fs/btrfs/tree-checker.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) Qu Wenruo 2017.  All rights reserved.
   4  */
   5
   6 /*
   7  * The module is used to catch unexpected/corrupted tree block data.
   8  * Such behavior can be caused either by a fuzzed image or bugs.
   9  *
  10  * The objective is to do leaf/node validation checks when tree block is read
  11  * from disk, and check *every* possible member, so other code won't
  12  * need to checking them again.
  13  *
  14  * Due to the potential and unwanted damage, every checker needs to be
  15  * carefully reviewed otherwise so it does not prevent mount of valid images.
  16  */
  17
  18 #include <linux/types.h>
  19 #include <linux/stddef.h>
  20 #include <linux/error-injection.h>
  21 #include "messages.h"
  22 #include "ctree.h"
  23 #include "tree-checker.h"
  24 #include "disk-io.h"
  25 #include "compression.h"
  26 #include "volumes.h"
  27 #include "misc.h"
  28 #include "fs.h"
  29 #include "accessors.h"
  30 #include "file-item.h"
  31 #include "inode-item.h"
  32 #include "dir-item.h"
  33 #include "raid-stripe-tree.h"
  34
  35 /*
  36  * Error message should follow the following format:
  37  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
  38  *
  39  * @type:       leaf or node
  40  * @identifier: the necessary info to locate the leaf/node.
  41  *              It's recommended to decode key.objecitd/offset if it's
  42  *              meaningful.
  43  * @reason:     describe the error
  44  * @bad_value:  optional, it's recommended to output bad value and its
  45  *              expected value (range).
  46  *
  47  * Since comma is used to separate the components, only space is allowed
  48  * inside each component.
  49  */
  50
  51 /*
  52  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
  53  * Allows callers to customize the output.
  54  */
  55 __printf(3, 4)
  56 __cold
  57 static void generic_err(const struct extent_buffer *eb, int slot,
  58                         const char *fmt, ...)
  59 {
  60         const struct btrfs_fs_info *fs_info = eb->fs_info;
  61         struct va_format vaf;
  62         va_list args;
  63
  64         va_start(args, fmt);
  65
  66         vaf.fmt = fmt;
  67         vaf.va = &args;
  68
  69         btrfs_crit(fs_info,
  70                 "corrupt %s: root=%llu block=%llu slot=%d, %pV",
  71                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
  72                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
  73         va_end(args);
  74 }
  75
  76 /*
  77  * Customized reporter for extent data item, since its key objectid and
  78  * offset has its own meaning.
  79  */
  80 __printf(3, 4)
  81 __cold
  82 static void file_extent_err(const struct extent_buffer *eb, int slot,
  83                             const char *fmt, ...)
  84 {
  85         const struct btrfs_fs_info *fs_info = eb->fs_info;
  86         struct btrfs_key key;
  87         struct va_format vaf;
  88         va_list args;
  89
  90         btrfs_item_key_to_cpu(eb, &key, slot);
  91         va_start(args, fmt);
  92
  93         vaf.fmt = fmt;
  94         vaf.va = &args;
  95
  96         btrfs_crit(fs_info,
  97         "corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
  98                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
  99                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 100                 key.objectid, key.offset, &vaf);
 101         va_end(args);
 102 }
 103
 104 /*
 105  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
 106  * Else return 1
 107  */
 108 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)                     \
 109 ({                                                                            \
 110         if (unlikely(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)),      \
 111                                  (alignment))))                               \
 112                 file_extent_err((leaf), (slot),                               \
 113         "invalid %s for file extent, have %llu, should be aligned to %u",     \
 114                         (#name), btrfs_file_extent_##name((leaf), (fi)),      \
 115                         (alignment));                                         \
 116         (!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
 117 })
 118
 119 static u64 file_extent_end(struct extent_buffer *leaf,
 120                            struct btrfs_key *key,
 121                            struct btrfs_file_extent_item *extent)
 122 {
 123         u64 end;
 124         u64 len;
 125
 126         if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
 127                 len = btrfs_file_extent_ram_bytes(leaf, extent);
 128                 end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
 129         } else {
 130                 len = btrfs_file_extent_num_bytes(leaf, extent);
 131                 end = key->offset + len;
 132         }
 133         return end;
 134 }
 135
 136 /*
 137  * Customized report for dir_item, the only new important information is
 138  * key->objectid, which represents inode number
 139  */
 140 __printf(3, 4)
 141 __cold
 142 static void dir_item_err(const struct extent_buffer *eb, int slot,
 143                          const char *fmt, ...)
 144 {
 145         const struct btrfs_fs_info *fs_info = eb->fs_info;
 146         struct btrfs_key key;
 147         struct va_format vaf;
 148         va_list args;
 149
 150         btrfs_item_key_to_cpu(eb, &key, slot);
 151         va_start(args, fmt);
 152
 153         vaf.fmt = fmt;
 154         vaf.va = &args;
 155
 156         btrfs_crit(fs_info,
 157                 "corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
 158                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
 159                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 160                 key.objectid, &vaf);
 161         va_end(args);
 162 }
 163
 164 /*
 165  * This functions checks prev_key->objectid, to ensure current key and prev_key
 166  * share the same objectid as inode number.
 167  *
 168  * This is to detect missing INODE_ITEM in subvolume trees.
 169  *
 170  * Return true if everything is OK or we don't need to check.
 171  * Return false if anything is wrong.
 172  */
 173 static bool check_prev_ino(struct extent_buffer *leaf,
 174                            struct btrfs_key *key, int slot,
 175                            struct btrfs_key *prev_key)
 176 {
 177         /* No prev key, skip check */
 178         if (slot == 0)
 179                 return true;
 180
 181         /* Only these key->types needs to be checked */
 182         ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
 183                key->type == BTRFS_INODE_REF_KEY ||
 184                key->type == BTRFS_DIR_INDEX_KEY ||
 185                key->type == BTRFS_DIR_ITEM_KEY ||
 186                key->type == BTRFS_EXTENT_DATA_KEY);
 187
 188         /*
 189          * Only subvolume trees along with their reloc trees need this check.
 190          * Things like log tree doesn't follow this ino requirement.
 191          */
 192         if (!is_fstree(btrfs_header_owner(leaf)))
 193                 return true;
 194
 195         if (key->objectid == prev_key->objectid)
 196                 return true;
 197
 198         /* Error found */
 199         dir_item_err(leaf, slot,
 200                 "invalid previous key objectid, have %llu expect %llu",
 201                 prev_key->objectid, key->objectid);
 202         return false;
 203 }
 204 static int check_extent_data_item(struct extent_buffer *leaf,
 205                                   struct btrfs_key *key, int slot,
 206                                   struct btrfs_key *prev_key)
 207 {
 208         struct btrfs_fs_info *fs_info = leaf->fs_info;
 209         struct btrfs_file_extent_item *fi;
 210         u32 sectorsize = fs_info->sectorsize;
 211         u32 item_size = btrfs_item_size(leaf, slot);
 212         u64 extent_end;
 213
 214         if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 215                 file_extent_err(leaf, slot,
 216 "unaligned file_offset for file extent, have %llu should be aligned to %u",
 217                         key->offset, sectorsize);
 218                 return -EUCLEAN;
 219         }
 220
 221         /*
 222          * Previous key must have the same key->objectid (ino).
 223          * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
 224          * But if objectids mismatch, it means we have a missing
 225          * INODE_ITEM.
 226          */
 227         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
 228                 return -EUCLEAN;
 229
 230         fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
 231
 232         /*
 233          * Make sure the item contains at least inline header, so the file
 234          * extent type is not some garbage.
 235          */
 236         if (unlikely(item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START)) {
 237                 file_extent_err(leaf, slot,
 238                                 "invalid item size, have %u expect [%zu, %u)",
 239                                 item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
 240                                 SZ_4K);
 241                 return -EUCLEAN;
 242         }
 243         if (unlikely(btrfs_file_extent_type(leaf, fi) >=
 244                      BTRFS_NR_FILE_EXTENT_TYPES)) {
 245                 file_extent_err(leaf, slot,
 246                 "invalid type for file extent, have %u expect range [0, %u]",
 247                         btrfs_file_extent_type(leaf, fi),
 248                         BTRFS_NR_FILE_EXTENT_TYPES - 1);
 249                 return -EUCLEAN;
 250         }
 251
 252         /*
 253          * Support for new compression/encryption must introduce incompat flag,
 254          * and must be caught in open_ctree().
 255          */
 256         if (unlikely(btrfs_file_extent_compression(leaf, fi) >=
 257                      BTRFS_NR_COMPRESS_TYPES)) {
 258                 file_extent_err(leaf, slot,
 259         "invalid compression for file extent, have %u expect range [0, %u]",
 260                         btrfs_file_extent_compression(leaf, fi),
 261                         BTRFS_NR_COMPRESS_TYPES - 1);
 262                 return -EUCLEAN;
 263         }
 264         if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
 265                 file_extent_err(leaf, slot,
 266                         "invalid encryption for file extent, have %u expect 0",
 267                         btrfs_file_extent_encryption(leaf, fi));
 268                 return -EUCLEAN;
 269         }
 270         if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
 271                 /* Inline extent must have 0 as key offset */
 272                 if (unlikely(key->offset)) {
 273                         file_extent_err(leaf, slot,
 274                 "invalid file_offset for inline file extent, have %llu expect 0",
 275                                 key->offset);
 276                         return -EUCLEAN;
 277                 }
 278
 279                 /* Compressed inline extent has no on-disk size, skip it */
 280                 if (btrfs_file_extent_compression(leaf, fi) !=
 281                     BTRFS_COMPRESS_NONE)
 282                         return 0;
 283
 284                 /* Uncompressed inline extent size must match item size */
 285                 if (unlikely(item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
 286                                           btrfs_file_extent_ram_bytes(leaf, fi))) {
 287                         file_extent_err(leaf, slot,
 288         "invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
 289                                 item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
 290                                 btrfs_file_extent_ram_bytes(leaf, fi));
 291                         return -EUCLEAN;
 292                 }
 293                 return 0;
 294         }
 295
 296         /* Regular or preallocated extent has fixed item size */
 297         if (unlikely(item_size != sizeof(*fi))) {
 298                 file_extent_err(leaf, slot,
 299         "invalid item size for reg/prealloc file extent, have %u expect %zu",
 300                         item_size, sizeof(*fi));
 301                 return -EUCLEAN;
 302         }
 303         if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
 304                      CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
 305                      CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
 306                      CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
 307                      CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize)))
 308                 return -EUCLEAN;
 309
 310         /* Catch extent end overflow */
 311         if (unlikely(check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
 312                                         key->offset, &extent_end))) {
 313                 file_extent_err(leaf, slot,
 314         "extent end overflow, have file offset %llu extent num bytes %llu",
 315                                 key->offset,
 316                                 btrfs_file_extent_num_bytes(leaf, fi));
 317                 return -EUCLEAN;
 318         }
 319
 320         /*
 321          * Check that no two consecutive file extent items, in the same leaf,
 322          * present ranges that overlap each other.
 323          */
 324         if (slot > 0 &&
 325             prev_key->objectid == key->objectid &&
 326             prev_key->type == BTRFS_EXTENT_DATA_KEY) {
 327                 struct btrfs_file_extent_item *prev_fi;
 328                 u64 prev_end;
 329
 330                 prev_fi = btrfs_item_ptr(leaf, slot - 1,
 331                                          struct btrfs_file_extent_item);
 332                 prev_end = file_extent_end(leaf, prev_key, prev_fi);
 333                 if (unlikely(prev_end > key->offset)) {
 334                         file_extent_err(leaf, slot - 1,
 335 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
 336                                         prev_end, key->offset);
 337                         return -EUCLEAN;
 338                 }
 339         }
 340
 341         return 0;
 342 }
 343
 344 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
 345                            int slot, struct btrfs_key *prev_key)
 346 {
 347         struct btrfs_fs_info *fs_info = leaf->fs_info;
 348         u32 sectorsize = fs_info->sectorsize;
 349         const u32 csumsize = fs_info->csum_size;
 350
 351         if (unlikely(key->objectid != BTRFS_EXTENT_CSUM_OBJECTID)) {
 352                 generic_err(leaf, slot,
 353                 "invalid key objectid for csum item, have %llu expect %llu",
 354                         key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
 355                 return -EUCLEAN;
 356         }
 357         if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 358                 generic_err(leaf, slot,
 359         "unaligned key offset for csum item, have %llu should be aligned to %u",
 360                         key->offset, sectorsize);
 361                 return -EUCLEAN;
 362         }
 363         if (unlikely(!IS_ALIGNED(btrfs_item_size(leaf, slot), csumsize))) {
 364                 generic_err(leaf, slot,
 365         "unaligned item size for csum item, have %u should be aligned to %u",
 366                         btrfs_item_size(leaf, slot), csumsize);
 367                 return -EUCLEAN;
 368         }
 369         if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
 370                 u64 prev_csum_end;
 371                 u32 prev_item_size;
 372
 373                 prev_item_size = btrfs_item_size(leaf, slot - 1);
 374                 prev_csum_end = (prev_item_size / csumsize) * sectorsize;
 375                 prev_csum_end += prev_key->offset;
 376                 if (unlikely(prev_csum_end > key->offset)) {
 377                         generic_err(leaf, slot - 1,
 378 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
 379                                     prev_csum_end, key->offset);
 380                         return -EUCLEAN;
 381                 }
 382         }
 383         return 0;
 384 }
 385
 386 /* Inode item error output has the same format as dir_item_err() */
 387 #define inode_item_err(eb, slot, fmt, ...)                      \
 388         dir_item_err(eb, slot, fmt, __VA_ARGS__)
 389
 390 static int check_inode_key(struct extent_buffer *leaf, struct btrfs_key *key,
 391                            int slot)
 392 {
 393         struct btrfs_key item_key;
 394         bool is_inode_item;
 395
 396         btrfs_item_key_to_cpu(leaf, &item_key, slot);
 397         is_inode_item = (item_key.type == BTRFS_INODE_ITEM_KEY);
 398
 399         /* For XATTR_ITEM, location key should be all 0 */
 400         if (item_key.type == BTRFS_XATTR_ITEM_KEY) {
 401                 if (unlikely(key->objectid != 0 || key->type != 0 ||
 402                              key->offset != 0))
 403                         return -EUCLEAN;
 404                 return 0;
 405         }
 406
 407         if (unlikely((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
 408                       key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
 409                      key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
 410                      key->objectid != BTRFS_FREE_INO_OBJECTID)) {
 411                 if (is_inode_item) {
 412                         generic_err(leaf, slot,
 413         "invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
 414                                 key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
 415                                 BTRFS_FIRST_FREE_OBJECTID,
 416                                 BTRFS_LAST_FREE_OBJECTID,
 417                                 BTRFS_FREE_INO_OBJECTID);
 418                 } else {
 419                         dir_item_err(leaf, slot,
 420 "invalid location key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
 421                                 key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
 422                                 BTRFS_FIRST_FREE_OBJECTID,
 423                                 BTRFS_LAST_FREE_OBJECTID,
 424                                 BTRFS_FREE_INO_OBJECTID);
 425                 }
 426                 return -EUCLEAN;
 427         }
 428         if (unlikely(key->offset != 0)) {
 429                 if (is_inode_item)
 430                         inode_item_err(leaf, slot,
 431                                        "invalid key offset: has %llu expect 0",
 432                                        key->offset);
 433                 else
 434                         dir_item_err(leaf, slot,
 435                                 "invalid location key offset:has %llu expect 0",
 436                                 key->offset);
 437                 return -EUCLEAN;
 438         }
 439         return 0;
 440 }
 441
 442 static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
 443                           int slot)
 444 {
 445         struct btrfs_key item_key;
 446         bool is_root_item;
 447
 448         btrfs_item_key_to_cpu(leaf, &item_key, slot);
 449         is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
 450
 451         /*
 452          * Bad rootid for reloc trees.
 453          *
 454          * Reloc trees are only for subvolume trees, other trees only need
 455          * to be COWed to be relocated.
 456          */
 457         if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
 458                      !is_fstree(key->offset))) {
 459                 generic_err(leaf, slot,
 460                 "invalid reloc tree for root %lld, root id is not a subvolume tree",
 461                             key->offset);
 462                 return -EUCLEAN;
 463         }
 464
 465         /* No such tree id */
 466         if (unlikely(key->objectid == 0)) {
 467                 if (is_root_item)
 468                         generic_err(leaf, slot, "invalid root id 0");
 469                 else
 470                         dir_item_err(leaf, slot,
 471                                      "invalid location key root id 0");
 472                 return -EUCLEAN;
 473         }
 474
 475         /* DIR_ITEM/INDEX/INODE_REF is not allowed to point to non-fs trees */
 476         if (unlikely(!is_fstree(key->objectid) && !is_root_item)) {
 477                 dir_item_err(leaf, slot,
 478                 "invalid location key objectid, have %llu expect [%llu, %llu]",
 479                                 key->objectid, BTRFS_FIRST_FREE_OBJECTID,
 480                                 BTRFS_LAST_FREE_OBJECTID);
 481                 return -EUCLEAN;
 482         }
 483
 484         /*
 485          * ROOT_ITEM with non-zero offset means this is a snapshot, created at
 486          * @offset transid.
 487          * Furthermore, for location key in DIR_ITEM, its offset is always -1.
 488          *
 489          * So here we only check offset for reloc tree whose key->offset must
 490          * be a valid tree.
 491          */
 492         if (unlikely(key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
 493                      key->offset == 0)) {
 494                 generic_err(leaf, slot, "invalid root id 0 for reloc tree");
 495                 return -EUCLEAN;
 496         }
 497         return 0;
 498 }
 499
 500 static int check_dir_item(struct extent_buffer *leaf,
 501                           struct btrfs_key *key, struct btrfs_key *prev_key,
 502                           int slot)
 503 {
 504         struct btrfs_fs_info *fs_info = leaf->fs_info;
 505         struct btrfs_dir_item *di;
 506         u32 item_size = btrfs_item_size(leaf, slot);
 507         u32 cur = 0;
 508
 509         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
 510                 return -EUCLEAN;
 511
 512         di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
 513         while (cur < item_size) {
 514                 struct btrfs_key location_key;
 515                 u32 name_len;
 516                 u32 data_len;
 517                 u32 max_name_len;
 518                 u32 total_size;
 519                 u32 name_hash;
 520                 u8 dir_type;
 521                 int ret;
 522
 523                 /* header itself should not cross item boundary */
 524                 if (unlikely(cur + sizeof(*di) > item_size)) {
 525                         dir_item_err(leaf, slot,
 526                 "dir item header crosses item boundary, have %zu boundary %u",
 527                                 cur + sizeof(*di), item_size);
 528                         return -EUCLEAN;
 529                 }
 530
 531                 /* Location key check */
 532                 btrfs_dir_item_key_to_cpu(leaf, di, &location_key);
 533                 if (location_key.type == BTRFS_ROOT_ITEM_KEY) {
 534                         ret = check_root_key(leaf, &location_key, slot);
 535                         if (unlikely(ret < 0))
 536                                 return ret;
 537                 } else if (location_key.type == BTRFS_INODE_ITEM_KEY ||
 538                            location_key.type == 0) {
 539                         ret = check_inode_key(leaf, &location_key, slot);
 540                         if (unlikely(ret < 0))
 541                                 return ret;
 542                 } else {
 543                         dir_item_err(leaf, slot,
 544                         "invalid location key type, have %u, expect %u or %u",
 545                                      location_key.type, BTRFS_ROOT_ITEM_KEY,
 546                                      BTRFS_INODE_ITEM_KEY);
 547                         return -EUCLEAN;
 548                 }
 549
 550                 /* dir type check */
 551                 dir_type = btrfs_dir_ftype(leaf, di);
 552                 if (unlikely(dir_type >= BTRFS_FT_MAX)) {
 553                         dir_item_err(leaf, slot,
 554                         "invalid dir item type, have %u expect [0, %u)",
 555                                 dir_type, BTRFS_FT_MAX);
 556                         return -EUCLEAN;
 557                 }
 558
 559                 if (unlikely(key->type == BTRFS_XATTR_ITEM_KEY &&
 560                              dir_type != BTRFS_FT_XATTR)) {
 561                         dir_item_err(leaf, slot,
 562                 "invalid dir item type for XATTR key, have %u expect %u",
 563                                 dir_type, BTRFS_FT_XATTR);
 564                         return -EUCLEAN;
 565                 }
 566                 if (unlikely(dir_type == BTRFS_FT_XATTR &&
 567                              key->type != BTRFS_XATTR_ITEM_KEY)) {
 568                         dir_item_err(leaf, slot,
 569                         "xattr dir type found for non-XATTR key");
 570                         return -EUCLEAN;
 571                 }
 572                 if (dir_type == BTRFS_FT_XATTR)
 573                         max_name_len = XATTR_NAME_MAX;
 574                 else
 575                         max_name_len = BTRFS_NAME_LEN;
 576
 577                 /* Name/data length check */
 578                 name_len = btrfs_dir_name_len(leaf, di);
 579                 data_len = btrfs_dir_data_len(leaf, di);
 580                 if (unlikely(name_len > max_name_len)) {
 581                         dir_item_err(leaf, slot,
 582                         "dir item name len too long, have %u max %u",
 583                                 name_len, max_name_len);
 584                         return -EUCLEAN;
 585                 }
 586                 if (unlikely(name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info))) {
 587                         dir_item_err(leaf, slot,
 588                         "dir item name and data len too long, have %u max %u",
 589                                 name_len + data_len,
 590                                 BTRFS_MAX_XATTR_SIZE(fs_info));
 591                         return -EUCLEAN;
 592                 }
 593
 594                 if (unlikely(data_len && dir_type != BTRFS_FT_XATTR)) {
 595                         dir_item_err(leaf, slot,
 596                         "dir item with invalid data len, have %u expect 0",
 597                                 data_len);
 598                         return -EUCLEAN;
 599                 }
 600
 601                 total_size = sizeof(*di) + name_len + data_len;
 602
 603                 /* header and name/data should not cross item boundary */
 604                 if (unlikely(cur + total_size > item_size)) {
 605                         dir_item_err(leaf, slot,
 606                 "dir item data crosses item boundary, have %u boundary %u",
 607                                 cur + total_size, item_size);
 608                         return -EUCLEAN;
 609                 }
 610
 611                 /*
 612                  * Special check for XATTR/DIR_ITEM, as key->offset is name
 613                  * hash, should match its name
 614                  */
 615                 if (key->type == BTRFS_DIR_ITEM_KEY ||
 616                     key->type == BTRFS_XATTR_ITEM_KEY) {
 617                         char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
 618
 619                         read_extent_buffer(leaf, namebuf,
 620                                         (unsigned long)(di + 1), name_len);
 621                         name_hash = btrfs_name_hash(namebuf, name_len);
 622                         if (unlikely(key->offset != name_hash)) {
 623                                 dir_item_err(leaf, slot,
 624                 "name hash mismatch with key, have 0x%016x expect 0x%016llx",
 625                                         name_hash, key->offset);
 626                                 return -EUCLEAN;
 627                         }
 628                 }
 629                 cur += total_size;
 630                 di = (struct btrfs_dir_item *)((void *)di + total_size);
 631         }
 632         return 0;
 633 }
 634
 635 __printf(3, 4)
 636 __cold
 637 static void block_group_err(const struct extent_buffer *eb, int slot,
 638                             const char *fmt, ...)
 639 {
 640         const struct btrfs_fs_info *fs_info = eb->fs_info;
 641         struct btrfs_key key;
 642         struct va_format vaf;
 643         va_list args;
 644
 645         btrfs_item_key_to_cpu(eb, &key, slot);
 646         va_start(args, fmt);
 647
 648         vaf.fmt = fmt;
 649         vaf.va = &args;
 650
 651         btrfs_crit(fs_info,
 652         "corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
 653                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
 654                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 655                 key.objectid, key.offset, &vaf);
 656         va_end(args);
 657 }
 658
 659 static int check_block_group_item(struct extent_buffer *leaf,
 660                                   struct btrfs_key *key, int slot)
 661 {
 662         struct btrfs_fs_info *fs_info = leaf->fs_info;
 663         struct btrfs_block_group_item bgi;
 664         u32 item_size = btrfs_item_size(leaf, slot);
 665         u64 chunk_objectid;
 666         u64 flags;
 667         u64 type;
 668
 669         /*
 670          * Here we don't really care about alignment since extent allocator can
 671          * handle it.  We care more about the size.
 672          */
 673         if (unlikely(key->offset == 0)) {
 674                 block_group_err(leaf, slot,
 675                                 "invalid block group size 0");
 676                 return -EUCLEAN;
 677         }
 678
 679         if (unlikely(item_size != sizeof(bgi))) {
 680                 block_group_err(leaf, slot,
 681                         "invalid item size, have %u expect %zu",
 682                                 item_size, sizeof(bgi));
 683                 return -EUCLEAN;
 684         }
 685
 686         read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
 687                            sizeof(bgi));
 688         chunk_objectid = btrfs_stack_block_group_chunk_objectid(&bgi);
 689         if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
 690                 /*
 691                  * We don't init the nr_global_roots until we load the global
 692                  * roots, so this could be 0 at mount time.  If it's 0 we'll
 693                  * just assume we're fine, and later we'll check against our
 694                  * actual value.
 695                  */
 696                 if (unlikely(fs_info->nr_global_roots &&
 697                              chunk_objectid >= fs_info->nr_global_roots)) {
 698                         block_group_err(leaf, slot,
 699         "invalid block group global root id, have %llu, needs to be <= %llu",
 700                                         chunk_objectid,
 701                                         fs_info->nr_global_roots);
 702                         return -EUCLEAN;
 703                 }
 704         } else if (unlikely(chunk_objectid != BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
 705                 block_group_err(leaf, slot,
 706                 "invalid block group chunk objectid, have %llu expect %llu",
 707                                 btrfs_stack_block_group_chunk_objectid(&bgi),
 708                                 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
 709                 return -EUCLEAN;
 710         }
 711
 712         if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
 713                 block_group_err(leaf, slot,
 714                         "invalid block group used, have %llu expect [0, %llu)",
 715                                 btrfs_stack_block_group_used(&bgi), key->offset);
 716                 return -EUCLEAN;
 717         }
 718
 719         flags = btrfs_stack_block_group_flags(&bgi);
 720         if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
 721                 block_group_err(leaf, slot,
 722 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
 723                         flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
 724                         hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
 725                 return -EUCLEAN;
 726         }
 727
 728         type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
 729         if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
 730                      type != BTRFS_BLOCK_GROUP_METADATA &&
 731                      type != BTRFS_BLOCK_GROUP_SYSTEM &&
 732                      type != (BTRFS_BLOCK_GROUP_METADATA |
 733                               BTRFS_BLOCK_GROUP_DATA))) {
 734                 block_group_err(leaf, slot,
 735 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
 736                         type, hweight64(type),
 737                         BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
 738                         BTRFS_BLOCK_GROUP_SYSTEM,
 739                         BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
 740                 return -EUCLEAN;
 741         }
 742         return 0;
 743 }
 744
 745 __printf(4, 5)
 746 __cold
 747 static void chunk_err(const struct extent_buffer *leaf,
 748                       const struct btrfs_chunk *chunk, u64 logical,
 749                       const char *fmt, ...)
 750 {
 751         const struct btrfs_fs_info *fs_info = leaf->fs_info;
 752         bool is_sb;
 753         struct va_format vaf;
 754         va_list args;
 755         int i;
 756         int slot = -1;
 757
 758         /* Only superblock eb is able to have such small offset */
 759         is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
 760
 761         if (!is_sb) {
 762                 /*
 763                  * Get the slot number by iterating through all slots, this
 764                  * would provide better readability.
 765                  */
 766                 for (i = 0; i < btrfs_header_nritems(leaf); i++) {
 767                         if (btrfs_item_ptr_offset(leaf, i) ==
 768                                         (unsigned long)chunk) {
 769                                 slot = i;
 770                                 break;
 771                         }
 772                 }
 773         }
 774         va_start(args, fmt);
 775         vaf.fmt = fmt;
 776         vaf.va = &args;
 777
 778         if (is_sb)
 779                 btrfs_crit(fs_info,
 780                 "corrupt superblock syschunk array: chunk_start=%llu, %pV",
 781                            logical, &vaf);
 782         else
 783                 btrfs_crit(fs_info,
 784         "corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
 785                            BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
 786                            logical, &vaf);
 787         va_end(args);
 788 }
 789
 790 /*
 791  * The common chunk check which could also work on super block sys chunk array.
 792  *
 793  * Return -EUCLEAN if anything is corrupted.
 794  * Return 0 if everything is OK.
 795  */
 796 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
 797                             struct btrfs_chunk *chunk, u64 logical)
 798 {
 799         struct btrfs_fs_info *fs_info = leaf->fs_info;
 800         u64 length;
 801         u64 chunk_end;
 802         u64 stripe_len;
 803         u16 num_stripes;
 804         u16 sub_stripes;
 805         u64 type;
 806         u64 features;
 807         bool mixed = false;
 808         int raid_index;
 809         int nparity;
 810         int ncopies;
 811
 812         length = btrfs_chunk_length(leaf, chunk);
 813         stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
 814         num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
 815         sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
 816         type = btrfs_chunk_type(leaf, chunk);
 817         raid_index = btrfs_bg_flags_to_raid_index(type);
 818         ncopies = btrfs_raid_array[raid_index].ncopies;
 819         nparity = btrfs_raid_array[raid_index].nparity;
 820
 821         if (unlikely(!num_stripes)) {
 822                 chunk_err(leaf, chunk, logical,
 823                           "invalid chunk num_stripes, have %u", num_stripes);
 824                 return -EUCLEAN;
 825         }
 826         if (unlikely(num_stripes < ncopies)) {
 827                 chunk_err(leaf, chunk, logical,
 828                           "invalid chunk num_stripes < ncopies, have %u < %d",
 829                           num_stripes, ncopies);
 830                 return -EUCLEAN;
 831         }
 832         if (unlikely(nparity && num_stripes == nparity)) {
 833                 chunk_err(leaf, chunk, logical,
 834                           "invalid chunk num_stripes == nparity, have %u == %d",
 835                           num_stripes, nparity);
 836                 return -EUCLEAN;
 837         }
 838         if (unlikely(!IS_ALIGNED(logical, fs_info->sectorsize))) {
 839                 chunk_err(leaf, chunk, logical,
 840                 "invalid chunk logical, have %llu should aligned to %u",
 841                           logical, fs_info->sectorsize);
 842                 return -EUCLEAN;
 843         }
 844         if (unlikely(btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize)) {
 845                 chunk_err(leaf, chunk, logical,
 846                           "invalid chunk sectorsize, have %u expect %u",
 847                           btrfs_chunk_sector_size(leaf, chunk),
 848                           fs_info->sectorsize);
 849                 return -EUCLEAN;
 850         }
 851         if (unlikely(!length || !IS_ALIGNED(length, fs_info->sectorsize))) {
 852                 chunk_err(leaf, chunk, logical,
 853                           "invalid chunk length, have %llu", length);
 854                 return -EUCLEAN;
 855         }
 856         if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
 857                 chunk_err(leaf, chunk, logical,
 858 "invalid chunk logical start and length, have logical start %llu length %llu",
 859                           logical, length);
 860                 return -EUCLEAN;
 861         }
 862         if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
 863                 chunk_err(leaf, chunk, logical,
 864                           "invalid chunk stripe length: %llu",
 865                           stripe_len);
 866                 return -EUCLEAN;
 867         }
 868         /*
 869          * We artificially limit the chunk size, so that the number of stripes
 870          * inside a chunk can be fit into a U32.  The current limit (256G) is
 871          * way too large for real world usage anyway, and it's also much larger
 872          * than our existing limit (10G).
 873          *
 874          * Thus it should be a good way to catch obvious bitflips.
 875          */
 876         if (unlikely(length >= btrfs_stripe_nr_to_offset(U32_MAX))) {
 877                 chunk_err(leaf, chunk, logical,
 878                           "chunk length too large: have %llu limit %llu",
 879                           length, btrfs_stripe_nr_to_offset(U32_MAX));
 880                 return -EUCLEAN;
 881         }
 882         if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
 883                               BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
 884                 chunk_err(leaf, chunk, logical,
 885                           "unrecognized chunk type: 0x%llx",
 886                           ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
 887                             BTRFS_BLOCK_GROUP_PROFILE_MASK) &
 888                           btrfs_chunk_type(leaf, chunk));
 889                 return -EUCLEAN;
 890         }
 891
 892         if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
 893                      (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
 894                 chunk_err(leaf, chunk, logical,
 895                 "invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
 896                           type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
 897                 return -EUCLEAN;
 898         }
 899         if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
 900                 chunk_err(leaf, chunk, logical,
 901         "missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
 902                           type, BTRFS_BLOCK_GROUP_TYPE_MASK);
 903                 return -EUCLEAN;
 904         }
 905
 906         if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
 907                      (type & (BTRFS_BLOCK_GROUP_METADATA |
 908                               BTRFS_BLOCK_GROUP_DATA)))) {
 909                 chunk_err(leaf, chunk, logical,
 910                           "system chunk with data or metadata type: 0x%llx",
 911                           type);
 912                 return -EUCLEAN;
 913         }
 914
 915         features = btrfs_super_incompat_flags(fs_info->super_copy);
 916         if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
 917                 mixed = true;
 918
 919         if (!mixed) {
 920                 if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
 921                              (type & BTRFS_BLOCK_GROUP_DATA))) {
 922                         chunk_err(leaf, chunk, logical,
 923                         "mixed chunk type in non-mixed mode: 0x%llx", type);
 924                         return -EUCLEAN;
 925                 }
 926         }
 927
 928         if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
 929                       sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
 930                      (type & BTRFS_BLOCK_GROUP_RAID1 &&
 931                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
 932                      (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
 933                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
 934                      (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
 935                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
 936                      (type & BTRFS_BLOCK_GROUP_RAID5 &&
 937                       num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
 938                      (type & BTRFS_BLOCK_GROUP_RAID6 &&
 939                       num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
 940                      (type & BTRFS_BLOCK_GROUP_DUP &&
 941                       num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
 942                      ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
 943                       num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
 944                 chunk_err(leaf, chunk, logical,
 945                         "invalid num_stripes:sub_stripes %u:%u for profile %llu",
 946                         num_stripes, sub_stripes,
 947                         type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
 948                 return -EUCLEAN;
 949         }
 950
 951         return 0;
 952 }
 953
 954 /*
 955  * Enhanced version of chunk item checker.
 956  *
 957  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
 958  * to work on super block sys_chunk_array which doesn't have full item ptr.
 959  */
 960 static int check_leaf_chunk_item(struct extent_buffer *leaf,
 961                                  struct btrfs_chunk *chunk,
 962                                  struct btrfs_key *key, int slot)
 963 {
 964         int num_stripes;
 965
 966         if (unlikely(btrfs_item_size(leaf, slot) < sizeof(struct btrfs_chunk))) {
 967                 chunk_err(leaf, chunk, key->offset,
 968                         "invalid chunk item size: have %u expect [%zu, %u)",
 969                         btrfs_item_size(leaf, slot),
 970                         sizeof(struct btrfs_chunk),
 971                         BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
 972                 return -EUCLEAN;
 973         }
 974
 975         num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
 976         /* Let btrfs_check_chunk_valid() handle this error type */
 977         if (num_stripes == 0)
 978                 goto out;
 979
 980         if (unlikely(btrfs_chunk_item_size(num_stripes) !=
 981                      btrfs_item_size(leaf, slot))) {
 982                 chunk_err(leaf, chunk, key->offset,
 983                         "invalid chunk item size: have %u expect %lu",
 984                         btrfs_item_size(leaf, slot),
 985                         btrfs_chunk_item_size(num_stripes));
 986                 return -EUCLEAN;
 987         }
 988 out:
 989         return btrfs_check_chunk_valid(leaf, chunk, key->offset);
 990 }
 991
 992 __printf(3, 4)
 993 __cold
 994 static void dev_item_err(const struct extent_buffer *eb, int slot,
 995                          const char *fmt, ...)
 996 {
 997         struct btrfs_key key;
 998         struct va_format vaf;
 999         va_list args;
1000
1001         btrfs_item_key_to_cpu(eb, &key, slot);
1002         va_start(args, fmt);
1003
1004         vaf.fmt = fmt;
1005         vaf.va = &args;
1006
1007         btrfs_crit(eb->fs_info,
1008         "corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
1009                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
1010                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
1011                 key.objectid, &vaf);
1012         va_end(args);
1013 }
1014
1015 static int check_dev_item(struct extent_buffer *leaf,
1016                           struct btrfs_key *key, int slot)
1017 {
1018         struct btrfs_dev_item *ditem;
1019         const u32 item_size = btrfs_item_size(leaf, slot);
1020
1021         if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
1022                 dev_item_err(leaf, slot,
1023                              "invalid objectid: has=%llu expect=%llu",
1024                              key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
1025                 return -EUCLEAN;
1026         }
1027
1028         if (unlikely(item_size != sizeof(*ditem))) {
1029                 dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
1030                              item_size, sizeof(*ditem));
1031                 return -EUCLEAN;
1032         }
1033
1034         ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
1035         if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
1036                 dev_item_err(leaf, slot,
1037                              "devid mismatch: key has=%llu item has=%llu",
1038                              key->offset, btrfs_device_id(leaf, ditem));
1039                 return -EUCLEAN;
1040         }
1041
1042         /*
1043          * For device total_bytes, we don't have reliable way to check it, as
1044          * it can be 0 for device removal. Device size check can only be done
1045          * by dev extents check.
1046          */
1047         if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1048                      btrfs_device_total_bytes(leaf, ditem))) {
1049                 dev_item_err(leaf, slot,
1050                              "invalid bytes used: have %llu expect [0, %llu]",
1051                              btrfs_device_bytes_used(leaf, ditem),
1052                              btrfs_device_total_bytes(leaf, ditem));
1053                 return -EUCLEAN;
1054         }
1055         /*
1056          * Remaining members like io_align/type/gen/dev_group aren't really
1057          * utilized.  Skip them to make later usage of them easier.
1058          */
1059         return 0;
1060 }
1061
1062 static int check_inode_item(struct extent_buffer *leaf,
1063                             struct btrfs_key *key, int slot)
1064 {
1065         struct btrfs_fs_info *fs_info = leaf->fs_info;
1066         struct btrfs_inode_item *iitem;
1067         u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1068         u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1069         const u32 item_size = btrfs_item_size(leaf, slot);
1070         u32 mode;
1071         int ret;
1072         u32 flags;
1073         u32 ro_flags;
1074
1075         ret = check_inode_key(leaf, key, slot);
1076         if (unlikely(ret < 0))
1077                 return ret;
1078
1079         if (unlikely(item_size != sizeof(*iitem))) {
1080                 generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1081                             item_size, sizeof(*iitem));
1082                 return -EUCLEAN;
1083         }
1084
1085         iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1086
1087         /* Here we use super block generation + 1 to handle log tree */
1088         if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1089                 inode_item_err(leaf, slot,
1090                         "invalid inode generation: has %llu expect (0, %llu]",
1091                                btrfs_inode_generation(leaf, iitem),
1092                                super_gen + 1);
1093                 return -EUCLEAN;
1094         }
1095         /* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1096         if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1097                 inode_item_err(leaf, slot,
1098                         "invalid inode transid: has %llu expect [0, %llu]",
1099                                btrfs_inode_transid(leaf, iitem), super_gen + 1);
1100                 return -EUCLEAN;
1101         }
1102
1103         /*
1104          * For size and nbytes it's better not to be too strict, as for dir
1105          * item its size/nbytes can easily get wrong, but doesn't affect
1106          * anything in the fs. So here we skip the check.
1107          */
1108         mode = btrfs_inode_mode(leaf, iitem);
1109         if (unlikely(mode & ~valid_mask)) {
1110                 inode_item_err(leaf, slot,
1111                                "unknown mode bit detected: 0x%x",
1112                                mode & ~valid_mask);
1113                 return -EUCLEAN;
1114         }
1115
1116         /*
1117          * S_IFMT is not bit mapped so we can't completely rely on
1118          * is_power_of_2/has_single_bit_set, but it can save us from checking
1119          * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1120          */
1121         if (!has_single_bit_set(mode & S_IFMT)) {
1122                 if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1123                         inode_item_err(leaf, slot,
1124                         "invalid mode: has 0%o expect valid S_IF* bit(s)",
1125                                        mode & S_IFMT);
1126                         return -EUCLEAN;
1127                 }
1128         }
1129         if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1130                 inode_item_err(leaf, slot,
1131                        "invalid nlink: has %u expect no more than 1 for dir",
1132                         btrfs_inode_nlink(leaf, iitem));
1133                 return -EUCLEAN;
1134         }
1135         btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1136         if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1137                 inode_item_err(leaf, slot,
1138                                "unknown incompat flags detected: 0x%x", flags);
1139                 return -EUCLEAN;
1140         }
1141         if (unlikely(!sb_rdonly(fs_info->sb) &&
1142                      (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1143                 inode_item_err(leaf, slot,
1144                         "unknown ro-compat flags detected on writeable mount: 0x%x",
1145                         ro_flags);
1146                 return -EUCLEAN;
1147         }
1148         return 0;
1149 }
1150
1151 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1152                            int slot)
1153 {
1154         struct btrfs_fs_info *fs_info = leaf->fs_info;
1155         struct btrfs_root_item ri = { 0 };
1156         const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1157                                      BTRFS_ROOT_SUBVOL_DEAD;
1158         int ret;
1159
1160         ret = check_root_key(leaf, key, slot);
1161         if (unlikely(ret < 0))
1162                 return ret;
1163
1164         if (unlikely(btrfs_item_size(leaf, slot) != sizeof(ri) &&
1165                      btrfs_item_size(leaf, slot) !=
1166                      btrfs_legacy_root_item_size())) {
1167                 generic_err(leaf, slot,
1168                             "invalid root item size, have %u expect %zu or %u",
1169                             btrfs_item_size(leaf, slot), sizeof(ri),
1170                             btrfs_legacy_root_item_size());
1171                 return -EUCLEAN;
1172         }
1173
1174         /*
1175          * For legacy root item, the members starting at generation_v2 will be
1176          * all filled with 0.
1177          * And since we allow geneartion_v2 as 0, it will still pass the check.
1178          */
1179         read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1180                            btrfs_item_size(leaf, slot));
1181
1182         /* Generation related */
1183         if (unlikely(btrfs_root_generation(&ri) >
1184                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1185                 generic_err(leaf, slot,
1186                         "invalid root generation, have %llu expect (0, %llu]",
1187                             btrfs_root_generation(&ri),
1188                             btrfs_super_generation(fs_info->super_copy) + 1);
1189                 return -EUCLEAN;
1190         }
1191         if (unlikely(btrfs_root_generation_v2(&ri) >
1192                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1193                 generic_err(leaf, slot,
1194                 "invalid root v2 generation, have %llu expect (0, %llu]",
1195                             btrfs_root_generation_v2(&ri),
1196                             btrfs_super_generation(fs_info->super_copy) + 1);
1197                 return -EUCLEAN;
1198         }
1199         if (unlikely(btrfs_root_last_snapshot(&ri) >
1200                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1201                 generic_err(leaf, slot,
1202                 "invalid root last_snapshot, have %llu expect (0, %llu]",
1203                             btrfs_root_last_snapshot(&ri),
1204                             btrfs_super_generation(fs_info->super_copy) + 1);
1205                 return -EUCLEAN;
1206         }
1207
1208         /* Alignment and level check */
1209         if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1210                 generic_err(leaf, slot,
1211                 "invalid root bytenr, have %llu expect to be aligned to %u",
1212                             btrfs_root_bytenr(&ri), fs_info->sectorsize);
1213                 return -EUCLEAN;
1214         }
1215         if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1216                 generic_err(leaf, slot,
1217                             "invalid root level, have %u expect [0, %u]",
1218                             btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1219                 return -EUCLEAN;
1220         }
1221         if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1222                 generic_err(leaf, slot,
1223                             "invalid root level, have %u expect [0, %u]",
1224                             btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1225                 return -EUCLEAN;
1226         }
1227
1228         /* Flags check */
1229         if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1230                 generic_err(leaf, slot,
1231                             "invalid root flags, have 0x%llx expect mask 0x%llx",
1232                             btrfs_root_flags(&ri), valid_root_flags);
1233                 return -EUCLEAN;
1234         }
1235         return 0;
1236 }
1237
1238 __printf(3,4)
1239 __cold
1240 static void extent_err(const struct extent_buffer *eb, int slot,
1241                        const char *fmt, ...)
1242 {
1243         struct btrfs_key key;
1244         struct va_format vaf;
1245         va_list args;
1246         u64 bytenr;
1247         u64 len;
1248
1249         btrfs_item_key_to_cpu(eb, &key, slot);
1250         bytenr = key.objectid;
1251         if (key.type == BTRFS_METADATA_ITEM_KEY ||
1252             key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1253             key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1254                 len = eb->fs_info->nodesize;
1255         else
1256                 len = key.offset;
1257         va_start(args, fmt);
1258
1259         vaf.fmt = fmt;
1260         vaf.va = &args;
1261
1262         btrfs_crit(eb->fs_info,
1263         "corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1264                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
1265                 eb->start, slot, bytenr, len, &vaf);
1266         va_end(args);
1267 }
1268
1269 static int check_extent_item(struct extent_buffer *leaf,
1270                              struct btrfs_key *key, int slot,
1271                              struct btrfs_key *prev_key)
1272 {
1273         struct btrfs_fs_info *fs_info = leaf->fs_info;
1274         struct btrfs_extent_item *ei;
1275         bool is_tree_block = false;
1276         unsigned long ptr;      /* Current pointer inside inline refs */
1277         unsigned long end;      /* Extent item end */
1278         const u32 item_size = btrfs_item_size(leaf, slot);
1279         u64 flags;
1280         u64 generation;
1281         u64 total_refs;         /* Total refs in btrfs_extent_item */
1282         u64 inline_refs = 0;    /* found total inline refs */
1283
1284         if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1285                      !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1286                 generic_err(leaf, slot,
1287 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1288                 return -EUCLEAN;
1289         }
1290         /* key->objectid is the bytenr for both key types */
1291         if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1292                 generic_err(leaf, slot,
1293                 "invalid key objectid, have %llu expect to be aligned to %u",
1294                            key->objectid, fs_info->sectorsize);
1295                 return -EUCLEAN;
1296         }
1297
1298         /* key->offset is tree level for METADATA_ITEM_KEY */
1299         if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1300                      key->offset >= BTRFS_MAX_LEVEL)) {
1301                 extent_err(leaf, slot,
1302                            "invalid tree level, have %llu expect [0, %u]",
1303                            key->offset, BTRFS_MAX_LEVEL - 1);
1304                 return -EUCLEAN;
1305         }
1306
1307         /*
1308          * EXTENT/METADATA_ITEM consists of:
1309          * 1) One btrfs_extent_item
1310          *    Records the total refs, type and generation of the extent.
1311          *
1312          * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1313          *    Records the first key and level of the tree block.
1314          *
1315          * 2) Zero or more btrfs_extent_inline_ref(s)
1316          *    Each inline ref has one btrfs_extent_inline_ref shows:
1317          *    2.1) The ref type, one of the 4
1318          *         TREE_BLOCK_REF       Tree block only
1319          *         SHARED_BLOCK_REF     Tree block only
1320          *         EXTENT_DATA_REF      Data only
1321          *         SHARED_DATA_REF      Data only
1322          *    2.2) Ref type specific data
1323          *         Either using btrfs_extent_inline_ref::offset, or specific
1324          *         data structure.
1325          */
1326         if (unlikely(item_size < sizeof(*ei))) {
1327                 extent_err(leaf, slot,
1328                            "invalid item size, have %u expect [%zu, %u)",
1329                            item_size, sizeof(*ei),
1330                            BTRFS_LEAF_DATA_SIZE(fs_info));
1331                 return -EUCLEAN;
1332         }
1333         end = item_size + btrfs_item_ptr_offset(leaf, slot);
1334
1335         /* Checks against extent_item */
1336         ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1337         flags = btrfs_extent_flags(leaf, ei);
1338         total_refs = btrfs_extent_refs(leaf, ei);
1339         generation = btrfs_extent_generation(leaf, ei);
1340         if (unlikely(generation >
1341                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1342                 extent_err(leaf, slot,
1343                            "invalid generation, have %llu expect (0, %llu]",
1344                            generation,
1345                            btrfs_super_generation(fs_info->super_copy) + 1);
1346                 return -EUCLEAN;
1347         }
1348         if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1349                                                   BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1350                 extent_err(leaf, slot,
1351                 "invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1352                         flags, BTRFS_EXTENT_FLAG_DATA |
1353                         BTRFS_EXTENT_FLAG_TREE_BLOCK);
1354                 return -EUCLEAN;
1355         }
1356         is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1357         if (is_tree_block) {
1358                 if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1359                              key->offset != fs_info->nodesize)) {
1360                         extent_err(leaf, slot,
1361                                    "invalid extent length, have %llu expect %u",
1362                                    key->offset, fs_info->nodesize);
1363                         return -EUCLEAN;
1364                 }
1365         } else {
1366                 if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1367                         extent_err(leaf, slot,
1368                         "invalid key type, have %u expect %u for data backref",
1369                                    key->type, BTRFS_EXTENT_ITEM_KEY);
1370                         return -EUCLEAN;
1371                 }
1372                 if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1373                         extent_err(leaf, slot,
1374                         "invalid extent length, have %llu expect aligned to %u",
1375                                    key->offset, fs_info->sectorsize);
1376                         return -EUCLEAN;
1377                 }
1378                 if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1379                         extent_err(leaf, slot,
1380                         "invalid extent flag, data has full backref set");
1381                         return -EUCLEAN;
1382                 }
1383         }
1384         ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1385
1386         /* Check the special case of btrfs_tree_block_info */
1387         if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1388                 struct btrfs_tree_block_info *info;
1389
1390                 info = (struct btrfs_tree_block_info *)ptr;
1391                 if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1392                         extent_err(leaf, slot,
1393                         "invalid tree block info level, have %u expect [0, %u]",
1394                                    btrfs_tree_block_level(leaf, info),
1395                                    BTRFS_MAX_LEVEL - 1);
1396                         return -EUCLEAN;
1397                 }
1398                 ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1399         }
1400
1401         /* Check inline refs */
1402         while (ptr < end) {
1403                 struct btrfs_extent_inline_ref *iref;
1404                 struct btrfs_extent_data_ref *dref;
1405                 struct btrfs_shared_data_ref *sref;
1406                 u64 dref_offset;
1407                 u64 inline_offset;
1408                 u8 inline_type;
1409
1410                 if (unlikely(ptr + sizeof(*iref) > end)) {
1411                         extent_err(leaf, slot,
1412 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1413                                    ptr, sizeof(*iref), end);
1414                         return -EUCLEAN;
1415                 }
1416                 iref = (struct btrfs_extent_inline_ref *)ptr;
1417                 inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1418                 inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1419                 if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1420                         extent_err(leaf, slot,
1421 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1422                                    ptr, inline_type, end);
1423                         return -EUCLEAN;
1424                 }
1425
1426                 switch (inline_type) {
1427                 /* inline_offset is subvolid of the owner, no need to check */
1428                 case BTRFS_TREE_BLOCK_REF_KEY:
1429                         inline_refs++;
1430                         break;
1431                 /* Contains parent bytenr */
1432                 case BTRFS_SHARED_BLOCK_REF_KEY:
1433                         if (unlikely(!IS_ALIGNED(inline_offset,
1434                                                  fs_info->sectorsize))) {
1435                                 extent_err(leaf, slot,
1436                 "invalid tree parent bytenr, have %llu expect aligned to %u",
1437                                            inline_offset, fs_info->sectorsize);
1438                                 return -EUCLEAN;
1439                         }
1440                         inline_refs++;
1441                         break;
1442                 /*
1443                  * Contains owner subvolid, owner key objectid, adjusted offset.
1444                  * The only obvious corruption can happen in that offset.
1445                  */
1446                 case BTRFS_EXTENT_DATA_REF_KEY:
1447                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1448                         dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1449                         if (unlikely(!IS_ALIGNED(dref_offset,
1450                                                  fs_info->sectorsize))) {
1451                                 extent_err(leaf, slot,
1452                 "invalid data ref offset, have %llu expect aligned to %u",
1453                                            dref_offset, fs_info->sectorsize);
1454                                 return -EUCLEAN;
1455                         }
1456                         inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1457                         break;
1458                 /* Contains parent bytenr and ref count */
1459                 case BTRFS_SHARED_DATA_REF_KEY:
1460                         sref = (struct btrfs_shared_data_ref *)(iref + 1);
1461                         if (unlikely(!IS_ALIGNED(inline_offset,
1462                                                  fs_info->sectorsize))) {
1463                                 extent_err(leaf, slot,
1464                 "invalid data parent bytenr, have %llu expect aligned to %u",
1465                                            inline_offset, fs_info->sectorsize);
1466                                 return -EUCLEAN;
1467                         }
1468                         inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1469                         break;
1470                 case BTRFS_EXTENT_OWNER_REF_KEY:
1471                         WARN_ON(!btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
1472                         break;
1473                 default:
1474                         extent_err(leaf, slot, "unknown inline ref type: %u",
1475                                    inline_type);
1476                         return -EUCLEAN;
1477                 }
1478                 ptr += btrfs_extent_inline_ref_size(inline_type);
1479         }
1480         /* No padding is allowed */
1481         if (unlikely(ptr != end)) {
1482                 extent_err(leaf, slot,
1483                            "invalid extent item size, padding bytes found");
1484                 return -EUCLEAN;
1485         }
1486
1487         /* Finally, check the inline refs against total refs */
1488         if (unlikely(inline_refs > total_refs)) {
1489                 extent_err(leaf, slot,
1490                         "invalid extent refs, have %llu expect >= inline %llu",
1491                            total_refs, inline_refs);
1492                 return -EUCLEAN;
1493         }
1494
1495         if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1496             (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1497                 u64 prev_end = prev_key->objectid;
1498
1499                 if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1500                         prev_end += fs_info->nodesize;
1501                 else
1502                         prev_end += prev_key->offset;
1503
1504                 if (unlikely(prev_end > key->objectid)) {
1505                         extent_err(leaf, slot,
1506         "previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1507                                    prev_key->objectid, prev_key->type,
1508                                    prev_key->offset, key->objectid, key->type,
1509                                    key->offset);
1510                         return -EUCLEAN;
1511                 }
1512         }
1513
1514         return 0;
1515 }
1516
1517 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1518                                    struct btrfs_key *key, int slot)
1519 {
1520         u32 expect_item_size = 0;
1521
1522         if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1523                 expect_item_size = sizeof(struct btrfs_shared_data_ref);
1524
1525         if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
1526                 generic_err(leaf, slot,
1527                 "invalid item size, have %u expect %u for key type %u",
1528                             btrfs_item_size(leaf, slot),
1529                             expect_item_size, key->type);
1530                 return -EUCLEAN;
1531         }
1532         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1533                 generic_err(leaf, slot,
1534 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1535                             key->objectid, leaf->fs_info->sectorsize);
1536                 return -EUCLEAN;
1537         }
1538         if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1539                      !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1540                 extent_err(leaf, slot,
1541                 "invalid tree parent bytenr, have %llu expect aligned to %u",
1542                            key->offset, leaf->fs_info->sectorsize);
1543                 return -EUCLEAN;
1544         }
1545         return 0;
1546 }
1547
1548 static int check_extent_data_ref(struct extent_buffer *leaf,
1549                                  struct btrfs_key *key, int slot)
1550 {
1551         struct btrfs_extent_data_ref *dref;
1552         unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1553         const unsigned long end = ptr + btrfs_item_size(leaf, slot);
1554
1555         if (unlikely(btrfs_item_size(leaf, slot) % sizeof(*dref) != 0)) {
1556                 generic_err(leaf, slot,
1557         "invalid item size, have %u expect aligned to %zu for key type %u",
1558                             btrfs_item_size(leaf, slot),
1559                             sizeof(*dref), key->type);
1560                 return -EUCLEAN;
1561         }
1562         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1563                 generic_err(leaf, slot,
1564 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1565                             key->objectid, leaf->fs_info->sectorsize);
1566                 return -EUCLEAN;
1567         }
1568         for (; ptr < end; ptr += sizeof(*dref)) {
1569                 u64 offset;
1570
1571                 /*
1572                  * We cannot check the extent_data_ref hash due to possible
1573                  * overflow from the leaf due to hash collisions.
1574                  */
1575                 dref = (struct btrfs_extent_data_ref *)ptr;
1576                 offset = btrfs_extent_data_ref_offset(leaf, dref);
1577                 if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1578                         extent_err(leaf, slot,
1579         "invalid extent data backref offset, have %llu expect aligned to %u",
1580                                    offset, leaf->fs_info->sectorsize);
1581                         return -EUCLEAN;
1582                 }
1583         }
1584         return 0;
1585 }
1586
1587 #define inode_ref_err(eb, slot, fmt, args...)                   \
1588         inode_item_err(eb, slot, fmt, ##args)
1589 static int check_inode_ref(struct extent_buffer *leaf,
1590                            struct btrfs_key *key, struct btrfs_key *prev_key,
1591                            int slot)
1592 {
1593         struct btrfs_inode_ref *iref;
1594         unsigned long ptr;
1595         unsigned long end;
1596
1597         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1598                 return -EUCLEAN;
1599         /* namelen can't be 0, so item_size == sizeof() is also invalid */
1600         if (unlikely(btrfs_item_size(leaf, slot) <= sizeof(*iref))) {
1601                 inode_ref_err(leaf, slot,
1602                         "invalid item size, have %u expect (%zu, %u)",
1603                         btrfs_item_size(leaf, slot),
1604                         sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1605                 return -EUCLEAN;
1606         }
1607
1608         ptr = btrfs_item_ptr_offset(leaf, slot);
1609         end = ptr + btrfs_item_size(leaf, slot);
1610         while (ptr < end) {
1611                 u16 namelen;
1612
1613                 if (unlikely(ptr + sizeof(iref) > end)) {
1614                         inode_ref_err(leaf, slot,
1615                         "inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1616                                 ptr, end, sizeof(iref));
1617                         return -EUCLEAN;
1618                 }
1619
1620                 iref = (struct btrfs_inode_ref *)ptr;
1621                 namelen = btrfs_inode_ref_name_len(leaf, iref);
1622                 if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1623                         inode_ref_err(leaf, slot,
1624                                 "inode ref overflow, ptr %lu end %lu namelen %u",
1625                                 ptr, end, namelen);
1626                         return -EUCLEAN;
1627                 }
1628
1629                 /*
1630                  * NOTE: In theory we should record all found index numbers
1631                  * to find any duplicated indexes, but that will be too time
1632                  * consuming for inodes with too many hard links.
1633                  */
1634                 ptr += sizeof(*iref) + namelen;
1635         }
1636         return 0;
1637 }
1638
1639 static int check_raid_stripe_extent(const struct extent_buffer *leaf,
1640                                     const struct btrfs_key *key, int slot)
1641 {
1642         struct btrfs_stripe_extent *stripe_extent =
1643                 btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
1644
1645         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1646                 generic_err(leaf, slot,
1647 "invalid key objectid for raid stripe extent, have %llu expect aligned to %u",
1648                             key->objectid, leaf->fs_info->sectorsize);
1649                 return -EUCLEAN;
1650         }
1651
1652         if (unlikely(!btrfs_fs_incompat(leaf->fs_info, RAID_STRIPE_TREE))) {
1653                 generic_err(leaf, slot,
1654         "RAID_STRIPE_EXTENT present but RAID_STRIPE_TREE incompat bit unset");
1655                 return -EUCLEAN;
1656         }
1657
1658         switch (btrfs_stripe_extent_encoding(leaf, stripe_extent)) {
1659         case BTRFS_STRIPE_RAID0:
1660         case BTRFS_STRIPE_RAID1:
1661         case BTRFS_STRIPE_DUP:
1662         case BTRFS_STRIPE_RAID10:
1663         case BTRFS_STRIPE_RAID5:
1664         case BTRFS_STRIPE_RAID6:
1665         case BTRFS_STRIPE_RAID1C3:
1666         case BTRFS_STRIPE_RAID1C4:
1667                 break;
1668         default:
1669                 generic_err(leaf, slot, "invalid raid stripe encoding %u",
1670                             btrfs_stripe_extent_encoding(leaf, stripe_extent));
1671                 return -EUCLEAN;
1672         }
1673
1674         return 0;
1675 }
1676
1677 /*
1678  * Common point to switch the item-specific validation.
1679  */
1680 static enum btrfs_tree_block_status check_leaf_item(struct extent_buffer *leaf,
1681                                                     struct btrfs_key *key,
1682                                                     int slot,
1683                                                     struct btrfs_key *prev_key)
1684 {
1685         int ret = 0;
1686         struct btrfs_chunk *chunk;
1687
1688         switch (key->type) {
1689         case BTRFS_EXTENT_DATA_KEY:
1690                 ret = check_extent_data_item(leaf, key, slot, prev_key);
1691                 break;
1692         case BTRFS_EXTENT_CSUM_KEY:
1693                 ret = check_csum_item(leaf, key, slot, prev_key);
1694                 break;
1695         case BTRFS_DIR_ITEM_KEY:
1696         case BTRFS_DIR_INDEX_KEY:
1697         case BTRFS_XATTR_ITEM_KEY:
1698                 ret = check_dir_item(leaf, key, prev_key, slot);
1699                 break;
1700         case BTRFS_INODE_REF_KEY:
1701                 ret = check_inode_ref(leaf, key, prev_key, slot);
1702                 break;
1703         case BTRFS_BLOCK_GROUP_ITEM_KEY:
1704                 ret = check_block_group_item(leaf, key, slot);
1705                 break;
1706         case BTRFS_CHUNK_ITEM_KEY:
1707                 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1708                 ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1709                 break;
1710         case BTRFS_DEV_ITEM_KEY:
1711                 ret = check_dev_item(leaf, key, slot);
1712                 break;
1713         case BTRFS_INODE_ITEM_KEY:
1714                 ret = check_inode_item(leaf, key, slot);
1715                 break;
1716         case BTRFS_ROOT_ITEM_KEY:
1717                 ret = check_root_item(leaf, key, slot);
1718                 break;
1719         case BTRFS_EXTENT_ITEM_KEY:
1720         case BTRFS_METADATA_ITEM_KEY:
1721                 ret = check_extent_item(leaf, key, slot, prev_key);
1722                 break;
1723         case BTRFS_TREE_BLOCK_REF_KEY:
1724         case BTRFS_SHARED_DATA_REF_KEY:
1725         case BTRFS_SHARED_BLOCK_REF_KEY:
1726                 ret = check_simple_keyed_refs(leaf, key, slot);
1727                 break;
1728         case BTRFS_EXTENT_DATA_REF_KEY:
1729                 ret = check_extent_data_ref(leaf, key, slot);
1730                 break;
1731         case BTRFS_RAID_STRIPE_KEY:
1732                 ret = check_raid_stripe_extent(leaf, key, slot);
1733                 break;
1734         }
1735
1736         if (ret)
1737                 return BTRFS_TREE_BLOCK_INVALID_ITEM;
1738         return BTRFS_TREE_BLOCK_CLEAN;
1739 }
1740
1741 enum btrfs_tree_block_status __btrfs_check_leaf(struct extent_buffer *leaf)
1742 {
1743         struct btrfs_fs_info *fs_info = leaf->fs_info;
1744         /* No valid key type is 0, so all key should be larger than this key */
1745         struct btrfs_key prev_key = {0, 0, 0};
1746         struct btrfs_key key;
1747         u32 nritems = btrfs_header_nritems(leaf);
1748         int slot;
1749
1750         if (unlikely(btrfs_header_level(leaf) != 0)) {
1751                 generic_err(leaf, 0,
1752                         "invalid level for leaf, have %d expect 0",
1753                         btrfs_header_level(leaf));
1754                 return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1755         }
1756
1757         /*
1758          * Extent buffers from a relocation tree have a owner field that
1759          * corresponds to the subvolume tree they are based on. So just from an
1760          * extent buffer alone we can not find out what is the id of the
1761          * corresponding subvolume tree, so we can not figure out if the extent
1762          * buffer corresponds to the root of the relocation tree or not. So
1763          * skip this check for relocation trees.
1764          */
1765         if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1766                 u64 owner = btrfs_header_owner(leaf);
1767
1768                 /* These trees must never be empty */
1769                 if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1770                              owner == BTRFS_CHUNK_TREE_OBJECTID ||
1771                              owner == BTRFS_DEV_TREE_OBJECTID ||
1772                              owner == BTRFS_FS_TREE_OBJECTID ||
1773                              owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1774                         generic_err(leaf, 0,
1775                         "invalid root, root %llu must never be empty",
1776                                     owner);
1777                         return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1778                 }
1779
1780                 /* Unknown tree */
1781                 if (unlikely(owner == 0)) {
1782                         generic_err(leaf, 0,
1783                                 "invalid owner, root 0 is not defined");
1784                         return BTRFS_TREE_BLOCK_INVALID_OWNER;
1785                 }
1786
1787                 /* EXTENT_TREE_V2 can have empty extent trees. */
1788                 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1789                         return BTRFS_TREE_BLOCK_CLEAN;
1790
1791                 if (unlikely(owner == BTRFS_EXTENT_TREE_OBJECTID)) {
1792                         generic_err(leaf, 0,
1793                         "invalid root, root %llu must never be empty",
1794                                     owner);
1795                         return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1796                 }
1797
1798                 return BTRFS_TREE_BLOCK_CLEAN;
1799         }
1800
1801         if (unlikely(nritems == 0))
1802                 return BTRFS_TREE_BLOCK_CLEAN;
1803
1804         /*
1805          * Check the following things to make sure this is a good leaf, and
1806          * leaf users won't need to bother with similar sanity checks:
1807          *
1808          * 1) key ordering
1809          * 2) item offset and size
1810          *    No overlap, no hole, all inside the leaf.
1811          * 3) item content
1812          *    If possible, do comprehensive sanity check.
1813          *    NOTE: All checks must only rely on the item data itself.
1814          */
1815         for (slot = 0; slot < nritems; slot++) {
1816                 u32 item_end_expected;
1817                 u64 item_data_end;
1818
1819                 btrfs_item_key_to_cpu(leaf, &key, slot);
1820
1821                 /* Make sure the keys are in the right order */
1822                 if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
1823                         generic_err(leaf, slot,
1824         "bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1825                                 prev_key.objectid, prev_key.type,
1826                                 prev_key.offset, key.objectid, key.type,
1827                                 key.offset);
1828                         return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
1829                 }
1830
1831                 item_data_end = (u64)btrfs_item_offset(leaf, slot) +
1832                                 btrfs_item_size(leaf, slot);
1833                 /*
1834                  * Make sure the offset and ends are right, remember that the
1835                  * item data starts at the end of the leaf and grows towards the
1836                  * front.
1837                  */
1838                 if (slot == 0)
1839                         item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1840                 else
1841                         item_end_expected = btrfs_item_offset(leaf,
1842                                                                  slot - 1);
1843                 if (unlikely(item_data_end != item_end_expected)) {
1844                         generic_err(leaf, slot,
1845                                 "unexpected item end, have %llu expect %u",
1846                                 item_data_end, item_end_expected);
1847                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1848                 }
1849
1850                 /*
1851                  * Check to make sure that we don't point outside of the leaf,
1852                  * just in case all the items are consistent to each other, but
1853                  * all point outside of the leaf.
1854                  */
1855                 if (unlikely(item_data_end > BTRFS_LEAF_DATA_SIZE(fs_info))) {
1856                         generic_err(leaf, slot,
1857                         "slot end outside of leaf, have %llu expect range [0, %u]",
1858                                 item_data_end, BTRFS_LEAF_DATA_SIZE(fs_info));
1859                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1860                 }
1861
1862                 /* Also check if the item pointer overlaps with btrfs item. */
1863                 if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
1864                              btrfs_item_nr_offset(leaf, slot) + sizeof(struct btrfs_item))) {
1865                         generic_err(leaf, slot,
1866                 "slot overlaps with its data, item end %lu data start %lu",
1867                                 btrfs_item_nr_offset(leaf, slot) +
1868                                 sizeof(struct btrfs_item),
1869                                 btrfs_item_ptr_offset(leaf, slot));
1870                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1871                 }
1872
1873                 /*
1874                  * We only want to do this if WRITTEN is set, otherwise the leaf
1875                  * may be in some intermediate state and won't appear valid.
1876                  */
1877                 if (btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_WRITTEN)) {
1878                         enum btrfs_tree_block_status ret;
1879
1880                         /*
1881                          * Check if the item size and content meet other
1882                          * criteria
1883                          */
1884                         ret = check_leaf_item(leaf, &key, slot, &prev_key);
1885                         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1886                                 return ret;
1887                 }
1888
1889                 prev_key.objectid = key.objectid;
1890                 prev_key.type = key.type;
1891                 prev_key.offset = key.offset;
1892         }
1893
1894         return BTRFS_TREE_BLOCK_CLEAN;
1895 }
1896
1897 int btrfs_check_leaf(struct extent_buffer *leaf)
1898 {
1899         enum btrfs_tree_block_status ret;
1900
1901         ret = __btrfs_check_leaf(leaf);
1902         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1903                 return -EUCLEAN;
1904         return 0;
1905 }
1906 ALLOW_ERROR_INJECTION(btrfs_check_leaf, ERRNO);
1907
1908 enum btrfs_tree_block_status __btrfs_check_node(struct extent_buffer *node)
1909 {
1910         struct btrfs_fs_info *fs_info = node->fs_info;
1911         unsigned long nr = btrfs_header_nritems(node);
1912         struct btrfs_key key, next_key;
1913         int slot;
1914         int level = btrfs_header_level(node);
1915         u64 bytenr;
1916
1917         if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
1918                 generic_err(node, 0,
1919                         "invalid level for node, have %d expect [1, %d]",
1920                         level, BTRFS_MAX_LEVEL - 1);
1921                 return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1922         }
1923         if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
1924                 btrfs_crit(fs_info,
1925 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1926                            btrfs_header_owner(node), node->start,
1927                            nr == 0 ? "small" : "large", nr,
1928                            BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1929                 return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1930         }
1931
1932         for (slot = 0; slot < nr - 1; slot++) {
1933                 bytenr = btrfs_node_blockptr(node, slot);
1934                 btrfs_node_key_to_cpu(node, &key, slot);
1935                 btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1936
1937                 if (unlikely(!bytenr)) {
1938                         generic_err(node, slot,
1939                                 "invalid NULL node pointer");
1940                         return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
1941                 }
1942                 if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
1943                         generic_err(node, slot,
1944                         "unaligned pointer, have %llu should be aligned to %u",
1945                                 bytenr, fs_info->sectorsize);
1946                         return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
1947                 }
1948
1949                 if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
1950                         generic_err(node, slot,
1951         "bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1952                                 key.objectid, key.type, key.offset,
1953                                 next_key.objectid, next_key.type,
1954                                 next_key.offset);
1955                         return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
1956                 }
1957         }
1958         return BTRFS_TREE_BLOCK_CLEAN;
1959 }
1960
1961 int btrfs_check_node(struct extent_buffer *node)
1962 {
1963         enum btrfs_tree_block_status ret;
1964
1965         ret = __btrfs_check_node(node);
1966         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1967                 return -EUCLEAN;
1968         return 0;
1969 }
1970 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
1971
1972 int btrfs_check_eb_owner(const struct extent_buffer *eb, u64 root_owner)
1973 {
1974         const bool is_subvol = is_fstree(root_owner);
1975         const u64 eb_owner = btrfs_header_owner(eb);
1976
1977         /*
1978          * Skip dummy fs, as selftests don't create unique ebs for each dummy
1979          * root.
1980          */
1981         if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &eb->fs_info->fs_state))
1982                 return 0;
1983         /*
1984          * There are several call sites (backref walking, qgroup, and data
1985          * reloc) passing 0 as @root_owner, as they are not holding the
1986          * tree root.  In that case, we can not do a reliable ownership check,
1987          * so just exit.
1988          */
1989         if (root_owner == 0)
1990                 return 0;
1991         /*
1992          * These trees use key.offset as their owner, our callers don't have
1993          * the extra capacity to pass key.offset here.  So we just skip them.
1994          */
1995         if (root_owner == BTRFS_TREE_LOG_OBJECTID ||
1996             root_owner == BTRFS_TREE_RELOC_OBJECTID)
1997                 return 0;
1998
1999         if (!is_subvol) {
2000                 /* For non-subvolume trees, the eb owner should match root owner */
2001                 if (unlikely(root_owner != eb_owner)) {
2002                         btrfs_crit(eb->fs_info,
2003 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect %llu",
2004                                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
2005                                 root_owner, btrfs_header_bytenr(eb), eb_owner,
2006                                 root_owner);
2007                         return -EUCLEAN;
2008                 }
2009                 return 0;
2010         }
2011
2012         /*
2013          * For subvolume trees, owners can mismatch, but they should all belong
2014          * to subvolume trees.
2015          */
2016         if (unlikely(is_subvol != is_fstree(eb_owner))) {
2017                 btrfs_crit(eb->fs_info,
2018 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect [%llu, %llu]",
2019                         btrfs_header_level(eb) == 0 ? "leaf" : "node",
2020                         root_owner, btrfs_header_bytenr(eb), eb_owner,
2021                         BTRFS_FIRST_FREE_OBJECTID, BTRFS_LAST_FREE_OBJECTID);
2022                 return -EUCLEAN;
2023         }
2024         return 0;
2025 }
2026
2027 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
2028                            struct btrfs_key *first_key, u64 parent_transid)
2029 {
2030         struct btrfs_fs_info *fs_info = eb->fs_info;
2031         int found_level;
2032         struct btrfs_key found_key;
2033         int ret;
2034
2035         found_level = btrfs_header_level(eb);
2036         if (found_level != level) {
2037                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2038                      KERN_ERR "BTRFS: tree level check failed\n");
2039                 btrfs_err(fs_info,
2040 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
2041                           eb->start, level, found_level);
2042                 return -EIO;
2043         }
2044
2045         if (!first_key)
2046                 return 0;
2047
2048         /*
2049          * For live tree block (new tree blocks in current transaction),
2050          * we need proper lock context to avoid race, which is impossible here.
2051          * So we only checks tree blocks which is read from disk, whose
2052          * generation <= fs_info->last_trans_committed.
2053          */
2054         if (btrfs_header_generation(eb) > btrfs_get_last_trans_committed(fs_info))
2055                 return 0;
2056
2057         /* We have @first_key, so this @eb must have at least one item */
2058         if (btrfs_header_nritems(eb) == 0) {
2059                 btrfs_err(fs_info,
2060                 "invalid tree nritems, bytenr=%llu nritems=0 expect >0",
2061                           eb->start);
2062                 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
2063                 return -EUCLEAN;
2064         }
2065
2066         if (found_level)
2067                 btrfs_node_key_to_cpu(eb, &found_key, 0);
2068         else
2069                 btrfs_item_key_to_cpu(eb, &found_key, 0);
2070         ret = btrfs_comp_cpu_keys(first_key, &found_key);
2071
2072         if (ret) {
2073                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2074                      KERN_ERR "BTRFS: tree first key check failed\n");
2075                 btrfs_err(fs_info,
2076 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
2077                           eb->start, parent_transid, first_key->objectid,
2078                           first_key->type, first_key->offset,
2079                           found_key.objectid, found_key.type,
2080                           found_key.offset);
2081         }
2082         return ret;
2083 }