port value.
 975 * If a zero value is set, then autobind will be used.
 976 */
 977static void nfs_set_port(struct sockaddr *sap, int *port,
 978                                 const unsigned short default_port)
 979{
 980        if (*port == NFS_UNSPEC_PORT)
 981                *port = default_port;
 982
 983        rpc_set_port(sap, *port);
 984}
 985
 986/*
 987 * Sanity check the NFS transport protocol.
 988 *
 989 */
 990static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 991{
 992        switch (mnt->nfs_server.protocol) {
 993        case XPRT_TRANSPORT_UDP:
 994        case XPRT_TRANSPORT_TCP:
 995        case XPRT_TRANSPORT_RDMA:
 996                break;
 997        default:
 998                mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 999        }
1000}
1001
1002/*
1003 * For text based NFSv2/v3 mounts, the mount protocol transport default
1004 * settings should depend upon the specified NFS transport.
1005 */
1006static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1007{
1008        nfs_validate_transport_protocol(mnt);
1009
1010        if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1011            mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1012                        return;
1013        switch (mnt->nfs_server.protocol) {
1014        case XPRT_TRANSPORT_UDP:
1015                mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1016                break;
1017        case XPRT_TRANSPORT_TCP:
1018        case XPRT_TRANSPORT_RDMA:
1019                mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1020        }
1021}
1022
1023/*
1024 * Add 'flavor' to 'auth_info' if not already present.
1025 * Returns true if 'flavor' ends up in the list, false otherwise
1026 */
1027static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1028                              rpc_authflavor_t flavor)
1029{
1030        unsigned int i;
1031        unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1032
1033        /* make sure this flavor isn't already in the list */
1034        for (i = 0; i < auth_info->flavor_len; i++) {
1035                if (flavor == auth_info->flavors[i])
1036                        return true;
1037        }
1038
1039        if (auth_info->flavor_len + 1 >= max_flavor_len) {
1040                dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1041                return false;
1042        }
1043
1044        auth_info->flavors[auth_info->flavor_len++] = flavor;
1045        return true;
1046}
1047
1048/*
1049 * Return true if 'match' is in auth_info or auth_info is empty.
1050 * Return false otherwise.
1051 */
1052bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1053                         rpc_authflavor_t match)
1054{
1055        int i;
1056
1057        if (!auth_info->flavor_len)
1058                return true;
1059
1060        for (i = 0; i < auth_info->flavor_len; i++) {
1061                if (auth_info->flavors[i] == match)
1062                        return true;
1063        }
1064        return false;
1065}
1066EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1067
1068/*
1069 * Parse the value of the 'sec=' option.
1070 */
1071static int nfs_parse_security_flavors(char *value,
1072                                      struct nfs_parsed_mount_data *mnt)
1073{
1074        substring_t args[MAX_OPT_ARGS];
1075        rpc_authflavor_t pseudoflavor;
1076        char *p;
1077
1078        dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1079
1080        while ((p = strsep(&value, ":")) != NULL) {
1081                switch (match_token(p, nfs_secflavor_tokens, args)) {
1082                case Opt_sec_none:
1083                        pseudoflavor = RPC_AUTH_NULL;
1084                        break;
1085                case Opt_sec_sys:
1086                        pseudoflavor = RPC_AUTH_UNIX;
1087                        break;
1088                case Opt_sec_krb5:
1089                        pseudoflavor = RPC_AUTH_GSS_KRB5;
1090                        break;
1091                case Opt_sec_krb5i:
1092                        pseudoflavor = RPC_AUTH_GSS_KRB5I;
1093                        break;
1094                case Opt_sec_krb5p:
1095                        pseudoflavor = RPC_AUTH_GSS_KRB5P;
1096                        break;
1097                case Opt_sec_lkey:
1098                        pseudoflavor = RPC_AUTH_GSS_LKEY;
1099                        break;
1100                case Opt_sec_lkeyi:
1101                        pseudoflavor = RPC_AUTH_GSS_LKEYI;
1102                        break;
1103                case Opt_sec_lkeyp:
1104                        pseudoflavor = RPC_AUTH_GSS_LKEYP;
1105                        break;
1106                case Opt_sec_spkm:
1107                        pseudoflavor = RPC_AUTH_GSS_SPKM;
1108                        break;
1109                case Opt_sec_spkmi:
1110                        pseudoflavor = RPC_AUTH_GSS_SPKMI;
1111                        break;
1112                case Opt_sec_spkmp:
1113                        pseudoflavor = RPC_AUTH_GSS_SPKMP;
1114                        break;
1115                default:
1116                        dfprintk(MOUNT,
1117                                 "NFS: sec= option '%s' not recognized\n", p);
1118                        return 0;
1119                }
1120
1121                if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1122                        return 0;
1123        }
1124
1125        return 1;
1126}
1127
1128static int nfs_parse_version_string(char *string,
1129                struct nfs_parsed_mount_data *mnt,
1130                substring_t *args)
1131{
1132        mnt->flags &= ~NFS_MOUNT_VER3;
1133        switch (match_token(string, nfs_vers_tokens, args)) {
1134        case Opt_vers_2:
1135                mnt->version = 2;
1136                break;
1137        case Opt_vers_3:
1138                mnt->flags |= NFS_MOUNT_VER3;
1139                mnt->version = 3;
1140                break;
1141        case Opt_vers_4:
1142                /* Backward compatibility option. In future,
1143                 * the mount program should always supply
1144                 * a NFSv4 minor version number.
1145                 */
1146                mnt->version = 4;
1147                break;
1148        case Opt_vers_4_0:
1149                mnt->version = 4;
1150                mnt->minorversion = 0;
1151                break;
1152        case Opt_vers_4_1:
1153                mnt->version = 4;
1154                mnt->minorversion = 1;
1155                break;
1156        case Opt_vers_4_2:
1157                mnt->version = 4;
1158                mnt->minorversion = 2;
1159                break;
1160        default:
1161                return 0;
1162        }
1163        return 1;
1164}
1165
1166static int nfs_get_option_str(substring_t args[], char **option)
1167{
1168        kfree(*option);
1169        *option = match_strdup(args);
1170        return !*option;
1171}
1172
1173static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1174{
1175        int rc;
1176        char *string;
1177
1178        string = match_strdup(args);
1179        if (string == NULL)
1180                return -ENOMEM;
1181        rc = kstrtoul(string, 10, option);
1182        kfree(string);
1183
1184        return rc;
1185}
1186
1187static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1188                unsigned long l_bound, unsigned long u_bound)
1189{
1190        int ret;
1191
1192        ret = nfs_get_option_ul(args, option);
1193        if (ret != 0)
1194                return ret;
1195        if (*option < l_bound || *option > u_bound)
1196                return -ERANGE;
1197        return 0;
1198}
1199
1200/*
1201 * Error-check and convert a string of mount options from user space into
1202 * a data structure.  The whole mount string is processed; bad options are
1203 * skipped as they are encountered.  If there were no errors, return 1;
1204 * otherwise return 0 (zero).
1205 */
1206static int nfs_parse_mount_options(char *raw,
1207                                   struct nfs_parsed_mount_data *mnt)
1208{
1209        char *p, *string, *secdata;
1210        int rc, sloppy = 0, invalid_option = 0;
1211        unsigned short protofamily = AF_UNSPEC;
1212        unsigned short mountfamily = AF_UNSPEC;
1213
1214        if (!raw) {
1215                dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1216                return 1;
1217        }
1218        dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1219
1220        secdata = alloc_secdata();
1221        if (!secdata)
1222                goto out_nomem;
1223
1224        rc = security_sb_copy_data(raw, secdata);
1225        if (rc)
1226                goto out_security_failure;
1227
1228        rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1229        if (rc)
1230                goto out_security_failure;
1231
1232        free_secdata(secdata);
1233
1234        while ((p = strsep(&raw, ",")) != NULL) {
1235                substring_t args[MAX_OPT_ARGS];
1236                unsigned long option;
1237                int token;
1238
1239                if (!*p)
1240                        continue;
1241
1242                dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1243
1244                token = match_token(p, nfs_mount_option_tokens, args);
1245                switch (token) {
1246
1247                /*
1248                 * boolean options:  foo/nofoo
1249                 */
1250                case Opt_soft:
1251                        mnt->flags |= NFS_MOUNT_SOFT;
1252                        break;
1253                case Opt_hard:
1254                        mnt->flags &= ~NFS_MOUNT_SOFT;
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
1660out_mountproto_mismatch:
1661        printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1662                         "option\n");
1663        return 0;
1664out_proto_mismatch:
1665        printk(KERN_INFO "NFS: server address does not match proto= option\n");
1666        return 0;
1667out_invalid_address:
1668        printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1669        return 0;
1670out_invalid_value:
1671        printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1672        return 0;
1673out_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;
1677out_migration_misuse:
1678        printk(KERN_INFO
1679                "NFS: 'migration' not supported for this NFS version\n");
1680        return 0;
1681out_nomem:
1682        printk(KERN_INFO "NFS: not enough memory to parse option\n");
1683        return 0;
1684out_security_failure:
1685        free_secdata(secdata);
1686        printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1687        return 0;
1688}
1689
1690/*
1691 * Ensure that a specified authtype in args->auth_info is supported by
1692 * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1693 * -EACCES if not.
1694 */
1695static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1696                        rpc_authflavor_t *server_authlist, unsigned int count)
1697{
1698        rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1699        bool found_auth_null = false;
1700        unsigned int i;
1701
1702        /*
1703         * If the sec= mount option is used, the specified flavor or AUTH_NULL
1704         * must be in the list returned by the server.
1705         *
1706         * AUTH_NULL has a special meaning when it's in the server list - it
1707         * means that the server will ignore the rpc creds, so any flavor
1708         * can be used but still use the sec= that was specified.
1709         *
1710         * Note also that the MNT procedure in MNTv1 does not return a list
1711         * of supported security flavors. In this case, nfs_mount() fabricates
1712         * a security flavor list containing just AUTH_NULL.
1713         */
1714        for (i = 0; i < count; i++) {
1715                flavor = server_authlist[i];
1716
1717                if (nfs_auth_info_match(&args->auth_info, flavor))
1718                        goto out;
1719
1720                if (flavor == RPC_AUTH_NULL)
1721                        found_auth_null = true;
1722        }
1723
1724        if (found_auth_null) {
1725                flavor = args->auth_info.flavors[0];
1726                goto out;
1727        }
1728
1729        dfprintk(MOUNT,
1730                 "NFS: specified auth flavors not supported by server\n");
1731        return -EACCES;
1732
1733out:
1734        args->selected_flavor = flavor;
1735        dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1736        return 0;
1737}
1738
1739/*
1740 * Use the remote server's MOUNT service to request the NFS file handle
1741 * corresponding to the provided path.
1742 */
1743static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1744                             struct nfs_fh *root_fh,
1745                             rpc_authflavor_t *server_authlist,
1746                             unsigned int *server_authlist_len)
1747{
1748        struct nfs_mount_request request = {
1749                .sap            = (struct sockaddr *)
1750                                                &args->mount_server.address,
1751                .dirpath        = args->nfs_server.export_path,
1752                .protocol       = args->mount_server.protocol,
1753                .fh             = root_fh,
1754                .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1755                .auth_flav_len  = server_authlist_len,
1756                .auth_flavs     = server_authlist,
1757                .net            = args->net,
1758        };
1759        int status;
1760
1761        if (args->mount_server.version == 0) {
1762                switch (args->version) {
1763                        default:
1764                                args->mount_server.version = NFS_MNT3_VERSION;
1765                                break;
1766                        case 2:
1767                                args->mount_server.version = NFS_MNT_VERSION;
1768                }
1769        }
1770        request.version = args->mount_server.version;
1771
1772        if (args->mount_server.hostname)
1773                request.hostname = args->mount_server.hostname;
1774        else
1775                request.hostname = args->nfs_server.hostname;
1776
1777        /*
1778         * Construct the mount server's address.
1779         */
1780        if (args->mount_server.address.ss_family == AF_UNSPEC) {
1781                memcpy(request.sap, &args->nfs_server.address,
1782                       args->nfs_server.addrlen);
1783                args->mount_server.addrlen = args->nfs_server.addrlen;
1784        }
1785        request.salen = args->mount_server.addrlen;
1786        nfs_set_port(request.sap, &args->mount_server.port, 0);
1787
1788        /*
1789         * Now ask the mount server to map our export path
1790         * to a file handle.
1791         */
1792        status = nfs_mount(&request);
1793        if (status != 0) {
1794                dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1795                                request.hostname, status);
1796                return status;
1797        }
1798
1799        return 0;
1800}
1801
1802static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1803                                        struct nfs_subversion *nfs_mod)
1804{
1805        int status;
1806        unsigned int i;
1807        bool tried_auth_unix = false;
1808        bool auth_null_in_list = false;
1809        struct nfs_server *server = ERR_PTR(-EACCES);
1810        struct nfs_parsed_mount_data *args = mount_info->parsed;
1811        rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1812        unsigned int authlist_len = ARRAY_SIZE(authlist);
1813
1814        status = nfs_request_mount(args, mount_info->mntfh, authlist,
1815                                        &authlist_len);
1816        if (status)
1817                return ERR_PTR(status);
1818
1819        /*
1820         * Was a sec= authflavor specified in the options? First, verify
1821         * whether the server supports it, and then just try to use it if so.
1822         */
1823        if (args->auth_info.flavor_len > 0) {
1824                status = nfs_verify_authflavors(args, authlist, authlist_len);
1825                dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1826                         args->selected_flavor);
1827                if (status)
1828                        return ERR_PTR(status);
1829                return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1830        }
1831
1832        /*
1833         * No sec= option was provided. RFC 2623, section 2.7 suggests we
1834         * SHOULD prefer the flavor listed first. However, some servers list
1835         * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1836         */
1837        for (i = 0; i < authlist_len; ++i) {
1838                rpc_authflavor_t flavor;
1839                struct rpcsec_gss_info info;
1840
1841                flavor = authlist[i];
1842                switch (flavor) {
1843                case RPC_AUTH_UNIX:
1844                        tried_auth_unix = true;
1845                        break;
1846                case RPC_AUTH_NULL:
1847                        auth_null_in_list = true;
1848                        continue;
1849                default:
1850                        if (rpcauth_get_gssinfo(flavor, &info) != 0)
1851                                continue;
1852                        /* Fallthrough */
1853                }
1854                dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1855                args->selected_flavor = flavor;
1856                server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1857                if (!IS_ERR(server))
1858                        return server;
1859        }
1860
1861        /*
1862         * Nothing we tried so far worked. At this point, give up if we've
1863         * already tried AUTH_UNIX or if the server's list doesn't contain
1864         * AUTH_NULL
1865         */
1866        if (tried_auth_unix || !auth_null_in_list)
1867                return server;
1868
1869        /* Last chance! Try AUTH_UNIX */
1870        dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1871        args->selected_flavor = RPC_AUTH_UNIX;
1872        return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1873}
1874
1875struct dentry *nfs_try_mount(int flags, const char *dev_name,
1876                             struct nfs_mount_info *mount_info,
1877                             struct nfs_subversion *nfs_mod)
1878{
1879        struct nfs_server *server;
1880
1881        if (mount_info->parsed->need_mount)
1882                server = nfs_try_mount_request(mount_info, nfs_mod);
1883        else
1884                server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1885
1886        if (IS_ERR(server))
1887                return ERR_CAST(server);
1888
1889        return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1890}
1891EXPORT_SYMBOL_GPL(nfs_try_mount);
1892
1893/*
1894 * Split "dev_name" into "hostname:export_path".
1895 *
1896 * The leftmost colon demarks the split between the server's hostname
1897 * and the export path.  If the hostname starts with a left square
1898 * bracket, then it may contain colons.
1899 *
1900 * Note: caller frees hostname and export path, even on error.
1901 */
1902static int nfs_parse_devname(const char *dev_name,
1903                             char **hostname, size_t maxnamlen,
1904                             char **export_path, size_t maxpathlen)
1905{
1906        size_t len;
1907        char *end;
1908
1909        /* Is the host name protected with square brakcets? */
1910        if (*dev_name == '[') {
1911                end = strchr(++dev_name, ']');
1912                if (end == NULL || end[1] != ':')
1913                        goto out_bad_devname;
1914
1915                len = end - dev_name;
1916                end++;
1917        } else {
1918                char *comma;
1919
1920                end = strchr(dev_name, ':');
1921                if (end == NULL)
1922                        goto out_bad_devname;
1923                len = end - dev_name;
1924
1925                /* kill possible hostname list: not supported */
1926                comma = strchr(dev_name, ',');
1927                if (comma != NULL && comma < end)
1928                        *comma = 0;
1929        }
1930
1931        if (len > maxnamlen)
1932                goto out_hostname;
1933
1934        /* N.B. caller will free nfs_server.hostname in all cases */
1935        *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1936        if (*hostname == NULL)
1937                goto out_nomem;
1938        len = strlen(++end);
1939        if (len > maxpathlen)
1940                goto out_path;
1941        *export_path = kstrndup(end, len, GFP_KERNEL);
1942        if (!*export_path)
1943                goto out_nomem;
1944
1945        dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1946        return 0;
1947
1948out_bad_devname:
1949        dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1950        return -EINVAL;
1951
1952out_nomem:
1953        dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1954        return -ENOMEM;
1955
1956out_hostname:
1957        dfprintk(MOUNT, "NFS: server hostname too long\n");
1958        return -ENAMETOOLONG;
1959
1960out_path:
1961        dfprintk(MOUNT, "NFS: export pathname too long\n");
1962        return -ENAMETOOLONG;
1963}
1964
1965/*
1966 * Validate the NFS2/NFS3 mount data
1967 * - fills in the mount root filehandle
1968 *
1969 * For option strings, user space handles the following behaviors:
1970 *
1971 * + DNS: mapping server host name to IP address ("addr=" option)
1972 *
1973 * + failure mode: how to behave if a mount request can't be handled
1974 *   immediately ("fg/bg" option)
1975 *
1976 * + retry: how often to retry a mount request ("retry=" option)
1977 *
1978 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1979 *   mountproto=tcp after mountproto=udp, and so on
1980 */
1981static int nfs23_validate_mount_data(void *options,
1982                                     struct nfs_parsed_mount_data *args,
1983                                     struct nfs_fh *mntfh,
1984                                     const char *dev_name)
1985{
1986        struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1987        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1988        int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1989
1990        if (data == NULL)
1991                goto out_no_data;
1992
1993        args->version = NFS_DEFAULT_VERSION;
1994        switch (data->version) {
1995        case 1:
1996                data->namlen = 0; /* fall through */
1997        case 2:
1998                data->bsize = 0; /* fall through */
1999        case 3:
2000                if (data->flags & NFS_MOUNT_VER3)
2001                        goto out_no_v3;
2002                data->root.size = NFS2_FHSIZE;
2003                memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
2004                /* Turn off security negotiation */
2005                extra_flags |= NFS_MOUNT_SECFLAVOUR;
2006                /* fall through */
2007        case 4:
2008                if (data->flags & NFS_MOUNT_SECFLAVOUR)
2009                        goto out_no_sec;
2010                /* fall through */
2011        case 5:
2012                memset(data->context, 0, sizeof(data->context));
2013                /* fall through */
2014        case 6:
2015                if (data->flags & NFS_MOUNT_VER3) {
2016                        if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2017                                goto out_invalid_fh;
2018                        mntfh->size = data->root.size;
2019                        args->version = 3;
2020                } else {
2021                        mntfh->size = NFS2_FHSIZE;
2022                        args->version = 2;
2023                }
2024
2025
2026                memcpy(mntfh->data, data->root.data, mntfh->size);
2027                if (mntfh->size < sizeof(mntfh->data))
2028                        memset(mntfh->data + mntfh->size, 0,
2029                               sizeof(mntfh->data) - mntfh->size);
2030
2031                /*
2032                 * Translate to nfs_parsed_mount_data, which nfs_fill_super
2033                 * can deal with.
2034                 */
2035                args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2036                args->flags             |= extra_flags;
2037                args->rsize             = data->rsize;
2038                args->wsize             = data->wsize;
2039                args->timeo             = data->timeo;
2040                args->retrans           = data->retrans;
2041                args->acregmin          = data->acregmin;
2042                args->acregmax          = data->acregmax;
2043                args->acdirmin          = data->acdirmin;
2044                args->acdirmax          = data->acdirmax;
2045                args->need_mount        = false;
2046
2047                memcpy(sap, &data->addr, sizeof(data->addr));
2048                args->nfs_server.addrlen = sizeof(data->addr);
2049                args->nfs_server.port = ntohs(data->addr.sin_port);
2050                if (!nfs_verify_server_address(sap))
2051                        goto out_no_address;
2052
2053                if (!(data->flags & NFS_MOUNT_TCP))
2054                        args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2055                /* N.B. caller will free nfs_server.hostname in all cases */
2056                args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2057                args->namlen            = data->namlen;
2058                args->bsize             = data->bsize;
2059
2060                if (data->flags & NFS_MOUNT_SECFLAVOUR)
2061                        args->selected_flavor = data->pseudoflavor;
2062                else
2063                        args->selected_flavor = RPC_AUTH_UNIX;
2064                if (!args->nfs_server.hostname)
2065                        goto out_nomem;
2066
2067                if (!(data->flags & NFS_MOUNT_NONLM))
2068                        args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2069                                         NFS_MOUNT_LOCAL_FCNTL);
2070                else
2071                        args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2072                                        NFS_MOUNT_LOCAL_FCNTL);
2073                /*
2074                 * The legacy version 6 binary mount data from userspace has a
2075                 * field used only to transport selinux information into the
2076                 * the kernel.  To continue to support that functionality we
2077                 * have a touch of selinux knowledge here in the NFS code. The
2078                 * userspace code converted context=blah to just blah so we are
2079                 * converting back to the full string selinux understands.
2080                 */
2081                if (data->context[0]){
2082#ifdef CONFIG_SECURITY_SELINUX
2083                        int rc;
2084                        char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2085                        if (!opts_str)
2086                                return -ENOMEM;
2087                        strcpy(opts_str, "context=");
2088                        data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2089                        strcat(opts_str, &data->context[0]);
2090                        rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2091                        kfree(opts_str);
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
2106out_no_data:
2107        dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2108        return -EINVAL;
2109
2110out_no_v3:
2111        dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2112                 data->version);
2113        return -EINVAL;
2114
2115out_no_sec:
2116        dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2117        return -EINVAL;
2118
2119out_nomem:
2120        dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2121        return -ENOMEM;
2122
2123out_no_address:
2124        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2125        return -EINVAL;
2126
2127out_invalid_fh:
2128        dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2129        return -EINVAL;
2130}
2131
2132#if IS_ENABLED(CONFIG_NFS_V4)
2133static 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
2144static 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
2154static 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                port = NFS_PORT;
2172                max_namelen = NFS4_MAXNAMLEN;
2173                max_pathlen = NFS4_MAXPATHLEN;
2174                nfs_validate_transport_protocol(args);
2175                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2176                        goto out_invalid_transport_udp;
2177                nfs4_validate_mount_flags(args);
2178#else
2179                goto out_v4_not_compiled;
2180#endif /* CONFIG_NFS_V4 */
2181        } else
2182                nfs_set_mount_transport_protocol(args);
2183
2184        nfs_set_port(sap, &args->nfs_server.port, port);
2185
2186        return nfs_parse_devname(dev_name,
2187                                   &args->nfs_server.hostname,
2188                                   max_namelen,
2189                                   &args->nfs_server.export_path,
2190                                   max_pathlen);
2191
2192#if !IS_ENABLED(CONFIG_NFS_V4)
2193out_v4_not_compiled:
2194        dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2195        return -EPROTONOSUPPORT;
2196#else
2197out_invalid_transport_udp:
2198        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2199        return -EINVAL;
2200#endif /* !CONFIG_NFS_V4 */
2201
2202out_no_address:
2203        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2204        return -EINVAL;
2205}
2206
2207#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2208                | NFS_MOUNT_SECURE \
2209                | NFS_MOUNT_TCP \
2210                | NFS_MOUNT_VER3 \
2211                | NFS_MOUNT_KERBEROS \
2212                | NFS_MOUNT_NONLM \
2213                | NFS_MOUNT_BROKEN_SUID \
2214                | NFS_MOUNT_STRICTLOCK \
2215                | NFS_MOUNT_LEGACY_INTERFACE)
2216
2217#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2218                ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2219
2220static int
2221nfs_compare_remount_data(struct nfs_server *nfss,
2222                         struct nfs_parsed_mount_data *data)
2223{
2224        if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2225            data->rsize != nfss->rsize ||
2226            data->wsize != nfss->wsize ||
2227            data->version != nfss->nfs_client->rpc_ops->version ||
2228            data->minorversion != nfss->nfs_client->cl_minorversion ||
2229            data->retrans != nfss->client->cl_timeout->to_retries ||
2230            !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2231            data->acregmin != nfss->acregmin / HZ ||
2232            data->acregmax != nfss->acregmax / HZ ||
2233            data->acdirmin != nfss->acdirmin / HZ ||
2234            data->acdirmax != nfss->acdirmax / HZ ||
2235            data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2236            data->nfs_server.port != nfss->port ||
2237            data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2238            !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2239                          (struct sockaddr *)&nfss->nfs_client->cl_addr))
2240                return -EINVAL;
2241
2242        return 0;
2243}
2244
2245int
2246nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2247{
2248        int error;
2249        struct nfs_server *nfss = sb->s_fs_info;
2250        struct nfs_parsed_mount_data *data;
2251        struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2252        struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2253        u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2254
2255        sync_filesystem(sb);
2256
2257        /*
2258         * Userspace mount programs that send binary options generally send
2259         * them populated with default values. We have no way to know which
2260         * ones were explicitly specified. Fall back to legacy behavior and
2261         * just return success.
2262         */
2263        if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2264            (nfsvers <= 3 && (!options || (options->version >= 1 &&
2265                                           options->version <= 6))))
2266                return 0;
2267
2268        data = kzalloc(sizeof(*data), GFP_KERNEL);
2269        if (data == NULL)
2270                return -ENOMEM;
2271
2272        /* fill out struct with values from existing mount */
2273        data->flags = nfss->flags;
2274        data->rsize = nfss->rsize;
2275        data->wsize = nfss->wsize;
2276        data->retrans = nfss->client->cl_timeout->to_retries;
2277        data->selected_flavor = nfss->client->cl_auth->au_flavor;
2278        data->acregmin = nfss->acregmin / HZ;
2279        data->acregmax = nfss->acregmax / HZ;
2280        data->acdirmin = nfss->acdirmin / HZ;
2281        data->acdirmax = nfss->acdirmax / HZ;
2282        data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2283        data->nfs_server.port = nfss->port;
2284        data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2285        data->version = nfsvers;
2286        data->minorversion = nfss->nfs_client->cl_minorversion;
2287        data->net = current->nsproxy->net_ns;
2288        memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2289                data->nfs_server.addrlen);
2290
2291        /* overwrite those values with any that were specified */
2292        error = -EINVAL;
2293        if (!nfs_parse_mount_options((char *)options, data))
2294                goto out;
2295
2296        /*
2297         * noac is a special case. It implies -o sync, but that's not
2298         * necessarily reflected in the mtab options. do_remount_sb
2299         * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
2300         * remount options, so we have to explicitly reset it.
2301         */
2302        if (data->flags & NFS_MOUNT_NOAC)
2303                *flags |= SB_SYNCHRONOUS;
2304
2305        /* compare new mount options with old ones */
2306        error = nfs_compare_remount_data(nfss, data);
2307out:
2308        kfree(data);
2309        return error;
2310}
2311EXPORT_SYMBOL_GPL(nfs_remount);
2312
2313/*
2314 * Initialise the common bits of the superblock
2315 */
2316static void nfs_initialise_sb(struct super_block *sb)
2317{
2318        struct nfs_server *server = NFS_SB(sb);
2319
2320        sb->s_magic = NFS_SUPER_MAGIC;
2321
2322        /* We probably want something more informative here */
2323        snprintf(sb->s_id, sizeof(sb->s_id),
2324                 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2325
2326        if (sb->s_blocksize == 0)
2327                sb->s_blocksize = nfs_block_bits(server->wsize,
2328                                                 &sb->s_blocksize_bits);
2329
2330        nfs_super_set_maxbytes(sb, server->maxfilesize);
2331}
2332
2333/*
2334 * Finish setting up an NFS2/3 superblock
2335 */
2336void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2337{
2338        struct nfs_parsed_mount_data *data = mount_info->parsed;
2339        struct nfs_server *server = NFS_SB(sb);
2340
2341        sb->s_blocksize_bits = 0;
2342        sb->s_blocksize = 0;
2343        sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2344        sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2345        if (data && data->bsize)
2346                sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2347
2348        if (server->nfs_client->rpc_ops->version != 2) {
2349                /* The VFS shouldn't apply the umask to mode bits. We will do
2350                 * so ourselves when necessary.
2351                 */
2352                sb->s_flags |= SB_POSIXACL;
2353                sb->s_time_gran = 1;
2354                sb->s_export_op = &nfs_export_ops;
2355        }
2356
2357        nfs_initialise_sb(sb);
2358}
2359EXPORT_SYMBOL_GPL(nfs_fill_super);
2360
2361/*
2362 * Finish setting up a cloned NFS2/3/4 superblock
2363 */
2364static void nfs_clone_super(struct super_block *sb,
2365                            struct nfs_mount_info *mount_info)
2366{
2367        const struct super_block *old_sb = mount_info->cloned->sb;
2368        struct nfs_server *server = NFS_SB(sb);
2369
2370        sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2371        sb->s_blocksize = old_sb->s_blocksize;
2372        sb->s_maxbytes = old_sb->s_maxbytes;
2373        sb->s_xattr = old_sb->s_xattr;
2374        sb->s_op = old_sb->s_op;
2375        sb->s_time_gran = 1;
2376        sb->s_export_op = old_sb->s_export_op;
2377
2378        if (server->nfs_client->rpc_ops->version != 2) {
2379                /* The VFS shouldn't apply the umask to mode bits. We will do
2380                 * so ourselves when necessary.
2381                 */
2382                sb->s_flags |= SB_POSIXACL;
2383        }
2384
2385        nfs_initialise_sb(sb);
2386}
2387
2388static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2389{
2390        const struct nfs_server *a = s->s_fs_info;
2391        const struct rpc_clnt *clnt_a = a->client;
2392        const struct rpc_clnt *clnt_b = b->client;
2393
2394        if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2395                goto Ebusy;
2396        if (a->nfs_client != b->nfs_client)
2397                goto Ebusy;
2398        if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2399                goto Ebusy;
2400        if (a->wsize != b->wsize)
2401                goto Ebusy;
2402        if (a->rsize != b->rsize)
2403                goto Ebusy;
2404        if (a->acregmin != b->acregmin)
2405                goto Ebusy;
2406        if (a->acregmax != b->acregmax)
2407                goto Ebusy;
2408        if (a->acdirmin != b->acdirmin)
2409                goto Ebusy;
2410        if (a->acdirmax != b->acdirmax)
2411                goto Ebusy;
2412        if (b->auth_info.flavor_len > 0 &&
2413           clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2414                goto Ebusy;
2415        return 1;
2416Ebusy:
2417        return 0;
2418}
2419
2420struct nfs_sb_mountdata {
2421        struct nfs_server *server;
2422        int mntflags;
2423};
2424
2425static int nfs_set_super(struct super_block *s, void *data)
2426{
2427        struct nfs_sb_mountdata *sb_mntdata = data;
2428        struct nfs_server *server = sb_mntdata->server;
2429        int ret;
2430
2431        s->s_flags = sb_mntdata->mntflags;
2432        s->s_fs_info = server;
2433        s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2434        ret = set_anon_super(s, server);
2435        if (ret == 0)
2436                server->s_dev = s->s_dev;
2437        return ret;
2438}
2439
2440static int nfs_compare_super_address(struct nfs_server *server1,
2441                                     struct nfs_server *server2)
2442{
2443        struct sockaddr *sap1, *sap2;
2444        struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2445        struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2446
2447        if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2448                return 0;
2449
2450        sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2451        sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2452
2453        if (sap1->sa_family != sap2->sa_family)
2454                return 0;
2455
2456        switch (sap1->sa_family) {
2457        case AF_INET: {
2458                struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2459                struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2460                if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2461                        return 0;
2462                if (sin1->sin_port != sin2->sin_port)
2463                        return 0;
2464                break;
2465        }
2466        case AF_INET6: {
2467                struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2468                struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2469                if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2470                        return 0;
2471                if (sin1->sin6_port != sin2->sin6_port)
2472                        return 0;
2473                break;
2474        }
2475        default:
2476                return 0;
2477        }
2478
2479        return 1;
2480}
2481
2482static int nfs_compare_super(struct super_block *sb, void *data)
2483{
2484        struct nfs_sb_mountdata *sb_mntdata = data;
2485        struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2486        int mntflags = sb_mntdata->mntflags;
2487
2488        if (!nfs_compare_super_address(old, server))
2489                return 0;
2490        /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2491        if (old->flags & NFS_MOUNT_UNSHARED)
2492                return 0;
2493        if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2494                return 0;
2495        return nfs_compare_mount_options(sb, server, mntflags);
2496}
2497
2498#ifdef CONFIG_NFS_FSCACHE
2499static void nfs_get_cache_cookie(struct super_block *sb,
2500                                 struct nfs_parsed_mount_data *parsed,
2501                                 struct nfs_clone_mount *cloned)
2502{
2503        struct nfs_server *nfss = NFS_SB(sb);
2504        char *uniq = NULL;
2505        int ulen = 0;
2506
2507        nfss->fscache_key = NULL;
2508        nfss->fscache = NULL;
2509
2510        if (parsed) {
2511                if (!(parsed->options & NFS_OPTION_FSCACHE))
2512                        return;
2513                if (parsed->fscache_uniq) {
2514                        uniq = parsed->fscache_uniq;
2515                        ulen = strlen(parsed->fscache_uniq);
2516                }
2517        } else if (cloned) {
2518                struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2519                if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2520                        return;
2521                if (mnt_s->fscache_key) {
2522                        uniq = mnt_s->fscache_key->key.uniquifier;
2523                        ulen = mnt_s->fscache_key->key.uniq_len;
2524                };
2525        } else
2526                return;
2527
2528        nfs_fscache_get_super_cookie(sb, uniq, ulen);
2529}
2530#else
2531static void nfs_get_cache_cookie(struct super_block *sb,
2532                                 struct nfs_parsed_mount_data *parsed,
2533                                 struct nfs_clone_mount *cloned)
2534{
2535}
2536#endif
2537
2538int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2539                        struct nfs_mount_info *mount_info)
2540{
2541        int error;
2542        unsigned long kflags = 0, kflags_out = 0;
2543        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2544                kflags |= SECURITY_LSM_NATIVE_LABELS;
2545
2546        error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2547                                                kflags, &kflags_out);
2548        if (error)
2549                goto err;
2550
2551        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2552                !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2553                NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2554err:
2555        return error;
2556}
2557EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2558
2559int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2560                          struct nfs_mount_info *mount_info)
2561{
2562        int error;
2563        unsigned long kflags = 0, kflags_out = 0;
2564
2565        /* clone any lsm security options from the parent to the new sb */
2566        if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2567                return -ESTALE;
2568
2569        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2570                kflags |= SECURITY_LSM_NATIVE_LABELS;
2571
2572        error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
2573                        &kflags_out);
2574        if (error)
2575                return error;
2576
2577        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2578                !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2579                NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2580        return 0;
2581}
2582EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2583
2584struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2585                                   int flags, const char *dev_name,
2586                                   struct nfs_mount_info *mount_info,
2587                                   struct nfs_subversion *nfs_mod)
2588{
2589        struct super_block *s;
2590        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2591        int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2592        struct nfs_sb_mountdata sb_mntdata = {
2593                .mntflags = flags,
2594                .server = server,
2595        };
2596        int error;
2597
2598        if (server->flags & NFS_MOUNT_UNSHARED)
2599                compare_super = NULL;
2600
2601        /* -o noac implies -o sync */
2602        if (server->flags & NFS_MOUNT_NOAC)
2603                sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2604
2605        if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2606                if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
2607                        sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2608
2609        /* Get a superblock - note that we may end up sharing one that already exists */
2610        s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2611        if (IS_ERR(s)) {
2612                mntroot = ERR_CAST(s);
2613                goto out_err_nosb;
2614        }
2615
2616        if (s->s_fs_info != server) {
2617                nfs_free_server(server);
2618                server = NULL;
2619        } else {
2620                error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
2621                                             MINOR(server->s_dev));
2622                if (error) {
2623                        mntroot = ERR_PTR(error);
2624                        goto error_splat_super;
2625                }
2626                s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
2627                server->super = s;
2628        }
2629
2630        if (!s->s_root) {
2631                /* initial superblock/root creation */
2632                mount_info->fill_super(s, mount_info);
2633                nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2634                if (!(server->flags & NFS_MOUNT_UNSHARED))
2635                        s->s_iflags |= SB_I_MULTIROOT;
2636        }
2637
2638        mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2639        if (IS_ERR(mntroot))
2640                goto error_splat_super;
2641
2642        error = mount_info->set_security(s, mntroot, mount_info);
2643        if (error)
2644                goto error_splat_root;
2645
2646        s->s_flags |= SB_ACTIVE;
2647
2648out:
2649        return mntroot;
2650
2651out_err_nosb:
2652        nfs_free_server(server);
2653        goto out;
2654
2655error_splat_root:
2656        dput(mntroot);
2657        mntroot = ERR_PTR(error);
2658error_splat_super:
2659        deactivate_locked_super(s);
2660        goto out;
2661}
2662EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2663
2664struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2665        int flags, const char *dev_name, void *raw_data)
2666{
2667        struct nfs_mount_info mount_info = {
2668                .fill_super = nfs_fill_super,
2669                .set_security = nfs_set_sb_security,
2670        };
2671        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2672        struct nfs_subversion *nfs_mod;
2673        int error;
2674
2675        mount_info.parsed = nfs_alloc_parsed_mount_data();
2676        mount_info.mntfh = nfs_alloc_fhandle();
2677        if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2678                goto out;
2679
2680        /* Validate the mount data */
2681        error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2682        if (error == NFS_TEXT_DATA)
2683                error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2684        if (error < 0) {
2685                mntroot = ERR_PTR(error);
2686                goto out;
2687        }
2688
2689        nfs_mod = get_nfs_version(mount_info.parsed->version);
2690        if (IS_ERR(nfs_mod)) {
2691                mntroot = ERR_CAST(nfs_mod);
2692                goto out;
2693        }
2694
2695        mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2696
2697        put_nfs_version(nfs_mod);
2698out:
2699        nfs_free_parsed_mount_data(mount_info.parsed);
2700        nfs_free_fhandle(mount_info.mntfh);
2701        return mntroot;
2702}
2703EXPORT_SYMBOL_GPL(nfs_fs_mount);
2704
2705/*
2706 * Destroy an NFS2/3 superblock
2707 */
2708void nfs_kill_super(struct super_block *s)
2709{
2710        struct nfs_server *server = NFS_SB(s);
2711        dev_t dev = s->s_dev;
2712
2713        generic_shutdown_super(s);
2714
2715        nfs_fscache_release_super_cookie(s);
2716
2717        nfs_free_server(server);
2718        free_anon_bdev(dev);
2719}
2720EXPORT_SYMBOL_GPL(nfs_kill_super);
2721
2722/*
2723 * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2724 */
2725static struct dentry *
2726nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2727                const char *dev_name, void *raw_data)
2728{
2729        struct nfs_clone_mount *data = raw_data;
2730        struct nfs_mount_info mount_info = {
2731                .fill_super = nfs_clone_super,
2732                .set_security = nfs_clone_sb_security,
2733                .cloned = data,
2734        };
2735        struct nfs_server *server;
2736        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2737        struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2738
2739        dprintk("--> nfs_xdev_mount()\n");
2740
2741        mount_info.mntfh = mount_info.cloned->fh;
2742
2743        /* create a new volume representation */
2744        server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2745
2746        if (IS_ERR(server))
2747                mntroot = ERR_CAST(server);
2748        else
2749                mntroot = nfs_fs_mount_common(server, flags,
2750                                dev_name, &mount_info, nfs_mod);
2751
2752        dprintk("<-- nfs_xdev_mount() = %ld\n",
2753                        IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2754        return mntroot;
2755}
2756
2757#if IS_ENABLED(CONFIG_NFS_V4)
2758
2759static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2760{
2761        args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2762                         NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2763}
2764
2765/*
2766 * Validate NFSv4 mount options
2767 */
2768static int nfs4_validate_mount_data(void *options,
2769                                    struct nfs_parsed_mount_data *args,
2770                                    const char *dev_name)
2771{
2772        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2773        struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2774        char *c;
2775
2776        if (data == NULL)
2777                goto out_no_data;
2778
2779        args->version = 4;
2780
2781        switch (data->version) {
2782        case 1:
2783                if (data->host_addrlen > sizeof(args->nfs_server.address))
2784                        goto out_no_address;
2785                if (data->host_addrlen == 0)
2786                        goto out_no_address;
2787                args->nfs_server.addrlen = data->host_addrlen;
2788                if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2789                        return -EFAULT;
2790                if (!nfs_verify_server_address(sap))
2791                        goto out_no_address;
2792                args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2793
2794                if (data->auth_flavourlen) {
2795                        rpc_authflavor_t pseudoflavor;
2796                        if (data->auth_flavourlen > 1)
2797                                goto out_inval_auth;
2798                        if (copy_from_user(&pseudoflavor,
2799                                           data->auth_flavours,
2800                                           sizeof(pseudoflavor)))
2801                                return -EFAULT;
2802                        args->selected_flavor = pseudoflavor;
2803                } else
2804                        args->selected_flavor = RPC_AUTH_UNIX;
2805
2806                c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2807                if (IS_ERR(c))
2808                        return PTR_ERR(c);
2809                args->nfs_server.hostname = c;
2810
2811                c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2812                if (IS_ERR(c))
2813                        return PTR_ERR(c);
2814                args->nfs_server.export_path = c;
2815                dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2816
2817                c = strndup_user(data->client_addr.data, 16);
2818                if (IS_ERR(c))
2819                        return PTR_ERR(c);
2820                args->client_address = c;
2821
2822                /*
2823                 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2824                 * can deal with.
2825                 */
2826
2827                args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2828                args->rsize     = data->rsize;
2829                args->wsize     = data->wsize;
2830                args->timeo     = data->timeo;
2831                args->retrans   = data->retrans;
2832                args->acregmin  = data->acregmin;
2833                args->acregmax  = data->acregmax;
2834                args->acdirmin  = data->acdirmin;
2835                args->acdirmax  = data->acdirmax;
2836                args->nfs_server.protocol = data->proto;
2837                nfs_validate_transport_protocol(args);
2838                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2839                        goto out_invalid_transport_udp;
2840
2841                break;
2842        default:
2843                return NFS_TEXT_DATA;
2844        }
2845
2846        return 0;
2847
2848out_no_data:
2849        dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2850        return -EINVAL;
2851
2852out_inval_auth:
2853        dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2854                 data->auth_flavourlen);
2855        return -EINVAL;
2856
2857out_no_address:
2858        dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2859        return -EINVAL;
2860
2861out_invalid_transport_udp:
2862        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2863        return -EINVAL;
2864}
2865
2866/*
2867 * NFS v4 module parameters need to stay in the
2868 * NFS client for backwards compatibility
2869 */
2870unsigned int nfs_callback_set_tcpport;
2871unsigned short nfs_callback_nr_threads;
2872/* Default cache timeout is 10 minutes */
2873unsigned int nfs_idmap_cache_timeout = 600;
2874/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2875bool nfs4_disable_idmapping = true;
2876unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2877unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
2878unsigned short send_implementation_id = 1;
2879char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2880bool recover_lost_locks = false;
2881
2882EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
2883EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2884EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2885EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2886EXPORT_SYMBOL_GPL(max_session_slots);
2887EXPORT_SYMBOL_GPL(max_session_cb_slots);
2888EXPORT_SYMBOL_GPL(send_implementation_id);
2889EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2890EXPORT_SYMBOL_GPL(recover_lost_locks);
2891
2892#define NFS_CALLBACK_MAXPORTNR (65535U)
2893
2894static int param_set_portnr(const char *val, const struct kernel_param *kp)
2895{
2896        unsigned long num;
2897        int ret;
2898
2899        if (!val)
2900                return -EINVAL;
2901        ret = kstrtoul(val, 0, &num);
2902        if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2903                return -EINVAL;
2904        *((unsigned int *)kp->arg) = num;
2905        return 0;
2906}
2907static const struct kernel_param_ops param_ops_portnr = {
2908        .set = param_set_portnr,
2909        .get = param_get_uint,
2910};
2911#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2912
2913module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2914module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
2915MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
2916                "assigned to the NFSv4 callback channels.");
2917module_param(nfs_idmap_cache_timeout, int, 0644);
2918module_param(nfs4_disable_idmapping, bool, 0644);
2919module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2920                        NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2921MODULE_PARM_DESC(nfs4_disable_idmapping,
2922                "Turn off NFSv4 idmapping when using 'sec=sys'");
2923module_param(max_session_slots, ushort, 0644);
2924MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2925                "requests the client will negotiate");
2926module_param(max_session_cb_slots, ushort, 0644);
2927MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
2928                "callbacks the client will process for a given server");
2929module_param(send_implementation_id, ushort, 0644);
2930MODULE_PARM_DESC(send_implementation_id,
2931                "Send implementation ID with NFSv4.1 exchange_id");
2932MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2933
2934module_param(recover_lost_locks, bool, 0644);
2935MODULE_PARM_DESC(recover_lost_locks,
2936                 "If the server reports that a lock might be lost, "
2937                 "try to recover it risking data corruption.");
2938
2939
2940#endif /* CONFIG_NFS_V4 */
2941