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 <[email protected]>
  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_trunkdiscovery,
  84         Opt_udp,
  85         Opt_v,
  86         Opt_vers,
  87         Opt_wsize,
  88         Opt_write,
  89 };
  90
  91 enum {
  92         Opt_local_lock_all,
  93         Opt_local_lock_flock,
  94         Opt_local_lock_none,
  95         Opt_local_lock_posix,
  96 };
  97
  98 static const struct constant_table nfs_param_enums_local_lock[] = {
  99         { "all",                Opt_local_lock_all },
 100         { "flock",      Opt_local_lock_flock },
 101         { "posix",      Opt_local_lock_posix },
 102         { "none",               Opt_local_lock_none },
 103         {}
 104 };
 105
 106 enum {
 107         Opt_lookupcache_all,
 108         Opt_lookupcache_none,
 109         Opt_lookupcache_positive,
 110 };
 111
 112 static const struct constant_table nfs_param_enums_lookupcache[] = {
 113         { "all",                Opt_lookupcache_all },
 114         { "none",               Opt_lookupcache_none },
 115         { "pos",                Opt_lookupcache_positive },
 116         { "positive",           Opt_lookupcache_positive },
 117         {}
 118 };
 119
 120 enum {
 121         Opt_write_lazy,
 122         Opt_write_eager,
 123         Opt_write_wait,
 124 };
 125
 126 static const struct constant_table nfs_param_enums_write[] = {
 127         { "lazy",               Opt_write_lazy },
 128         { "eager",              Opt_write_eager },
 129         { "wait",               Opt_write_wait },
 130         {}
 131 };
 132
 133 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 134         fsparam_flag_no("ac",           Opt_ac),
 135         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 136         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 137         fsparam_flag_no("acl",          Opt_acl),
 138         fsparam_u32   ("acregmax",      Opt_acregmax),
 139         fsparam_u32   ("acregmin",      Opt_acregmin),
 140         fsparam_u32   ("actimeo",       Opt_actimeo),
 141         fsparam_string("addr",          Opt_addr),
 142         fsparam_flag  ("bg",            Opt_bg),
 143         fsparam_u32   ("bsize",         Opt_bsize),
 144         fsparam_string("clientaddr",    Opt_clientaddr),
 145         fsparam_flag_no("cto",          Opt_cto),
 146         fsparam_flag  ("fg",            Opt_fg),
 147         fsparam_flag_no("fsc",          Opt_fscache_flag),
 148         fsparam_string("fsc",           Opt_fscache),
 149         fsparam_flag  ("hard",          Opt_hard),
 150         __fsparam(NULL, "intr",         Opt_intr,
 151                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 152         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 153         fsparam_flag_no("lock",         Opt_lock),
 154         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 155         fsparam_flag_no("migration",    Opt_migration),
 156         fsparam_u32   ("minorversion",  Opt_minorversion),
 157         fsparam_string("mountaddr",     Opt_mountaddr),
 158         fsparam_string("mounthost",     Opt_mounthost),
 159         fsparam_u32   ("mountport",     Opt_mountport),
 160         fsparam_string("mountproto",    Opt_mountproto),
 161         fsparam_u32   ("mountvers",     Opt_mountvers),
 162         fsparam_u32   ("namlen",        Opt_namelen),
 163         fsparam_u32   ("nconnect",      Opt_nconnect),
 164         fsparam_u32   ("max_connect",   Opt_max_connect),
 165         fsparam_string("nfsvers",       Opt_vers),
 166         fsparam_u32   ("port",          Opt_port),
 167         fsparam_flag_no("posix",        Opt_posix),
 168         fsparam_string("proto",         Opt_proto),
 169         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 170         fsparam_flag  ("rdma",          Opt_rdma),
 171         fsparam_flag_no("resvport",     Opt_resvport),
 172         fsparam_u32   ("retrans",       Opt_retrans),
 173         fsparam_string("retry",         Opt_retry),
 174         fsparam_u32   ("rsize",         Opt_rsize),
 175         fsparam_string("sec",           Opt_sec),
 176         fsparam_flag_no("sharecache",   Opt_sharecache),
 177         fsparam_flag  ("sloppy",        Opt_sloppy),
 178         fsparam_flag  ("soft",          Opt_soft),
 179         fsparam_flag  ("softerr",       Opt_softerr),
 180         fsparam_flag  ("softreval",     Opt_softreval),
 181         fsparam_string("source",        Opt_source),
 182         fsparam_flag  ("tcp",           Opt_tcp),
 183         fsparam_u32   ("timeo",         Opt_timeo),
 184         fsparam_flag_no("trunkdiscovery", Opt_trunkdiscovery),
 185         fsparam_flag  ("udp",           Opt_udp),
 186         fsparam_flag  ("v2",            Opt_v),
 187         fsparam_flag  ("v3",            Opt_v),
 188         fsparam_flag  ("v4",            Opt_v),
 189         fsparam_flag  ("v4.0",          Opt_v),
 190         fsparam_flag  ("v4.1",          Opt_v),
 191         fsparam_flag  ("v4.2",          Opt_v),
 192         fsparam_string("vers",          Opt_vers),
 193         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 194         fsparam_u32   ("wsize",         Opt_wsize),
 195         {}
 196 };
 197
 198 enum {
 199         Opt_vers_2,
 200         Opt_vers_3,
 201         Opt_vers_4,
 202         Opt_vers_4_0,
 203         Opt_vers_4_1,
 204         Opt_vers_4_2,
 205 };
 206
 207 static const struct constant_table nfs_vers_tokens[] = {
 208         { "2",          Opt_vers_2 },
 209         { "3",          Opt_vers_3 },
 210         { "4",          Opt_vers_4 },
 211         { "4.0",        Opt_vers_4_0 },
 212         { "4.1",        Opt_vers_4_1 },
 213         { "4.2",        Opt_vers_4_2 },
 214         {}
 215 };
 216
 217 enum {
 218         Opt_xprt_rdma,
 219         Opt_xprt_rdma6,
 220         Opt_xprt_tcp,
 221         Opt_xprt_tcp6,
 222         Opt_xprt_udp,
 223         Opt_xprt_udp6,
 224         nr__Opt_xprt
 225 };
 226
 227 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 228         { "rdma",       Opt_xprt_rdma },
 229         { "rdma6",      Opt_xprt_rdma6 },
 230         { "tcp",        Opt_xprt_tcp },
 231         { "tcp6",       Opt_xprt_tcp6 },
 232         { "udp",        Opt_xprt_udp },
 233         { "udp6",       Opt_xprt_udp6 },
 234         {}
 235 };
 236
 237 enum {
 238         Opt_sec_krb5,
 239         Opt_sec_krb5i,
 240         Opt_sec_krb5p,
 241         Opt_sec_lkey,
 242         Opt_sec_lkeyi,
 243         Opt_sec_lkeyp,
 244         Opt_sec_none,
 245         Opt_sec_spkm,
 246         Opt_sec_spkmi,
 247         Opt_sec_spkmp,
 248         Opt_sec_sys,
 249         nr__Opt_sec
 250 };
 251
 252 static const struct constant_table nfs_secflavor_tokens[] = {
 253         { "krb5",       Opt_sec_krb5 },
 254         { "krb5i",      Opt_sec_krb5i },
 255         { "krb5p",      Opt_sec_krb5p },
 256         { "lkey",       Opt_sec_lkey },
 257         { "lkeyi",      Opt_sec_lkeyi },
 258         { "lkeyp",      Opt_sec_lkeyp },
 259         { "none",       Opt_sec_none },
 260         { "null",       Opt_sec_none },
 261         { "spkm3",      Opt_sec_spkm },
 262         { "spkm3i",     Opt_sec_spkmi },
 263         { "spkm3p",     Opt_sec_spkmp },
 264         { "sys",        Opt_sec_sys },
 265         {}
 266 };
 267
 268 /*
 269  * Sanity-check a server address provided by the mount command.
 270  *
 271  * Address family must be initialized, and address must not be
 272  * the ANY address for that family.
 273  */
 274 static int nfs_verify_server_address(struct sockaddr *addr)
 275 {
 276         switch (addr->sa_family) {
 277         case AF_INET: {
 278                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 279                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 280         }
 281         case AF_INET6: {
 282                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 283                 return !ipv6_addr_any(sa);
 284         }
 285         }
 286
 287         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 288         return 0;
 289 }
 290
 291 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
 292 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 293 {
 294         return true;
 295 }
 296 #else
 297 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 298 {
 299         if (ctx->version == 4)
 300                 return true;
 301         return false;
 302 }
 303 #endif
 304
 305 /*
 306  * Sanity check the NFS transport protocol.
 307  */
 308 static int nfs_validate_transport_protocol(struct fs_context *fc,
 309                                            struct nfs_fs_context *ctx)
 310 {
 311         switch (ctx->nfs_server.protocol) {
 312         case XPRT_TRANSPORT_UDP:
 313                 if (nfs_server_transport_udp_invalid(ctx))
 314                         goto out_invalid_transport_udp;
 315                 break;
 316         case XPRT_TRANSPORT_TCP:
 317         case XPRT_TRANSPORT_RDMA:
 318                 break;
 319         default:
 320                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 321         }
 322         return 0;
 323 out_invalid_transport_udp:
 324         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
 325 }
 326
 327 /*
 328  * For text based NFSv2/v3 mounts, the mount protocol transport default
 329  * settings should depend upon the specified NFS transport.
 330  */
 331 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 332 {
 333         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 334             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 335                         return;
 336         switch (ctx->nfs_server.protocol) {
 337         case XPRT_TRANSPORT_UDP:
 338                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 339                 break;
 340         case XPRT_TRANSPORT_TCP:
 341         case XPRT_TRANSPORT_RDMA:
 342                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 343         }
 344 }
 345
 346 /*
 347  * Add 'flavor' to 'auth_info' if not already present.
 348  * Returns true if 'flavor' ends up in the list, false otherwise
 349  */
 350 static int nfs_auth_info_add(struct fs_context *fc,
 351                              struct nfs_auth_info *auth_info,
 352                              rpc_authflavor_t flavor)
 353 {
 354         unsigned int i;
 355         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 356
 357         /* make sure this flavor isn't already in the list */
 358         for (i = 0; i < auth_info->flavor_len; i++) {
 359                 if (flavor == auth_info->flavors[i])
 360                         return 0;
 361         }
 362
 363         if (auth_info->flavor_len + 1 >= max_flavor_len)
 364                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 365
 366         auth_info->flavors[auth_info->flavor_len++] = flavor;
 367         return 0;
 368 }
 369
 370 /*
 371  * Parse the value of the 'sec=' option.
 372  */
 373 static int nfs_parse_security_flavors(struct fs_context *fc,
 374                                       struct fs_parameter *param)
 375 {
 376         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 377         rpc_authflavor_t pseudoflavor;
 378         char *string = param->string, *p;
 379         int ret;
 380
 381         dfprintk(MOUNT, "NFS: parsing %s=%s option\n", param->key, param->string);
 382
 383         while ((p = strsep(&string, ":")) != NULL) {
 384                 if (!*p)
 385                         continue;
 386                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 387                 case Opt_sec_none:
 388                         pseudoflavor = RPC_AUTH_NULL;
 389                         break;
 390                 case Opt_sec_sys:
 391                         pseudoflavor = RPC_AUTH_UNIX;
 392                         break;
 393                 case Opt_sec_krb5:
 394                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 395                         break;
 396                 case Opt_sec_krb5i:
 397                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 398                         break;
 399                 case Opt_sec_krb5p:
 400                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 401                         break;
 402                 case Opt_sec_lkey:
 403                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 404                         break;
 405                 case Opt_sec_lkeyi:
 406                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 407                         break;
 408                 case Opt_sec_lkeyp:
 409                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 410                         break;
 411                 case Opt_sec_spkm:
 412                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 413                         break;
 414                 case Opt_sec_spkmi:
 415                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 416                         break;
 417                 case Opt_sec_spkmp:
 418                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 419                         break;
 420                 default:
 421                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 422                 }
 423
 424                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 425                 if (ret < 0)
 426                         return ret;
 427         }
 428
 429         return 0;
 430 }
 431
 432 static int nfs_parse_version_string(struct fs_context *fc,
 433                                     const char *string)
 434 {
 435         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 436
 437         ctx->flags &= ~NFS_MOUNT_VER3;
 438         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 439         case Opt_vers_2:
 440                 ctx->version = 2;
 441                 break;
 442         case Opt_vers_3:
 443                 ctx->flags |= NFS_MOUNT_VER3;
 444                 ctx->version = 3;
 445                 break;
 446         case Opt_vers_4:
 447                 /* Backward compatibility option. In future,
 448                  * the mount program should always supply
 449                  * a NFSv4 minor version number.
 450                  */
 451                 ctx->version = 4;
 452                 break;
 453         case Opt_vers_4_0:
 454                 ctx->version = 4;
 455                 ctx->minorversion = 0;
 456                 break;
 457         case Opt_vers_4_1:
 458                 ctx->version = 4;
 459                 ctx->minorversion = 1;
 460                 break;
 461         case Opt_vers_4_2:
 462                 ctx->version = 4;
 463                 ctx->minorversion = 2;
 464                 break;
 465         default:
 466                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 467         }
 468         return 0;
 469 }
 470
 471 /*
 472  * Parse a single mount parameter.
 473  */
 474 static int nfs_fs_context_parse_param(struct fs_context *fc,
 475                                       struct fs_parameter *param)
 476 {
 477         struct fs_parse_result result;
 478         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 479         unsigned short protofamily, mountfamily;
 480         unsigned int len;
 481         int ret, opt;
 482
 483         dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", param->key);
 484
 485         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 486         if (opt < 0)
 487                 return ctx->sloppy ? 1 : opt;
 488
 489         if (fc->security)
 490                 ctx->has_sec_mnt_opts = 1;
 491
 492         switch (opt) {
 493         case Opt_source:
 494                 if (fc->source)
 495                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 496                 fc->source = param->string;
 497                 param->string = NULL;
 498                 break;
 499
 500                 /*
 501                  * boolean options:  foo/nofoo
 502                  */
 503         case Opt_soft:
 504                 ctx->flags |= NFS_MOUNT_SOFT;
 505                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 506                 break;
 507         case Opt_softerr:
 508                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 509                 ctx->flags &= ~NFS_MOUNT_SOFT;
 510                 break;
 511         case Opt_hard:
 512                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 513                                 NFS_MOUNT_SOFTERR |
 514                                 NFS_MOUNT_SOFTREVAL);
 515                 break;
 516         case Opt_softreval:
 517                 if (result.negated)
 518                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 519                 else
 520                         ctx->flags &= NFS_MOUNT_SOFTREVAL;
 521                 break;
 522         case Opt_posix:
 523                 if (result.negated)
 524                         ctx->flags &= ~NFS_MOUNT_POSIX;
 525                 else
 526                         ctx->flags |= NFS_MOUNT_POSIX;
 527                 break;
 528         case Opt_cto:
 529                 if (result.negated)
 530                         ctx->flags |= NFS_MOUNT_NOCTO;
 531                 else
 532                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 533                 break;
 534         case Opt_trunkdiscovery:
 535                 if (result.negated)
 536                         ctx->flags &= ~NFS_MOUNT_TRUNK_DISCOVERY;
 537                 else
 538                         ctx->flags |= NFS_MOUNT_TRUNK_DISCOVERY;
 539                 break;
 540         case Opt_ac:
 541                 if (result.negated)
 542                         ctx->flags |= NFS_MOUNT_NOAC;
 543                 else
 544                         ctx->flags &= ~NFS_MOUNT_NOAC;
 545                 break;
 546         case Opt_lock:
 547                 if (result.negated) {
 548                         ctx->flags |= NFS_MOUNT_NONLM;
 549                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 550                 } else {
 551                         ctx->flags &= ~NFS_MOUNT_NONLM;
 552                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 553                 }
 554                 break;
 555         case Opt_udp:
 556                 ctx->flags &= ~NFS_MOUNT_TCP;
 557                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 558                 break;
 559         case Opt_tcp:
 560         case Opt_rdma:
 561                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 562                 ret = xprt_find_transport_ident(param->key);
 563                 if (ret < 0)
 564                         goto out_bad_transport;
 565                 ctx->nfs_server.protocol = ret;
 566                 break;
 567         case Opt_acl:
 568                 if (result.negated)
 569                         ctx->flags |= NFS_MOUNT_NOACL;
 570                 else
 571                         ctx->flags &= ~NFS_MOUNT_NOACL;
 572                 break;
 573         case Opt_rdirplus:
 574                 if (result.negated)
 575                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 576                 else
 577                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 578                 break;
 579         case Opt_sharecache:
 580                 if (result.negated)
 581                         ctx->flags |= NFS_MOUNT_UNSHARED;
 582                 else
 583                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 584                 break;
 585         case Opt_resvport:
 586                 if (result.negated)
 587                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 588                 else
 589                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 590                 break;
 591         case Opt_fscache_flag:
 592                 if (result.negated)
 593                         ctx->options &= ~NFS_OPTION_FSCACHE;
 594                 else
 595                         ctx->options |= NFS_OPTION_FSCACHE;
 596                 kfree(ctx->fscache_uniq);
 597                 ctx->fscache_uniq = NULL;
 598                 break;
 599         case Opt_fscache:
 600                 ctx->options |= NFS_OPTION_FSCACHE;
 601                 kfree(ctx->fscache_uniq);
 602                 ctx->fscache_uniq = param->string;
 603                 param->string = NULL;
 604                 break;
 605         case Opt_migration:
 606                 if (result.negated)
 607                         ctx->options &= ~NFS_OPTION_MIGRATION;
 608                 else
 609                         ctx->options |= NFS_OPTION_MIGRATION;
 610                 break;
 611
 612                 /*
 613                  * options that take numeric values
 614                  */
 615         case Opt_port:
 616                 if (result.uint_32 > USHRT_MAX)
 617                         goto out_of_bounds;
 618                 ctx->nfs_server.port = result.uint_32;
 619                 break;
 620         case Opt_rsize:
 621                 ctx->rsize = result.uint_32;
 622                 break;
 623         case Opt_wsize:
 624                 ctx->wsize = result.uint_32;
 625                 break;
 626         case Opt_bsize:
 627                 ctx->bsize = result.uint_32;
 628                 break;
 629         case Opt_timeo:
 630                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 631                         goto out_of_bounds;
 632                 ctx->timeo = result.uint_32;
 633                 break;
 634         case Opt_retrans:
 635                 if (result.uint_32 > INT_MAX)
 636                         goto out_of_bounds;
 637                 ctx->retrans = result.uint_32;
 638                 break;
 639         case Opt_acregmin:
 640                 ctx->acregmin = result.uint_32;
 641                 break;
 642         case Opt_acregmax:
 643                 ctx->acregmax = result.uint_32;
 644                 break;
 645         case Opt_acdirmin:
 646                 ctx->acdirmin = result.uint_32;
 647                 break;
 648         case Opt_acdirmax:
 649                 ctx->acdirmax = result.uint_32;
 650                 break;
 651         case Opt_actimeo:
 652                 ctx->acregmin = result.uint_32;
 653                 ctx->acregmax = result.uint_32;
 654                 ctx->acdirmin = result.uint_32;
 655                 ctx->acdirmax = result.uint_32;
 656                 break;
 657         case Opt_namelen:
 658                 ctx->namlen = result.uint_32;
 659                 break;
 660         case Opt_mountport:
 661                 if (result.uint_32 > USHRT_MAX)
 662                         goto out_of_bounds;
 663                 ctx->mount_server.port = result.uint_32;
 664                 break;
 665         case Opt_mountvers:
 666                 if (result.uint_32 < NFS_MNT_VERSION ||
 667                     result.uint_32 > NFS_MNT3_VERSION)
 668                         goto out_of_bounds;
 669                 ctx->mount_server.version = result.uint_32;
 670                 break;
 671         case Opt_minorversion:
 672                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 673                         goto out_of_bounds;
 674                 ctx->minorversion = result.uint_32;
 675                 break;
 676
 677                 /*
 678                  * options that take text values
 679                  */
 680         case Opt_v:
 681                 ret = nfs_parse_version_string(fc, param->key + 1);
 682                 if (ret < 0)
 683                         return ret;
 684                 break;
 685         case Opt_vers:
 686                 ret = nfs_parse_version_string(fc, param->string);
 687                 if (ret < 0)
 688                         return ret;
 689                 break;
 690         case Opt_sec:
 691                 ret = nfs_parse_security_flavors(fc, param);
 692                 if (ret < 0)
 693                         return ret;
 694                 break;
 695
 696         case Opt_proto:
 697                 protofamily = AF_INET;
 698                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 699                 case Opt_xprt_udp6:
 700                         protofamily = AF_INET6;
 701                         fallthrough;
 702                 case Opt_xprt_udp:
 703                         ctx->flags &= ~NFS_MOUNT_TCP;
 704                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 705                         break;
 706                 case Opt_xprt_tcp6:
 707                         protofamily = AF_INET6;
 708                         fallthrough;
 709                 case Opt_xprt_tcp:
 710                         ctx->flags |= NFS_MOUNT_TCP;
 711                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 712                         break;
 713                 case Opt_xprt_rdma6:
 714                         protofamily = AF_INET6;
 715                         fallthrough;
 716                 case Opt_xprt_rdma:
 717                         /* vector side protocols to TCP */
 718                         ctx->flags |= NFS_MOUNT_TCP;
 719                         ret = xprt_find_transport_ident(param->string);
 720                         if (ret < 0)
 721                                 goto out_bad_transport;
 722                         ctx->nfs_server.protocol = ret;
 723                         break;
 724                 default:
 725                         goto out_bad_transport;
 726                 }
 727
 728                 ctx->protofamily = protofamily;
 729                 break;
 730
 731         case Opt_mountproto:
 732                 mountfamily = AF_INET;
 733                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 734                 case Opt_xprt_udp6:
 735                         mountfamily = AF_INET6;
 736                         fallthrough;
 737                 case Opt_xprt_udp:
 738                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 739                         break;
 740                 case Opt_xprt_tcp6:
 741                         mountfamily = AF_INET6;
 742                         fallthrough;
 743                 case Opt_xprt_tcp:
 744                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 745                         break;
 746                 case Opt_xprt_rdma: /* not used for side protocols */
 747                 default:
 748                         goto out_bad_transport;
 749                 }
 750                 ctx->mountfamily = mountfamily;
 751                 break;
 752
 753         case Opt_addr:
 754                 len = rpc_pton(fc->net_ns, param->string, param->size,
 755                                &ctx->nfs_server.address,
 756                                sizeof(ctx->nfs_server._address));
 757                 if (len == 0)
 758                         goto out_invalid_address;
 759                 ctx->nfs_server.addrlen = len;
 760                 break;
 761         case Opt_clientaddr:
 762                 kfree(ctx->client_address);
 763                 ctx->client_address = param->string;
 764                 param->string = NULL;
 765                 break;
 766         case Opt_mounthost:
 767                 kfree(ctx->mount_server.hostname);
 768                 ctx->mount_server.hostname = param->string;
 769                 param->string = NULL;
 770                 break;
 771         case Opt_mountaddr:
 772                 len = rpc_pton(fc->net_ns, param->string, param->size,
 773                                &ctx->mount_server.address,
 774                                sizeof(ctx->mount_server._address));
 775                 if (len == 0)
 776                         goto out_invalid_address;
 777                 ctx->mount_server.addrlen = len;
 778                 break;
 779         case Opt_nconnect:
 780                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 781                         goto out_of_bounds;
 782                 ctx->nfs_server.nconnect = result.uint_32;
 783                 break;
 784         case Opt_max_connect:
 785                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
 786                         goto out_of_bounds;
 787                 ctx->nfs_server.max_connect = result.uint_32;
 788                 break;
 789         case Opt_lookupcache:
 790                 switch (result.uint_32) {
 791                 case Opt_lookupcache_all:
 792                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 793                         break;
 794                 case Opt_lookupcache_positive:
 795                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 796                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 797                         break;
 798                 case Opt_lookupcache_none:
 799                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 800                         break;
 801                 default:
 802                         goto out_invalid_value;
 803                 }
 804                 break;
 805         case Opt_local_lock:
 806                 switch (result.uint_32) {
 807                 case Opt_local_lock_all:
 808                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 809                                        NFS_MOUNT_LOCAL_FCNTL);
 810                         break;
 811                 case Opt_local_lock_flock:
 812                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 813                         break;
 814                 case Opt_local_lock_posix:
 815                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 816                         break;
 817                 case Opt_local_lock_none:
 818                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 819                                         NFS_MOUNT_LOCAL_FCNTL);
 820                         break;
 821                 default:
 822                         goto out_invalid_value;
 823                 }
 824                 break;
 825         case Opt_write:
 826                 switch (result.uint_32) {
 827                 case Opt_write_lazy:
 828                         ctx->flags &=
 829                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 830                         break;
 831                 case Opt_write_eager:
 832                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 833                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 834                         break;
 835                 case Opt_write_wait:
 836                         ctx->flags |=
 837                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 838                         break;
 839                 default:
 840                         goto out_invalid_value;
 841                 }
 842                 break;
 843
 844                 /*
 845                  * Special options
 846                  */
 847         case Opt_sloppy:
 848                 ctx->sloppy = true;
 849                 dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
 850                 break;
 851         }
 852
 853         return 0;
 854
 855 out_invalid_value:
 856         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 857 out_invalid_address:
 858         return nfs_invalf(fc, "NFS: Bad IP address specified");
 859 out_of_bounds:
 860         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 861 out_bad_transport:
 862         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 863 }
 864
 865 /*
 866  * Split fc->source into "hostname:export_path".
 867  *
 868  * The leftmost colon demarks the split between the server's hostname
 869  * and the export path.  If the hostname starts with a left square
 870  * bracket, then it may contain colons.
 871  *
 872  * Note: caller frees hostname and export path, even on error.
 873  */
 874 static int nfs_parse_source(struct fs_context *fc,
 875                             size_t maxnamlen, size_t maxpathlen)
 876 {
 877         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 878         const char *dev_name = fc->source;
 879         size_t len;
 880         const char *end;
 881
 882         if (unlikely(!dev_name || !*dev_name)) {
 883                 dfprintk(MOUNT, "NFS: device name not specified\n");
 884                 return -EINVAL;
 885         }
 886
 887         /* Is the host name protected with square brakcets? */
 888         if (*dev_name == '[') {
 889                 end = strchr(++dev_name, ']');
 890                 if (end == NULL || end[1] != ':')
 891                         goto out_bad_devname;
 892
 893                 len = end - dev_name;
 894                 end++;
 895         } else {
 896                 const char *comma;
 897
 898                 end = strchr(dev_name, ':');
 899                 if (end == NULL)
 900                         goto out_bad_devname;
 901                 len = end - dev_name;
 902
 903                 /* kill possible hostname list: not supported */
 904                 comma = memchr(dev_name, ',', len);
 905                 if (comma)
 906                         len = comma - dev_name;
 907         }
 908
 909         if (len > maxnamlen)
 910                 goto out_hostname;
 911
 912         kfree(ctx->nfs_server.hostname);
 913
 914         /* N.B. caller will free nfs_server.hostname in all cases */
 915         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 916         if (!ctx->nfs_server.hostname)
 917                 goto out_nomem;
 918         len = strlen(++end);
 919         if (len > maxpathlen)
 920                 goto out_path;
 921         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
 922         if (!ctx->nfs_server.export_path)
 923                 goto out_nomem;
 924
 925         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
 926         return 0;
 927
 928 out_bad_devname:
 929         return nfs_invalf(fc, "NFS: device name not in host:path format");
 930 out_nomem:
 931         nfs_errorf(fc, "NFS: not enough memory to parse device name");
 932         return -ENOMEM;
 933 out_hostname:
 934         nfs_errorf(fc, "NFS: server hostname too long");
 935         return -ENAMETOOLONG;
 936 out_path:
 937         nfs_errorf(fc, "NFS: export pathname too long");
 938         return -ENAMETOOLONG;
 939 }
 940
 941 static inline bool is_remount_fc(struct fs_context *fc)
 942 {
 943         return fc->root != NULL;
 944 }
 945
 946 /*
 947  * Parse monolithic NFS2/NFS3 mount data
 948  * - fills in the mount root filehandle
 949  *
 950  * For option strings, user space handles the following behaviors:
 951  *
 952  * + DNS: mapping server host name to IP address ("addr=" option)
 953  *
 954  * + failure mode: how to behave if a mount request can't be handled
 955  *   immediately ("fg/bg" option)
 956  *
 957  * + retry: how often to retry a mount request ("retry=" option)
 958  *
 959  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
 960  *   mountproto=tcp after mountproto=udp, and so on
 961  */
 962 static int nfs23_parse_monolithic(struct fs_context *fc,
 963                                   struct nfs_mount_data *data)
 964 {
 965         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 966         struct nfs_fh *mntfh = ctx->mntfh;
 967         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
 968         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
 969         int ret;
 970
 971         if (data == NULL)
 972                 goto out_no_data;
 973
 974         ctx->version = NFS_DEFAULT_VERSION;
 975         switch (data->version) {
 976         case 1:
 977                 data->namlen = 0;
 978                 fallthrough;
 979         case 2:
 980                 data->bsize = 0;
 981                 fallthrough;
 982         case 3:
 983                 if (data->flags & NFS_MOUNT_VER3)
 984                         goto out_no_v3;
 985                 data->root.size = NFS2_FHSIZE;
 986                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
 987                 /* Turn off security negotiation */
 988                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
 989                 fallthrough;
 990         case 4:
 991                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
 992                         goto out_no_sec;
 993                 fallthrough;
 994         case 5:
 995                 memset(data->context, 0, sizeof(data->context));
 996                 fallthrough;
 997         case 6:
 998                 if (data->flags & NFS_MOUNT_VER3) {
 999                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1000                                 goto out_invalid_fh;
1001                         mntfh->size = data->root.size;
1002                         ctx->version = 3;
1003                 } else {
1004                         mntfh->size = NFS2_FHSIZE;
1005                         ctx->version = 2;
1006                 }
1007
1008
1009                 memcpy(mntfh->data, data->root.data, mntfh->size);
1010                 if (mntfh->size < sizeof(mntfh->data))
1011                         memset(mntfh->data + mntfh->size, 0,
1012                                sizeof(mntfh->data) - mntfh->size);
1013
1014                 /*
1015                  * for proto == XPRT_TRANSPORT_UDP, which is what uses
1016                  * to_exponential, implying shift: limit the shift value
1017                  * to BITS_PER_LONG (majortimeo is unsigned long)
1018                  */
1019                 if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1020                         if (data->retrans >= 64) /* shift value is too large */
1021                                 goto out_invalid_data;
1022
1023                 /*
1024                  * Translate to nfs_fs_context, which nfs_fill_super
1025                  * can deal with.
1026                  */
1027                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
1028                 ctx->flags      |= extra_flags;
1029                 ctx->rsize      = data->rsize;
1030                 ctx->wsize      = data->wsize;
1031                 ctx->timeo      = data->timeo;
1032                 ctx->retrans    = data->retrans;
1033                 ctx->acregmin   = data->acregmin;
1034                 ctx->acregmax   = data->acregmax;
1035                 ctx->acdirmin   = data->acdirmin;
1036                 ctx->acdirmax   = data->acdirmax;
1037                 ctx->need_mount = false;
1038
1039                 memcpy(sap, &data->addr, sizeof(data->addr));
1040                 ctx->nfs_server.addrlen = sizeof(data->addr);
1041                 ctx->nfs_server.port = ntohs(data->addr.sin_port);
1042                 if (sap->sa_family != AF_INET ||
1043                     !nfs_verify_server_address(sap))
1044                         goto out_no_address;
1045
1046                 if (!(data->flags & NFS_MOUNT_TCP))
1047                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1048                 /* N.B. caller will free nfs_server.hostname in all cases */
1049                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1050                 if (!ctx->nfs_server.hostname)
1051                         goto out_nomem;
1052
1053                 ctx->namlen             = data->namlen;
1054                 ctx->bsize              = data->bsize;
1055
1056                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1057                         ctx->selected_flavor = data->pseudoflavor;
1058                 else
1059                         ctx->selected_flavor = RPC_AUTH_UNIX;
1060
1061                 if (!(data->flags & NFS_MOUNT_NONLM))
1062                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1063                                          NFS_MOUNT_LOCAL_FCNTL);
1064                 else
1065                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1066                                         NFS_MOUNT_LOCAL_FCNTL);
1067
1068                 /*
1069                  * The legacy version 6 binary mount data from userspace has a
1070                  * field used only to transport selinux information into the
1071                  * kernel.  To continue to support that functionality we
1072                  * have a touch of selinux knowledge here in the NFS code. The
1073                  * userspace code converted context=blah to just blah so we are
1074                  * converting back to the full string selinux understands.
1075                  */
1076                 if (data->context[0]){
1077 #ifdef CONFIG_SECURITY_SELINUX
1078                         int ret;
1079
1080                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1081                         ret = vfs_parse_fs_string(fc, "context",
1082                                                   data->context, strlen(data->context));
1083                         if (ret < 0)
1084                                 return ret;
1085 #else
1086                         return -EINVAL;
1087 #endif
1088                 }
1089
1090                 break;
1091         default:
1092                 goto generic;
1093         }
1094
1095         ret = nfs_validate_transport_protocol(fc, ctx);
1096         if (ret)
1097                 return ret;
1098
1099         ctx->skip_reconfig_option_check = true;
1100         return 0;
1101
1102 generic:
1103         return generic_parse_monolithic(fc, data);
1104
1105 out_no_data:
1106         if (is_remount_fc(fc)) {
1107                 ctx->skip_reconfig_option_check = true;
1108                 return 0;
1109         }
1110         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1111
1112 out_no_v3:
1113         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1114
1115 out_no_sec:
1116         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1117
1118 out_nomem:
1119         dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
1120         return -ENOMEM;
1121
1122 out_no_address:
1123         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1124
1125 out_invalid_fh:
1126         return nfs_invalf(fc, "NFS: invalid root filehandle");
1127
1128 out_invalid_data:
1129         return nfs_invalf(fc, "NFS: invalid binary mount data");
1130 }
1131
1132 #if IS_ENABLED(CONFIG_NFS_V4)
1133 struct compat_nfs_string {
1134         compat_uint_t len;
1135         compat_uptr_t data;
1136 };
1137
1138 static inline void compat_nfs_string(struct nfs_string *dst,
1139                                      struct compat_nfs_string *src)
1140 {
1141         dst->data = compat_ptr(src->data);
1142         dst->len = src->len;
1143 }
1144
1145 struct compat_nfs4_mount_data_v1 {
1146         compat_int_t version;
1147         compat_int_t flags;
1148         compat_int_t rsize;
1149         compat_int_t wsize;
1150         compat_int_t timeo;
1151         compat_int_t retrans;
1152         compat_int_t acregmin;
1153         compat_int_t acregmax;
1154         compat_int_t acdirmin;
1155         compat_int_t acdirmax;
1156         struct compat_nfs_string client_addr;
1157         struct compat_nfs_string mnt_path;
1158         struct compat_nfs_string hostname;
1159         compat_uint_t host_addrlen;
1160         compat_uptr_t host_addr;
1161         compat_int_t proto;
1162         compat_int_t auth_flavourlen;
1163         compat_uptr_t auth_flavours;
1164 };
1165
1166 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1167 {
1168         struct compat_nfs4_mount_data_v1 *compat =
1169                         (struct compat_nfs4_mount_data_v1 *)data;
1170
1171         /* copy the fields backwards */
1172         data->auth_flavours = compat_ptr(compat->auth_flavours);
1173         data->auth_flavourlen = compat->auth_flavourlen;
1174         data->proto = compat->proto;
1175         data->host_addr = compat_ptr(compat->host_addr);
1176         data->host_addrlen = compat->host_addrlen;
1177         compat_nfs_string(&data->hostname, &compat->hostname);
1178         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1179         compat_nfs_string(&data->client_addr, &compat->client_addr);
1180         data->acdirmax = compat->acdirmax;
1181         data->acdirmin = compat->acdirmin;
1182         data->acregmax = compat->acregmax;
1183         data->acregmin = compat->acregmin;
1184         data->retrans = compat->retrans;
1185         data->timeo = compat->timeo;
1186         data->wsize = compat->wsize;
1187         data->rsize = compat->rsize;
1188         data->flags = compat->flags;
1189         data->version = compat->version;
1190 }
1191
1192 /*
1193  * Validate NFSv4 mount options
1194  */
1195 static int nfs4_parse_monolithic(struct fs_context *fc,
1196                                  struct nfs4_mount_data *data)
1197 {
1198         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1199         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1200         int ret;
1201         char *c;
1202
1203         if (!data) {
1204                 if (is_remount_fc(fc))
1205                         goto done;
1206                 return nfs_invalf(fc,
1207                         "NFS4: mount program didn't pass any mount data");
1208         }
1209
1210         ctx->version = 4;
1211
1212         if (data->version != 1)
1213                 return generic_parse_monolithic(fc, data);
1214
1215         if (in_compat_syscall())
1216                 nfs4_compat_mount_data_conv(data);
1217
1218         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1219                 goto out_no_address;
1220         if (data->host_addrlen == 0)
1221                 goto out_no_address;
1222         ctx->nfs_server.addrlen = data->host_addrlen;
1223         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1224                 return -EFAULT;
1225         if (!nfs_verify_server_address(sap))
1226                 goto out_no_address;
1227         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1228
1229         if (data->auth_flavourlen) {
1230                 rpc_authflavor_t pseudoflavor;
1231
1232                 if (data->auth_flavourlen > 1)
1233                         goto out_inval_auth;
1234                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1235                                    sizeof(pseudoflavor)))
1236                         return -EFAULT;
1237                 ctx->selected_flavor = pseudoflavor;
1238         } else {
1239                 ctx->selected_flavor = RPC_AUTH_UNIX;
1240         }
1241
1242         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1243         if (IS_ERR(c))
1244                 return PTR_ERR(c);
1245         ctx->nfs_server.hostname = c;
1246
1247         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1248         if (IS_ERR(c))
1249                 return PTR_ERR(c);
1250         ctx->nfs_server.export_path = c;
1251         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1252
1253         c = strndup_user(data->client_addr.data, 16);
1254         if (IS_ERR(c))
1255                 return PTR_ERR(c);
1256         ctx->client_address = c;
1257
1258         /*
1259          * Translate to nfs_fs_context, which nfs_fill_super
1260          * can deal with.
1261          */
1262
1263         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1264         ctx->rsize      = data->rsize;
1265         ctx->wsize      = data->wsize;
1266         ctx->timeo      = data->timeo;
1267         ctx->retrans    = data->retrans;
1268         ctx->acregmin   = data->acregmin;
1269         ctx->acregmax   = data->acregmax;
1270         ctx->acdirmin   = data->acdirmin;
1271         ctx->acdirmax   = data->acdirmax;
1272         ctx->nfs_server.protocol = data->proto;
1273         ret = nfs_validate_transport_protocol(fc, ctx);
1274         if (ret)
1275                 return ret;
1276 done:
1277         ctx->skip_reconfig_option_check = true;
1278         return 0;
1279
1280 out_inval_auth:
1281         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1282                       data->auth_flavourlen);
1283
1284 out_no_address:
1285         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1286 }
1287 #endif
1288
1289 /*
1290  * Parse a monolithic block of data from sys_mount().
1291  */
1292 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1293                                            void *data)
1294 {
1295         if (fc->fs_type == &nfs_fs_type)
1296                 return nfs23_parse_monolithic(fc, data);
1297
1298 #if IS_ENABLED(CONFIG_NFS_V4)
1299         if (fc->fs_type == &nfs4_fs_type)
1300                 return nfs4_parse_monolithic(fc, data);
1301 #endif
1302
1303         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1304 }
1305
1306 /*
1307  * Validate the preparsed information in the config.
1308  */
1309 static int nfs_fs_context_validate(struct fs_context *fc)
1310 {
1311         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1312         struct nfs_subversion *nfs_mod;
1313         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1314         int max_namelen = PAGE_SIZE;
1315         int max_pathlen = NFS_MAXPATHLEN;
1316         int port = 0;
1317         int ret;
1318
1319         if (!fc->source)
1320                 goto out_no_device_name;
1321
1322         /* Check for sanity first. */
1323         if (ctx->minorversion && ctx->version != 4)
1324                 goto out_minorversion_mismatch;
1325
1326         if (ctx->options & NFS_OPTION_MIGRATION &&
1327             (ctx->version != 4 || ctx->minorversion != 0))
1328                 goto out_migration_misuse;
1329
1330         /* Verify that any proto=/mountproto= options match the address
1331          * families in the addr=/mountaddr= options.
1332          */
1333         if (ctx->protofamily != AF_UNSPEC &&
1334             ctx->protofamily != ctx->nfs_server.address.sa_family)
1335                 goto out_proto_mismatch;
1336
1337         if (ctx->mountfamily != AF_UNSPEC) {
1338                 if (ctx->mount_server.addrlen) {
1339                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1340                                 goto out_mountproto_mismatch;
1341                 } else {
1342                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1343                                 goto out_mountproto_mismatch;
1344                 }
1345         }
1346
1347         if (!nfs_verify_server_address(sap))
1348                 goto out_no_address;
1349
1350         ret = nfs_validate_transport_protocol(fc, ctx);
1351         if (ret)
1352                 return ret;
1353
1354         if (ctx->version == 4) {
1355                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1356                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1357                                 port = NFS_RDMA_PORT;
1358                         else
1359                                 port = NFS_PORT;
1360                         max_namelen = NFS4_MAXNAMLEN;
1361                         max_pathlen = NFS4_MAXPATHLEN;
1362                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1363                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1364                                         NFS_MOUNT_LOCAL_FCNTL);
1365                 } else {
1366                         goto out_v4_not_compiled;
1367                 }
1368         } else {
1369                 nfs_set_mount_transport_protocol(ctx);
1370                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1371                         port = NFS_RDMA_PORT;
1372         }
1373
1374         nfs_set_port(sap, &ctx->nfs_server.port, port);
1375
1376         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1377         if (ret < 0)
1378                 return ret;
1379
1380         /* Load the NFS protocol module if we haven't done so yet */
1381         if (!ctx->nfs_mod) {
1382                 nfs_mod = get_nfs_version(ctx->version);
1383                 if (IS_ERR(nfs_mod)) {
1384                         ret = PTR_ERR(nfs_mod);
1385                         goto out_version_unavailable;
1386                 }
1387                 ctx->nfs_mod = nfs_mod;
1388         }
1389
1390         /* Ensure the filesystem context has the correct fs_type */
1391         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1392                 module_put(fc->fs_type->owner);
1393                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1394                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1395         }
1396         return 0;
1397
1398 out_no_device_name:
1399         return nfs_invalf(fc, "NFS: Device name not specified");
1400 out_v4_not_compiled:
1401         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1402         return -EPROTONOSUPPORT;
1403 out_no_address:
1404         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1405 out_mountproto_mismatch:
1406         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1407 out_proto_mismatch:
1408         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1409 out_minorversion_mismatch:
1410         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1411                           ctx->version, ctx->minorversion);
1412 out_migration_misuse:
1413         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1414 out_version_unavailable:
1415         nfs_errorf(fc, "NFS: Version unavailable");
1416         return ret;
1417 }
1418
1419 /*
1420  * Create an NFS superblock by the appropriate method.
1421  */
1422 static int nfs_get_tree(struct fs_context *fc)
1423 {
1424         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1425         int err = nfs_fs_context_validate(fc);
1426
1427         if (err)
1428                 return err;
1429         if (!ctx->internal)
1430                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1431         else
1432                 return nfs_get_tree_common(fc);
1433 }
1434
1435 /*
1436  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1437  * it can't deal with resource pointers in the filesystem context, so we have
1438  * to do that.  We need to clear pointers, copy data or get extra refs as
1439  * appropriate.
1440  */
1441 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1442 {
1443         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1444
1445         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1446         if (!ctx)
1447                 return -ENOMEM;
1448
1449         ctx->mntfh = nfs_alloc_fhandle();
1450         if (!ctx->mntfh) {
1451                 kfree(ctx);
1452                 return -ENOMEM;
1453         }
1454         nfs_copy_fh(ctx->mntfh, src->mntfh);
1455
1456         __module_get(ctx->nfs_mod->owner);
1457         ctx->client_address             = NULL;
1458         ctx->mount_server.hostname      = NULL;
1459         ctx->nfs_server.export_path     = NULL;
1460         ctx->nfs_server.hostname        = NULL;
1461         ctx->fscache_uniq               = NULL;
1462         ctx->clone_data.fattr           = NULL;
1463         fc->fs_private = ctx;
1464         return 0;
1465 }
1466
1467 static void nfs_fs_context_free(struct fs_context *fc)
1468 {
1469         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1470
1471         if (ctx) {
1472                 if (ctx->server)
1473                         nfs_free_server(ctx->server);
1474                 if (ctx->nfs_mod)
1475                         put_nfs_version(ctx->nfs_mod);
1476                 kfree(ctx->client_address);
1477                 kfree(ctx->mount_server.hostname);
1478                 kfree(ctx->nfs_server.export_path);
1479                 kfree(ctx->nfs_server.hostname);
1480                 kfree(ctx->fscache_uniq);
1481                 nfs_free_fhandle(ctx->mntfh);
1482                 nfs_free_fattr(ctx->clone_data.fattr);
1483                 kfree(ctx);
1484         }
1485 }
1486
1487 static const struct fs_context_operations nfs_fs_context_ops = {
1488         .free                   = nfs_fs_context_free,
1489         .dup                    = nfs_fs_context_dup,
1490         .parse_param            = nfs_fs_context_parse_param,
1491         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1492         .get_tree               = nfs_get_tree,
1493         .reconfigure            = nfs_reconfigure,
1494 };
1495
1496 /*
1497  * Prepare superblock configuration.  We use the namespaces attached to the
1498  * context.  This may be the current process's namespaces, or it may be a
1499  * container's namespaces.
1500  */
1501 static int nfs_init_fs_context(struct fs_context *fc)
1502 {
1503         struct nfs_fs_context *ctx;
1504
1505         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1506         if (unlikely(!ctx))
1507                 return -ENOMEM;
1508
1509         ctx->mntfh = nfs_alloc_fhandle();
1510         if (unlikely(!ctx->mntfh)) {
1511                 kfree(ctx);
1512                 return -ENOMEM;
1513         }
1514
1515         ctx->protofamily        = AF_UNSPEC;
1516         ctx->mountfamily        = AF_UNSPEC;
1517         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1518
1519         if (fc->root) {
1520                 /* reconfigure, start with the current config */
1521                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1522                 struct net *net = nfss->nfs_client->cl_net;
1523
1524                 ctx->flags              = nfss->flags;
1525                 ctx->rsize              = nfss->rsize;
1526                 ctx->wsize              = nfss->wsize;
1527                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1528                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1529                 ctx->acregmin           = nfss->acregmin / HZ;
1530                 ctx->acregmax           = nfss->acregmax / HZ;
1531                 ctx->acdirmin           = nfss->acdirmin / HZ;
1532                 ctx->acdirmax           = nfss->acdirmax / HZ;
1533                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1534                 ctx->nfs_server.port    = nfss->port;
1535                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1536                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1537                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1538
1539                 memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
1540                         ctx->nfs_server.addrlen);
1541
1542                 if (fc->net_ns != net) {
1543                         put_net(fc->net_ns);
1544                         fc->net_ns = get_net(net);
1545                 }
1546
1547                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1548                 __module_get(ctx->nfs_mod->owner);
1549         } else {
1550                 /* defaults */
1551                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1552                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1553                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1554                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1555                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1556                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1557                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1558                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1559                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1560                 ctx->minorversion       = 0;
1561                 ctx->need_mount         = true;
1562
1563                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1564         }
1565         fc->fs_private = ctx;
1566         fc->ops = &nfs_fs_context_ops;
1567         return 0;
1568 }
1569
1570 struct file_system_type nfs_fs_type = {
1571         .owner                  = THIS_MODULE,
1572         .name                   = "nfs",
1573         .init_fs_context        = nfs_init_fs_context,
1574         .parameters             = nfs_fs_parameters,
1575         .kill_sb                = nfs_kill_super,
1576         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1577 };
1578 MODULE_ALIAS_FS("nfs");
1579 EXPORT_SYMBOL_GPL(nfs_fs_type);
1580
1581 #if IS_ENABLED(CONFIG_NFS_V4)
1582 struct file_system_type nfs4_fs_type = {
1583         .owner                  = THIS_MODULE,
1584         .name                   = "nfs4",
1585         .init_fs_context        = nfs_init_fs_context,
1586         .parameters             = nfs_fs_parameters,
1587         .kill_sb                = nfs_kill_super,
1588         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1589 };
1590 MODULE_ALIAS_FS("nfs4");
1591 MODULE_ALIAS("nfs4");
1592 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1593 #endif /* CONFIG_NFS_V4 */