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/compat.h>
  14 #include <linux/module.h>
  15 #include <linux/fs.h>
  16 #include <linux/fs_context.h>
  17 #include <linux/fs_parser.h>
  18 #include <linux/nfs_fs.h>
  19 #include <linux/nfs_mount.h>
  20 #include <linux/nfs4_mount.h>
  21 #include "nfs.h"
  22 #include "internal.h"
  23
  24 #define NFSDBG_FACILITY         NFSDBG_MOUNT
  25
  26 #if IS_ENABLED(CONFIG_NFS_V3)
  27 #define NFS_DEFAULT_VERSION 3
  28 #else
  29 #define NFS_DEFAULT_VERSION 2
  30 #endif
  31
  32 #define NFS_MAX_CONNECTIONS 16
  33
  34 enum nfs_param {
  35         Opt_ac,
  36         Opt_acdirmax,
  37         Opt_acdirmin,
  38         Opt_acl,
  39         Opt_acregmax,
  40         Opt_acregmin,
  41         Opt_actimeo,
  42         Opt_addr,
  43         Opt_bg,
  44         Opt_bsize,
  45         Opt_clientaddr,
  46         Opt_cto,
  47         Opt_fg,
  48         Opt_fscache,
  49         Opt_fscache_flag,
  50         Opt_hard,
  51         Opt_intr,
  52         Opt_local_lock,
  53         Opt_lock,
  54         Opt_lookupcache,
  55         Opt_migration,
  56         Opt_minorversion,
  57         Opt_mountaddr,
  58         Opt_mounthost,
  59         Opt_mountport,
  60         Opt_mountproto,
  61         Opt_mountvers,
  62         Opt_namelen,
  63         Opt_nconnect,
  64         Opt_max_connect,
  65         Opt_port,
  66         Opt_posix,
  67         Opt_proto,
  68         Opt_rdirplus,
  69         Opt_rdma,
  70         Opt_resvport,
  71         Opt_retrans,
  72         Opt_retry,
  73         Opt_rsize,
  74         Opt_sec,
  75         Opt_sharecache,
  76         Opt_sloppy,
  77         Opt_soft,
  78         Opt_softerr,
  79         Opt_softreval,
  80         Opt_source,
  81         Opt_tcp,
  82         Opt_timeo,
  83         Opt_udp,
  84         Opt_v,
  85         Opt_vers,
  86         Opt_wsize,
  87         Opt_write,
  88 };
  89
  90 enum {
  91         Opt_local_lock_all,
  92         Opt_local_lock_flock,
  93         Opt_local_lock_none,
  94         Opt_local_lock_posix,
  95 };
  96
  97 static const struct constant_table nfs_param_enums_local_lock[] = {
  98         { "all",                Opt_local_lock_all },
  99         { "flock",      Opt_local_lock_flock },
 100         { "posix",      Opt_local_lock_posix },
 101         { "none",               Opt_local_lock_none },
 102         {}
 103 };
 104
 105 enum {
 106         Opt_lookupcache_all,
 107         Opt_lookupcache_none,
 108         Opt_lookupcache_positive,
 109 };
 110
 111 static const struct constant_table nfs_param_enums_lookupcache[] = {
 112         { "all",                Opt_lookupcache_all },
 113         { "none",               Opt_lookupcache_none },
 114         { "pos",                Opt_lookupcache_positive },
 115         { "positive",           Opt_lookupcache_positive },
 116         {}
 117 };
 118
 119 enum {
 120         Opt_write_lazy,
 121         Opt_write_eager,
 122         Opt_write_wait,
 123 };
 124
 125 static const struct constant_table nfs_param_enums_write[] = {
 126         { "lazy",               Opt_write_lazy },
 127         { "eager",              Opt_write_eager },
 128         { "wait",               Opt_write_wait },
 129         {}
 130 };
 131
 132 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 133         fsparam_flag_no("ac",           Opt_ac),
 134         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 135         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 136         fsparam_flag_no("acl",          Opt_acl),
 137         fsparam_u32   ("acregmax",      Opt_acregmax),
 138         fsparam_u32   ("acregmin",      Opt_acregmin),
 139         fsparam_u32   ("actimeo",       Opt_actimeo),
 140         fsparam_string("addr",          Opt_addr),
 141         fsparam_flag  ("bg",            Opt_bg),
 142         fsparam_u32   ("bsize",         Opt_bsize),
 143         fsparam_string("clientaddr",    Opt_clientaddr),
 144         fsparam_flag_no("cto",          Opt_cto),
 145         fsparam_flag  ("fg",            Opt_fg),
 146         fsparam_flag_no("fsc",          Opt_fscache_flag),
 147         fsparam_string("fsc",           Opt_fscache),
 148         fsparam_flag  ("hard",          Opt_hard),
 149         __fsparam(NULL, "intr",         Opt_intr,
 150                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 151         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 152         fsparam_flag_no("lock",         Opt_lock),
 153         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 154         fsparam_flag_no("migration",    Opt_migration),
 155         fsparam_u32   ("minorversion",  Opt_minorversion),
 156         fsparam_string("mountaddr",     Opt_mountaddr),
 157         fsparam_string("mounthost",     Opt_mounthost),
 158         fsparam_u32   ("mountport",     Opt_mountport),
 159         fsparam_string("mountproto",    Opt_mountproto),
 160         fsparam_u32   ("mountvers",     Opt_mountvers),
 161         fsparam_u32   ("namlen",        Opt_namelen),
 162         fsparam_u32   ("nconnect",      Opt_nconnect),
 163         fsparam_u32   ("max_connect",   Opt_max_connect),
 164         fsparam_string("nfsvers",       Opt_vers),
 165         fsparam_u32   ("port",          Opt_port),
 166         fsparam_flag_no("posix",        Opt_posix),
 167         fsparam_string("proto",         Opt_proto),
 168         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 169         fsparam_flag  ("rdma",          Opt_rdma),
 170         fsparam_flag_no("resvport",     Opt_resvport),
 171         fsparam_u32   ("retrans",       Opt_retrans),
 172         fsparam_string("retry",         Opt_retry),
 173         fsparam_u32   ("rsize",         Opt_rsize),
 174         fsparam_string("sec",           Opt_sec),
 175         fsparam_flag_no("sharecache",   Opt_sharecache),
 176         fsparam_flag  ("sloppy",        Opt_sloppy),
 177         fsparam_flag  ("soft",          Opt_soft),
 178         fsparam_flag  ("softerr",       Opt_softerr),
 179         fsparam_flag  ("softreval",     Opt_softreval),
 180         fsparam_string("source",        Opt_source),
 181         fsparam_flag  ("tcp",           Opt_tcp),
 182         fsparam_u32   ("timeo",         Opt_timeo),
 183         fsparam_flag  ("udp",           Opt_udp),
 184         fsparam_flag  ("v2",            Opt_v),
 185         fsparam_flag  ("v3",            Opt_v),
 186         fsparam_flag  ("v4",            Opt_v),
 187         fsparam_flag  ("v4.0",          Opt_v),
 188         fsparam_flag  ("v4.1",          Opt_v),
 189         fsparam_flag  ("v4.2",          Opt_v),
 190         fsparam_string("vers",          Opt_vers),
 191         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 192         fsparam_u32   ("wsize",         Opt_wsize),
 193         {}
 194 };
 195
 196 enum {
 197         Opt_vers_2,
 198         Opt_vers_3,
 199         Opt_vers_4,
 200         Opt_vers_4_0,
 201         Opt_vers_4_1,
 202         Opt_vers_4_2,
 203 };
 204
 205 static const struct constant_table nfs_vers_tokens[] = {
 206         { "2",          Opt_vers_2 },
 207         { "3",          Opt_vers_3 },
 208         { "4",          Opt_vers_4 },
 209         { "4.0",        Opt_vers_4_0 },
 210         { "4.1",        Opt_vers_4_1 },
 211         { "4.2",        Opt_vers_4_2 },
 212         {}
 213 };
 214
 215 enum {
 216         Opt_xprt_rdma,
 217         Opt_xprt_rdma6,
 218         Opt_xprt_tcp,
 219         Opt_xprt_tcp6,
 220         Opt_xprt_udp,
 221         Opt_xprt_udp6,
 222         nr__Opt_xprt
 223 };
 224
 225 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 226         { "rdma",       Opt_xprt_rdma },
 227         { "rdma6",      Opt_xprt_rdma6 },
 228         { "tcp",        Opt_xprt_tcp },
 229         { "tcp6",       Opt_xprt_tcp6 },
 230         { "udp",        Opt_xprt_udp },
 231         { "udp6",       Opt_xprt_udp6 },
 232         {}
 233 };
 234
 235 enum {
 236         Opt_sec_krb5,
 237         Opt_sec_krb5i,
 238         Opt_sec_krb5p,
 239         Opt_sec_lkey,
 240         Opt_sec_lkeyi,
 241         Opt_sec_lkeyp,
 242         Opt_sec_none,
 243         Opt_sec_spkm,
 244         Opt_sec_spkmi,
 245         Opt_sec_spkmp,
 246         Opt_sec_sys,
 247         nr__Opt_sec
 248 };
 249
 250 static const struct constant_table nfs_secflavor_tokens[] = {
 251         { "krb5",       Opt_sec_krb5 },
 252         { "krb5i",      Opt_sec_krb5i },
 253         { "krb5p",      Opt_sec_krb5p },
 254         { "lkey",       Opt_sec_lkey },
 255         { "lkeyi",      Opt_sec_lkeyi },
 256         { "lkeyp",      Opt_sec_lkeyp },
 257         { "none",       Opt_sec_none },
 258         { "null",       Opt_sec_none },
 259         { "spkm3",      Opt_sec_spkm },
 260         { "spkm3i",     Opt_sec_spkmi },
 261         { "spkm3p",     Opt_sec_spkmp },
 262         { "sys",        Opt_sec_sys },
 263         {}
 264 };
 265
 266 /*
 267  * Sanity-check a server address provided by the mount command.
 268  *
 269  * Address family must be initialized, and address must not be
 270  * the ANY address for that family.
 271  */
 272 static int nfs_verify_server_address(struct sockaddr *addr)
 273 {
 274         switch (addr->sa_family) {
 275         case AF_INET: {
 276                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 277                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 278         }
 279         case AF_INET6: {
 280                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 281                 return !ipv6_addr_any(sa);
 282         }
 283         }
 284
 285         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 286         return 0;
 287 }
 288
 289 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
 290 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 291 {
 292         return true;
 293 }
 294 #else
 295 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 296 {
 297         if (ctx->version == 4)
 298                 return true;
 299         return false;
 300 }
 301 #endif
 302
 303 /*
 304  * Sanity check the NFS transport protocol.
 305  */
 306 static int nfs_validate_transport_protocol(struct fs_context *fc,
 307                                            struct nfs_fs_context *ctx)
 308 {
 309         switch (ctx->nfs_server.protocol) {
 310         case XPRT_TRANSPORT_UDP:
 311                 if (nfs_server_transport_udp_invalid(ctx))
 312                         goto out_invalid_transport_udp;
 313                 break;
 314         case XPRT_TRANSPORT_TCP:
 315         case XPRT_TRANSPORT_RDMA:
 316                 break;
 317         default:
 318                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 319         }
 320         return 0;
 321 out_invalid_transport_udp:
 322         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
 323 }
 324
 325 /*
 326  * For text based NFSv2/v3 mounts, the mount protocol transport default
 327  * settings should depend upon the specified NFS transport.
 328  */
 329 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 330 {
 331         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 332             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 333                         return;
 334         switch (ctx->nfs_server.protocol) {
 335         case XPRT_TRANSPORT_UDP:
 336                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 337                 break;
 338         case XPRT_TRANSPORT_TCP:
 339         case XPRT_TRANSPORT_RDMA:
 340                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 341         }
 342 }
 343
 344 /*
 345  * Add 'flavor' to 'auth_info' if not already present.
 346  * Returns true if 'flavor' ends up in the list, false otherwise
 347  */
 348 static int nfs_auth_info_add(struct fs_context *fc,
 349                              struct nfs_auth_info *auth_info,
 350                              rpc_authflavor_t flavor)
 351 {
 352         unsigned int i;
 353         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 354
 355         /* make sure this flavor isn't already in the list */
 356         for (i = 0; i < auth_info->flavor_len; i++) {
 357                 if (flavor == auth_info->flavors[i])
 358                         return 0;
 359         }
 360
 361         if (auth_info->flavor_len + 1 >= max_flavor_len)
 362                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 363
 364         auth_info->flavors[auth_info->flavor_len++] = flavor;
 365         return 0;
 366 }
 367
 368 /*
 369  * Parse the value of the 'sec=' option.
 370  */
 371 static int nfs_parse_security_flavors(struct fs_context *fc,
 372                                       struct fs_parameter *param)
 373 {
 374         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 375         rpc_authflavor_t pseudoflavor;
 376         char *string = param->string, *p;
 377         int ret;
 378
 379         dfprintk(MOUNT, "NFS: parsing %s=%s option\n", param->key, param->string);
 380
 381         while ((p = strsep(&string, ":")) != NULL) {
 382                 if (!*p)
 383                         continue;
 384                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 385                 case Opt_sec_none:
 386                         pseudoflavor = RPC_AUTH_NULL;
 387                         break;
 388                 case Opt_sec_sys:
 389                         pseudoflavor = RPC_AUTH_UNIX;
 390                         break;
 391                 case Opt_sec_krb5:
 392                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 393                         break;
 394                 case Opt_sec_krb5i:
 395                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 396                         break;
 397                 case Opt_sec_krb5p:
 398                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 399                         break;
 400                 case Opt_sec_lkey:
 401                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 402                         break;
 403                 case Opt_sec_lkeyi:
 404                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 405                         break;
 406                 case Opt_sec_lkeyp:
 407                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 408                         break;
 409                 case Opt_sec_spkm:
 410                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 411                         break;
 412                 case Opt_sec_spkmi:
 413                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 414                         break;
 415                 case Opt_sec_spkmp:
 416                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 417                         break;
 418                 default:
 419                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 420                 }
 421
 422                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 423                 if (ret < 0)
 424                         return ret;
 425         }
 426
 427         return 0;
 428 }
 429
 430 static int nfs_parse_version_string(struct fs_context *fc,
 431                                     const char *string)
 432 {
 433         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 434
 435         ctx->flags &= ~NFS_MOUNT_VER3;
 436         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 437         case Opt_vers_2:
 438                 ctx->version = 2;
 439                 break;
 440         case Opt_vers_3:
 441                 ctx->flags |= NFS_MOUNT_VER3;
 442                 ctx->version = 3;
 443                 break;
 444         case Opt_vers_4:
 445                 /* Backward compatibility option. In future,
 446                  * the mount program should always supply
 447                  * a NFSv4 minor version number.
 448                  */
 449                 ctx->version = 4;
 450                 break;
 451         case Opt_vers_4_0:
 452                 ctx->version = 4;
 453                 ctx->minorversion = 0;
 454                 break;
 455         case Opt_vers_4_1:
 456                 ctx->version = 4;
 457                 ctx->minorversion = 1;
 458                 break;
 459         case Opt_vers_4_2:
 460                 ctx->version = 4;
 461                 ctx->minorversion = 2;
 462                 break;
 463         default:
 464                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 465         }
 466         return 0;
 467 }
 468
 469 /*
 470  * Parse a single mount parameter.
 471  */
 472 static int nfs_fs_context_parse_param(struct fs_context *fc,
 473                                       struct fs_parameter *param)
 474 {
 475         struct fs_parse_result result;
 476         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 477         unsigned short protofamily, mountfamily;
 478         unsigned int len;
 479         int ret, opt;
 480
 481         dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", param->key);
 482
 483         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 484         if (opt < 0)
 485                 return ctx->sloppy ? 1 : opt;
 486
 487         if (fc->security)
 488                 ctx->has_sec_mnt_opts = 1;
 489
 490         switch (opt) {
 491         case Opt_source:
 492                 if (fc->source)
 493                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 494                 fc->source = param->string;
 495                 param->string = NULL;
 496                 break;
 497
 498                 /*
 499                  * boolean options:  foo/nofoo
 500                  */
 501         case Opt_soft:
 502                 ctx->flags |= NFS_MOUNT_SOFT;
 503                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 504                 break;
 505         case Opt_softerr:
 506                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 507                 ctx->flags &= ~NFS_MOUNT_SOFT;
 508                 break;
 509         case Opt_hard:
 510                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 511                                 NFS_MOUNT_SOFTERR |
 512                                 NFS_MOUNT_SOFTREVAL);
 513                 break;
 514         case Opt_softreval:
 515                 if (result.negated)
 516                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 517                 else
 518                         ctx->flags &= NFS_MOUNT_SOFTREVAL;
 519                 break;
 520         case Opt_posix:
 521                 if (result.negated)
 522                         ctx->flags &= ~NFS_MOUNT_POSIX;
 523                 else
 524                         ctx->flags |= NFS_MOUNT_POSIX;
 525                 break;
 526         case Opt_cto:
 527                 if (result.negated)
 528                         ctx->flags |= NFS_MOUNT_NOCTO;
 529                 else
 530                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 531                 break;
 532         case Opt_ac:
 533                 if (result.negated)
 534                         ctx->flags |= NFS_MOUNT_NOAC;
 535                 else
 536                         ctx->flags &= ~NFS_MOUNT_NOAC;
 537                 break;
 538         case Opt_lock:
 539                 if (result.negated) {
 540                         ctx->flags |= NFS_MOUNT_NONLM;
 541                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 542                 } else {
 543                         ctx->flags &= ~NFS_MOUNT_NONLM;
 544                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 545                 }
 546                 break;
 547         case Opt_udp:
 548                 ctx->flags &= ~NFS_MOUNT_TCP;
 549                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 550                 break;
 551         case Opt_tcp:
 552         case Opt_rdma:
 553                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 554                 ret = xprt_find_transport_ident(param->key);
 555                 if (ret < 0)
 556                         goto out_bad_transport;
 557                 ctx->nfs_server.protocol = ret;
 558                 break;
 559         case Opt_acl:
 560                 if (result.negated)
 561                         ctx->flags |= NFS_MOUNT_NOACL;
 562                 else
 563                         ctx->flags &= ~NFS_MOUNT_NOACL;
 564                 break;
 565         case Opt_rdirplus:
 566                 if (result.negated)
 567                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 568                 else
 569                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 570                 break;
 571         case Opt_sharecache:
 572                 if (result.negated)
 573                         ctx->flags |= NFS_MOUNT_UNSHARED;
 574                 else
 575                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 576                 break;
 577         case Opt_resvport:
 578                 if (result.negated)
 579                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 580                 else
 581                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 582                 break;
 583         case Opt_fscache_flag:
 584                 if (result.negated)
 585                         ctx->options &= ~NFS_OPTION_FSCACHE;
 586                 else
 587                         ctx->options |= NFS_OPTION_FSCACHE;
 588                 kfree(ctx->fscache_uniq);
 589                 ctx->fscache_uniq = NULL;
 590                 break;
 591         case Opt_fscache:
 592                 ctx->options |= NFS_OPTION_FSCACHE;
 593                 kfree(ctx->fscache_uniq);
 594                 ctx->fscache_uniq = param->string;
 595                 param->string = NULL;
 596                 break;
 597         case Opt_migration:
 598                 if (result.negated)
 599                         ctx->options &= ~NFS_OPTION_MIGRATION;
 600                 else
 601                         ctx->options |= NFS_OPTION_MIGRATION;
 602                 break;
 603
 604                 /*
 605                  * options that take numeric values
 606                  */
 607         case Opt_port:
 608                 if (result.uint_32 > USHRT_MAX)
 609                         goto out_of_bounds;
 610                 ctx->nfs_server.port = result.uint_32;
 611                 break;
 612         case Opt_rsize:
 613                 ctx->rsize = result.uint_32;
 614                 break;
 615         case Opt_wsize:
 616                 ctx->wsize = result.uint_32;
 617                 break;
 618         case Opt_bsize:
 619                 ctx->bsize = result.uint_32;
 620                 break;
 621         case Opt_timeo:
 622                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 623                         goto out_of_bounds;
 624                 ctx->timeo = result.uint_32;
 625                 break;
 626         case Opt_retrans:
 627                 if (result.uint_32 > INT_MAX)
 628                         goto out_of_bounds;
 629                 ctx->retrans = result.uint_32;
 630                 break;
 631         case Opt_acregmin:
 632                 ctx->acregmin = result.uint_32;
 633                 break;
 634         case Opt_acregmax:
 635                 ctx->acregmax = result.uint_32;
 636                 break;
 637         case Opt_acdirmin:
 638                 ctx->acdirmin = result.uint_32;
 639                 break;
 640         case Opt_acdirmax:
 641                 ctx->acdirmax = result.uint_32;
 642                 break;
 643         case Opt_actimeo:
 644                 ctx->acregmin = result.uint_32;
 645                 ctx->acregmax = result.uint_32;
 646                 ctx->acdirmin = result.uint_32;
 647                 ctx->acdirmax = result.uint_32;
 648                 break;
 649         case Opt_namelen:
 650                 ctx->namlen = result.uint_32;
 651                 break;
 652         case Opt_mountport:
 653                 if (result.uint_32 > USHRT_MAX)
 654                         goto out_of_bounds;
 655                 ctx->mount_server.port = result.uint_32;
 656                 break;
 657         case Opt_mountvers:
 658                 if (result.uint_32 < NFS_MNT_VERSION ||
 659                     result.uint_32 > NFS_MNT3_VERSION)
 660                         goto out_of_bounds;
 661                 ctx->mount_server.version = result.uint_32;
 662                 break;
 663         case Opt_minorversion:
 664                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 665                         goto out_of_bounds;
 666                 ctx->minorversion = result.uint_32;
 667                 break;
 668
 669                 /*
 670                  * options that take text values
 671                  */
 672         case Opt_v:
 673                 ret = nfs_parse_version_string(fc, param->key + 1);
 674                 if (ret < 0)
 675                         return ret;
 676                 break;
 677         case Opt_vers:
 678                 ret = nfs_parse_version_string(fc, param->string);
 679                 if (ret < 0)
 680                         return ret;
 681                 break;
 682         case Opt_sec:
 683                 ret = nfs_parse_security_flavors(fc, param);
 684                 if (ret < 0)
 685                         return ret;
 686                 break;
 687
 688         case Opt_proto:
 689                 protofamily = AF_INET;
 690                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 691                 case Opt_xprt_udp6:
 692                         protofamily = AF_INET6;
 693                         fallthrough;
 694                 case Opt_xprt_udp:
 695                         ctx->flags &= ~NFS_MOUNT_TCP;
 696                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 697                         break;
 698                 case Opt_xprt_tcp6:
 699                         protofamily = AF_INET6;
 700                         fallthrough;
 701                 case Opt_xprt_tcp:
 702                         ctx->flags |= NFS_MOUNT_TCP;
 703                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 704                         break;
 705                 case Opt_xprt_rdma6:
 706                         protofamily = AF_INET6;
 707                         fallthrough;
 708                 case Opt_xprt_rdma:
 709                         /* vector side protocols to TCP */
 710                         ctx->flags |= NFS_MOUNT_TCP;
 711                         ret = xprt_find_transport_ident(param->string);
 712                         if (ret < 0)
 713                                 goto out_bad_transport;
 714                         ctx->nfs_server.protocol = ret;
 715                         break;
 716                 default:
 717                         goto out_bad_transport;
 718                 }
 719
 720                 ctx->protofamily = protofamily;
 721                 break;
 722
 723         case Opt_mountproto:
 724                 mountfamily = AF_INET;
 725                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 726                 case Opt_xprt_udp6:
 727                         mountfamily = AF_INET6;
 728                         fallthrough;
 729                 case Opt_xprt_udp:
 730                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 731                         break;
 732                 case Opt_xprt_tcp6:
 733                         mountfamily = AF_INET6;
 734                         fallthrough;
 735                 case Opt_xprt_tcp:
 736                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 737                         break;
 738                 case Opt_xprt_rdma: /* not used for side protocols */
 739                 default:
 740                         goto out_bad_transport;
 741                 }
 742                 ctx->mountfamily = mountfamily;
 743                 break;
 744
 745         case Opt_addr:
 746                 len = rpc_pton(fc->net_ns, param->string, param->size,
 747                                &ctx->nfs_server.address,
 748                                sizeof(ctx->nfs_server._address));
 749                 if (len == 0)
 750                         goto out_invalid_address;
 751                 ctx->nfs_server.addrlen = len;
 752                 break;
 753         case Opt_clientaddr:
 754                 kfree(ctx->client_address);
 755                 ctx->client_address = param->string;
 756                 param->string = NULL;
 757                 break;
 758         case Opt_mounthost:
 759                 kfree(ctx->mount_server.hostname);
 760                 ctx->mount_server.hostname = param->string;
 761                 param->string = NULL;
 762                 break;
 763         case Opt_mountaddr:
 764                 len = rpc_pton(fc->net_ns, param->string, param->size,
 765                                &ctx->mount_server.address,
 766                                sizeof(ctx->mount_server._address));
 767                 if (len == 0)
 768                         goto out_invalid_address;
 769                 ctx->mount_server.addrlen = len;
 770                 break;
 771         case Opt_nconnect:
 772                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 773                         goto out_of_bounds;
 774                 ctx->nfs_server.nconnect = result.uint_32;
 775                 break;
 776         case Opt_max_connect:
 777                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
 778                         goto out_of_bounds;
 779                 ctx->nfs_server.max_connect = result.uint_32;
 780                 break;
 781         case Opt_lookupcache:
 782                 switch (result.uint_32) {
 783                 case Opt_lookupcache_all:
 784                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 785                         break;
 786                 case Opt_lookupcache_positive:
 787                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 788                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 789                         break;
 790                 case Opt_lookupcache_none:
 791                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 792                         break;
 793                 default:
 794                         goto out_invalid_value;
 795                 }
 796                 break;
 797         case Opt_local_lock:
 798                 switch (result.uint_32) {
 799                 case Opt_local_lock_all:
 800                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 801                                        NFS_MOUNT_LOCAL_FCNTL);
 802                         break;
 803                 case Opt_local_lock_flock:
 804                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 805                         break;
 806                 case Opt_local_lock_posix:
 807                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 808                         break;
 809                 case Opt_local_lock_none:
 810                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 811                                         NFS_MOUNT_LOCAL_FCNTL);
 812                         break;
 813                 default:
 814                         goto out_invalid_value;
 815                 }
 816                 break;
 817         case Opt_write:
 818                 switch (result.uint_32) {
 819                 case Opt_write_lazy:
 820                         ctx->flags &=
 821                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 822                         break;
 823                 case Opt_write_eager:
 824                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 825                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 826                         break;
 827                 case Opt_write_wait:
 828                         ctx->flags |=
 829                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 830                         break;
 831                 default:
 832                         goto out_invalid_value;
 833                 }
 834                 break;
 835
 836                 /*
 837                  * Special options
 838                  */
 839         case Opt_sloppy:
 840                 ctx->sloppy = true;
 841                 dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
 842                 break;
 843         }
 844
 845         return 0;
 846
 847 out_invalid_value:
 848         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 849 out_invalid_address:
 850         return nfs_invalf(fc, "NFS: Bad IP address specified");
 851 out_of_bounds:
 852         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 853 out_bad_transport:
 854         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 855 }
 856
 857 /*
 858  * Split fc->source into "hostname:export_path".
 859  *
 860  * The leftmost colon demarks the split between the server's hostname
 861  * and the export path.  If the hostname starts with a left square
 862  * bracket, then it may contain colons.
 863  *
 864  * Note: caller frees hostname and export path, even on error.
 865  */
 866 static int nfs_parse_source(struct fs_context *fc,
 867                             size_t maxnamlen, size_t maxpathlen)
 868 {
 869         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 870         const char *dev_name = fc->source;
 871         size_t len;
 872         const char *end;
 873
 874         if (unlikely(!dev_name || !*dev_name)) {
 875                 dfprintk(MOUNT, "NFS: device name not specified\n");
 876                 return -EINVAL;
 877         }
 878
 879         /* Is the host name protected with square brakcets? */
 880         if (*dev_name == '[') {
 881                 end = strchr(++dev_name, ']');
 882                 if (end == NULL || end[1] != ':')
 883                         goto out_bad_devname;
 884
 885                 len = end - dev_name;
 886                 end++;
 887         } else {
 888                 const char *comma;
 889
 890                 end = strchr(dev_name, ':');
 891                 if (end == NULL)
 892                         goto out_bad_devname;
 893                 len = end - dev_name;
 894
 895                 /* kill possible hostname list: not supported */
 896                 comma = memchr(dev_name, ',', len);
 897                 if (comma)
 898                         len = comma - dev_name;
 899         }
 900
 901         if (len > maxnamlen)
 902                 goto out_hostname;
 903
 904         kfree(ctx->nfs_server.hostname);
 905
 906         /* N.B. caller will free nfs_server.hostname in all cases */
 907         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 908         if (!ctx->nfs_server.hostname)
 909                 goto out_nomem;
 910         len = strlen(++end);
 911         if (len > maxpathlen)
 912                 goto out_path;
 913         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
 914         if (!ctx->nfs_server.export_path)
 915                 goto out_nomem;
 916
 917         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
 918         return 0;
 919
 920 out_bad_devname:
 921         return nfs_invalf(fc, "NFS: device name not in host:path format");
 922 out_nomem:
 923         nfs_errorf(fc, "NFS: not enough memory to parse device name");
 924         return -ENOMEM;
 925 out_hostname:
 926         nfs_errorf(fc, "NFS: server hostname too long");
 927         return -ENAMETOOLONG;
 928 out_path:
 929         nfs_errorf(fc, "NFS: export pathname too long");
 930         return -ENAMETOOLONG;
 931 }
 932
 933 static inline bool is_remount_fc(struct fs_context *fc)
 934 {
 935         return fc->root != NULL;
 936 }
 937
 938 /*
 939  * Parse monolithic NFS2/NFS3 mount data
 940  * - fills in the mount root filehandle
 941  *
 942  * For option strings, user space handles the following behaviors:
 943  *
 944  * + DNS: mapping server host name to IP address ("addr=" option)
 945  *
 946  * + failure mode: how to behave if a mount request can't be handled
 947  *   immediately ("fg/bg" option)
 948  *
 949  * + retry: how often to retry a mount request ("retry=" option)
 950  *
 951  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
 952  *   mountproto=tcp after mountproto=udp, and so on
 953  */
 954 static int nfs23_parse_monolithic(struct fs_context *fc,
 955                                   struct nfs_mount_data *data)
 956 {
 957         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 958         struct nfs_fh *mntfh = ctx->mntfh;
 959         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
 960         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
 961         int ret;
 962
 963         if (data == NULL)
 964                 goto out_no_data;
 965
 966         ctx->version = NFS_DEFAULT_VERSION;
 967         switch (data->version) {
 968         case 1:
 969                 data->namlen = 0;
 970                 fallthrough;
 971         case 2:
 972                 data->bsize = 0;
 973                 fallthrough;
 974         case 3:
 975                 if (data->flags & NFS_MOUNT_VER3)
 976                         goto out_no_v3;
 977                 data->root.size = NFS2_FHSIZE;
 978                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
 979                 /* Turn off security negotiation */
 980                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
 981                 fallthrough;
 982         case 4:
 983                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
 984                         goto out_no_sec;
 985                 fallthrough;
 986         case 5:
 987                 memset(data->context, 0, sizeof(data->context));
 988                 fallthrough;
 989         case 6:
 990                 if (data->flags & NFS_MOUNT_VER3) {
 991                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
 992                                 goto out_invalid_fh;
 993                         mntfh->size = data->root.size;
 994                         ctx->version = 3;
 995                 } else {
 996                         mntfh->size = NFS2_FHSIZE;
 997                         ctx->version = 2;
 998                 }
 999
1000
1001                 memcpy(mntfh->data, data->root.data, mntfh->size);
1002                 if (mntfh->size < sizeof(mntfh->data))
1003                         memset(mntfh->data + mntfh->size, 0,
1004                                sizeof(mntfh->data) - mntfh->size);
1005
1006                 /*
1007                  * for proto == XPRT_TRANSPORT_UDP, which is what uses
1008                  * to_exponential, implying shift: limit the shift value
1009                  * to BITS_PER_LONG (majortimeo is unsigned long)
1010                  */
1011                 if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1012                         if (data->retrans >= 64) /* shift value is too large */
1013                                 goto out_invalid_data;
1014
1015                 /*
1016                  * Translate to nfs_fs_context, which nfs_fill_super
1017                  * can deal with.
1018                  */
1019                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
1020                 ctx->flags      |= extra_flags;
1021                 ctx->rsize      = data->rsize;
1022                 ctx->wsize      = data->wsize;
1023                 ctx->timeo      = data->timeo;
1024                 ctx->retrans    = data->retrans;
1025                 ctx->acregmin   = data->acregmin;
1026                 ctx->acregmax   = data->acregmax;
1027                 ctx->acdirmin   = data->acdirmin;
1028                 ctx->acdirmax   = data->acdirmax;
1029                 ctx->need_mount = false;
1030
1031                 memcpy(sap, &data->addr, sizeof(data->addr));
1032                 ctx->nfs_server.addrlen = sizeof(data->addr);
1033                 ctx->nfs_server.port = ntohs(data->addr.sin_port);
1034                 if (sap->sa_family != AF_INET ||
1035                     !nfs_verify_server_address(sap))
1036                         goto out_no_address;
1037
1038                 if (!(data->flags & NFS_MOUNT_TCP))
1039                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1040                 /* N.B. caller will free nfs_server.hostname in all cases */
1041                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1042                 if (!ctx->nfs_server.hostname)
1043                         goto out_nomem;
1044
1045                 ctx->namlen             = data->namlen;
1046                 ctx->bsize              = data->bsize;
1047
1048                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1049                         ctx->selected_flavor = data->pseudoflavor;
1050                 else
1051                         ctx->selected_flavor = RPC_AUTH_UNIX;
1052
1053                 if (!(data->flags & NFS_MOUNT_NONLM))
1054                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1055                                          NFS_MOUNT_LOCAL_FCNTL);
1056                 else
1057                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1058                                         NFS_MOUNT_LOCAL_FCNTL);
1059
1060                 /*
1061                  * The legacy version 6 binary mount data from userspace has a
1062                  * field used only to transport selinux information into the
1063                  * kernel.  To continue to support that functionality we
1064                  * have a touch of selinux knowledge here in the NFS code. The
1065                  * userspace code converted context=blah to just blah so we are
1066                  * converting back to the full string selinux understands.
1067                  */
1068                 if (data->context[0]){
1069 #ifdef CONFIG_SECURITY_SELINUX
1070                         int ret;
1071
1072                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1073                         ret = vfs_parse_fs_string(fc, "context",
1074                                                   data->context, strlen(data->context));
1075                         if (ret < 0)
1076                                 return ret;
1077 #else
1078                         return -EINVAL;
1079 #endif
1080                 }
1081
1082                 break;
1083         default:
1084                 goto generic;
1085         }
1086
1087         ret = nfs_validate_transport_protocol(fc, ctx);
1088         if (ret)
1089                 return ret;
1090
1091         ctx->skip_reconfig_option_check = true;
1092         return 0;
1093
1094 generic:
1095         return generic_parse_monolithic(fc, data);
1096
1097 out_no_data:
1098         if (is_remount_fc(fc)) {
1099                 ctx->skip_reconfig_option_check = true;
1100                 return 0;
1101         }
1102         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1103
1104 out_no_v3:
1105         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1106
1107 out_no_sec:
1108         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1109
1110 out_nomem:
1111         dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
1112         return -ENOMEM;
1113
1114 out_no_address:
1115         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1116
1117 out_invalid_fh:
1118         return nfs_invalf(fc, "NFS: invalid root filehandle");
1119
1120 out_invalid_data:
1121         return nfs_invalf(fc, "NFS: invalid binary mount data");
1122 }
1123
1124 #if IS_ENABLED(CONFIG_NFS_V4)
1125 struct compat_nfs_string {
1126         compat_uint_t len;
1127         compat_uptr_t data;
1128 };
1129
1130 static inline void compat_nfs_string(struct nfs_string *dst,
1131                                      struct compat_nfs_string *src)
1132 {
1133         dst->data = compat_ptr(src->data);
1134         dst->len = src->len;
1135 }
1136
1137 struct compat_nfs4_mount_data_v1 {
1138         compat_int_t version;
1139         compat_int_t flags;
1140         compat_int_t rsize;
1141         compat_int_t wsize;
1142         compat_int_t timeo;
1143         compat_int_t retrans;
1144         compat_int_t acregmin;
1145         compat_int_t acregmax;
1146         compat_int_t acdirmin;
1147         compat_int_t acdirmax;
1148         struct compat_nfs_string client_addr;
1149         struct compat_nfs_string mnt_path;
1150         struct compat_nfs_string hostname;
1151         compat_uint_t host_addrlen;
1152         compat_uptr_t host_addr;
1153         compat_int_t proto;
1154         compat_int_t auth_flavourlen;
1155         compat_uptr_t auth_flavours;
1156 };
1157
1158 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1159 {
1160         struct compat_nfs4_mount_data_v1 *compat =
1161                         (struct compat_nfs4_mount_data_v1 *)data;
1162
1163         /* copy the fields backwards */
1164         data->auth_flavours = compat_ptr(compat->auth_flavours);
1165         data->auth_flavourlen = compat->auth_flavourlen;
1166         data->proto = compat->proto;
1167         data->host_addr = compat_ptr(compat->host_addr);
1168         data->host_addrlen = compat->host_addrlen;
1169         compat_nfs_string(&data->hostname, &compat->hostname);
1170         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1171         compat_nfs_string(&data->client_addr, &compat->client_addr);
1172         data->acdirmax = compat->acdirmax;
1173         data->acdirmin = compat->acdirmin;
1174         data->acregmax = compat->acregmax;
1175         data->acregmin = compat->acregmin;
1176         data->retrans = compat->retrans;
1177         data->timeo = compat->timeo;
1178         data->wsize = compat->wsize;
1179         data->rsize = compat->rsize;
1180         data->flags = compat->flags;
1181         data->version = compat->version;
1182 }
1183
1184 /*
1185  * Validate NFSv4 mount options
1186  */
1187 static int nfs4_parse_monolithic(struct fs_context *fc,
1188                                  struct nfs4_mount_data *data)
1189 {
1190         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1191         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1192         int ret;
1193         char *c;
1194
1195         if (!data) {
1196                 if (is_remount_fc(fc))
1197                         goto done;
1198                 return nfs_invalf(fc,
1199                         "NFS4: mount program didn't pass any mount data");
1200         }
1201
1202         ctx->version = 4;
1203
1204         if (data->version != 1)
1205                 return generic_parse_monolithic(fc, data);
1206
1207         if (in_compat_syscall())
1208                 nfs4_compat_mount_data_conv(data);
1209
1210         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1211                 goto out_no_address;
1212         if (data->host_addrlen == 0)
1213                 goto out_no_address;
1214         ctx->nfs_server.addrlen = data->host_addrlen;
1215         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1216                 return -EFAULT;
1217         if (!nfs_verify_server_address(sap))
1218                 goto out_no_address;
1219         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1220
1221         if (data->auth_flavourlen) {
1222                 rpc_authflavor_t pseudoflavor;
1223
1224                 if (data->auth_flavourlen > 1)
1225                         goto out_inval_auth;
1226                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1227                                    sizeof(pseudoflavor)))
1228                         return -EFAULT;
1229                 ctx->selected_flavor = pseudoflavor;
1230         } else {
1231                 ctx->selected_flavor = RPC_AUTH_UNIX;
1232         }
1233
1234         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1235         if (IS_ERR(c))
1236                 return PTR_ERR(c);
1237         ctx->nfs_server.hostname = c;
1238
1239         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1240         if (IS_ERR(c))
1241                 return PTR_ERR(c);
1242         ctx->nfs_server.export_path = c;
1243         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1244
1245         c = strndup_user(data->client_addr.data, 16);
1246         if (IS_ERR(c))
1247                 return PTR_ERR(c);
1248         ctx->client_address = c;
1249
1250         /*
1251          * Translate to nfs_fs_context, which nfs_fill_super
1252          * can deal with.
1253          */
1254
1255         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1256         ctx->rsize      = data->rsize;
1257         ctx->wsize      = data->wsize;
1258         ctx->timeo      = data->timeo;
1259         ctx->retrans    = data->retrans;
1260         ctx->acregmin   = data->acregmin;
1261         ctx->acregmax   = data->acregmax;
1262         ctx->acdirmin   = data->acdirmin;
1263         ctx->acdirmax   = data->acdirmax;
1264         ctx->nfs_server.protocol = data->proto;
1265         ret = nfs_validate_transport_protocol(fc, ctx);
1266         if (ret)
1267                 return ret;
1268 done:
1269         ctx->skip_reconfig_option_check = true;
1270         return 0;
1271
1272 out_inval_auth:
1273         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1274                       data->auth_flavourlen);
1275
1276 out_no_address:
1277         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1278 }
1279 #endif
1280
1281 /*
1282  * Parse a monolithic block of data from sys_mount().
1283  */
1284 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1285                                            void *data)
1286 {
1287         if (fc->fs_type == &nfs_fs_type)
1288                 return nfs23_parse_monolithic(fc, data);
1289
1290 #if IS_ENABLED(CONFIG_NFS_V4)
1291         if (fc->fs_type == &nfs4_fs_type)
1292                 return nfs4_parse_monolithic(fc, data);
1293 #endif
1294
1295         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1296 }
1297
1298 /*
1299  * Validate the preparsed information in the config.
1300  */
1301 static int nfs_fs_context_validate(struct fs_context *fc)
1302 {
1303         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1304         struct nfs_subversion *nfs_mod;
1305         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1306         int max_namelen = PAGE_SIZE;
1307         int max_pathlen = NFS_MAXPATHLEN;
1308         int port = 0;
1309         int ret;
1310
1311         if (!fc->source)
1312                 goto out_no_device_name;
1313
1314         /* Check for sanity first. */
1315         if (ctx->minorversion && ctx->version != 4)
1316                 goto out_minorversion_mismatch;
1317
1318         if (ctx->options & NFS_OPTION_MIGRATION &&
1319             (ctx->version != 4 || ctx->minorversion != 0))
1320                 goto out_migration_misuse;
1321
1322         /* Verify that any proto=/mountproto= options match the address
1323          * families in the addr=/mountaddr= options.
1324          */
1325         if (ctx->protofamily != AF_UNSPEC &&
1326             ctx->protofamily != ctx->nfs_server.address.sa_family)
1327                 goto out_proto_mismatch;
1328
1329         if (ctx->mountfamily != AF_UNSPEC) {
1330                 if (ctx->mount_server.addrlen) {
1331                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1332                                 goto out_mountproto_mismatch;
1333                 } else {
1334                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1335                                 goto out_mountproto_mismatch;
1336                 }
1337         }
1338
1339         if (!nfs_verify_server_address(sap))
1340                 goto out_no_address;
1341
1342         ret = nfs_validate_transport_protocol(fc, ctx);
1343         if (ret)
1344                 return ret;
1345
1346         if (ctx->version == 4) {
1347                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1348                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1349                                 port = NFS_RDMA_PORT;
1350                         else
1351                                 port = NFS_PORT;
1352                         max_namelen = NFS4_MAXNAMLEN;
1353                         max_pathlen = NFS4_MAXPATHLEN;
1354                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1355                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1356                                         NFS_MOUNT_LOCAL_FCNTL);
1357                 } else {
1358                         goto out_v4_not_compiled;
1359                 }
1360         } else {
1361                 nfs_set_mount_transport_protocol(ctx);
1362                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1363                         port = NFS_RDMA_PORT;
1364         }
1365
1366         nfs_set_port(sap, &ctx->nfs_server.port, port);
1367
1368         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1369         if (ret < 0)
1370                 return ret;
1371
1372         /* Load the NFS protocol module if we haven't done so yet */
1373         if (!ctx->nfs_mod) {
1374                 nfs_mod = get_nfs_version(ctx->version);
1375                 if (IS_ERR(nfs_mod)) {
1376                         ret = PTR_ERR(nfs_mod);
1377                         goto out_version_unavailable;
1378                 }
1379                 ctx->nfs_mod = nfs_mod;
1380         }
1381
1382         /* Ensure the filesystem context has the correct fs_type */
1383         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1384                 module_put(fc->fs_type->owner);
1385                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1386                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1387         }
1388         return 0;
1389
1390 out_no_device_name:
1391         return nfs_invalf(fc, "NFS: Device name not specified");
1392 out_v4_not_compiled:
1393         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1394         return -EPROTONOSUPPORT;
1395 out_no_address:
1396         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1397 out_mountproto_mismatch:
1398         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1399 out_proto_mismatch:
1400         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1401 out_minorversion_mismatch:
1402         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1403                           ctx->version, ctx->minorversion);
1404 out_migration_misuse:
1405         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1406 out_version_unavailable:
1407         nfs_errorf(fc, "NFS: Version unavailable");
1408         return ret;
1409 }
1410
1411 /*
1412  * Create an NFS superblock by the appropriate method.
1413  */
1414 static int nfs_get_tree(struct fs_context *fc)
1415 {
1416         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1417         int err = nfs_fs_context_validate(fc);
1418
1419         if (err)
1420                 return err;
1421         if (!ctx->internal)
1422                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1423         else
1424                 return nfs_get_tree_common(fc);
1425 }
1426
1427 /*
1428  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1429  * it can't deal with resource pointers in the filesystem context, so we have
1430  * to do that.  We need to clear pointers, copy data or get extra refs as
1431  * appropriate.
1432  */
1433 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1434 {
1435         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1436
1437         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1438         if (!ctx)
1439                 return -ENOMEM;
1440
1441         ctx->mntfh = nfs_alloc_fhandle();
1442         if (!ctx->mntfh) {
1443                 kfree(ctx);
1444                 return -ENOMEM;
1445         }
1446         nfs_copy_fh(ctx->mntfh, src->mntfh);
1447
1448         __module_get(ctx->nfs_mod->owner);
1449         ctx->client_address             = NULL;
1450         ctx->mount_server.hostname      = NULL;
1451         ctx->nfs_server.export_path     = NULL;
1452         ctx->nfs_server.hostname        = NULL;
1453         ctx->fscache_uniq               = NULL;
1454         ctx->clone_data.fattr           = NULL;
1455         fc->fs_private = ctx;
1456         return 0;
1457 }
1458
1459 static void nfs_fs_context_free(struct fs_context *fc)
1460 {
1461         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1462
1463         if (ctx) {
1464                 if (ctx->server)
1465                         nfs_free_server(ctx->server);
1466                 if (ctx->nfs_mod)
1467                         put_nfs_version(ctx->nfs_mod);
1468                 kfree(ctx->client_address);
1469                 kfree(ctx->mount_server.hostname);
1470                 kfree(ctx->nfs_server.export_path);
1471                 kfree(ctx->nfs_server.hostname);
1472                 kfree(ctx->fscache_uniq);
1473                 nfs_free_fhandle(ctx->mntfh);
1474                 nfs_free_fattr(ctx->clone_data.fattr);
1475                 kfree(ctx);
1476         }
1477 }
1478
1479 static const struct fs_context_operations nfs_fs_context_ops = {
1480         .free                   = nfs_fs_context_free,
1481         .dup                    = nfs_fs_context_dup,
1482         .parse_param            = nfs_fs_context_parse_param,
1483         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1484         .get_tree               = nfs_get_tree,
1485         .reconfigure            = nfs_reconfigure,
1486 };
1487
1488 /*
1489  * Prepare superblock configuration.  We use the namespaces attached to the
1490  * context.  This may be the current process's namespaces, or it may be a
1491  * container's namespaces.
1492  */
1493 static int nfs_init_fs_context(struct fs_context *fc)
1494 {
1495         struct nfs_fs_context *ctx;
1496
1497         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1498         if (unlikely(!ctx))
1499                 return -ENOMEM;
1500
1501         ctx->mntfh = nfs_alloc_fhandle();
1502         if (unlikely(!ctx->mntfh)) {
1503                 kfree(ctx);
1504                 return -ENOMEM;
1505         }
1506
1507         ctx->protofamily        = AF_UNSPEC;
1508         ctx->mountfamily        = AF_UNSPEC;
1509         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1510
1511         if (fc->root) {
1512                 /* reconfigure, start with the current config */
1513                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1514                 struct net *net = nfss->nfs_client->cl_net;
1515
1516                 ctx->flags              = nfss->flags;
1517                 ctx->rsize              = nfss->rsize;
1518                 ctx->wsize              = nfss->wsize;
1519                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1520                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1521                 ctx->acregmin           = nfss->acregmin / HZ;
1522                 ctx->acregmax           = nfss->acregmax / HZ;
1523                 ctx->acdirmin           = nfss->acdirmin / HZ;
1524                 ctx->acdirmax           = nfss->acdirmax / HZ;
1525                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1526                 ctx->nfs_server.port    = nfss->port;
1527                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1528                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1529                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1530
1531                 memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
1532                         ctx->nfs_server.addrlen);
1533
1534                 if (fc->net_ns != net) {
1535                         put_net(fc->net_ns);
1536                         fc->net_ns = get_net(net);
1537                 }
1538
1539                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1540                 __module_get(ctx->nfs_mod->owner);
1541         } else {
1542                 /* defaults */
1543                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1544                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1545                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1546                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1547                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1548                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1549                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1550                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1551                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1552                 ctx->minorversion       = 0;
1553                 ctx->need_mount         = true;
1554
1555                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1556         }
1557         fc->fs_private = ctx;
1558         fc->ops = &nfs_fs_context_ops;
1559         return 0;
1560 }
1561
1562 struct file_system_type nfs_fs_type = {
1563         .owner                  = THIS_MODULE,
1564         .name                   = "nfs",
1565         .init_fs_context        = nfs_init_fs_context,
1566         .parameters             = nfs_fs_parameters,
1567         .kill_sb                = nfs_kill_super,
1568         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1569 };
1570 MODULE_ALIAS_FS("nfs");
1571 EXPORT_SYMBOL_GPL(nfs_fs_type);
1572
1573 #if IS_ENABLED(CONFIG_NFS_V4)
1574 struct file_system_type nfs4_fs_type = {
1575         .owner                  = THIS_MODULE,
1576         .name                   = "nfs4",
1577         .init_fs_context        = nfs_init_fs_context,
1578         .parameters             = nfs_fs_parameters,
1579         .kill_sb                = nfs_kill_super,
1580         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1581 };
1582 MODULE_ALIAS_FS("nfs4");
1583 MODULE_ALIAS("nfs4");
1584 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1585 #endif /* CONFIG_NFS_V4 */