fs/nfs/fs_context.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/fs/nfs/fs_context.c
   4  *
   5  * Copyright (C) 1992 Rick Sladkey
   6  * Conversion to new mount api Copyright (C) David Howells
   7  *
   8  * NFS mount handling.
   9  *
  10  * Split from fs/nfs/super.c by David Howells <dhowells@redhat.com>
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/fs.h>
  15 #include <linux/fs_context.h>
  16 #include <linux/fs_parser.h>
  17 #include <linux/nfs_fs.h>
  18 #include <linux/nfs_mount.h>
  19 #include <linux/nfs4_mount.h>
  20 #include "nfs.h"
  21 #include "internal.h"
  22
  23 #define NFSDBG_FACILITY         NFSDBG_MOUNT
  24
  25 #if IS_ENABLED(CONFIG_NFS_V3)
  26 #define NFS_DEFAULT_VERSION 3
  27 #else
  28 #define NFS_DEFAULT_VERSION 2
  29 #endif
  30
  31 #define NFS_MAX_CONNECTIONS 16
  32
  33 enum nfs_param {
  34         Opt_ac,
  35         Opt_acdirmax,
  36         Opt_acdirmin,
  37         Opt_acl,
  38         Opt_acregmax,
  39         Opt_acregmin,
  40         Opt_actimeo,
  41         Opt_addr,
  42         Opt_bg,
  43         Opt_bsize,
  44         Opt_clientaddr,
  45         Opt_cto,
  46         Opt_fg,
  47         Opt_fscache,
  48         Opt_fscache_flag,
  49         Opt_hard,
  50         Opt_intr,
  51         Opt_local_lock,
  52         Opt_lock,
  53         Opt_lookupcache,
  54         Opt_migration,
  55         Opt_minorversion,
  56         Opt_mountaddr,
  57         Opt_mounthost,
  58         Opt_mountport,
  59         Opt_mountproto,
  60         Opt_mountvers,
  61         Opt_namelen,
  62         Opt_nconnect,
  63         Opt_port,
  64         Opt_posix,
  65         Opt_proto,
  66         Opt_rdirplus,
  67         Opt_rdma,
  68         Opt_resvport,
  69         Opt_retrans,
  70         Opt_retry,
  71         Opt_rsize,
  72         Opt_sec,
  73         Opt_sharecache,
  74         Opt_sloppy,
  75         Opt_soft,
  76         Opt_softerr,
  77         Opt_softreval,
  78         Opt_source,
  79         Opt_tcp,
  80         Opt_timeo,
  81         Opt_udp,
  82         Opt_v,
  83         Opt_vers,
  84         Opt_wsize,
  85         Opt_write,
  86 };
  87
  88 enum {
  89         Opt_local_lock_all,
  90         Opt_local_lock_flock,
  91         Opt_local_lock_none,
  92         Opt_local_lock_posix,
  93 };
  94
  95 static const struct constant_table nfs_param_enums_local_lock[] = {
  96         { "all",                Opt_local_lock_all },
  97         { "flock",      Opt_local_lock_flock },
  98         { "posix",      Opt_local_lock_posix },
  99         { "none",               Opt_local_lock_none },
 100         {}
 101 };
 102
 103 enum {
 104         Opt_lookupcache_all,
 105         Opt_lookupcache_none,
 106         Opt_lookupcache_positive,
 107 };
 108
 109 static const struct constant_table nfs_param_enums_lookupcache[] = {
 110         { "all",                Opt_lookupcache_all },
 111         { "none",               Opt_lookupcache_none },
 112         { "pos",                Opt_lookupcache_positive },
 113         { "positive",           Opt_lookupcache_positive },
 114         {}
 115 };
 116
 117 enum {
 118         Opt_write_lazy,
 119         Opt_write_eager,
 120         Opt_write_wait,
 121 };
 122
 123 static const struct constant_table nfs_param_enums_write[] = {
 124         { "lazy",               Opt_write_lazy },
 125         { "eager",              Opt_write_eager },
 126         { "wait",               Opt_write_wait },
 127         {}
 128 };
 129
 130 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 131         fsparam_flag_no("ac",           Opt_ac),
 132         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 133         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 134         fsparam_flag_no("acl",          Opt_acl),
 135         fsparam_u32   ("acregmax",      Opt_acregmax),
 136         fsparam_u32   ("acregmin",      Opt_acregmin),
 137         fsparam_u32   ("actimeo",       Opt_actimeo),
 138         fsparam_string("addr",          Opt_addr),
 139         fsparam_flag  ("bg",            Opt_bg),
 140         fsparam_u32   ("bsize",         Opt_bsize),
 141         fsparam_string("clientaddr",    Opt_clientaddr),
 142         fsparam_flag_no("cto",          Opt_cto),
 143         fsparam_flag  ("fg",            Opt_fg),
 144         fsparam_flag_no("fsc",          Opt_fscache_flag),
 145         fsparam_string("fsc",           Opt_fscache),
 146         fsparam_flag  ("hard",          Opt_hard),
 147         __fsparam(NULL, "intr",         Opt_intr,
 148                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 149         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 150         fsparam_flag_no("lock",         Opt_lock),
 151         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 152         fsparam_flag_no("migration",    Opt_migration),
 153         fsparam_u32   ("minorversion",  Opt_minorversion),
 154         fsparam_string("mountaddr",     Opt_mountaddr),
 155         fsparam_string("mounthost",     Opt_mounthost),
 156         fsparam_u32   ("mountport",     Opt_mountport),
 157         fsparam_string("mountproto",    Opt_mountproto),
 158         fsparam_u32   ("mountvers",     Opt_mountvers),
 159         fsparam_u32   ("namlen",        Opt_namelen),
 160         fsparam_u32   ("nconnect",      Opt_nconnect),
 161         fsparam_string("nfsvers",       Opt_vers),
 162         fsparam_u32   ("port",          Opt_port),
 163         fsparam_flag_no("posix",        Opt_posix),
 164         fsparam_string("proto",         Opt_proto),
 165         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 166         fsparam_flag  ("rdma",          Opt_rdma),
 167         fsparam_flag_no("resvport",     Opt_resvport),
 168         fsparam_u32   ("retrans",       Opt_retrans),
 169         fsparam_string("retry",         Opt_retry),
 170         fsparam_u32   ("rsize",         Opt_rsize),
 171         fsparam_string("sec",           Opt_sec),
 172         fsparam_flag_no("sharecache",   Opt_sharecache),
 173         fsparam_flag  ("sloppy",        Opt_sloppy),
 174         fsparam_flag  ("soft",          Opt_soft),
 175         fsparam_flag  ("softerr",       Opt_softerr),
 176         fsparam_flag  ("softreval",     Opt_softreval),
 177         fsparam_string("source",        Opt_source),
 178         fsparam_flag  ("tcp",           Opt_tcp),
 179         fsparam_u32   ("timeo",         Opt_timeo),
 180         fsparam_flag  ("udp",           Opt_udp),
 181         fsparam_flag  ("v2",            Opt_v),
 182         fsparam_flag  ("v3",            Opt_v),
 183         fsparam_flag  ("v4",            Opt_v),
 184         fsparam_flag  ("v4.0",          Opt_v),
 185         fsparam_flag  ("v4.1",          Opt_v),
 186         fsparam_flag  ("v4.2",          Opt_v),
 187         fsparam_string("vers",          Opt_vers),
 188         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 189         fsparam_u32   ("wsize",         Opt_wsize),
 190         {}
 191 };
 192
 193 enum {
 194         Opt_vers_2,
 195         Opt_vers_3,
 196         Opt_vers_4,
 197         Opt_vers_4_0,
 198         Opt_vers_4_1,
 199         Opt_vers_4_2,
 200 };
 201
 202 static const struct constant_table nfs_vers_tokens[] = {
 203         { "2",          Opt_vers_2 },
 204         { "3",          Opt_vers_3 },
 205         { "4",          Opt_vers_4 },
 206         { "4.0",        Opt_vers_4_0 },
 207         { "4.1",        Opt_vers_4_1 },
 208         { "4.2",        Opt_vers_4_2 },
 209         {}
 210 };
 211
 212 enum {
 213         Opt_xprt_rdma,
 214         Opt_xprt_rdma6,
 215         Opt_xprt_tcp,
 216         Opt_xprt_tcp6,
 217         Opt_xprt_udp,
 218         Opt_xprt_udp6,
 219         nr__Opt_xprt
 220 };
 221
 222 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 223         { "rdma",       Opt_xprt_rdma },
 224         { "rdma6",      Opt_xprt_rdma6 },
 225         { "tcp",        Opt_xprt_tcp },
 226         { "tcp6",       Opt_xprt_tcp6 },
 227         { "udp",        Opt_xprt_udp },
 228         { "udp6",       Opt_xprt_udp6 },
 229         {}
 230 };
 231
 232 enum {
 233         Opt_sec_krb5,
 234         Opt_sec_krb5i,
 235         Opt_sec_krb5p,
 236         Opt_sec_lkey,
 237         Opt_sec_lkeyi,
 238         Opt_sec_lkeyp,
 239         Opt_sec_none,
 240         Opt_sec_spkm,
 241         Opt_sec_spkmi,
 242         Opt_sec_spkmp,
 243         Opt_sec_sys,
 244         nr__Opt_sec
 245 };
 246
 247 static const struct constant_table nfs_secflavor_tokens[] = {
 248         { "krb5",       Opt_sec_krb5 },
 249         { "krb5i",      Opt_sec_krb5i },
 250         { "krb5p",      Opt_sec_krb5p },
 251         { "lkey",       Opt_sec_lkey },
 252         { "lkeyi",      Opt_sec_lkeyi },
 253         { "lkeyp",      Opt_sec_lkeyp },
 254         { "none",       Opt_sec_none },
 255         { "null",       Opt_sec_none },
 256         { "spkm3",      Opt_sec_spkm },
 257         { "spkm3i",     Opt_sec_spkmi },
 258         { "spkm3p",     Opt_sec_spkmp },
 259         { "sys",        Opt_sec_sys },
 260         {}
 261 };
 262
 263 /*
 264  * Sanity-check a server address provided by the mount command.
 265  *
 266  * Address family must be initialized, and address must not be
 267  * the ANY address for that family.
 268  */
 269 static int nfs_verify_server_address(struct sockaddr *addr)
 270 {
 271         switch (addr->sa_family) {
 272         case AF_INET: {
 273                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 274                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 275         }
 276         case AF_INET6: {
 277                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 278                 return !ipv6_addr_any(sa);
 279         }
 280         }
 281
 282         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 283         return 0;
 284 }
 285
 286 /*
 287  * Sanity check the NFS transport protocol.
 288  *
 289  */
 290 static void nfs_validate_transport_protocol(struct nfs_fs_context *ctx)
 291 {
 292         switch (ctx->nfs_server.protocol) {
 293         case XPRT_TRANSPORT_UDP:
 294         case XPRT_TRANSPORT_TCP:
 295         case XPRT_TRANSPORT_RDMA:
 296                 break;
 297         default:
 298                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 299         }
 300 }
 301
 302 /*
 303  * For text based NFSv2/v3 mounts, the mount protocol transport default
 304  * settings should depend upon the specified NFS transport.
 305  */
 306 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 307 {
 308         nfs_validate_transport_protocol(ctx);
 309
 310         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 311             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 312                         return;
 313         switch (ctx->nfs_server.protocol) {
 314         case XPRT_TRANSPORT_UDP:
 315                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 316                 break;
 317         case XPRT_TRANSPORT_TCP:
 318         case XPRT_TRANSPORT_RDMA:
 319                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 320         }
 321 }
 322
 323 /*
 324  * Add 'flavor' to 'auth_info' if not already present.
 325  * Returns true if 'flavor' ends up in the list, false otherwise
 326  */
 327 static int nfs_auth_info_add(struct fs_context *fc,
 328                              struct nfs_auth_info *auth_info,
 329                              rpc_authflavor_t flavor)
 330 {
 331         unsigned int i;
 332         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 333
 334         /* make sure this flavor isn't already in the list */
 335         for (i = 0; i < auth_info->flavor_len; i++) {
 336                 if (flavor == auth_info->flavors[i])
 337                         return 0;
 338         }
 339
 340         if (auth_info->flavor_len + 1 >= max_flavor_len)
 341                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 342
 343         auth_info->flavors[auth_info->flavor_len++] = flavor;
 344         return 0;
 345 }
 346
 347 /*
 348  * Parse the value of the 'sec=' option.
 349  */
 350 static int nfs_parse_security_flavors(struct fs_context *fc,
 351                                       struct fs_parameter *param)
 352 {
 353         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 354         rpc_authflavor_t pseudoflavor;
 355         char *string = param->string, *p;
 356         int ret;
 357
 358         dfprintk(MOUNT, "NFS: parsing %s=%s option\n", param->key, param->string);
 359
 360         while ((p = strsep(&string, ":")) != NULL) {
 361                 if (!*p)
 362                         continue;
 363                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 364                 case Opt_sec_none:
 365                         pseudoflavor = RPC_AUTH_NULL;
 366                         break;
 367                 case Opt_sec_sys:
 368                         pseudoflavor = RPC_AUTH_UNIX;
 369                         break;
 370                 case Opt_sec_krb5:
 371                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 372                         break;
 373                 case Opt_sec_krb5i:
 374                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 375                         break;
 376                 case Opt_sec_krb5p:
 377                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 378                         break;
 379                 case Opt_sec_lkey:
 380                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 381                         break;
 382                 case Opt_sec_lkeyi:
 383                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 384                         break;
 385                 case Opt_sec_lkeyp:
 386                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 387                         break;
 388                 case Opt_sec_spkm:
 389                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 390                         break;
 391                 case Opt_sec_spkmi:
 392                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 393                         break;
 394                 case Opt_sec_spkmp:
 395                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 396                         break;
 397                 default:
 398                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 399                 }
 400
 401                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 402                 if (ret < 0)
 403                         return ret;
 404         }
 405
 406         return 0;
 407 }
 408
 409 static int nfs_parse_version_string(struct fs_context *fc,
 410                                     const char *string)
 411 {
 412         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 413
 414         ctx->flags &= ~NFS_MOUNT_VER3;
 415         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 416         case Opt_vers_2:
 417                 ctx->version = 2;
 418                 break;
 419         case Opt_vers_3:
 420                 ctx->flags |= NFS_MOUNT_VER3;
 421                 ctx->version = 3;
 422                 break;
 423         case Opt_vers_4:
 424                 /* Backward compatibility option. In future,
 425                  * the mount program should always supply
 426                  * a NFSv4 minor version number.
 427                  */
 428                 ctx->version = 4;
 429                 break;
 430         case Opt_vers_4_0:
 431                 ctx->version = 4;
 432                 ctx->minorversion = 0;
 433                 break;
 434         case Opt_vers_4_1:
 435                 ctx->version = 4;
 436                 ctx->minorversion = 1;
 437                 break;
 438         case Opt_vers_4_2:
 439                 ctx->version = 4;
 440                 ctx->minorversion = 2;
 441                 break;
 442         default:
 443                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 444         }
 445         return 0;
 446 }
 447
 448 /*
 449  * Parse a single mount parameter.
 450  */
 451 static int nfs_fs_context_parse_param(struct fs_context *fc,
 452                                       struct fs_parameter *param)
 453 {
 454         struct fs_parse_result result;
 455         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 456         unsigned short protofamily, mountfamily;
 457         unsigned int len;
 458         int ret, opt;
 459
 460         dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", param->key);
 461
 462         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 463         if (opt < 0)
 464                 return ctx->sloppy ? 1 : opt;
 465
 466         switch (opt) {
 467         case Opt_source:
 468                 if (fc->source)
 469                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 470                 fc->source = param->string;
 471                 param->string = NULL;
 472                 break;
 473
 474                 /*
 475                  * boolean options:  foo/nofoo
 476                  */
 477         case Opt_soft:
 478                 ctx->flags |= NFS_MOUNT_SOFT;
 479                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 480                 break;
 481         case Opt_softerr:
 482                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 483                 ctx->flags &= ~NFS_MOUNT_SOFT;
 484                 break;
 485         case Opt_hard:
 486                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 487                                 NFS_MOUNT_SOFTERR |
 488                                 NFS_MOUNT_SOFTREVAL);
 489                 break;
 490         case Opt_softreval:
 491                 if (result.negated)
 492                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 493                 else
 494                         ctx->flags &= NFS_MOUNT_SOFTREVAL;
 495                 break;
 496         case Opt_posix:
 497                 if (result.negated)
 498                         ctx->flags &= ~NFS_MOUNT_POSIX;
 499                 else
 500                         ctx->flags |= NFS_MOUNT_POSIX;
 501                 break;
 502         case Opt_cto:
 503                 if (result.negated)
 504                         ctx->flags |= NFS_MOUNT_NOCTO;
 505                 else
 506                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 507                 break;
 508         case Opt_ac:
 509                 if (result.negated)
 510                         ctx->flags |= NFS_MOUNT_NOAC;
 511                 else
 512                         ctx->flags &= ~NFS_MOUNT_NOAC;
 513                 break;
 514         case Opt_lock:
 515                 if (result.negated) {
 516                         ctx->flags |= NFS_MOUNT_NONLM;
 517                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 518                 } else {
 519                         ctx->flags &= ~NFS_MOUNT_NONLM;
 520                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 521                 }
 522                 break;
 523         case Opt_udp:
 524                 ctx->flags &= ~NFS_MOUNT_TCP;
 525                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 526                 break;
 527         case Opt_tcp:
 528         case Opt_rdma:
 529                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 530                 ret = xprt_find_transport_ident(param->key);
 531                 if (ret < 0)
 532                         goto out_bad_transport;
 533                 ctx->nfs_server.protocol = ret;
 534                 break;
 535         case Opt_acl:
 536                 if (result.negated)
 537                         ctx->flags |= NFS_MOUNT_NOACL;
 538                 else
 539                         ctx->flags &= ~NFS_MOUNT_NOACL;
 540                 break;
 541         case Opt_rdirplus:
 542                 if (result.negated)
 543                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 544                 else
 545                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 546                 break;
 547         case Opt_sharecache:
 548                 if (result.negated)
 549                         ctx->flags |= NFS_MOUNT_UNSHARED;
 550                 else
 551                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 552                 break;
 553         case Opt_resvport:
 554                 if (result.negated)
 555                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 556                 else
 557                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 558                 break;
 559         case Opt_fscache_flag:
 560                 if (result.negated)
 561                         ctx->options &= ~NFS_OPTION_FSCACHE;
 562                 else
 563                         ctx->options |= NFS_OPTION_FSCACHE;
 564                 kfree(ctx->fscache_uniq);
 565                 ctx->fscache_uniq = NULL;
 566                 break;
 567         case Opt_fscache:
 568                 ctx->options |= NFS_OPTION_FSCACHE;
 569                 kfree(ctx->fscache_uniq);
 570                 ctx->fscache_uniq = param->string;
 571                 param->string = NULL;
 572                 break;
 573         case Opt_migration:
 574                 if (result.negated)
 575                         ctx->options &= ~NFS_OPTION_MIGRATION;
 576                 else
 577                         ctx->options |= NFS_OPTION_MIGRATION;
 578                 break;
 579
 580                 /*
 581                  * options that take numeric values
 582                  */
 583         case Opt_port:
 584                 if (result.uint_32 > USHRT_MAX)
 585                         goto out_of_bounds;
 586                 ctx->nfs_server.port = result.uint_32;
 587                 break;
 588         case Opt_rsize:
 589                 ctx->rsize = result.uint_32;
 590                 break;
 591         case Opt_wsize:
 592                 ctx->wsize = result.uint_32;
 593                 break;
 594         case Opt_bsize:
 595                 ctx->bsize = result.uint_32;
 596                 break;
 597         case Opt_timeo:
 598                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 599                         goto out_of_bounds;
 600                 ctx->timeo = result.uint_32;
 601                 break;
 602         case Opt_retrans:
 603                 if (result.uint_32 > INT_MAX)
 604                         goto out_of_bounds;
 605                 ctx->retrans = result.uint_32;
 606                 break;
 607         case Opt_acregmin:
 608                 ctx->acregmin = result.uint_32;
 609                 break;
 610         case Opt_acregmax:
 611                 ctx->acregmax = result.uint_32;
 612                 break;
 613         case Opt_acdirmin:
 614                 ctx->acdirmin = result.uint_32;
 615                 break;
 616         case Opt_acdirmax:
 617                 ctx->acdirmax = result.uint_32;
 618                 break;
 619         case Opt_actimeo:
 620                 ctx->acregmin = result.uint_32;
 621                 ctx->acregmax = result.uint_32;
 622                 ctx->acdirmin = result.uint_32;
 623                 ctx->acdirmax = result.uint_32;
 624                 break;
 625         case Opt_namelen:
 626                 ctx->namlen = result.uint_32;
 627                 break;
 628         case Opt_mountport:
 629                 if (result.uint_32 > USHRT_MAX)
 630                         goto out_of_bounds;
 631                 ctx->mount_server.port = result.uint_32;
 632                 break;
 633         case Opt_mountvers:
 634                 if (result.uint_32 < NFS_MNT_VERSION ||
 635                     result.uint_32 > NFS_MNT3_VERSION)
 636                         goto out_of_bounds;
 637                 ctx->mount_server.version = result.uint_32;
 638                 break;
 639         case Opt_minorversion:
 640                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 641                         goto out_of_bounds;
 642                 ctx->minorversion = result.uint_32;
 643                 break;
 644
 645                 /*
 646                  * options that take text values
 647                  */
 648         case Opt_v:
 649                 ret = nfs_parse_version_string(fc, param->key + 1);
 650                 if (ret < 0)
 651                         return ret;
 652                 break;
 653         case Opt_vers:
 654                 ret = nfs_parse_version_string(fc, param->string);
 655                 if (ret < 0)
 656                         return ret;
 657                 break;
 658         case Opt_sec:
 659                 ret = nfs_parse_security_flavors(fc, param);
 660                 if (ret < 0)
 661                         return ret;
 662                 break;
 663
 664         case Opt_proto:
 665                 protofamily = AF_INET;
 666                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 667                 case Opt_xprt_udp6:
 668                         protofamily = AF_INET6;
 669                         fallthrough;
 670                 case Opt_xprt_udp:
 671                         ctx->flags &= ~NFS_MOUNT_TCP;
 672                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 673                         break;
 674                 case Opt_xprt_tcp6:
 675                         protofamily = AF_INET6;
 676                         fallthrough;
 677                 case Opt_xprt_tcp:
 678                         ctx->flags |= NFS_MOUNT_TCP;
 679                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 680                         break;
 681                 case Opt_xprt_rdma6:
 682                         protofamily = AF_INET6;
 683                         fallthrough;
 684                 case Opt_xprt_rdma:
 685                         /* vector side protocols to TCP */
 686                         ctx->flags |= NFS_MOUNT_TCP;
 687                         ret = xprt_find_transport_ident(param->string);
 688                         if (ret < 0)
 689                                 goto out_bad_transport;
 690                         ctx->nfs_server.protocol = ret;
 691                         break;
 692                 default:
 693                         goto out_bad_transport;
 694                 }
 695
 696                 ctx->protofamily = protofamily;
 697                 break;
 698
 699         case Opt_mountproto:
 700                 mountfamily = AF_INET;
 701                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 702                 case Opt_xprt_udp6:
 703                         mountfamily = AF_INET6;
 704                         fallthrough;
 705                 case Opt_xprt_udp:
 706                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 707                         break;
 708                 case Opt_xprt_tcp6:
 709                         mountfamily = AF_INET6;
 710                         fallthrough;
 711                 case Opt_xprt_tcp:
 712                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 713                         break;
 714                 case Opt_xprt_rdma: /* not used for side protocols */
 715                 default:
 716                         goto out_bad_transport;
 717                 }
 718                 ctx->mountfamily = mountfamily;
 719                 break;
 720
 721         case Opt_addr:
 722                 len = rpc_pton(fc->net_ns, param->string, param->size,
 723                                &ctx->nfs_server.address,
 724                                sizeof(ctx->nfs_server._address));
 725                 if (len == 0)
 726                         goto out_invalid_address;
 727                 ctx->nfs_server.addrlen = len;
 728                 break;
 729         case Opt_clientaddr:
 730                 kfree(ctx->client_address);
 731                 ctx->client_address = param->string;
 732                 param->string = NULL;
 733                 break;
 734         case Opt_mounthost:
 735                 kfree(ctx->mount_server.hostname);
 736                 ctx->mount_server.hostname = param->string;
 737                 param->string = NULL;
 738                 break;
 739         case Opt_mountaddr:
 740                 len = rpc_pton(fc->net_ns, param->string, param->size,
 741                                &ctx->mount_server.address,
 742                                sizeof(ctx->mount_server._address));
 743                 if (len == 0)
 744                         goto out_invalid_address;
 745                 ctx->mount_server.addrlen = len;
 746                 break;
 747         case Opt_nconnect:
 748                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 749                         goto out_of_bounds;
 750                 ctx->nfs_server.nconnect = result.uint_32;
 751                 break;
 752         case Opt_lookupcache:
 753                 switch (result.uint_32) {
 754                 case Opt_lookupcache_all:
 755                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 756                         break;
 757                 case Opt_lookupcache_positive:
 758                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 759                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 760                         break;
 761                 case Opt_lookupcache_none:
 762                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 763                         break;
 764                 default:
 765                         goto out_invalid_value;
 766                 }
 767                 break;
 768         case Opt_local_lock:
 769                 switch (result.uint_32) {
 770                 case Opt_local_lock_all:
 771                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 772                                        NFS_MOUNT_LOCAL_FCNTL);
 773                         break;
 774                 case Opt_local_lock_flock:
 775                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 776                         break;
 777                 case Opt_local_lock_posix:
 778                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 779                         break;
 780                 case Opt_local_lock_none:
 781                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 782                                         NFS_MOUNT_LOCAL_FCNTL);
 783                         break;
 784                 default:
 785                         goto out_invalid_value;
 786                 }
 787                 break;
 788         case Opt_write:
 789                 switch (result.uint_32) {
 790                 case Opt_write_lazy:
 791                         ctx->flags &=
 792                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 793                         break;
 794                 case Opt_write_eager:
 795                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 796                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 797                         break;
 798                 case Opt_write_wait:
 799                         ctx->flags |=
 800                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 801                         break;
 802                 default:
 803                         goto out_invalid_value;
 804                 }
 805                 break;
 806
 807                 /*
 808                  * Special options
 809                  */
 810         case Opt_sloppy:
 811                 ctx->sloppy = true;
 812                 dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
 813                 break;
 814         }
 815
 816         return 0;
 817
 818 out_invalid_value:
 819         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 820 out_invalid_address:
 821         return nfs_invalf(fc, "NFS: Bad IP address specified");
 822 out_of_bounds:
 823         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 824 out_bad_transport:
 825         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 826 }
 827
 828 /*
 829  * Split fc->source into "hostname:export_path".
 830  *
 831  * The leftmost colon demarks the split between the server's hostname
 832  * and the export path.  If the hostname starts with a left square
 833  * bracket, then it may contain colons.
 834  *
 835  * Note: caller frees hostname and export path, even on error.
 836  */
 837 static int nfs_parse_source(struct fs_context *fc,
 838                             size_t maxnamlen, size_t maxpathlen)
 839 {
 840         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 841         const char *dev_name = fc->source;
 842         size_t len;
 843         const char *end;
 844
 845         if (unlikely(!dev_name || !*dev_name)) {
 846                 dfprintk(MOUNT, "NFS: device name not specified\n");
 847                 return -EINVAL;
 848         }
 849
 850         /* Is the host name protected with square brakcets? */
 851         if (*dev_name == '[') {
 852                 end = strchr(++dev_name, ']');
 853                 if (end == NULL || end[1] != ':')
 854                         goto out_bad_devname;
 855
 856                 len = end - dev_name;
 857                 end++;
 858         } else {
 859                 const char *comma;
 860
 861                 end = strchr(dev_name, ':');
 862                 if (end == NULL)
 863                         goto out_bad_devname;
 864                 len = end - dev_name;
 865
 866                 /* kill possible hostname list: not supported */
 867                 comma = memchr(dev_name, ',', len);
 868                 if (comma)
 869                         len = comma - dev_name;
 870         }
 871
 872         if (len > maxnamlen)
 873                 goto out_hostname;
 874
 875         kfree(ctx->nfs_server.hostname);
 876
 877         /* N.B. caller will free nfs_server.hostname in all cases */
 878         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 879         if (!ctx->nfs_server.hostname)
 880                 goto out_nomem;
 881         len = strlen(++end);
 882         if (len > maxpathlen)
 883                 goto out_path;
 884         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
 885         if (!ctx->nfs_server.export_path)
 886                 goto out_nomem;
 887
 888         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
 889         return 0;
 890
 891 out_bad_devname:
 892         return nfs_invalf(fc, "NFS: device name not in host:path format");
 893 out_nomem:
 894         nfs_errorf(fc, "NFS: not enough memory to parse device name");
 895         return -ENOMEM;
 896 out_hostname:
 897         nfs_errorf(fc, "NFS: server hostname too long");
 898         return -ENAMETOOLONG;
 899 out_path:
 900         nfs_errorf(fc, "NFS: export pathname too long");
 901         return -ENAMETOOLONG;
 902 }
 903
 904 static inline bool is_remount_fc(struct fs_context *fc)
 905 {
 906         return fc->root != NULL;
 907 }
 908
 909 /*
 910  * Parse monolithic NFS2/NFS3 mount data
 911  * - fills in the mount root filehandle
 912  *
 913  * For option strings, user space handles the following behaviors:
 914  *
 915  * + DNS: mapping server host name to IP address ("addr=" option)
 916  *
 917  * + failure mode: how to behave if a mount request can't be handled
 918  *   immediately ("fg/bg" option)
 919  *
 920  * + retry: how often to retry a mount request ("retry=" option)
 921  *
 922  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
 923  *   mountproto=tcp after mountproto=udp, and so on
 924  */
 925 static int nfs23_parse_monolithic(struct fs_context *fc,
 926                                   struct nfs_mount_data *data)
 927 {
 928         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 929         struct nfs_fh *mntfh = ctx->mntfh;
 930         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
 931         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
 932
 933         if (data == NULL)
 934                 goto out_no_data;
 935
 936         ctx->version = NFS_DEFAULT_VERSION;
 937         switch (data->version) {
 938         case 1:
 939                 data->namlen = 0;
 940                 fallthrough;
 941         case 2:
 942                 data->bsize = 0;
 943                 fallthrough;
 944         case 3:
 945                 if (data->flags & NFS_MOUNT_VER3)
 946                         goto out_no_v3;
 947                 data->root.size = NFS2_FHSIZE;
 948                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
 949                 /* Turn off security negotiation */
 950                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
 951                 fallthrough;
 952         case 4:
 953                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
 954                         goto out_no_sec;
 955                 fallthrough;
 956         case 5:
 957                 memset(data->context, 0, sizeof(data->context));
 958                 fallthrough;
 959         case 6:
 960                 if (data->flags & NFS_MOUNT_VER3) {
 961                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
 962                                 goto out_invalid_fh;
 963                         mntfh->size = data->root.size;
 964                         ctx->version = 3;
 965                 } else {
 966                         mntfh->size = NFS2_FHSIZE;
 967                         ctx->version = 2;
 968                 }
 969
 970
 971                 memcpy(mntfh->data, data->root.data, mntfh->size);
 972                 if (mntfh->size < sizeof(mntfh->data))
 973                         memset(mntfh->data + mntfh->size, 0,
 974                                sizeof(mntfh->data) - mntfh->size);
 975
 976                 /*
 977                  * Translate to nfs_fs_context, which nfs_fill_super
 978                  * can deal with.
 979                  */
 980                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
 981                 ctx->flags      |= extra_flags;
 982                 ctx->rsize      = data->rsize;
 983                 ctx->wsize      = data->wsize;
 984                 ctx->timeo      = data->timeo;
 985                 ctx->retrans    = data->retrans;
 986                 ctx->acregmin   = data->acregmin;
 987                 ctx->acregmax   = data->acregmax;
 988                 ctx->acdirmin   = data->acdirmin;
 989                 ctx->acdirmax   = data->acdirmax;
 990                 ctx->need_mount = false;
 991
 992                 memcpy(sap, &data->addr, sizeof(data->addr));
 993                 ctx->nfs_server.addrlen = sizeof(data->addr);
 994                 ctx->nfs_server.port = ntohs(data->addr.sin_port);
 995                 if (sap->sa_family != AF_INET ||
 996                     !nfs_verify_server_address(sap))
 997                         goto out_no_address;
 998
 999                 if (!(data->flags & NFS_MOUNT_TCP))
1000                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1001                 /* N.B. caller will free nfs_server.hostname in all cases */
1002                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1003                 if (!ctx->nfs_server.hostname)
1004                         goto out_nomem;
1005
1006                 ctx->namlen             = data->namlen;
1007                 ctx->bsize              = data->bsize;
1008
1009                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1010                         ctx->selected_flavor = data->pseudoflavor;
1011                 else
1012                         ctx->selected_flavor = RPC_AUTH_UNIX;
1013
1014                 if (!(data->flags & NFS_MOUNT_NONLM))
1015                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1016                                          NFS_MOUNT_LOCAL_FCNTL);
1017                 else
1018                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1019                                         NFS_MOUNT_LOCAL_FCNTL);
1020
1021                 /*
1022                  * The legacy version 6 binary mount data from userspace has a
1023                  * field used only to transport selinux information into the
1024                  * kernel.  To continue to support that functionality we
1025                  * have a touch of selinux knowledge here in the NFS code. The
1026                  * userspace code converted context=blah to just blah so we are
1027                  * converting back to the full string selinux understands.
1028                  */
1029                 if (data->context[0]){
1030 #ifdef CONFIG_SECURITY_SELINUX
1031                         int ret;
1032
1033                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1034                         ret = vfs_parse_fs_string(fc, "context",
1035                                                   data->context, strlen(data->context));
1036                         if (ret < 0)
1037                                 return ret;
1038 #else
1039                         return -EINVAL;
1040 #endif
1041                 }
1042
1043                 break;
1044         default:
1045                 goto generic;
1046         }
1047
1048         ctx->skip_reconfig_option_check = true;
1049         return 0;
1050
1051 generic:
1052         return generic_parse_monolithic(fc, data);
1053
1054 out_no_data:
1055         if (is_remount_fc(fc)) {
1056                 ctx->skip_reconfig_option_check = true;
1057                 return 0;
1058         }
1059         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1060
1061 out_no_v3:
1062         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1063
1064 out_no_sec:
1065         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1066
1067 out_nomem:
1068         dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
1069         return -ENOMEM;
1070
1071 out_no_address:
1072         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1073
1074 out_invalid_fh:
1075         return nfs_invalf(fc, "NFS: invalid root filehandle");
1076 }
1077
1078 #if IS_ENABLED(CONFIG_NFS_V4)
1079 struct compat_nfs_string {
1080         compat_uint_t len;
1081         compat_uptr_t data;
1082 };
1083
1084 static inline void compat_nfs_string(struct nfs_string *dst,
1085                                      struct compat_nfs_string *src)
1086 {
1087         dst->data = compat_ptr(src->data);
1088         dst->len = src->len;
1089 }
1090
1091 struct compat_nfs4_mount_data_v1 {
1092         compat_int_t version;
1093         compat_int_t flags;
1094         compat_int_t rsize;
1095         compat_int_t wsize;
1096         compat_int_t timeo;
1097         compat_int_t retrans;
1098         compat_int_t acregmin;
1099         compat_int_t acregmax;
1100         compat_int_t acdirmin;
1101         compat_int_t acdirmax;
1102         struct compat_nfs_string client_addr;
1103         struct compat_nfs_string mnt_path;
1104         struct compat_nfs_string hostname;
1105         compat_uint_t host_addrlen;
1106         compat_uptr_t host_addr;
1107         compat_int_t proto;
1108         compat_int_t auth_flavourlen;
1109         compat_uptr_t auth_flavours;
1110 };
1111
1112 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1113 {
1114         struct compat_nfs4_mount_data_v1 *compat =
1115                         (struct compat_nfs4_mount_data_v1 *)data;
1116
1117         /* copy the fields backwards */
1118         data->auth_flavours = compat_ptr(compat->auth_flavours);
1119         data->auth_flavourlen = compat->auth_flavourlen;
1120         data->proto = compat->proto;
1121         data->host_addr = compat_ptr(compat->host_addr);
1122         data->host_addrlen = compat->host_addrlen;
1123         compat_nfs_string(&data->hostname, &compat->hostname);
1124         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1125         compat_nfs_string(&data->client_addr, &compat->client_addr);
1126         data->acdirmax = compat->acdirmax;
1127         data->acdirmin = compat->acdirmin;
1128         data->acregmax = compat->acregmax;
1129         data->acregmin = compat->acregmin;
1130         data->retrans = compat->retrans;
1131         data->timeo = compat->timeo;
1132         data->wsize = compat->wsize;
1133         data->rsize = compat->rsize;
1134         data->flags = compat->flags;
1135         data->version = compat->version;
1136 }
1137
1138 /*
1139  * Validate NFSv4 mount options
1140  */
1141 static int nfs4_parse_monolithic(struct fs_context *fc,
1142                                  struct nfs4_mount_data *data)
1143 {
1144         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1145         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1146         char *c;
1147
1148         if (!data) {
1149                 if (is_remount_fc(fc))
1150                         goto done;
1151                 return nfs_invalf(fc,
1152                         "NFS4: mount program didn't pass any mount data");
1153         }
1154
1155         ctx->version = 4;
1156
1157         if (data->version != 1)
1158                 return generic_parse_monolithic(fc, data);
1159
1160         if (in_compat_syscall())
1161                 nfs4_compat_mount_data_conv(data);
1162
1163         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1164                 goto out_no_address;
1165         if (data->host_addrlen == 0)
1166                 goto out_no_address;
1167         ctx->nfs_server.addrlen = data->host_addrlen;
1168         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1169                 return -EFAULT;
1170         if (!nfs_verify_server_address(sap))
1171                 goto out_no_address;
1172         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1173
1174         if (data->auth_flavourlen) {
1175                 rpc_authflavor_t pseudoflavor;
1176
1177                 if (data->auth_flavourlen > 1)
1178                         goto out_inval_auth;
1179                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1180                                    sizeof(pseudoflavor)))
1181                         return -EFAULT;
1182                 ctx->selected_flavor = pseudoflavor;
1183         } else {
1184                 ctx->selected_flavor = RPC_AUTH_UNIX;
1185         }
1186
1187         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1188         if (IS_ERR(c))
1189                 return PTR_ERR(c);
1190         ctx->nfs_server.hostname = c;
1191
1192         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1193         if (IS_ERR(c))
1194                 return PTR_ERR(c);
1195         ctx->nfs_server.export_path = c;
1196         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1197
1198         c = strndup_user(data->client_addr.data, 16);
1199         if (IS_ERR(c))
1200                 return PTR_ERR(c);
1201         ctx->client_address = c;
1202
1203         /*
1204          * Translate to nfs_fs_context, which nfs_fill_super
1205          * can deal with.
1206          */
1207
1208         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1209         ctx->rsize      = data->rsize;
1210         ctx->wsize      = data->wsize;
1211         ctx->timeo      = data->timeo;
1212         ctx->retrans    = data->retrans;
1213         ctx->acregmin   = data->acregmin;
1214         ctx->acregmax   = data->acregmax;
1215         ctx->acdirmin   = data->acdirmin;
1216         ctx->acdirmax   = data->acdirmax;
1217         ctx->nfs_server.protocol = data->proto;
1218         nfs_validate_transport_protocol(ctx);
1219         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1220                 goto out_invalid_transport_udp;
1221 done:
1222         ctx->skip_reconfig_option_check = true;
1223         return 0;
1224
1225 out_inval_auth:
1226         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1227                       data->auth_flavourlen);
1228
1229 out_no_address:
1230         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1231
1232 out_invalid_transport_udp:
1233         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
1234 }
1235 #endif
1236
1237 /*
1238  * Parse a monolithic block of data from sys_mount().
1239  */
1240 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1241                                            void *data)
1242 {
1243         if (fc->fs_type == &nfs_fs_type)
1244                 return nfs23_parse_monolithic(fc, data);
1245
1246 #if IS_ENABLED(CONFIG_NFS_V4)
1247         if (fc->fs_type == &nfs4_fs_type)
1248                 return nfs4_parse_monolithic(fc, data);
1249 #endif
1250
1251         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1252 }
1253
1254 /*
1255  * Validate the preparsed information in the config.
1256  */
1257 static int nfs_fs_context_validate(struct fs_context *fc)
1258 {
1259         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1260         struct nfs_subversion *nfs_mod;
1261         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1262         int max_namelen = PAGE_SIZE;
1263         int max_pathlen = NFS_MAXPATHLEN;
1264         int port = 0;
1265         int ret;
1266
1267         if (!fc->source)
1268                 goto out_no_device_name;
1269
1270         /* Check for sanity first. */
1271         if (ctx->minorversion && ctx->version != 4)
1272                 goto out_minorversion_mismatch;
1273
1274         if (ctx->options & NFS_OPTION_MIGRATION &&
1275             (ctx->version != 4 || ctx->minorversion != 0))
1276                 goto out_migration_misuse;
1277
1278         /* Verify that any proto=/mountproto= options match the address
1279          * families in the addr=/mountaddr= options.
1280          */
1281         if (ctx->protofamily != AF_UNSPEC &&
1282             ctx->protofamily != ctx->nfs_server.address.sa_family)
1283                 goto out_proto_mismatch;
1284
1285         if (ctx->mountfamily != AF_UNSPEC) {
1286                 if (ctx->mount_server.addrlen) {
1287                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1288                                 goto out_mountproto_mismatch;
1289                 } else {
1290                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1291                                 goto out_mountproto_mismatch;
1292                 }
1293         }
1294
1295         if (!nfs_verify_server_address(sap))
1296                 goto out_no_address;
1297
1298         if (ctx->version == 4) {
1299                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1300                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1301                                 port = NFS_RDMA_PORT;
1302                         else
1303                                 port = NFS_PORT;
1304                         max_namelen = NFS4_MAXNAMLEN;
1305                         max_pathlen = NFS4_MAXPATHLEN;
1306                         nfs_validate_transport_protocol(ctx);
1307                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1308                                 goto out_invalid_transport_udp;
1309                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1310                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1311                                         NFS_MOUNT_LOCAL_FCNTL);
1312                 } else {
1313                         goto out_v4_not_compiled;
1314                 }
1315         } else {
1316                 nfs_set_mount_transport_protocol(ctx);
1317 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
1318                if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1319                        goto out_invalid_transport_udp;
1320 #endif
1321                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1322                         port = NFS_RDMA_PORT;
1323         }
1324
1325         nfs_set_port(sap, &ctx->nfs_server.port, port);
1326
1327         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1328         if (ret < 0)
1329                 return ret;
1330
1331         /* Load the NFS protocol module if we haven't done so yet */
1332         if (!ctx->nfs_mod) {
1333                 nfs_mod = get_nfs_version(ctx->version);
1334                 if (IS_ERR(nfs_mod)) {
1335                         ret = PTR_ERR(nfs_mod);
1336                         goto out_version_unavailable;
1337                 }
1338                 ctx->nfs_mod = nfs_mod;
1339         }
1340
1341         /* Ensure the filesystem context has the correct fs_type */
1342         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1343                 module_put(fc->fs_type->owner);
1344                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1345                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1346         }
1347         return 0;
1348
1349 out_no_device_name:
1350         return nfs_invalf(fc, "NFS: Device name not specified");
1351 out_v4_not_compiled:
1352         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1353         return -EPROTONOSUPPORT;
1354 out_invalid_transport_udp:
1355         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
1356 out_no_address:
1357         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1358 out_mountproto_mismatch:
1359         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1360 out_proto_mismatch:
1361         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1362 out_minorversion_mismatch:
1363         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1364                           ctx->version, ctx->minorversion);
1365 out_migration_misuse:
1366         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1367 out_version_unavailable:
1368         nfs_errorf(fc, "NFS: Version unavailable");
1369         return ret;
1370 }
1371
1372 /*
1373  * Create an NFS superblock by the appropriate method.
1374  */
1375 static int nfs_get_tree(struct fs_context *fc)
1376 {
1377         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1378         int err = nfs_fs_context_validate(fc);
1379
1380         if (err)
1381                 return err;
1382         if (!ctx->internal)
1383                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1384         else
1385                 return nfs_get_tree_common(fc);
1386 }
1387
1388 /*
1389  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1390  * it can't deal with resource pointers in the filesystem context, so we have
1391  * to do that.  We need to clear pointers, copy data or get extra refs as
1392  * appropriate.
1393  */
1394 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1395 {
1396         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1397
1398         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1399         if (!ctx)
1400                 return -ENOMEM;
1401
1402         ctx->mntfh = nfs_alloc_fhandle();
1403         if (!ctx->mntfh) {
1404                 kfree(ctx);
1405                 return -ENOMEM;
1406         }
1407         nfs_copy_fh(ctx->mntfh, src->mntfh);
1408
1409         __module_get(ctx->nfs_mod->owner);
1410         ctx->client_address             = NULL;
1411         ctx->mount_server.hostname      = NULL;
1412         ctx->nfs_server.export_path     = NULL;
1413         ctx->nfs_server.hostname        = NULL;
1414         ctx->fscache_uniq               = NULL;
1415         ctx->clone_data.fattr           = NULL;
1416         fc->fs_private = ctx;
1417         return 0;
1418 }
1419
1420 static void nfs_fs_context_free(struct fs_context *fc)
1421 {
1422         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1423
1424         if (ctx) {
1425                 if (ctx->server)
1426                         nfs_free_server(ctx->server);
1427                 if (ctx->nfs_mod)
1428                         put_nfs_version(ctx->nfs_mod);
1429                 kfree(ctx->client_address);
1430                 kfree(ctx->mount_server.hostname);
1431                 kfree(ctx->nfs_server.export_path);
1432                 kfree(ctx->nfs_server.hostname);
1433                 kfree(ctx->fscache_uniq);
1434                 nfs_free_fhandle(ctx->mntfh);
1435                 nfs_free_fattr(ctx->clone_data.fattr);
1436                 kfree(ctx);
1437         }
1438 }
1439
1440 static const struct fs_context_operations nfs_fs_context_ops = {
1441         .free                   = nfs_fs_context_free,
1442         .dup                    = nfs_fs_context_dup,
1443         .parse_param            = nfs_fs_context_parse_param,
1444         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1445         .get_tree               = nfs_get_tree,
1446         .reconfigure            = nfs_reconfigure,
1447 };
1448
1449 /*
1450  * Prepare superblock configuration.  We use the namespaces attached to the
1451  * context.  This may be the current process's namespaces, or it may be a
1452  * container's namespaces.
1453  */
1454 static int nfs_init_fs_context(struct fs_context *fc)
1455 {
1456         struct nfs_fs_context *ctx;
1457
1458         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1459         if (unlikely(!ctx))
1460                 return -ENOMEM;
1461
1462         ctx->mntfh = nfs_alloc_fhandle();
1463         if (unlikely(!ctx->mntfh)) {
1464                 kfree(ctx);
1465                 return -ENOMEM;
1466         }
1467
1468         ctx->protofamily        = AF_UNSPEC;
1469         ctx->mountfamily        = AF_UNSPEC;
1470         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1471
1472         if (fc->root) {
1473                 /* reconfigure, start with the current config */
1474                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1475                 struct net *net = nfss->nfs_client->cl_net;
1476
1477                 ctx->flags              = nfss->flags;
1478                 ctx->rsize              = nfss->rsize;
1479                 ctx->wsize              = nfss->wsize;
1480                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1481                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1482                 ctx->acregmin           = nfss->acregmin / HZ;
1483                 ctx->acregmax           = nfss->acregmax / HZ;
1484                 ctx->acdirmin           = nfss->acdirmin / HZ;
1485                 ctx->acdirmax           = nfss->acdirmax / HZ;
1486                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1487                 ctx->nfs_server.port    = nfss->port;
1488                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1489                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1490                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1491
1492                 memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
1493                         ctx->nfs_server.addrlen);
1494
1495                 if (fc->net_ns != net) {
1496                         put_net(fc->net_ns);
1497                         fc->net_ns = get_net(net);
1498                 }
1499
1500                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1501                 __module_get(ctx->nfs_mod->owner);
1502         } else {
1503                 /* defaults */
1504                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1505                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1506                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1507                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1508                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1509                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1510                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1511                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1512                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1513                 ctx->minorversion       = 0;
1514                 ctx->need_mount         = true;
1515
1516                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1517         }
1518         fc->fs_private = ctx;
1519         fc->ops = &nfs_fs_context_ops;
1520         return 0;
1521 }
1522
1523 struct file_system_type nfs_fs_type = {
1524         .owner                  = THIS_MODULE,
1525         .name                   = "nfs",
1526         .init_fs_context        = nfs_init_fs_context,
1527         .parameters             = nfs_fs_parameters,
1528         .kill_sb                = nfs_kill_super,
1529         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1530 };
1531 MODULE_ALIAS_FS("nfs");
1532 EXPORT_SYMBOL_GPL(nfs_fs_type);
1533
1534 #if IS_ENABLED(CONFIG_NFS_V4)
1535 struct file_system_type nfs4_fs_type = {
1536         .owner                  = THIS_MODULE,
1537         .name                   = "nfs4",
1538         .init_fs_context        = nfs_init_fs_context,
1539         .parameters             = nfs_fs_parameters,
1540         .kill_sb                = nfs_kill_super,
1541         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1542 };
1543 MODULE_ALIAS_FS("nfs4");
1544 MODULE_ALIAS("nfs4");
1545 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1546 #endif /* CONFIG_NFS_V4 */