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
  22 #include <net/handshake.h>
  23
  24 #include "nfs.h"
  25 #include "internal.h"
  26
  27 #include "nfstrace.h"
  28
  29 #define NFSDBG_FACILITY         NFSDBG_MOUNT
  30
  31 #if IS_ENABLED(CONFIG_NFS_V3)
  32 #define NFS_DEFAULT_VERSION 3
  33 #else
  34 #define NFS_DEFAULT_VERSION 2
  35 #endif
  36
  37 #define NFS_MAX_CONNECTIONS 16
  38
  39 enum nfs_param {
  40         Opt_ac,
  41         Opt_acdirmax,
  42         Opt_acdirmin,
  43         Opt_acl,
  44         Opt_acregmax,
  45         Opt_acregmin,
  46         Opt_actimeo,
  47         Opt_addr,
  48         Opt_bg,
  49         Opt_bsize,
  50         Opt_clientaddr,
  51         Opt_cto,
  52         Opt_fg,
  53         Opt_fscache,
  54         Opt_fscache_flag,
  55         Opt_hard,
  56         Opt_intr,
  57         Opt_local_lock,
  58         Opt_lock,
  59         Opt_lookupcache,
  60         Opt_migration,
  61         Opt_minorversion,
  62         Opt_mountaddr,
  63         Opt_mounthost,
  64         Opt_mountport,
  65         Opt_mountproto,
  66         Opt_mountvers,
  67         Opt_namelen,
  68         Opt_nconnect,
  69         Opt_max_connect,
  70         Opt_port,
  71         Opt_posix,
  72         Opt_proto,
  73         Opt_rdirplus,
  74         Opt_rdma,
  75         Opt_resvport,
  76         Opt_retrans,
  77         Opt_retry,
  78         Opt_rsize,
  79         Opt_sec,
  80         Opt_sharecache,
  81         Opt_sloppy,
  82         Opt_soft,
  83         Opt_softerr,
  84         Opt_softreval,
  85         Opt_source,
  86         Opt_tcp,
  87         Opt_timeo,
  88         Opt_trunkdiscovery,
  89         Opt_udp,
  90         Opt_v,
  91         Opt_vers,
  92         Opt_wsize,
  93         Opt_write,
  94         Opt_xprtsec,
  95 };
  96
  97 enum {
  98         Opt_local_lock_all,
  99         Opt_local_lock_flock,
 100         Opt_local_lock_none,
 101         Opt_local_lock_posix,
 102 };
 103
 104 static const struct constant_table nfs_param_enums_local_lock[] = {
 105         { "all",                Opt_local_lock_all },
 106         { "flock",      Opt_local_lock_flock },
 107         { "posix",      Opt_local_lock_posix },
 108         { "none",               Opt_local_lock_none },
 109         {}
 110 };
 111
 112 enum {
 113         Opt_lookupcache_all,
 114         Opt_lookupcache_none,
 115         Opt_lookupcache_positive,
 116 };
 117
 118 static const struct constant_table nfs_param_enums_lookupcache[] = {
 119         { "all",                Opt_lookupcache_all },
 120         { "none",               Opt_lookupcache_none },
 121         { "pos",                Opt_lookupcache_positive },
 122         { "positive",           Opt_lookupcache_positive },
 123         {}
 124 };
 125
 126 enum {
 127         Opt_write_lazy,
 128         Opt_write_eager,
 129         Opt_write_wait,
 130 };
 131
 132 static const struct constant_table nfs_param_enums_write[] = {
 133         { "lazy",               Opt_write_lazy },
 134         { "eager",              Opt_write_eager },
 135         { "wait",               Opt_write_wait },
 136         {}
 137 };
 138
 139 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 140         fsparam_flag_no("ac",           Opt_ac),
 141         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 142         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 143         fsparam_flag_no("acl",          Opt_acl),
 144         fsparam_u32   ("acregmax",      Opt_acregmax),
 145         fsparam_u32   ("acregmin",      Opt_acregmin),
 146         fsparam_u32   ("actimeo",       Opt_actimeo),
 147         fsparam_string("addr",          Opt_addr),
 148         fsparam_flag  ("bg",            Opt_bg),
 149         fsparam_u32   ("bsize",         Opt_bsize),
 150         fsparam_string("clientaddr",    Opt_clientaddr),
 151         fsparam_flag_no("cto",          Opt_cto),
 152         fsparam_flag  ("fg",            Opt_fg),
 153         fsparam_flag_no("fsc",          Opt_fscache_flag),
 154         fsparam_string("fsc",           Opt_fscache),
 155         fsparam_flag  ("hard",          Opt_hard),
 156         __fsparam(NULL, "intr",         Opt_intr,
 157                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 158         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 159         fsparam_flag_no("lock",         Opt_lock),
 160         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 161         fsparam_flag_no("migration",    Opt_migration),
 162         fsparam_u32   ("minorversion",  Opt_minorversion),
 163         fsparam_string("mountaddr",     Opt_mountaddr),
 164         fsparam_string("mounthost",     Opt_mounthost),
 165         fsparam_u32   ("mountport",     Opt_mountport),
 166         fsparam_string("mountproto",    Opt_mountproto),
 167         fsparam_u32   ("mountvers",     Opt_mountvers),
 168         fsparam_u32   ("namlen",        Opt_namelen),
 169         fsparam_u32   ("nconnect",      Opt_nconnect),
 170         fsparam_u32   ("max_connect",   Opt_max_connect),
 171         fsparam_string("nfsvers",       Opt_vers),
 172         fsparam_u32   ("port",          Opt_port),
 173         fsparam_flag_no("posix",        Opt_posix),
 174         fsparam_string("proto",         Opt_proto),
 175         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 176         fsparam_flag  ("rdma",          Opt_rdma),
 177         fsparam_flag_no("resvport",     Opt_resvport),
 178         fsparam_u32   ("retrans",       Opt_retrans),
 179         fsparam_string("retry",         Opt_retry),
 180         fsparam_u32   ("rsize",         Opt_rsize),
 181         fsparam_string("sec",           Opt_sec),
 182         fsparam_flag_no("sharecache",   Opt_sharecache),
 183         fsparam_flag  ("sloppy",        Opt_sloppy),
 184         fsparam_flag  ("soft",          Opt_soft),
 185         fsparam_flag  ("softerr",       Opt_softerr),
 186         fsparam_flag  ("softreval",     Opt_softreval),
 187         fsparam_string("source",        Opt_source),
 188         fsparam_flag  ("tcp",           Opt_tcp),
 189         fsparam_u32   ("timeo",         Opt_timeo),
 190         fsparam_flag_no("trunkdiscovery", Opt_trunkdiscovery),
 191         fsparam_flag  ("udp",           Opt_udp),
 192         fsparam_flag  ("v2",            Opt_v),
 193         fsparam_flag  ("v3",            Opt_v),
 194         fsparam_flag  ("v4",            Opt_v),
 195         fsparam_flag  ("v4.0",          Opt_v),
 196         fsparam_flag  ("v4.1",          Opt_v),
 197         fsparam_flag  ("v4.2",          Opt_v),
 198         fsparam_string("vers",          Opt_vers),
 199         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 200         fsparam_u32   ("wsize",         Opt_wsize),
 201         fsparam_string("xprtsec",       Opt_xprtsec),
 202         {}
 203 };
 204
 205 enum {
 206         Opt_vers_2,
 207         Opt_vers_3,
 208         Opt_vers_4,
 209         Opt_vers_4_0,
 210         Opt_vers_4_1,
 211         Opt_vers_4_2,
 212 };
 213
 214 static const struct constant_table nfs_vers_tokens[] = {
 215         { "2",          Opt_vers_2 },
 216         { "3",          Opt_vers_3 },
 217         { "4",          Opt_vers_4 },
 218         { "4.0",        Opt_vers_4_0 },
 219         { "4.1",        Opt_vers_4_1 },
 220         { "4.2",        Opt_vers_4_2 },
 221         {}
 222 };
 223
 224 enum {
 225         Opt_xprt_rdma,
 226         Opt_xprt_rdma6,
 227         Opt_xprt_tcp,
 228         Opt_xprt_tcp6,
 229         Opt_xprt_udp,
 230         Opt_xprt_udp6,
 231         nr__Opt_xprt
 232 };
 233
 234 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 235         { "rdma",       Opt_xprt_rdma },
 236         { "rdma6",      Opt_xprt_rdma6 },
 237         { "tcp",        Opt_xprt_tcp },
 238         { "tcp6",       Opt_xprt_tcp6 },
 239         { "udp",        Opt_xprt_udp },
 240         { "udp6",       Opt_xprt_udp6 },
 241         {}
 242 };
 243
 244 enum {
 245         Opt_sec_krb5,
 246         Opt_sec_krb5i,
 247         Opt_sec_krb5p,
 248         Opt_sec_lkey,
 249         Opt_sec_lkeyi,
 250         Opt_sec_lkeyp,
 251         Opt_sec_none,
 252         Opt_sec_spkm,
 253         Opt_sec_spkmi,
 254         Opt_sec_spkmp,
 255         Opt_sec_sys,
 256         nr__Opt_sec
 257 };
 258
 259 static const struct constant_table nfs_secflavor_tokens[] = {
 260         { "krb5",       Opt_sec_krb5 },
 261         { "krb5i",      Opt_sec_krb5i },
 262         { "krb5p",      Opt_sec_krb5p },
 263         { "lkey",       Opt_sec_lkey },
 264         { "lkeyi",      Opt_sec_lkeyi },
 265         { "lkeyp",      Opt_sec_lkeyp },
 266         { "none",       Opt_sec_none },
 267         { "null",       Opt_sec_none },
 268         { "spkm3",      Opt_sec_spkm },
 269         { "spkm3i",     Opt_sec_spkmi },
 270         { "spkm3p",     Opt_sec_spkmp },
 271         { "sys",        Opt_sec_sys },
 272         {}
 273 };
 274
 275 enum {
 276         Opt_xprtsec_none,
 277         Opt_xprtsec_tls,
 278         Opt_xprtsec_mtls,
 279         nr__Opt_xprtsec
 280 };
 281
 282 static const struct constant_table nfs_xprtsec_policies[] = {
 283         { "none",       Opt_xprtsec_none },
 284         { "tls",        Opt_xprtsec_tls },
 285         { "mtls",       Opt_xprtsec_mtls },
 286         {}
 287 };
 288
 289 /*
 290  * Sanity-check a server address provided by the mount command.
 291  *
 292  * Address family must be initialized, and address must not be
 293  * the ANY address for that family.
 294  */
 295 static int nfs_verify_server_address(struct sockaddr_storage *addr)
 296 {
 297         switch (addr->ss_family) {
 298         case AF_INET: {
 299                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 300                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 301         }
 302         case AF_INET6: {
 303                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 304                 return !ipv6_addr_any(sa);
 305         }
 306         }
 307
 308         return 0;
 309 }
 310
 311 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
 312 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 313 {
 314         return true;
 315 }
 316 #else
 317 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 318 {
 319         if (ctx->version == 4)
 320                 return true;
 321         return false;
 322 }
 323 #endif
 324
 325 /*
 326  * Sanity check the NFS transport protocol.
 327  */
 328 static int nfs_validate_transport_protocol(struct fs_context *fc,
 329                                            struct nfs_fs_context *ctx)
 330 {
 331         switch (ctx->nfs_server.protocol) {
 332         case XPRT_TRANSPORT_UDP:
 333                 if (nfs_server_transport_udp_invalid(ctx))
 334                         goto out_invalid_transport_udp;
 335                 break;
 336         case XPRT_TRANSPORT_TCP:
 337         case XPRT_TRANSPORT_RDMA:
 338                 break;
 339         default:
 340                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 341         }
 342
 343         if (ctx->xprtsec.policy != RPC_XPRTSEC_NONE)
 344                 switch (ctx->nfs_server.protocol) {
 345                 case XPRT_TRANSPORT_TCP:
 346                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP_TLS;
 347                         break;
 348                 default:
 349                         goto out_invalid_xprtsec_policy;
 350         }
 351
 352         return 0;
 353 out_invalid_transport_udp:
 354         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
 355 out_invalid_xprtsec_policy:
 356         return nfs_invalf(fc, "NFS: Transport does not support xprtsec");
 357 }
 358
 359 /*
 360  * For text based NFSv2/v3 mounts, the mount protocol transport default
 361  * settings should depend upon the specified NFS transport.
 362  */
 363 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 364 {
 365         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 366             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 367                         return;
 368         switch (ctx->nfs_server.protocol) {
 369         case XPRT_TRANSPORT_UDP:
 370                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 371                 break;
 372         case XPRT_TRANSPORT_TCP:
 373         case XPRT_TRANSPORT_RDMA:
 374                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 375         }
 376 }
 377
 378 /*
 379  * Add 'flavor' to 'auth_info' if not already present.
 380  * Returns true if 'flavor' ends up in the list, false otherwise
 381  */
 382 static int nfs_auth_info_add(struct fs_context *fc,
 383                              struct nfs_auth_info *auth_info,
 384                              rpc_authflavor_t flavor)
 385 {
 386         unsigned int i;
 387         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 388
 389         /* make sure this flavor isn't already in the list */
 390         for (i = 0; i < auth_info->flavor_len; i++) {
 391                 if (flavor == auth_info->flavors[i])
 392                         return 0;
 393         }
 394
 395         if (auth_info->flavor_len + 1 >= max_flavor_len)
 396                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 397
 398         auth_info->flavors[auth_info->flavor_len++] = flavor;
 399         return 0;
 400 }
 401
 402 /*
 403  * Parse the value of the 'sec=' option.
 404  */
 405 static int nfs_parse_security_flavors(struct fs_context *fc,
 406                                       struct fs_parameter *param)
 407 {
 408         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 409         rpc_authflavor_t pseudoflavor;
 410         char *string = param->string, *p;
 411         int ret;
 412
 413         trace_nfs_mount_assign(param->key, string);
 414
 415         while ((p = strsep(&string, ":")) != NULL) {
 416                 if (!*p)
 417                         continue;
 418                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 419                 case Opt_sec_none:
 420                         pseudoflavor = RPC_AUTH_NULL;
 421                         break;
 422                 case Opt_sec_sys:
 423                         pseudoflavor = RPC_AUTH_UNIX;
 424                         break;
 425                 case Opt_sec_krb5:
 426                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 427                         break;
 428                 case Opt_sec_krb5i:
 429                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 430                         break;
 431                 case Opt_sec_krb5p:
 432                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 433                         break;
 434                 case Opt_sec_lkey:
 435                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 436                         break;
 437                 case Opt_sec_lkeyi:
 438                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 439                         break;
 440                 case Opt_sec_lkeyp:
 441                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 442                         break;
 443                 case Opt_sec_spkm:
 444                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 445                         break;
 446                 case Opt_sec_spkmi:
 447                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 448                         break;
 449                 case Opt_sec_spkmp:
 450                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 451                         break;
 452                 default:
 453                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 454                 }
 455
 456                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 457                 if (ret < 0)
 458                         return ret;
 459         }
 460
 461         return 0;
 462 }
 463
 464 static int nfs_parse_xprtsec_policy(struct fs_context *fc,
 465                                     struct fs_parameter *param)
 466 {
 467         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 468
 469         trace_nfs_mount_assign(param->key, param->string);
 470
 471         switch (lookup_constant(nfs_xprtsec_policies, param->string, -1)) {
 472         case Opt_xprtsec_none:
 473                 ctx->xprtsec.policy = RPC_XPRTSEC_NONE;
 474                 break;
 475         case Opt_xprtsec_tls:
 476                 ctx->xprtsec.policy = RPC_XPRTSEC_TLS_ANON;
 477                 break;
 478         case Opt_xprtsec_mtls:
 479                 ctx->xprtsec.policy = RPC_XPRTSEC_TLS_X509;
 480                 break;
 481         default:
 482                 return nfs_invalf(fc, "NFS: Unrecognized transport security policy");
 483         }
 484         return 0;
 485 }
 486
 487 static int nfs_parse_version_string(struct fs_context *fc,
 488                                     const char *string)
 489 {
 490         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 491
 492         ctx->flags &= ~NFS_MOUNT_VER3;
 493         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 494         case Opt_vers_2:
 495                 ctx->version = 2;
 496                 break;
 497         case Opt_vers_3:
 498                 ctx->flags |= NFS_MOUNT_VER3;
 499                 ctx->version = 3;
 500                 break;
 501         case Opt_vers_4:
 502                 /* Backward compatibility option. In future,
 503                  * the mount program should always supply
 504                  * a NFSv4 minor version number.
 505                  */
 506                 ctx->version = 4;
 507                 break;
 508         case Opt_vers_4_0:
 509                 ctx->version = 4;
 510                 ctx->minorversion = 0;
 511                 break;
 512         case Opt_vers_4_1:
 513                 ctx->version = 4;
 514                 ctx->minorversion = 1;
 515                 break;
 516         case Opt_vers_4_2:
 517                 ctx->version = 4;
 518                 ctx->minorversion = 2;
 519                 break;
 520         default:
 521                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 522         }
 523         return 0;
 524 }
 525
 526 /*
 527  * Parse a single mount parameter.
 528  */
 529 static int nfs_fs_context_parse_param(struct fs_context *fc,
 530                                       struct fs_parameter *param)
 531 {
 532         struct fs_parse_result result;
 533         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 534         unsigned short protofamily, mountfamily;
 535         unsigned int len;
 536         int ret, opt;
 537
 538         trace_nfs_mount_option(param);
 539
 540         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 541         if (opt < 0)
 542                 return (opt == -ENOPARAM && ctx->sloppy) ? 1 : opt;
 543
 544         if (fc->security)
 545                 ctx->has_sec_mnt_opts = 1;
 546
 547         switch (opt) {
 548         case Opt_source:
 549                 if (fc->source)
 550                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 551                 fc->source = param->string;
 552                 param->string = NULL;
 553                 break;
 554
 555                 /*
 556                  * boolean options:  foo/nofoo
 557                  */
 558         case Opt_soft:
 559                 ctx->flags |= NFS_MOUNT_SOFT;
 560                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 561                 break;
 562         case Opt_softerr:
 563                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 564                 ctx->flags &= ~NFS_MOUNT_SOFT;
 565                 break;
 566         case Opt_hard:
 567                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 568                                 NFS_MOUNT_SOFTERR |
 569                                 NFS_MOUNT_SOFTREVAL);
 570                 break;
 571         case Opt_softreval:
 572                 if (result.negated)
 573                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 574                 else
 575                         ctx->flags |= NFS_MOUNT_SOFTREVAL;
 576                 break;
 577         case Opt_posix:
 578                 if (result.negated)
 579                         ctx->flags &= ~NFS_MOUNT_POSIX;
 580                 else
 581                         ctx->flags |= NFS_MOUNT_POSIX;
 582                 break;
 583         case Opt_cto:
 584                 if (result.negated)
 585                         ctx->flags |= NFS_MOUNT_NOCTO;
 586                 else
 587                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 588                 break;
 589         case Opt_trunkdiscovery:
 590                 if (result.negated)
 591                         ctx->flags &= ~NFS_MOUNT_TRUNK_DISCOVERY;
 592                 else
 593                         ctx->flags |= NFS_MOUNT_TRUNK_DISCOVERY;
 594                 break;
 595         case Opt_ac:
 596                 if (result.negated)
 597                         ctx->flags |= NFS_MOUNT_NOAC;
 598                 else
 599                         ctx->flags &= ~NFS_MOUNT_NOAC;
 600                 break;
 601         case Opt_lock:
 602                 if (result.negated) {
 603                         ctx->lock_status = NFS_LOCK_NOLOCK;
 604                         ctx->flags |= NFS_MOUNT_NONLM;
 605                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 606                 } else {
 607                         ctx->lock_status = NFS_LOCK_LOCK;
 608                         ctx->flags &= ~NFS_MOUNT_NONLM;
 609                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 610                 }
 611                 break;
 612         case Opt_udp:
 613                 ctx->flags &= ~NFS_MOUNT_TCP;
 614                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 615                 break;
 616         case Opt_tcp:
 617         case Opt_rdma:
 618                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 619                 ret = xprt_find_transport_ident(param->key);
 620                 if (ret < 0)
 621                         goto out_bad_transport;
 622                 ctx->nfs_server.protocol = ret;
 623                 break;
 624         case Opt_acl:
 625                 if (result.negated)
 626                         ctx->flags |= NFS_MOUNT_NOACL;
 627                 else
 628                         ctx->flags &= ~NFS_MOUNT_NOACL;
 629                 break;
 630         case Opt_rdirplus:
 631                 if (result.negated)
 632                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 633                 else
 634                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 635                 break;
 636         case Opt_sharecache:
 637                 if (result.negated)
 638                         ctx->flags |= NFS_MOUNT_UNSHARED;
 639                 else
 640                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 641                 break;
 642         case Opt_resvport:
 643                 if (result.negated)
 644                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 645                 else
 646                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 647                 break;
 648         case Opt_fscache_flag:
 649                 if (result.negated)
 650                         ctx->options &= ~NFS_OPTION_FSCACHE;
 651                 else
 652                         ctx->options |= NFS_OPTION_FSCACHE;
 653                 kfree(ctx->fscache_uniq);
 654                 ctx->fscache_uniq = NULL;
 655                 break;
 656         case Opt_fscache:
 657                 trace_nfs_mount_assign(param->key, param->string);
 658                 ctx->options |= NFS_OPTION_FSCACHE;
 659                 kfree(ctx->fscache_uniq);
 660                 ctx->fscache_uniq = param->string;
 661                 param->string = NULL;
 662                 break;
 663         case Opt_migration:
 664                 if (result.negated)
 665                         ctx->options &= ~NFS_OPTION_MIGRATION;
 666                 else
 667                         ctx->options |= NFS_OPTION_MIGRATION;
 668                 break;
 669
 670                 /*
 671                  * options that take numeric values
 672                  */
 673         case Opt_port:
 674                 if (result.uint_32 > USHRT_MAX)
 675                         goto out_of_bounds;
 676                 ctx->nfs_server.port = result.uint_32;
 677                 break;
 678         case Opt_rsize:
 679                 ctx->rsize = result.uint_32;
 680                 break;
 681         case Opt_wsize:
 682                 ctx->wsize = result.uint_32;
 683                 break;
 684         case Opt_bsize:
 685                 ctx->bsize = result.uint_32;
 686                 break;
 687         case Opt_timeo:
 688                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 689                         goto out_of_bounds;
 690                 ctx->timeo = result.uint_32;
 691                 break;
 692         case Opt_retrans:
 693                 if (result.uint_32 > INT_MAX)
 694                         goto out_of_bounds;
 695                 ctx->retrans = result.uint_32;
 696                 break;
 697         case Opt_acregmin:
 698                 ctx->acregmin = result.uint_32;
 699                 break;
 700         case Opt_acregmax:
 701                 ctx->acregmax = result.uint_32;
 702                 break;
 703         case Opt_acdirmin:
 704                 ctx->acdirmin = result.uint_32;
 705                 break;
 706         case Opt_acdirmax:
 707                 ctx->acdirmax = result.uint_32;
 708                 break;
 709         case Opt_actimeo:
 710                 ctx->acregmin = result.uint_32;
 711                 ctx->acregmax = result.uint_32;
 712                 ctx->acdirmin = result.uint_32;
 713                 ctx->acdirmax = result.uint_32;
 714                 break;
 715         case Opt_namelen:
 716                 ctx->namlen = result.uint_32;
 717                 break;
 718         case Opt_mountport:
 719                 if (result.uint_32 > USHRT_MAX)
 720                         goto out_of_bounds;
 721                 ctx->mount_server.port = result.uint_32;
 722                 break;
 723         case Opt_mountvers:
 724                 if (result.uint_32 < NFS_MNT_VERSION ||
 725                     result.uint_32 > NFS_MNT3_VERSION)
 726                         goto out_of_bounds;
 727                 ctx->mount_server.version = result.uint_32;
 728                 break;
 729         case Opt_minorversion:
 730                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 731                         goto out_of_bounds;
 732                 ctx->minorversion = result.uint_32;
 733                 break;
 734
 735                 /*
 736                  * options that take text values
 737                  */
 738         case Opt_v:
 739                 ret = nfs_parse_version_string(fc, param->key + 1);
 740                 if (ret < 0)
 741                         return ret;
 742                 break;
 743         case Opt_vers:
 744                 if (!param->string)
 745                         goto out_invalid_value;
 746                 trace_nfs_mount_assign(param->key, param->string);
 747                 ret = nfs_parse_version_string(fc, param->string);
 748                 if (ret < 0)
 749                         return ret;
 750                 break;
 751         case Opt_sec:
 752                 ret = nfs_parse_security_flavors(fc, param);
 753                 if (ret < 0)
 754                         return ret;
 755                 break;
 756         case Opt_xprtsec:
 757                 ret = nfs_parse_xprtsec_policy(fc, param);
 758                 if (ret < 0)
 759                         return ret;
 760                 break;
 761
 762         case Opt_proto:
 763                 if (!param->string)
 764                         goto out_invalid_value;
 765                 trace_nfs_mount_assign(param->key, param->string);
 766                 protofamily = AF_INET;
 767                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 768                 case Opt_xprt_udp6:
 769                         protofamily = AF_INET6;
 770                         fallthrough;
 771                 case Opt_xprt_udp:
 772                         ctx->flags &= ~NFS_MOUNT_TCP;
 773                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 774                         break;
 775                 case Opt_xprt_tcp6:
 776                         protofamily = AF_INET6;
 777                         fallthrough;
 778                 case Opt_xprt_tcp:
 779                         ctx->flags |= NFS_MOUNT_TCP;
 780                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 781                         break;
 782                 case Opt_xprt_rdma6:
 783                         protofamily = AF_INET6;
 784                         fallthrough;
 785                 case Opt_xprt_rdma:
 786                         /* vector side protocols to TCP */
 787                         ctx->flags |= NFS_MOUNT_TCP;
 788                         ret = xprt_find_transport_ident(param->string);
 789                         if (ret < 0)
 790                                 goto out_bad_transport;
 791                         ctx->nfs_server.protocol = ret;
 792                         break;
 793                 default:
 794                         goto out_bad_transport;
 795                 }
 796
 797                 ctx->protofamily = protofamily;
 798                 break;
 799
 800         case Opt_mountproto:
 801                 if (!param->string)
 802                         goto out_invalid_value;
 803                 trace_nfs_mount_assign(param->key, param->string);
 804                 mountfamily = AF_INET;
 805                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 806                 case Opt_xprt_udp6:
 807                         mountfamily = AF_INET6;
 808                         fallthrough;
 809                 case Opt_xprt_udp:
 810                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 811                         break;
 812                 case Opt_xprt_tcp6:
 813                         mountfamily = AF_INET6;
 814                         fallthrough;
 815                 case Opt_xprt_tcp:
 816                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 817                         break;
 818                 case Opt_xprt_rdma: /* not used for side protocols */
 819                 default:
 820                         goto out_bad_transport;
 821                 }
 822                 ctx->mountfamily = mountfamily;
 823                 break;
 824
 825         case Opt_addr:
 826                 trace_nfs_mount_assign(param->key, param->string);
 827                 len = rpc_pton(fc->net_ns, param->string, param->size,
 828                                &ctx->nfs_server.address,
 829                                sizeof(ctx->nfs_server._address));
 830                 if (len == 0)
 831                         goto out_invalid_address;
 832                 ctx->nfs_server.addrlen = len;
 833                 break;
 834         case Opt_clientaddr:
 835                 trace_nfs_mount_assign(param->key, param->string);
 836                 kfree(ctx->client_address);
 837                 ctx->client_address = param->string;
 838                 param->string = NULL;
 839                 break;
 840         case Opt_mounthost:
 841                 trace_nfs_mount_assign(param->key, param->string);
 842                 kfree(ctx->mount_server.hostname);
 843                 ctx->mount_server.hostname = param->string;
 844                 param->string = NULL;
 845                 break;
 846         case Opt_mountaddr:
 847                 trace_nfs_mount_assign(param->key, param->string);
 848                 len = rpc_pton(fc->net_ns, param->string, param->size,
 849                                &ctx->mount_server.address,
 850                                sizeof(ctx->mount_server._address));
 851                 if (len == 0)
 852                         goto out_invalid_address;
 853                 ctx->mount_server.addrlen = len;
 854                 break;
 855         case Opt_nconnect:
 856                 trace_nfs_mount_assign(param->key, param->string);
 857                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 858                         goto out_of_bounds;
 859                 ctx->nfs_server.nconnect = result.uint_32;
 860                 break;
 861         case Opt_max_connect:
 862                 trace_nfs_mount_assign(param->key, param->string);
 863                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
 864                         goto out_of_bounds;
 865                 ctx->nfs_server.max_connect = result.uint_32;
 866                 break;
 867         case Opt_lookupcache:
 868                 trace_nfs_mount_assign(param->key, param->string);
 869                 switch (result.uint_32) {
 870                 case Opt_lookupcache_all:
 871                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 872                         break;
 873                 case Opt_lookupcache_positive:
 874                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 875                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 876                         break;
 877                 case Opt_lookupcache_none:
 878                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 879                         break;
 880                 default:
 881                         goto out_invalid_value;
 882                 }
 883                 break;
 884         case Opt_local_lock:
 885                 trace_nfs_mount_assign(param->key, param->string);
 886                 switch (result.uint_32) {
 887                 case Opt_local_lock_all:
 888                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 889                                        NFS_MOUNT_LOCAL_FCNTL);
 890                         break;
 891                 case Opt_local_lock_flock:
 892                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 893                         break;
 894                 case Opt_local_lock_posix:
 895                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 896                         break;
 897                 case Opt_local_lock_none:
 898                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 899                                         NFS_MOUNT_LOCAL_FCNTL);
 900                         break;
 901                 default:
 902                         goto out_invalid_value;
 903                 }
 904                 break;
 905         case Opt_write:
 906                 trace_nfs_mount_assign(param->key, param->string);
 907                 switch (result.uint_32) {
 908                 case Opt_write_lazy:
 909                         ctx->flags &=
 910                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 911                         break;
 912                 case Opt_write_eager:
 913                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 914                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 915                         break;
 916                 case Opt_write_wait:
 917                         ctx->flags |=
 918                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 919                         break;
 920                 default:
 921                         goto out_invalid_value;
 922                 }
 923                 break;
 924
 925                 /*
 926                  * Special options
 927                  */
 928         case Opt_sloppy:
 929                 ctx->sloppy = true;
 930                 break;
 931         }
 932
 933         return 0;
 934
 935 out_invalid_value:
 936         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 937 out_invalid_address:
 938         return nfs_invalf(fc, "NFS: Bad IP address specified");
 939 out_of_bounds:
 940         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 941 out_bad_transport:
 942         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 943 }
 944
 945 /*
 946  * Split fc->source into "hostname:export_path".
 947  *
 948  * The leftmost colon demarks the split between the server's hostname
 949  * and the export path.  If the hostname starts with a left square
 950  * bracket, then it may contain colons.
 951  *
 952  * Note: caller frees hostname and export path, even on error.
 953  */
 954 static int nfs_parse_source(struct fs_context *fc,
 955                             size_t maxnamlen, size_t maxpathlen)
 956 {
 957         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 958         const char *dev_name = fc->source;
 959         size_t len;
 960         const char *end;
 961
 962         if (unlikely(!dev_name || !*dev_name))
 963                 return -EINVAL;
 964
 965         /* Is the host name protected with square brakcets? */
 966         if (*dev_name == '[') {
 967                 end = strchr(++dev_name, ']');
 968                 if (end == NULL || end[1] != ':')
 969                         goto out_bad_devname;
 970
 971                 len = end - dev_name;
 972                 end++;
 973         } else {
 974                 const char *comma;
 975
 976                 end = strchr(dev_name, ':');
 977                 if (end == NULL)
 978                         goto out_bad_devname;
 979                 len = end - dev_name;
 980
 981                 /* kill possible hostname list: not supported */
 982                 comma = memchr(dev_name, ',', len);
 983                 if (comma)
 984                         len = comma - dev_name;
 985         }
 986
 987         if (len > maxnamlen)
 988                 goto out_hostname;
 989
 990         kfree(ctx->nfs_server.hostname);
 991
 992         /* N.B. caller will free nfs_server.hostname in all cases */
 993         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 994         if (!ctx->nfs_server.hostname)
 995                 goto out_nomem;
 996         len = strlen(++end);
 997         if (len > maxpathlen)
 998                 goto out_path;
 999         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
1000         if (!ctx->nfs_server.export_path)
1001                 goto out_nomem;
1002
1003         trace_nfs_mount_path(ctx->nfs_server.export_path);
1004         return 0;
1005
1006 out_bad_devname:
1007         return nfs_invalf(fc, "NFS: device name not in host:path format");
1008 out_nomem:
1009         nfs_errorf(fc, "NFS: not enough memory to parse device name");
1010         return -ENOMEM;
1011 out_hostname:
1012         nfs_errorf(fc, "NFS: server hostname too long");
1013         return -ENAMETOOLONG;
1014 out_path:
1015         nfs_errorf(fc, "NFS: export pathname too long");
1016         return -ENAMETOOLONG;
1017 }
1018
1019 static inline bool is_remount_fc(struct fs_context *fc)
1020 {
1021         return fc->root != NULL;
1022 }
1023
1024 /*
1025  * Parse monolithic NFS2/NFS3 mount data
1026  * - fills in the mount root filehandle
1027  *
1028  * For option strings, user space handles the following behaviors:
1029  *
1030  * + DNS: mapping server host name to IP address ("addr=" option)
1031  *
1032  * + failure mode: how to behave if a mount request can't be handled
1033  *   immediately ("fg/bg" option)
1034  *
1035  * + retry: how often to retry a mount request ("retry=" option)
1036  *
1037  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1038  *   mountproto=tcp after mountproto=udp, and so on
1039  */
1040 static int nfs23_parse_monolithic(struct fs_context *fc,
1041                                   struct nfs_mount_data *data)
1042 {
1043         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1044         struct nfs_fh *mntfh = ctx->mntfh;
1045         struct sockaddr_storage *sap = &ctx->nfs_server._address;
1046         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1047         int ret;
1048
1049         if (data == NULL)
1050                 goto out_no_data;
1051
1052         ctx->version = NFS_DEFAULT_VERSION;
1053         switch (data->version) {
1054         case 1:
1055                 data->namlen = 0;
1056                 fallthrough;
1057         case 2:
1058                 data->bsize = 0;
1059                 fallthrough;
1060         case 3:
1061                 if (data->flags & NFS_MOUNT_VER3)
1062                         goto out_no_v3;
1063                 data->root.size = NFS2_FHSIZE;
1064                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1065                 /* Turn off security negotiation */
1066                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1067                 fallthrough;
1068         case 4:
1069                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1070                         goto out_no_sec;
1071                 fallthrough;
1072         case 5:
1073                 memset(data->context, 0, sizeof(data->context));
1074                 fallthrough;
1075         case 6:
1076                 if (data->flags & NFS_MOUNT_VER3) {
1077                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1078                                 goto out_invalid_fh;
1079                         mntfh->size = data->root.size;
1080                         ctx->version = 3;
1081                 } else {
1082                         mntfh->size = NFS2_FHSIZE;
1083                         ctx->version = 2;
1084                 }
1085
1086
1087                 memcpy(mntfh->data, data->root.data, mntfh->size);
1088                 if (mntfh->size < sizeof(mntfh->data))
1089                         memset(mntfh->data + mntfh->size, 0,
1090                                sizeof(mntfh->data) - mntfh->size);
1091
1092                 /*
1093                  * for proto == XPRT_TRANSPORT_UDP, which is what uses
1094                  * to_exponential, implying shift: limit the shift value
1095                  * to BITS_PER_LONG (majortimeo is unsigned long)
1096                  */
1097                 if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1098                         if (data->retrans >= 64) /* shift value is too large */
1099                                 goto out_invalid_data;
1100
1101                 /*
1102                  * Translate to nfs_fs_context, which nfs_fill_super
1103                  * can deal with.
1104                  */
1105                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
1106                 ctx->flags      |= extra_flags;
1107                 ctx->rsize      = data->rsize;
1108                 ctx->wsize      = data->wsize;
1109                 ctx->timeo      = data->timeo;
1110                 ctx->retrans    = data->retrans;
1111                 ctx->acregmin   = data->acregmin;
1112                 ctx->acregmax   = data->acregmax;
1113                 ctx->acdirmin   = data->acdirmin;
1114                 ctx->acdirmax   = data->acdirmax;
1115                 ctx->need_mount = false;
1116
1117                 if (!is_remount_fc(fc)) {
1118                         memcpy(sap, &data->addr, sizeof(data->addr));
1119                         ctx->nfs_server.addrlen = sizeof(data->addr);
1120                         ctx->nfs_server.port = ntohs(data->addr.sin_port);
1121                 }
1122
1123                 if (sap->ss_family != AF_INET ||
1124                     !nfs_verify_server_address(sap))
1125                         goto out_no_address;
1126
1127                 if (!(data->flags & NFS_MOUNT_TCP))
1128                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1129                 /* N.B. caller will free nfs_server.hostname in all cases */
1130                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1131                 if (!ctx->nfs_server.hostname)
1132                         goto out_nomem;
1133
1134                 ctx->namlen             = data->namlen;
1135                 ctx->bsize              = data->bsize;
1136
1137                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1138                         ctx->selected_flavor = data->pseudoflavor;
1139                 else
1140                         ctx->selected_flavor = RPC_AUTH_UNIX;
1141
1142                 if (!(data->flags & NFS_MOUNT_NONLM))
1143                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1144                                          NFS_MOUNT_LOCAL_FCNTL);
1145                 else
1146                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1147                                         NFS_MOUNT_LOCAL_FCNTL);
1148
1149                 /*
1150                  * The legacy version 6 binary mount data from userspace has a
1151                  * field used only to transport selinux information into the
1152                  * kernel.  To continue to support that functionality we
1153                  * have a touch of selinux knowledge here in the NFS code. The
1154                  * userspace code converted context=blah to just blah so we are
1155                  * converting back to the full string selinux understands.
1156                  */
1157                 if (data->context[0]){
1158 #ifdef CONFIG_SECURITY_SELINUX
1159                         int ret;
1160
1161                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1162                         ret = vfs_parse_fs_string(fc, "context",
1163                                                   data->context, strlen(data->context));
1164                         if (ret < 0)
1165                                 return ret;
1166 #else
1167                         return -EINVAL;
1168 #endif
1169                 }
1170
1171                 break;
1172         default:
1173                 goto generic;
1174         }
1175
1176         ret = nfs_validate_transport_protocol(fc, ctx);
1177         if (ret)
1178                 return ret;
1179
1180         ctx->skip_reconfig_option_check = true;
1181         return 0;
1182
1183 generic:
1184         return generic_parse_monolithic(fc, data);
1185
1186 out_no_data:
1187         if (is_remount_fc(fc)) {
1188                 ctx->skip_reconfig_option_check = true;
1189                 return 0;
1190         }
1191         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1192
1193 out_no_v3:
1194         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1195
1196 out_no_sec:
1197         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1198
1199 out_nomem:
1200         return -ENOMEM;
1201
1202 out_no_address:
1203         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1204
1205 out_invalid_fh:
1206         return nfs_invalf(fc, "NFS: invalid root filehandle");
1207
1208 out_invalid_data:
1209         return nfs_invalf(fc, "NFS: invalid binary mount data");
1210 }
1211
1212 #if IS_ENABLED(CONFIG_NFS_V4)
1213 struct compat_nfs_string {
1214         compat_uint_t len;
1215         compat_uptr_t data;
1216 };
1217
1218 static inline void compat_nfs_string(struct nfs_string *dst,
1219                                      struct compat_nfs_string *src)
1220 {
1221         dst->data = compat_ptr(src->data);
1222         dst->len = src->len;
1223 }
1224
1225 struct compat_nfs4_mount_data_v1 {
1226         compat_int_t version;
1227         compat_int_t flags;
1228         compat_int_t rsize;
1229         compat_int_t wsize;
1230         compat_int_t timeo;
1231         compat_int_t retrans;
1232         compat_int_t acregmin;
1233         compat_int_t acregmax;
1234         compat_int_t acdirmin;
1235         compat_int_t acdirmax;
1236         struct compat_nfs_string client_addr;
1237         struct compat_nfs_string mnt_path;
1238         struct compat_nfs_string hostname;
1239         compat_uint_t host_addrlen;
1240         compat_uptr_t host_addr;
1241         compat_int_t proto;
1242         compat_int_t auth_flavourlen;
1243         compat_uptr_t auth_flavours;
1244 };
1245
1246 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1247 {
1248         struct compat_nfs4_mount_data_v1 *compat =
1249                         (struct compat_nfs4_mount_data_v1 *)data;
1250
1251         /* copy the fields backwards */
1252         data->auth_flavours = compat_ptr(compat->auth_flavours);
1253         data->auth_flavourlen = compat->auth_flavourlen;
1254         data->proto = compat->proto;
1255         data->host_addr = compat_ptr(compat->host_addr);
1256         data->host_addrlen = compat->host_addrlen;
1257         compat_nfs_string(&data->hostname, &compat->hostname);
1258         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1259         compat_nfs_string(&data->client_addr, &compat->client_addr);
1260         data->acdirmax = compat->acdirmax;
1261         data->acdirmin = compat->acdirmin;
1262         data->acregmax = compat->acregmax;
1263         data->acregmin = compat->acregmin;
1264         data->retrans = compat->retrans;
1265         data->timeo = compat->timeo;
1266         data->wsize = compat->wsize;
1267         data->rsize = compat->rsize;
1268         data->flags = compat->flags;
1269         data->version = compat->version;
1270 }
1271
1272 /*
1273  * Validate NFSv4 mount options
1274  */
1275 static int nfs4_parse_monolithic(struct fs_context *fc,
1276                                  struct nfs4_mount_data *data)
1277 {
1278         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1279         struct sockaddr_storage *sap = &ctx->nfs_server._address;
1280         int ret;
1281         char *c;
1282
1283         if (!data) {
1284                 if (is_remount_fc(fc))
1285                         goto done;
1286                 return nfs_invalf(fc,
1287                         "NFS4: mount program didn't pass any mount data");
1288         }
1289
1290         ctx->version = 4;
1291
1292         if (data->version != 1)
1293                 return generic_parse_monolithic(fc, data);
1294
1295         if (in_compat_syscall())
1296                 nfs4_compat_mount_data_conv(data);
1297
1298         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1299                 goto out_no_address;
1300         if (data->host_addrlen == 0)
1301                 goto out_no_address;
1302         ctx->nfs_server.addrlen = data->host_addrlen;
1303         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1304                 return -EFAULT;
1305         if (!nfs_verify_server_address(sap))
1306                 goto out_no_address;
1307         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1308
1309         if (data->auth_flavourlen) {
1310                 rpc_authflavor_t pseudoflavor;
1311
1312                 if (data->auth_flavourlen > 1)
1313                         goto out_inval_auth;
1314                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1315                                    sizeof(pseudoflavor)))
1316                         return -EFAULT;
1317                 ctx->selected_flavor = pseudoflavor;
1318         } else {
1319                 ctx->selected_flavor = RPC_AUTH_UNIX;
1320         }
1321
1322         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1323         if (IS_ERR(c))
1324                 return PTR_ERR(c);
1325         ctx->nfs_server.hostname = c;
1326
1327         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1328         if (IS_ERR(c))
1329                 return PTR_ERR(c);
1330         ctx->nfs_server.export_path = c;
1331         trace_nfs_mount_path(c);
1332
1333         c = strndup_user(data->client_addr.data, 16);
1334         if (IS_ERR(c))
1335                 return PTR_ERR(c);
1336         ctx->client_address = c;
1337
1338         /*
1339          * Translate to nfs_fs_context, which nfs_fill_super
1340          * can deal with.
1341          */
1342
1343         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1344         ctx->rsize      = data->rsize;
1345         ctx->wsize      = data->wsize;
1346         ctx->timeo      = data->timeo;
1347         ctx->retrans    = data->retrans;
1348         ctx->acregmin   = data->acregmin;
1349         ctx->acregmax   = data->acregmax;
1350         ctx->acdirmin   = data->acdirmin;
1351         ctx->acdirmax   = data->acdirmax;
1352         ctx->nfs_server.protocol = data->proto;
1353         ret = nfs_validate_transport_protocol(fc, ctx);
1354         if (ret)
1355                 return ret;
1356 done:
1357         ctx->skip_reconfig_option_check = true;
1358         return 0;
1359
1360 out_inval_auth:
1361         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1362                       data->auth_flavourlen);
1363
1364 out_no_address:
1365         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1366 }
1367 #endif
1368
1369 /*
1370  * Parse a monolithic block of data from sys_mount().
1371  */
1372 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1373                                            void *data)
1374 {
1375         if (fc->fs_type == &nfs_fs_type)
1376                 return nfs23_parse_monolithic(fc, data);
1377
1378 #if IS_ENABLED(CONFIG_NFS_V4)
1379         if (fc->fs_type == &nfs4_fs_type)
1380                 return nfs4_parse_monolithic(fc, data);
1381 #endif
1382
1383         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1384 }
1385
1386 /*
1387  * Validate the preparsed information in the config.
1388  */
1389 static int nfs_fs_context_validate(struct fs_context *fc)
1390 {
1391         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1392         struct nfs_subversion *nfs_mod;
1393         struct sockaddr_storage *sap = &ctx->nfs_server._address;
1394         int max_namelen = PAGE_SIZE;
1395         int max_pathlen = NFS_MAXPATHLEN;
1396         int port = 0;
1397         int ret;
1398
1399         if (!fc->source)
1400                 goto out_no_device_name;
1401
1402         /* Check for sanity first. */
1403         if (ctx->minorversion && ctx->version != 4)
1404                 goto out_minorversion_mismatch;
1405
1406         if (ctx->options & NFS_OPTION_MIGRATION &&
1407             (ctx->version != 4 || ctx->minorversion != 0))
1408                 goto out_migration_misuse;
1409
1410         /* Verify that any proto=/mountproto= options match the address
1411          * families in the addr=/mountaddr= options.
1412          */
1413         if (ctx->protofamily != AF_UNSPEC &&
1414             ctx->protofamily != ctx->nfs_server.address.sa_family)
1415                 goto out_proto_mismatch;
1416
1417         if (ctx->mountfamily != AF_UNSPEC) {
1418                 if (ctx->mount_server.addrlen) {
1419                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1420                                 goto out_mountproto_mismatch;
1421                 } else {
1422                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1423                                 goto out_mountproto_mismatch;
1424                 }
1425         }
1426
1427         if (!nfs_verify_server_address(sap))
1428                 goto out_no_address;
1429
1430         ret = nfs_validate_transport_protocol(fc, ctx);
1431         if (ret)
1432                 return ret;
1433
1434         if (ctx->version == 4) {
1435                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1436                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1437                                 port = NFS_RDMA_PORT;
1438                         else
1439                                 port = NFS_PORT;
1440                         max_namelen = NFS4_MAXNAMLEN;
1441                         max_pathlen = NFS4_MAXPATHLEN;
1442                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1443                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1444                                         NFS_MOUNT_LOCAL_FCNTL);
1445                 } else {
1446                         goto out_v4_not_compiled;
1447                 }
1448         } else {
1449                 nfs_set_mount_transport_protocol(ctx);
1450                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1451                         port = NFS_RDMA_PORT;
1452         }
1453
1454         nfs_set_port(sap, &ctx->nfs_server.port, port);
1455
1456         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1457         if (ret < 0)
1458                 return ret;
1459
1460         /* Load the NFS protocol module if we haven't done so yet */
1461         if (!ctx->nfs_mod) {
1462                 nfs_mod = get_nfs_version(ctx->version);
1463                 if (IS_ERR(nfs_mod)) {
1464                         ret = PTR_ERR(nfs_mod);
1465                         goto out_version_unavailable;
1466                 }
1467                 ctx->nfs_mod = nfs_mod;
1468         }
1469
1470         /* Ensure the filesystem context has the correct fs_type */
1471         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1472                 module_put(fc->fs_type->owner);
1473                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1474                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1475         }
1476         return 0;
1477
1478 out_no_device_name:
1479         return nfs_invalf(fc, "NFS: Device name not specified");
1480 out_v4_not_compiled:
1481         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1482         return -EPROTONOSUPPORT;
1483 out_no_address:
1484         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1485 out_mountproto_mismatch:
1486         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1487 out_proto_mismatch:
1488         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1489 out_minorversion_mismatch:
1490         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1491                           ctx->version, ctx->minorversion);
1492 out_migration_misuse:
1493         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1494 out_version_unavailable:
1495         nfs_errorf(fc, "NFS: Version unavailable");
1496         return ret;
1497 }
1498
1499 /*
1500  * Create an NFS superblock by the appropriate method.
1501  */
1502 static int nfs_get_tree(struct fs_context *fc)
1503 {
1504         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1505         int err = nfs_fs_context_validate(fc);
1506
1507         if (err)
1508                 return err;
1509         if (!ctx->internal)
1510                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1511         else
1512                 return nfs_get_tree_common(fc);
1513 }
1514
1515 /*
1516  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1517  * it can't deal with resource pointers in the filesystem context, so we have
1518  * to do that.  We need to clear pointers, copy data or get extra refs as
1519  * appropriate.
1520  */
1521 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1522 {
1523         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1524
1525         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1526         if (!ctx)
1527                 return -ENOMEM;
1528
1529         ctx->mntfh = nfs_alloc_fhandle();
1530         if (!ctx->mntfh) {
1531                 kfree(ctx);
1532                 return -ENOMEM;
1533         }
1534         nfs_copy_fh(ctx->mntfh, src->mntfh);
1535
1536         __module_get(ctx->nfs_mod->owner);
1537         ctx->client_address             = NULL;
1538         ctx->mount_server.hostname      = NULL;
1539         ctx->nfs_server.export_path     = NULL;
1540         ctx->nfs_server.hostname        = NULL;
1541         ctx->fscache_uniq               = NULL;
1542         ctx->clone_data.fattr           = NULL;
1543         fc->fs_private = ctx;
1544         return 0;
1545 }
1546
1547 static void nfs_fs_context_free(struct fs_context *fc)
1548 {
1549         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1550
1551         if (ctx) {
1552                 if (ctx->server)
1553                         nfs_free_server(ctx->server);
1554                 if (ctx->nfs_mod)
1555                         put_nfs_version(ctx->nfs_mod);
1556                 kfree(ctx->client_address);
1557                 kfree(ctx->mount_server.hostname);
1558                 kfree(ctx->nfs_server.export_path);
1559                 kfree(ctx->nfs_server.hostname);
1560                 kfree(ctx->fscache_uniq);
1561                 nfs_free_fhandle(ctx->mntfh);
1562                 nfs_free_fattr(ctx->clone_data.fattr);
1563                 kfree(ctx);
1564         }
1565 }
1566
1567 static const struct fs_context_operations nfs_fs_context_ops = {
1568         .free                   = nfs_fs_context_free,
1569         .dup                    = nfs_fs_context_dup,
1570         .parse_param            = nfs_fs_context_parse_param,
1571         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1572         .get_tree               = nfs_get_tree,
1573         .reconfigure            = nfs_reconfigure,
1574 };
1575
1576 /*
1577  * Prepare superblock configuration.  We use the namespaces attached to the
1578  * context.  This may be the current process's namespaces, or it may be a
1579  * container's namespaces.
1580  */
1581 static int nfs_init_fs_context(struct fs_context *fc)
1582 {
1583         struct nfs_fs_context *ctx;
1584
1585         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1586         if (unlikely(!ctx))
1587                 return -ENOMEM;
1588
1589         ctx->mntfh = nfs_alloc_fhandle();
1590         if (unlikely(!ctx->mntfh)) {
1591                 kfree(ctx);
1592                 return -ENOMEM;
1593         }
1594
1595         ctx->protofamily        = AF_UNSPEC;
1596         ctx->mountfamily        = AF_UNSPEC;
1597         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1598
1599         if (fc->root) {
1600                 /* reconfigure, start with the current config */
1601                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1602                 struct net *net = nfss->nfs_client->cl_net;
1603
1604                 ctx->flags              = nfss->flags;
1605                 ctx->rsize              = nfss->rsize;
1606                 ctx->wsize              = nfss->wsize;
1607                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1608                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1609                 ctx->acregmin           = nfss->acregmin / HZ;
1610                 ctx->acregmax           = nfss->acregmax / HZ;
1611                 ctx->acdirmin           = nfss->acdirmin / HZ;
1612                 ctx->acdirmax           = nfss->acdirmax / HZ;
1613                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1614                 ctx->nfs_server.port    = nfss->port;
1615                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1616                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1617                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1618
1619                 memcpy(&ctx->nfs_server._address, &nfss->nfs_client->cl_addr,
1620                         ctx->nfs_server.addrlen);
1621
1622                 if (fc->net_ns != net) {
1623                         put_net(fc->net_ns);
1624                         fc->net_ns = get_net(net);
1625                 }
1626
1627                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1628                 __module_get(ctx->nfs_mod->owner);
1629         } else {
1630                 /* defaults */
1631                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1632                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1633                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1634                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1635                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1636                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1637                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1638                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1639                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1640                 ctx->minorversion       = 0;
1641                 ctx->need_mount         = true;
1642                 ctx->xprtsec.policy     = RPC_XPRTSEC_NONE;
1643                 ctx->xprtsec.cert_serial        = TLS_NO_CERT;
1644                 ctx->xprtsec.privkey_serial     = TLS_NO_PRIVKEY;
1645
1646                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1647         }
1648         fc->fs_private = ctx;
1649         fc->ops = &nfs_fs_context_ops;
1650         return 0;
1651 }
1652
1653 struct file_system_type nfs_fs_type = {
1654         .owner                  = THIS_MODULE,
1655         .name                   = "nfs",
1656         .init_fs_context        = nfs_init_fs_context,
1657         .parameters             = nfs_fs_parameters,
1658         .kill_sb                = nfs_kill_super,
1659         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1660 };
1661 MODULE_ALIAS_FS("nfs");
1662 EXPORT_SYMBOL_GPL(nfs_fs_type);
1663
1664 #if IS_ENABLED(CONFIG_NFS_V4)
1665 struct file_system_type nfs4_fs_type = {
1666         .owner                  = THIS_MODULE,
1667         .name                   = "nfs4",
1668         .init_fs_context        = nfs_init_fs_context,
1669         .parameters             = nfs_fs_parameters,
1670         .kill_sb                = nfs_kill_super,
1671         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1672 };
1673 MODULE_ALIAS_FS("nfs4");
1674 MODULE_ALIAS("nfs4");
1675 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1676 #endif /* CONFIG_NFS_V4 */