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