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 #include "extent-tree.h"
  35
  36 /*
  37  * Error message should follow the following format:
  38  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
  39  *
  40  * @type:       leaf or node
  41  * @identifier: the necessary info to locate the leaf/node.
  42  *              It's recommended to decode key.objecitd/offset if it's
  43  *              meaningful.
  44  * @reason:     describe the error
  45  * @bad_value:  optional, it's recommended to output bad value and its
  46  *              expected value (range).
  47  *
  48  * Since comma is used to separate the components, only space is allowed
  49  * inside each component.
  50  */
  51
  52 /*
  53  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
  54  * Allows callers to customize the output.
  55  */
  56 __printf(3, 4)
  57 __cold
  58 static void generic_err(const struct extent_buffer *eb, int slot,
  59                         const char *fmt, ...)
  60 {
  61         const struct btrfs_fs_info *fs_info = eb->fs_info;
  62         struct va_format vaf;
  63         va_list args;
  64
  65         va_start(args, fmt);
  66
  67         vaf.fmt = fmt;
  68         vaf.va = &args;
  69
  70         btrfs_crit(fs_info,
  71                 "corrupt %s: root=%llu block=%llu slot=%d, %pV",
  72                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
  73                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
  74         va_end(args);
  75 }
  76
  77 /*
  78  * Customized reporter for extent data item, since its key objectid and
  79  * offset has its own meaning.
  80  */
  81 __printf(3, 4)
  82 __cold
  83 static void file_extent_err(const struct extent_buffer *eb, int slot,
  84                             const char *fmt, ...)
  85 {
  86         const struct btrfs_fs_info *fs_info = eb->fs_info;
  87         struct btrfs_key key;
  88         struct va_format vaf;
  89         va_list args;
  90
  91         btrfs_item_key_to_cpu(eb, &key, slot);
  92         va_start(args, fmt);
  93
  94         vaf.fmt = fmt;
  95         vaf.va = &args;
  96
  97         btrfs_crit(fs_info,
  98         "corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
  99                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
 100                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 101                 key.objectid, key.offset, &vaf);
 102         va_end(args);
 103 }
 104
 105 /*
 106  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
 107  * Else return 1
 108  */
 109 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)                     \
 110 ({                                                                            \
 111         if (unlikely(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)),      \
 112                                  (alignment))))                               \
 113                 file_extent_err((leaf), (slot),                               \
 114         "invalid %s for file extent, have %llu, should be aligned to %u",     \
 115                         (#name), btrfs_file_extent_##name((leaf), (fi)),      \
 116                         (alignment));                                         \
 117         (!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
 118 })
 119
 120 static u64 file_extent_end(struct extent_buffer *leaf,
 121                            struct btrfs_key *key,
 122                            struct btrfs_file_extent_item *extent)
 123 {
 124         u64 end;
 125         u64 len;
 126
 127         if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
 128                 len = btrfs_file_extent_ram_bytes(leaf, extent);
 129                 end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
 130         } else {
 131                 len = btrfs_file_extent_num_bytes(leaf, extent);
 132                 end = key->offset + len;
 133         }
 134         return end;
 135 }
 136
 137 /*
 138  * Customized report for dir_item, the only new important information is
 139  * key->objectid, which represents inode number
 140  */
 141 __printf(3, 4)
 142 __cold
 143 static void dir_item_err(const struct extent_buffer *eb, int slot,
 144                          const char *fmt, ...)
 145 {
 146         const struct btrfs_fs_info *fs_info = eb->fs_info;
 147         struct btrfs_key key;
 148         struct va_format vaf;
 149         va_list args;
 150
 151         btrfs_item_key_to_cpu(eb, &key, slot);
 152         va_start(args, fmt);
 153
 154         vaf.fmt = fmt;
 155         vaf.va = &args;
 156
 157         btrfs_crit(fs_info,
 158                 "corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
 159                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
 160                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 161                 key.objectid, &vaf);
 162         va_end(args);
 163 }
 164
 165 /*
 166  * This functions checks prev_key->objectid, to ensure current key and prev_key
 167  * share the same objectid as inode number.
 168  *
 169  * This is to detect missing INODE_ITEM in subvolume trees.
 170  *
 171  * Return true if everything is OK or we don't need to check.
 172  * Return false if anything is wrong.
 173  */
 174 static bool check_prev_ino(struct extent_buffer *leaf,
 175                            struct btrfs_key *key, int slot,
 176                            struct btrfs_key *prev_key)
 177 {
 178         /* No prev key, skip check */
 179         if (slot == 0)
 180                 return true;
 181
 182         /* Only these key->types needs to be checked */
 183         ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
 184                key->type == BTRFS_INODE_REF_KEY ||
 185                key->type == BTRFS_DIR_INDEX_KEY ||
 186                key->type == BTRFS_DIR_ITEM_KEY ||
 187                key->type == BTRFS_EXTENT_DATA_KEY);
 188
 189         /*
 190          * Only subvolume trees along with their reloc trees need this check.
 191          * Things like log tree doesn't follow this ino requirement.
 192          */
 193         if (!is_fstree(btrfs_header_owner(leaf)))
 194                 return true;
 195
 196         if (key->objectid == prev_key->objectid)
 197                 return true;
 198
 199         /* Error found */
 200         dir_item_err(leaf, slot,
 201                 "invalid previous key objectid, have %llu expect %llu",
 202                 prev_key->objectid, key->objectid);
 203         return false;
 204 }
 205 static int check_extent_data_item(struct extent_buffer *leaf,
 206                                   struct btrfs_key *key, int slot,
 207                                   struct btrfs_key *prev_key)
 208 {
 209         struct btrfs_fs_info *fs_info = leaf->fs_info;
 210         struct btrfs_file_extent_item *fi;
 211         u32 sectorsize = fs_info->sectorsize;
 212         u32 item_size = btrfs_item_size(leaf, slot);
 213         u64 extent_end;
 214
 215         if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 216                 file_extent_err(leaf, slot,
 217 "unaligned file_offset for file extent, have %llu should be aligned to %u",
 218                         key->offset, sectorsize);
 219                 return -EUCLEAN;
 220         }
 221
 222         /*
 223          * Previous key must have the same key->objectid (ino).
 224          * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
 225          * But if objectids mismatch, it means we have a missing
 226          * INODE_ITEM.
 227          */
 228         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
 229                 return -EUCLEAN;
 230
 231         fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
 232
 233         /*
 234          * Make sure the item contains at least inline header, so the file
 235          * extent type is not some garbage.
 236          */
 237         if (unlikely(item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START)) {
 238                 file_extent_err(leaf, slot,
 239                                 "invalid item size, have %u expect [%zu, %u)",
 240                                 item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
 241                                 SZ_4K);
 242                 return -EUCLEAN;
 243         }
 244         if (unlikely(btrfs_file_extent_type(leaf, fi) >=
 245                      BTRFS_NR_FILE_EXTENT_TYPES)) {
 246                 file_extent_err(leaf, slot,
 247                 "invalid type for file extent, have %u expect range [0, %u]",
 248                         btrfs_file_extent_type(leaf, fi),
 249                         BTRFS_NR_FILE_EXTENT_TYPES - 1);
 250                 return -EUCLEAN;
 251         }
 252
 253         /*
 254          * Support for new compression/encryption must introduce incompat flag,
 255          * and must be caught in open_ctree().
 256          */
 257         if (unlikely(btrfs_file_extent_compression(leaf, fi) >=
 258                      BTRFS_NR_COMPRESS_TYPES)) {
 259                 file_extent_err(leaf, slot,
 260         "invalid compression for file extent, have %u expect range [0, %u]",
 261                         btrfs_file_extent_compression(leaf, fi),
 262                         BTRFS_NR_COMPRESS_TYPES - 1);
 263                 return -EUCLEAN;
 264         }
 265         if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
 266                 file_extent_err(leaf, slot,
 267                         "invalid encryption for file extent, have %u expect 0",
 268                         btrfs_file_extent_encryption(leaf, fi));
 269                 return -EUCLEAN;
 270         }
 271         if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
 272                 /* Inline extent must have 0 as key offset */
 273                 if (unlikely(key->offset)) {
 274                         file_extent_err(leaf, slot,
 275                 "invalid file_offset for inline file extent, have %llu expect 0",
 276                                 key->offset);
 277                         return -EUCLEAN;
 278                 }
 279
 280                 /* Compressed inline extent has no on-disk size, skip it */
 281                 if (btrfs_file_extent_compression(leaf, fi) !=
 282                     BTRFS_COMPRESS_NONE)
 283                         return 0;
 284
 285                 /* Uncompressed inline extent size must match item size */
 286                 if (unlikely(item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
 287                                           btrfs_file_extent_ram_bytes(leaf, fi))) {
 288                         file_extent_err(leaf, slot,
 289         "invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
 290                                 item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
 291                                 btrfs_file_extent_ram_bytes(leaf, fi));
 292                         return -EUCLEAN;
 293                 }
 294                 return 0;
 295         }
 296
 297         /* Regular or preallocated extent has fixed item size */
 298         if (unlikely(item_size != sizeof(*fi))) {
 299                 file_extent_err(leaf, slot,
 300         "invalid item size for reg/prealloc file extent, have %u expect %zu",
 301                         item_size, sizeof(*fi));
 302                 return -EUCLEAN;
 303         }
 304         if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
 305                      CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
 306                      CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
 307                      CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
 308                      CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize)))
 309                 return -EUCLEAN;
 310
 311         /* Catch extent end overflow */
 312         if (unlikely(check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
 313                                         key->offset, &extent_end))) {
 314                 file_extent_err(leaf, slot,
 315         "extent end overflow, have file offset %llu extent num bytes %llu",
 316                                 key->offset,
 317                                 btrfs_file_extent_num_bytes(leaf, fi));
 318                 return -EUCLEAN;
 319         }
 320
 321         /*
 322          * Check that no two consecutive file extent items, in the same leaf,
 323          * present ranges that overlap each other.
 324          */
 325         if (slot > 0 &&
 326             prev_key->objectid == key->objectid &&
 327             prev_key->type == BTRFS_EXTENT_DATA_KEY) {
 328                 struct btrfs_file_extent_item *prev_fi;
 329                 u64 prev_end;
 330
 331                 prev_fi = btrfs_item_ptr(leaf, slot - 1,
 332                                          struct btrfs_file_extent_item);
 333                 prev_end = file_extent_end(leaf, prev_key, prev_fi);
 334                 if (unlikely(prev_end > key->offset)) {
 335                         file_extent_err(leaf, slot - 1,
 336 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
 337                                         prev_end, key->offset);
 338                         return -EUCLEAN;
 339                 }
 340         }
 341
 342         return 0;
 343 }
 344
 345 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
 346                            int slot, struct btrfs_key *prev_key)
 347 {
 348         struct btrfs_fs_info *fs_info = leaf->fs_info;
 349         u32 sectorsize = fs_info->sectorsize;
 350         const u32 csumsize = fs_info->csum_size;
 351
 352         if (unlikely(key->objectid != BTRFS_EXTENT_CSUM_OBJECTID)) {
 353                 generic_err(leaf, slot,
 354                 "invalid key objectid for csum item, have %llu expect %llu",
 355                         key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
 356                 return -EUCLEAN;
 357         }
 358         if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 359                 generic_err(leaf, slot,
 360         "unaligned key offset for csum item, have %llu should be aligned to %u",
 361                         key->offset, sectorsize);
 362                 return -EUCLEAN;
 363         }
 364         if (unlikely(!IS_ALIGNED(btrfs_item_size(leaf, slot), csumsize))) {
 365                 generic_err(leaf, slot,
 366         "unaligned item size for csum item, have %u should be aligned to %u",
 367                         btrfs_item_size(leaf, slot), csumsize);
 368                 return -EUCLEAN;
 369         }
 370         if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
 371                 u64 prev_csum_end;
 372                 u32 prev_item_size;
 373
 374                 prev_item_size = btrfs_item_size(leaf, slot - 1);
 375                 prev_csum_end = (prev_item_size / csumsize) * sectorsize;
 376                 prev_csum_end += prev_key->offset;
 377                 if (unlikely(prev_csum_end > key->offset)) {
 378                         generic_err(leaf, slot - 1,
 379 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
 380                                     prev_csum_end, key->offset);
 381                         return -EUCLEAN;
 382                 }
 383         }
 384         return 0;
 385 }
 386
 387 /* Inode item error output has the same format as dir_item_err() */
 388 #define inode_item_err(eb, slot, fmt, ...)                      \
 389         dir_item_err(eb, slot, fmt, __VA_ARGS__)
 390
 391 static int check_inode_key(struct extent_buffer *leaf, struct btrfs_key *key,
 392                            int slot)
 393 {
 394         struct btrfs_key item_key;
 395         bool is_inode_item;
 396
 397         btrfs_item_key_to_cpu(leaf, &item_key, slot);
 398         is_inode_item = (item_key.type == BTRFS_INODE_ITEM_KEY);
 399
 400         /* For XATTR_ITEM, location key should be all 0 */
 401         if (item_key.type == BTRFS_XATTR_ITEM_KEY) {
 402                 if (unlikely(key->objectid != 0 || key->type != 0 ||
 403                              key->offset != 0))
 404                         return -EUCLEAN;
 405                 return 0;
 406         }
 407
 408         if (unlikely((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
 409                       key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
 410                      key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
 411                      key->objectid != BTRFS_FREE_INO_OBJECTID)) {
 412                 if (is_inode_item) {
 413                         generic_err(leaf, slot,
 414         "invalid 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                 } else {
 420                         dir_item_err(leaf, slot,
 421 "invalid location key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
 422                                 key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
 423                                 BTRFS_FIRST_FREE_OBJECTID,
 424                                 BTRFS_LAST_FREE_OBJECTID,
 425                                 BTRFS_FREE_INO_OBJECTID);
 426                 }
 427                 return -EUCLEAN;
 428         }
 429         if (unlikely(key->offset != 0)) {
 430                 if (is_inode_item)
 431                         inode_item_err(leaf, slot,
 432                                        "invalid key offset: has %llu expect 0",
 433                                        key->offset);
 434                 else
 435                         dir_item_err(leaf, slot,
 436                                 "invalid location key offset:has %llu expect 0",
 437                                 key->offset);
 438                 return -EUCLEAN;
 439         }
 440         return 0;
 441 }
 442
 443 static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
 444                           int slot)
 445 {
 446         struct btrfs_key item_key;
 447         bool is_root_item;
 448
 449         btrfs_item_key_to_cpu(leaf, &item_key, slot);
 450         is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
 451
 452         /*
 453          * Bad rootid for reloc trees.
 454          *
 455          * Reloc trees are only for subvolume trees, other trees only need
 456          * to be COWed to be relocated.
 457          */
 458         if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
 459                      !is_fstree(key->offset))) {
 460                 generic_err(leaf, slot,
 461                 "invalid reloc tree for root %lld, root id is not a subvolume tree",
 462                             key->offset);
 463                 return -EUCLEAN;
 464         }
 465
 466         /* No such tree id */
 467         if (unlikely(key->objectid == 0)) {
 468                 if (is_root_item)
 469                         generic_err(leaf, slot, "invalid root id 0");
 470                 else
 471                         dir_item_err(leaf, slot,
 472                                      "invalid location key root id 0");
 473                 return -EUCLEAN;
 474         }
 475
 476         /* DIR_ITEM/INDEX/INODE_REF is not allowed to point to non-fs trees */
 477         if (unlikely(!is_fstree(key->objectid) && !is_root_item)) {
 478                 dir_item_err(leaf, slot,
 479                 "invalid location key objectid, have %llu expect [%llu, %llu]",
 480                                 key->objectid, BTRFS_FIRST_FREE_OBJECTID,
 481                                 BTRFS_LAST_FREE_OBJECTID);
 482                 return -EUCLEAN;
 483         }
 484
 485         /*
 486          * ROOT_ITEM with non-zero offset means this is a snapshot, created at
 487          * @offset transid.
 488          * Furthermore, for location key in DIR_ITEM, its offset is always -1.
 489          *
 490          * So here we only check offset for reloc tree whose key->offset must
 491          * be a valid tree.
 492          */
 493         if (unlikely(key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
 494                      key->offset == 0)) {
 495                 generic_err(leaf, slot, "invalid root id 0 for reloc tree");
 496                 return -EUCLEAN;
 497         }
 498         return 0;
 499 }
 500
 501 static int check_dir_item(struct extent_buffer *leaf,
 502                           struct btrfs_key *key, struct btrfs_key *prev_key,
 503                           int slot)
 504 {
 505         struct btrfs_fs_info *fs_info = leaf->fs_info;
 506         struct btrfs_dir_item *di;
 507         u32 item_size = btrfs_item_size(leaf, slot);
 508         u32 cur = 0;
 509
 510         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
 511                 return -EUCLEAN;
 512
 513         di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
 514         while (cur < item_size) {
 515                 struct btrfs_key location_key;
 516                 u32 name_len;
 517                 u32 data_len;
 518                 u32 max_name_len;
 519                 u32 total_size;
 520                 u32 name_hash;
 521                 u8 dir_type;
 522                 int ret;
 523
 524                 /* header itself should not cross item boundary */
 525                 if (unlikely(cur + sizeof(*di) > item_size)) {
 526                         dir_item_err(leaf, slot,
 527                 "dir item header crosses item boundary, have %zu boundary %u",
 528                                 cur + sizeof(*di), item_size);
 529                         return -EUCLEAN;
 530                 }
 531
 532                 /* Location key check */
 533                 btrfs_dir_item_key_to_cpu(leaf, di, &location_key);
 534                 if (location_key.type == BTRFS_ROOT_ITEM_KEY) {
 535                         ret = check_root_key(leaf, &location_key, slot);
 536                         if (unlikely(ret < 0))
 537                                 return ret;
 538                 } else if (location_key.type == BTRFS_INODE_ITEM_KEY ||
 539                            location_key.type == 0) {
 540                         ret = check_inode_key(leaf, &location_key, slot);
 541                         if (unlikely(ret < 0))
 542                                 return ret;
 543                 } else {
 544                         dir_item_err(leaf, slot,
 545                         "invalid location key type, have %u, expect %u or %u",
 546                                      location_key.type, BTRFS_ROOT_ITEM_KEY,
 547                                      BTRFS_INODE_ITEM_KEY);
 548                         return -EUCLEAN;
 549                 }
 550
 551                 /* dir type check */
 552                 dir_type = btrfs_dir_ftype(leaf, di);
 553                 if (unlikely(dir_type >= BTRFS_FT_MAX)) {
 554                         dir_item_err(leaf, slot,
 555                         "invalid dir item type, have %u expect [0, %u)",
 556                                 dir_type, BTRFS_FT_MAX);
 557                         return -EUCLEAN;
 558                 }
 559
 560                 if (unlikely(key->type == BTRFS_XATTR_ITEM_KEY &&
 561                              dir_type != BTRFS_FT_XATTR)) {
 562                         dir_item_err(leaf, slot,
 563                 "invalid dir item type for XATTR key, have %u expect %u",
 564                                 dir_type, BTRFS_FT_XATTR);
 565                         return -EUCLEAN;
 566                 }
 567                 if (unlikely(dir_type == BTRFS_FT_XATTR &&
 568                              key->type != BTRFS_XATTR_ITEM_KEY)) {
 569                         dir_item_err(leaf, slot,
 570                         "xattr dir type found for non-XATTR key");
 571                         return -EUCLEAN;
 572                 }
 573                 if (dir_type == BTRFS_FT_XATTR)
 574                         max_name_len = XATTR_NAME_MAX;
 575                 else
 576                         max_name_len = BTRFS_NAME_LEN;
 577
 578                 /* Name/data length check */
 579                 name_len = btrfs_dir_name_len(leaf, di);
 580                 data_len = btrfs_dir_data_len(leaf, di);
 581                 if (unlikely(name_len > max_name_len)) {
 582                         dir_item_err(leaf, slot,
 583                         "dir item name len too long, have %u max %u",
 584                                 name_len, max_name_len);
 585                         return -EUCLEAN;
 586                 }
 587                 if (unlikely(name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info))) {
 588                         dir_item_err(leaf, slot,
 589                         "dir item name and data len too long, have %u max %u",
 590                                 name_len + data_len,
 591                                 BTRFS_MAX_XATTR_SIZE(fs_info));
 592                         return -EUCLEAN;
 593                 }
 594
 595                 if (unlikely(data_len && dir_type != BTRFS_FT_XATTR)) {
 596                         dir_item_err(leaf, slot,
 597                         "dir item with invalid data len, have %u expect 0",
 598                                 data_len);
 599                         return -EUCLEAN;
 600                 }
 601
 602                 total_size = sizeof(*di) + name_len + data_len;
 603
 604                 /* header and name/data should not cross item boundary */
 605                 if (unlikely(cur + total_size > item_size)) {
 606                         dir_item_err(leaf, slot,
 607                 "dir item data crosses item boundary, have %u boundary %u",
 608                                 cur + total_size, item_size);
 609                         return -EUCLEAN;
 610                 }
 611
 612                 /*
 613                  * Special check for XATTR/DIR_ITEM, as key->offset is name
 614                  * hash, should match its name
 615                  */
 616                 if (key->type == BTRFS_DIR_ITEM_KEY ||
 617                     key->type == BTRFS_XATTR_ITEM_KEY) {
 618                         char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
 619
 620                         read_extent_buffer(leaf, namebuf,
 621                                         (unsigned long)(di + 1), name_len);
 622                         name_hash = btrfs_name_hash(namebuf, name_len);
 623                         if (unlikely(key->offset != name_hash)) {
 624                                 dir_item_err(leaf, slot,
 625                 "name hash mismatch with key, have 0x%016x expect 0x%016llx",
 626                                         name_hash, key->offset);
 627                                 return -EUCLEAN;
 628                         }
 629                 }
 630                 cur += total_size;
 631                 di = (struct btrfs_dir_item *)((void *)di + total_size);
 632         }
 633         return 0;
 634 }
 635
 636 __printf(3, 4)
 637 __cold
 638 static void block_group_err(const struct extent_buffer *eb, int slot,
 639                             const char *fmt, ...)
 640 {
 641         const struct btrfs_fs_info *fs_info = eb->fs_info;
 642         struct btrfs_key key;
 643         struct va_format vaf;
 644         va_list args;
 645
 646         btrfs_item_key_to_cpu(eb, &key, slot);
 647         va_start(args, fmt);
 648
 649         vaf.fmt = fmt;
 650         vaf.va = &args;
 651
 652         btrfs_crit(fs_info,
 653         "corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
 654                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
 655                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
 656                 key.objectid, key.offset, &vaf);
 657         va_end(args);
 658 }
 659
 660 static int check_block_group_item(struct extent_buffer *leaf,
 661                                   struct btrfs_key *key, int slot)
 662 {
 663         struct btrfs_fs_info *fs_info = leaf->fs_info;
 664         struct btrfs_block_group_item bgi;
 665         u32 item_size = btrfs_item_size(leaf, slot);
 666         u64 chunk_objectid;
 667         u64 flags;
 668         u64 type;
 669
 670         /*
 671          * Here we don't really care about alignment since extent allocator can
 672          * handle it.  We care more about the size.
 673          */
 674         if (unlikely(key->offset == 0)) {
 675                 block_group_err(leaf, slot,
 676                                 "invalid block group size 0");
 677                 return -EUCLEAN;
 678         }
 679
 680         if (unlikely(item_size != sizeof(bgi))) {
 681                 block_group_err(leaf, slot,
 682                         "invalid item size, have %u expect %zu",
 683                                 item_size, sizeof(bgi));
 684                 return -EUCLEAN;
 685         }
 686
 687         read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
 688                            sizeof(bgi));
 689         chunk_objectid = btrfs_stack_block_group_chunk_objectid(&bgi);
 690         if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
 691                 /*
 692                  * We don't init the nr_global_roots until we load the global
 693                  * roots, so this could be 0 at mount time.  If it's 0 we'll
 694                  * just assume we're fine, and later we'll check against our
 695                  * actual value.
 696                  */
 697                 if (unlikely(fs_info->nr_global_roots &&
 698                              chunk_objectid >= fs_info->nr_global_roots)) {
 699                         block_group_err(leaf, slot,
 700         "invalid block group global root id, have %llu, needs to be <= %llu",
 701                                         chunk_objectid,
 702                                         fs_info->nr_global_roots);
 703                         return -EUCLEAN;
 704                 }
 705         } else if (unlikely(chunk_objectid != BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
 706                 block_group_err(leaf, slot,
 707                 "invalid block group chunk objectid, have %llu expect %llu",
 708                                 btrfs_stack_block_group_chunk_objectid(&bgi),
 709                                 BTRFS_FIRST_CHUNK_TREE_OBJECTID);
 710                 return -EUCLEAN;
 711         }
 712
 713         if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
 714                 block_group_err(leaf, slot,
 715                         "invalid block group used, have %llu expect [0, %llu)",
 716                                 btrfs_stack_block_group_used(&bgi), key->offset);
 717                 return -EUCLEAN;
 718         }
 719
 720         flags = btrfs_stack_block_group_flags(&bgi);
 721         if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
 722                 block_group_err(leaf, slot,
 723 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
 724                         flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
 725                         hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
 726                 return -EUCLEAN;
 727         }
 728
 729         type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
 730         if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
 731                      type != BTRFS_BLOCK_GROUP_METADATA &&
 732                      type != BTRFS_BLOCK_GROUP_SYSTEM &&
 733                      type != (BTRFS_BLOCK_GROUP_METADATA |
 734                               BTRFS_BLOCK_GROUP_DATA))) {
 735                 block_group_err(leaf, slot,
 736 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
 737                         type, hweight64(type),
 738                         BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
 739                         BTRFS_BLOCK_GROUP_SYSTEM,
 740                         BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
 741                 return -EUCLEAN;
 742         }
 743         return 0;
 744 }
 745
 746 __printf(4, 5)
 747 __cold
 748 static void chunk_err(const struct extent_buffer *leaf,
 749                       const struct btrfs_chunk *chunk, u64 logical,
 750                       const char *fmt, ...)
 751 {
 752         const struct btrfs_fs_info *fs_info = leaf->fs_info;
 753         bool is_sb;
 754         struct va_format vaf;
 755         va_list args;
 756         int i;
 757         int slot = -1;
 758
 759         /* Only superblock eb is able to have such small offset */
 760         is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
 761
 762         if (!is_sb) {
 763                 /*
 764                  * Get the slot number by iterating through all slots, this
 765                  * would provide better readability.
 766                  */
 767                 for (i = 0; i < btrfs_header_nritems(leaf); i++) {
 768                         if (btrfs_item_ptr_offset(leaf, i) ==
 769                                         (unsigned long)chunk) {
 770                                 slot = i;
 771                                 break;
 772                         }
 773                 }
 774         }
 775         va_start(args, fmt);
 776         vaf.fmt = fmt;
 777         vaf.va = &args;
 778
 779         if (is_sb)
 780                 btrfs_crit(fs_info,
 781                 "corrupt superblock syschunk array: chunk_start=%llu, %pV",
 782                            logical, &vaf);
 783         else
 784                 btrfs_crit(fs_info,
 785         "corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
 786                            BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
 787                            logical, &vaf);
 788         va_end(args);
 789 }
 790
 791 /*
 792  * The common chunk check which could also work on super block sys chunk array.
 793  *
 794  * Return -EUCLEAN if anything is corrupted.
 795  * Return 0 if everything is OK.
 796  */
 797 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
 798                             struct btrfs_chunk *chunk, u64 logical)
 799 {
 800         struct btrfs_fs_info *fs_info = leaf->fs_info;
 801         u64 length;
 802         u64 chunk_end;
 803         u64 stripe_len;
 804         u16 num_stripes;
 805         u16 sub_stripes;
 806         u64 type;
 807         u64 features;
 808         bool mixed = false;
 809         int raid_index;
 810         int nparity;
 811         int ncopies;
 812
 813         length = btrfs_chunk_length(leaf, chunk);
 814         stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
 815         num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
 816         sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
 817         type = btrfs_chunk_type(leaf, chunk);
 818         raid_index = btrfs_bg_flags_to_raid_index(type);
 819         ncopies = btrfs_raid_array[raid_index].ncopies;
 820         nparity = btrfs_raid_array[raid_index].nparity;
 821
 822         if (unlikely(!num_stripes)) {
 823                 chunk_err(leaf, chunk, logical,
 824                           "invalid chunk num_stripes, have %u", num_stripes);
 825                 return -EUCLEAN;
 826         }
 827         if (unlikely(num_stripes < ncopies)) {
 828                 chunk_err(leaf, chunk, logical,
 829                           "invalid chunk num_stripes < ncopies, have %u < %d",
 830                           num_stripes, ncopies);
 831                 return -EUCLEAN;
 832         }
 833         if (unlikely(nparity && num_stripes == nparity)) {
 834                 chunk_err(leaf, chunk, logical,
 835                           "invalid chunk num_stripes == nparity, have %u == %d",
 836                           num_stripes, nparity);
 837                 return -EUCLEAN;
 838         }
 839         if (unlikely(!IS_ALIGNED(logical, fs_info->sectorsize))) {
 840                 chunk_err(leaf, chunk, logical,
 841                 "invalid chunk logical, have %llu should aligned to %u",
 842                           logical, fs_info->sectorsize);
 843                 return -EUCLEAN;
 844         }
 845         if (unlikely(btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize)) {
 846                 chunk_err(leaf, chunk, logical,
 847                           "invalid chunk sectorsize, have %u expect %u",
 848                           btrfs_chunk_sector_size(leaf, chunk),
 849                           fs_info->sectorsize);
 850                 return -EUCLEAN;
 851         }
 852         if (unlikely(!length || !IS_ALIGNED(length, fs_info->sectorsize))) {
 853                 chunk_err(leaf, chunk, logical,
 854                           "invalid chunk length, have %llu", length);
 855                 return -EUCLEAN;
 856         }
 857         if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
 858                 chunk_err(leaf, chunk, logical,
 859 "invalid chunk logical start and length, have logical start %llu length %llu",
 860                           logical, length);
 861                 return -EUCLEAN;
 862         }
 863         if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
 864                 chunk_err(leaf, chunk, logical,
 865                           "invalid chunk stripe length: %llu",
 866                           stripe_len);
 867                 return -EUCLEAN;
 868         }
 869         /*
 870          * We artificially limit the chunk size, so that the number of stripes
 871          * inside a chunk can be fit into a U32.  The current limit (256G) is
 872          * way too large for real world usage anyway, and it's also much larger
 873          * than our existing limit (10G).
 874          *
 875          * Thus it should be a good way to catch obvious bitflips.
 876          */
 877         if (unlikely(length >= btrfs_stripe_nr_to_offset(U32_MAX))) {
 878                 chunk_err(leaf, chunk, logical,
 879                           "chunk length too large: have %llu limit %llu",
 880                           length, btrfs_stripe_nr_to_offset(U32_MAX));
 881                 return -EUCLEAN;
 882         }
 883         if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
 884                               BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
 885                 chunk_err(leaf, chunk, logical,
 886                           "unrecognized chunk type: 0x%llx",
 887                           ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
 888                             BTRFS_BLOCK_GROUP_PROFILE_MASK) &
 889                           btrfs_chunk_type(leaf, chunk));
 890                 return -EUCLEAN;
 891         }
 892
 893         if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
 894                      (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
 895                 chunk_err(leaf, chunk, logical,
 896                 "invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
 897                           type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
 898                 return -EUCLEAN;
 899         }
 900         if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
 901                 chunk_err(leaf, chunk, logical,
 902         "missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
 903                           type, BTRFS_BLOCK_GROUP_TYPE_MASK);
 904                 return -EUCLEAN;
 905         }
 906
 907         if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
 908                      (type & (BTRFS_BLOCK_GROUP_METADATA |
 909                               BTRFS_BLOCK_GROUP_DATA)))) {
 910                 chunk_err(leaf, chunk, logical,
 911                           "system chunk with data or metadata type: 0x%llx",
 912                           type);
 913                 return -EUCLEAN;
 914         }
 915
 916         features = btrfs_super_incompat_flags(fs_info->super_copy);
 917         if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
 918                 mixed = true;
 919
 920         if (!mixed) {
 921                 if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
 922                              (type & BTRFS_BLOCK_GROUP_DATA))) {
 923                         chunk_err(leaf, chunk, logical,
 924                         "mixed chunk type in non-mixed mode: 0x%llx", type);
 925                         return -EUCLEAN;
 926                 }
 927         }
 928
 929         if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
 930                       sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
 931                      (type & BTRFS_BLOCK_GROUP_RAID1 &&
 932                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
 933                      (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
 934                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
 935                      (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
 936                       num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
 937                      (type & BTRFS_BLOCK_GROUP_RAID5 &&
 938                       num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
 939                      (type & BTRFS_BLOCK_GROUP_RAID6 &&
 940                       num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
 941                      (type & BTRFS_BLOCK_GROUP_DUP &&
 942                       num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
 943                      ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
 944                       num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
 945                 chunk_err(leaf, chunk, logical,
 946                         "invalid num_stripes:sub_stripes %u:%u for profile %llu",
 947                         num_stripes, sub_stripes,
 948                         type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
 949                 return -EUCLEAN;
 950         }
 951
 952         return 0;
 953 }
 954
 955 /*
 956  * Enhanced version of chunk item checker.
 957  *
 958  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
 959  * to work on super block sys_chunk_array which doesn't have full item ptr.
 960  */
 961 static int check_leaf_chunk_item(struct extent_buffer *leaf,
 962                                  struct btrfs_chunk *chunk,
 963                                  struct btrfs_key *key, int slot)
 964 {
 965         int num_stripes;
 966
 967         if (unlikely(btrfs_item_size(leaf, slot) < sizeof(struct btrfs_chunk))) {
 968                 chunk_err(leaf, chunk, key->offset,
 969                         "invalid chunk item size: have %u expect [%zu, %u)",
 970                         btrfs_item_size(leaf, slot),
 971                         sizeof(struct btrfs_chunk),
 972                         BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
 973                 return -EUCLEAN;
 974         }
 975
 976         num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
 977         /* Let btrfs_check_chunk_valid() handle this error type */
 978         if (num_stripes == 0)
 979                 goto out;
 980
 981         if (unlikely(btrfs_chunk_item_size(num_stripes) !=
 982                      btrfs_item_size(leaf, slot))) {
 983                 chunk_err(leaf, chunk, key->offset,
 984                         "invalid chunk item size: have %u expect %lu",
 985                         btrfs_item_size(leaf, slot),
 986                         btrfs_chunk_item_size(num_stripes));
 987                 return -EUCLEAN;
 988         }
 989 out:
 990         return btrfs_check_chunk_valid(leaf, chunk, key->offset);
 991 }
 992
 993 __printf(3, 4)
 994 __cold
 995 static void dev_item_err(const struct extent_buffer *eb, int slot,
 996                          const char *fmt, ...)
 997 {
 998         struct btrfs_key key;
 999         struct va_format vaf;
1000         va_list args;
1001
1002         btrfs_item_key_to_cpu(eb, &key, slot);
1003         va_start(args, fmt);
1004
1005         vaf.fmt = fmt;
1006         vaf.va = &args;
1007
1008         btrfs_crit(eb->fs_info,
1009         "corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
1010                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
1011                 btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
1012                 key.objectid, &vaf);
1013         va_end(args);
1014 }
1015
1016 static int check_dev_item(struct extent_buffer *leaf,
1017                           struct btrfs_key *key, int slot)
1018 {
1019         struct btrfs_dev_item *ditem;
1020         const u32 item_size = btrfs_item_size(leaf, slot);
1021
1022         if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
1023                 dev_item_err(leaf, slot,
1024                              "invalid objectid: has=%llu expect=%llu",
1025                              key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
1026                 return -EUCLEAN;
1027         }
1028
1029         if (unlikely(item_size != sizeof(*ditem))) {
1030                 dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
1031                              item_size, sizeof(*ditem));
1032                 return -EUCLEAN;
1033         }
1034
1035         ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
1036         if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
1037                 dev_item_err(leaf, slot,
1038                              "devid mismatch: key has=%llu item has=%llu",
1039                              key->offset, btrfs_device_id(leaf, ditem));
1040                 return -EUCLEAN;
1041         }
1042
1043         /*
1044          * For device total_bytes, we don't have reliable way to check it, as
1045          * it can be 0 for device removal. Device size check can only be done
1046          * by dev extents check.
1047          */
1048         if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1049                      btrfs_device_total_bytes(leaf, ditem))) {
1050                 dev_item_err(leaf, slot,
1051                              "invalid bytes used: have %llu expect [0, %llu]",
1052                              btrfs_device_bytes_used(leaf, ditem),
1053                              btrfs_device_total_bytes(leaf, ditem));
1054                 return -EUCLEAN;
1055         }
1056         /*
1057          * Remaining members like io_align/type/gen/dev_group aren't really
1058          * utilized.  Skip them to make later usage of them easier.
1059          */
1060         return 0;
1061 }
1062
1063 static int check_inode_item(struct extent_buffer *leaf,
1064                             struct btrfs_key *key, int slot)
1065 {
1066         struct btrfs_fs_info *fs_info = leaf->fs_info;
1067         struct btrfs_inode_item *iitem;
1068         u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1069         u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1070         const u32 item_size = btrfs_item_size(leaf, slot);
1071         u32 mode;
1072         int ret;
1073         u32 flags;
1074         u32 ro_flags;
1075
1076         ret = check_inode_key(leaf, key, slot);
1077         if (unlikely(ret < 0))
1078                 return ret;
1079
1080         if (unlikely(item_size != sizeof(*iitem))) {
1081                 generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1082                             item_size, sizeof(*iitem));
1083                 return -EUCLEAN;
1084         }
1085
1086         iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1087
1088         /* Here we use super block generation + 1 to handle log tree */
1089         if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1090                 inode_item_err(leaf, slot,
1091                         "invalid inode generation: has %llu expect (0, %llu]",
1092                                btrfs_inode_generation(leaf, iitem),
1093                                super_gen + 1);
1094                 return -EUCLEAN;
1095         }
1096         /* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1097         if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1098                 inode_item_err(leaf, slot,
1099                         "invalid inode transid: has %llu expect [0, %llu]",
1100                                btrfs_inode_transid(leaf, iitem), super_gen + 1);
1101                 return -EUCLEAN;
1102         }
1103
1104         /*
1105          * For size and nbytes it's better not to be too strict, as for dir
1106          * item its size/nbytes can easily get wrong, but doesn't affect
1107          * anything in the fs. So here we skip the check.
1108          */
1109         mode = btrfs_inode_mode(leaf, iitem);
1110         if (unlikely(mode & ~valid_mask)) {
1111                 inode_item_err(leaf, slot,
1112                                "unknown mode bit detected: 0x%x",
1113                                mode & ~valid_mask);
1114                 return -EUCLEAN;
1115         }
1116
1117         /*
1118          * S_IFMT is not bit mapped so we can't completely rely on
1119          * is_power_of_2/has_single_bit_set, but it can save us from checking
1120          * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1121          */
1122         if (!has_single_bit_set(mode & S_IFMT)) {
1123                 if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1124                         inode_item_err(leaf, slot,
1125                         "invalid mode: has 0%o expect valid S_IF* bit(s)",
1126                                        mode & S_IFMT);
1127                         return -EUCLEAN;
1128                 }
1129         }
1130         if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1131                 inode_item_err(leaf, slot,
1132                        "invalid nlink: has %u expect no more than 1 for dir",
1133                         btrfs_inode_nlink(leaf, iitem));
1134                 return -EUCLEAN;
1135         }
1136         btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1137         if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1138                 inode_item_err(leaf, slot,
1139                                "unknown incompat flags detected: 0x%x", flags);
1140                 return -EUCLEAN;
1141         }
1142         if (unlikely(!sb_rdonly(fs_info->sb) &&
1143                      (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1144                 inode_item_err(leaf, slot,
1145                         "unknown ro-compat flags detected on writeable mount: 0x%x",
1146                         ro_flags);
1147                 return -EUCLEAN;
1148         }
1149         return 0;
1150 }
1151
1152 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1153                            int slot)
1154 {
1155         struct btrfs_fs_info *fs_info = leaf->fs_info;
1156         struct btrfs_root_item ri = { 0 };
1157         const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1158                                      BTRFS_ROOT_SUBVOL_DEAD;
1159         int ret;
1160
1161         ret = check_root_key(leaf, key, slot);
1162         if (unlikely(ret < 0))
1163                 return ret;
1164
1165         if (unlikely(btrfs_item_size(leaf, slot) != sizeof(ri) &&
1166                      btrfs_item_size(leaf, slot) !=
1167                      btrfs_legacy_root_item_size())) {
1168                 generic_err(leaf, slot,
1169                             "invalid root item size, have %u expect %zu or %u",
1170                             btrfs_item_size(leaf, slot), sizeof(ri),
1171                             btrfs_legacy_root_item_size());
1172                 return -EUCLEAN;
1173         }
1174
1175         /*
1176          * For legacy root item, the members starting at generation_v2 will be
1177          * all filled with 0.
1178          * And since we allow geneartion_v2 as 0, it will still pass the check.
1179          */
1180         read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1181                            btrfs_item_size(leaf, slot));
1182
1183         /* Generation related */
1184         if (unlikely(btrfs_root_generation(&ri) >
1185                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1186                 generic_err(leaf, slot,
1187                         "invalid root generation, have %llu expect (0, %llu]",
1188                             btrfs_root_generation(&ri),
1189                             btrfs_super_generation(fs_info->super_copy) + 1);
1190                 return -EUCLEAN;
1191         }
1192         if (unlikely(btrfs_root_generation_v2(&ri) >
1193                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1194                 generic_err(leaf, slot,
1195                 "invalid root v2 generation, have %llu expect (0, %llu]",
1196                             btrfs_root_generation_v2(&ri),
1197                             btrfs_super_generation(fs_info->super_copy) + 1);
1198                 return -EUCLEAN;
1199         }
1200         if (unlikely(btrfs_root_last_snapshot(&ri) >
1201                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1202                 generic_err(leaf, slot,
1203                 "invalid root last_snapshot, have %llu expect (0, %llu]",
1204                             btrfs_root_last_snapshot(&ri),
1205                             btrfs_super_generation(fs_info->super_copy) + 1);
1206                 return -EUCLEAN;
1207         }
1208
1209         /* Alignment and level check */
1210         if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1211                 generic_err(leaf, slot,
1212                 "invalid root bytenr, have %llu expect to be aligned to %u",
1213                             btrfs_root_bytenr(&ri), fs_info->sectorsize);
1214                 return -EUCLEAN;
1215         }
1216         if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1217                 generic_err(leaf, slot,
1218                             "invalid root level, have %u expect [0, %u]",
1219                             btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1220                 return -EUCLEAN;
1221         }
1222         if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1223                 generic_err(leaf, slot,
1224                             "invalid root level, have %u expect [0, %u]",
1225                             btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1226                 return -EUCLEAN;
1227         }
1228
1229         /* Flags check */
1230         if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1231                 generic_err(leaf, slot,
1232                             "invalid root flags, have 0x%llx expect mask 0x%llx",
1233                             btrfs_root_flags(&ri), valid_root_flags);
1234                 return -EUCLEAN;
1235         }
1236         return 0;
1237 }
1238
1239 __printf(3,4)
1240 __cold
1241 static void extent_err(const struct extent_buffer *eb, int slot,
1242                        const char *fmt, ...)
1243 {
1244         struct btrfs_key key;
1245         struct va_format vaf;
1246         va_list args;
1247         u64 bytenr;
1248         u64 len;
1249
1250         btrfs_item_key_to_cpu(eb, &key, slot);
1251         bytenr = key.objectid;
1252         if (key.type == BTRFS_METADATA_ITEM_KEY ||
1253             key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1254             key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1255                 len = eb->fs_info->nodesize;
1256         else
1257                 len = key.offset;
1258         va_start(args, fmt);
1259
1260         vaf.fmt = fmt;
1261         vaf.va = &args;
1262
1263         btrfs_crit(eb->fs_info,
1264         "corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1265                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
1266                 eb->start, slot, bytenr, len, &vaf);
1267         va_end(args);
1268 }
1269
1270 static int check_extent_item(struct extent_buffer *leaf,
1271                              struct btrfs_key *key, int slot,
1272                              struct btrfs_key *prev_key)
1273 {
1274         struct btrfs_fs_info *fs_info = leaf->fs_info;
1275         struct btrfs_extent_item *ei;
1276         bool is_tree_block = false;
1277         unsigned long ptr;      /* Current pointer inside inline refs */
1278         unsigned long end;      /* Extent item end */
1279         const u32 item_size = btrfs_item_size(leaf, slot);
1280         u8 last_type = 0;
1281         u64 last_seq = U64_MAX;
1282         u64 flags;
1283         u64 generation;
1284         u64 total_refs;         /* Total refs in btrfs_extent_item */
1285         u64 inline_refs = 0;    /* found total inline refs */
1286
1287         if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1288                      !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1289                 generic_err(leaf, slot,
1290 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1291                 return -EUCLEAN;
1292         }
1293         /* key->objectid is the bytenr for both key types */
1294         if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1295                 generic_err(leaf, slot,
1296                 "invalid key objectid, have %llu expect to be aligned to %u",
1297                            key->objectid, fs_info->sectorsize);
1298                 return -EUCLEAN;
1299         }
1300
1301         /* key->offset is tree level for METADATA_ITEM_KEY */
1302         if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1303                      key->offset >= BTRFS_MAX_LEVEL)) {
1304                 extent_err(leaf, slot,
1305                            "invalid tree level, have %llu expect [0, %u]",
1306                            key->offset, BTRFS_MAX_LEVEL - 1);
1307                 return -EUCLEAN;
1308         }
1309
1310         /*
1311          * EXTENT/METADATA_ITEM consists of:
1312          * 1) One btrfs_extent_item
1313          *    Records the total refs, type and generation of the extent.
1314          *
1315          * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1316          *    Records the first key and level of the tree block.
1317          *
1318          * 2) Zero or more btrfs_extent_inline_ref(s)
1319          *    Each inline ref has one btrfs_extent_inline_ref shows:
1320          *    2.1) The ref type, one of the 4
1321          *         TREE_BLOCK_REF       Tree block only
1322          *         SHARED_BLOCK_REF     Tree block only
1323          *         EXTENT_DATA_REF      Data only
1324          *         SHARED_DATA_REF      Data only
1325          *    2.2) Ref type specific data
1326          *         Either using btrfs_extent_inline_ref::offset, or specific
1327          *         data structure.
1328          *
1329          *    All above inline items should follow the order:
1330          *
1331          *    - All btrfs_extent_inline_ref::type should be in an ascending
1332          *      order
1333          *
1334          *    - Within the same type, the items should follow a descending
1335          *      order by their sequence number. The sequence number is
1336          *      determined by:
1337          *      * btrfs_extent_inline_ref::offset for all types  other than
1338          *        EXTENT_DATA_REF
1339          *      * hash_extent_data_ref() for EXTENT_DATA_REF
1340          */
1341         if (unlikely(item_size < sizeof(*ei))) {
1342                 extent_err(leaf, slot,
1343                            "invalid item size, have %u expect [%zu, %u)",
1344                            item_size, sizeof(*ei),
1345                            BTRFS_LEAF_DATA_SIZE(fs_info));
1346                 return -EUCLEAN;
1347         }
1348         end = item_size + btrfs_item_ptr_offset(leaf, slot);
1349
1350         /* Checks against extent_item */
1351         ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1352         flags = btrfs_extent_flags(leaf, ei);
1353         total_refs = btrfs_extent_refs(leaf, ei);
1354         generation = btrfs_extent_generation(leaf, ei);
1355         if (unlikely(generation >
1356                      btrfs_super_generation(fs_info->super_copy) + 1)) {
1357                 extent_err(leaf, slot,
1358                            "invalid generation, have %llu expect (0, %llu]",
1359                            generation,
1360                            btrfs_super_generation(fs_info->super_copy) + 1);
1361                 return -EUCLEAN;
1362         }
1363         if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1364                                                   BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1365                 extent_err(leaf, slot,
1366                 "invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1367                         flags, BTRFS_EXTENT_FLAG_DATA |
1368                         BTRFS_EXTENT_FLAG_TREE_BLOCK);
1369                 return -EUCLEAN;
1370         }
1371         is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1372         if (is_tree_block) {
1373                 if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1374                              key->offset != fs_info->nodesize)) {
1375                         extent_err(leaf, slot,
1376                                    "invalid extent length, have %llu expect %u",
1377                                    key->offset, fs_info->nodesize);
1378                         return -EUCLEAN;
1379                 }
1380         } else {
1381                 if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1382                         extent_err(leaf, slot,
1383                         "invalid key type, have %u expect %u for data backref",
1384                                    key->type, BTRFS_EXTENT_ITEM_KEY);
1385                         return -EUCLEAN;
1386                 }
1387                 if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1388                         extent_err(leaf, slot,
1389                         "invalid extent length, have %llu expect aligned to %u",
1390                                    key->offset, fs_info->sectorsize);
1391                         return -EUCLEAN;
1392                 }
1393                 if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1394                         extent_err(leaf, slot,
1395                         "invalid extent flag, data has full backref set");
1396                         return -EUCLEAN;
1397                 }
1398         }
1399         ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1400
1401         /* Check the special case of btrfs_tree_block_info */
1402         if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1403                 struct btrfs_tree_block_info *info;
1404
1405                 info = (struct btrfs_tree_block_info *)ptr;
1406                 if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1407                         extent_err(leaf, slot,
1408                         "invalid tree block info level, have %u expect [0, %u]",
1409                                    btrfs_tree_block_level(leaf, info),
1410                                    BTRFS_MAX_LEVEL - 1);
1411                         return -EUCLEAN;
1412                 }
1413                 ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1414         }
1415
1416         /* Check inline refs */
1417         while (ptr < end) {
1418                 struct btrfs_extent_inline_ref *iref;
1419                 struct btrfs_extent_data_ref *dref;
1420                 struct btrfs_shared_data_ref *sref;
1421                 u64 seq;
1422                 u64 dref_offset;
1423                 u64 inline_offset;
1424                 u8 inline_type;
1425
1426                 if (unlikely(ptr + sizeof(*iref) > end)) {
1427                         extent_err(leaf, slot,
1428 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1429                                    ptr, sizeof(*iref), end);
1430                         return -EUCLEAN;
1431                 }
1432                 iref = (struct btrfs_extent_inline_ref *)ptr;
1433                 inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1434                 inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1435                 seq = inline_offset;
1436                 if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1437                         extent_err(leaf, slot,
1438 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1439                                    ptr, inline_type, end);
1440                         return -EUCLEAN;
1441                 }
1442
1443                 switch (inline_type) {
1444                 /* inline_offset is subvolid of the owner, no need to check */
1445                 case BTRFS_TREE_BLOCK_REF_KEY:
1446                         inline_refs++;
1447                         break;
1448                 /* Contains parent bytenr */
1449                 case BTRFS_SHARED_BLOCK_REF_KEY:
1450                         if (unlikely(!IS_ALIGNED(inline_offset,
1451                                                  fs_info->sectorsize))) {
1452                                 extent_err(leaf, slot,
1453                 "invalid tree parent bytenr, have %llu expect aligned to %u",
1454                                            inline_offset, fs_info->sectorsize);
1455                                 return -EUCLEAN;
1456                         }
1457                         inline_refs++;
1458                         break;
1459                 /*
1460                  * Contains owner subvolid, owner key objectid, adjusted offset.
1461                  * The only obvious corruption can happen in that offset.
1462                  */
1463                 case BTRFS_EXTENT_DATA_REF_KEY:
1464                         dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1465                         dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1466                         seq = hash_extent_data_ref(
1467                                         btrfs_extent_data_ref_root(leaf, dref),
1468                                         btrfs_extent_data_ref_objectid(leaf, dref),
1469                                         btrfs_extent_data_ref_offset(leaf, dref));
1470                         if (unlikely(!IS_ALIGNED(dref_offset,
1471                                                  fs_info->sectorsize))) {
1472                                 extent_err(leaf, slot,
1473                 "invalid data ref offset, have %llu expect aligned to %u",
1474                                            dref_offset, fs_info->sectorsize);
1475                                 return -EUCLEAN;
1476                         }
1477                         inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1478                         break;
1479                 /* Contains parent bytenr and ref count */
1480                 case BTRFS_SHARED_DATA_REF_KEY:
1481                         sref = (struct btrfs_shared_data_ref *)(iref + 1);
1482                         if (unlikely(!IS_ALIGNED(inline_offset,
1483                                                  fs_info->sectorsize))) {
1484                                 extent_err(leaf, slot,
1485                 "invalid data parent bytenr, have %llu expect aligned to %u",
1486                                            inline_offset, fs_info->sectorsize);
1487                                 return -EUCLEAN;
1488                         }
1489                         inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1490                         break;
1491                 case BTRFS_EXTENT_OWNER_REF_KEY:
1492                         WARN_ON(!btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
1493                         break;
1494                 default:
1495                         extent_err(leaf, slot, "unknown inline ref type: %u",
1496                                    inline_type);
1497                         return -EUCLEAN;
1498                 }
1499                 if (inline_type < last_type) {
1500                         extent_err(leaf, slot,
1501                                    "inline ref out-of-order: has type %u, prev type %u",
1502                                    inline_type, last_type);
1503                         return -EUCLEAN;
1504                 }
1505                 /* Type changed, allow the sequence starts from U64_MAX again. */
1506                 if (inline_type > last_type)
1507                         last_seq = U64_MAX;
1508                 if (seq > last_seq) {
1509                         extent_err(leaf, slot,
1510 "inline ref out-of-order: has type %u offset %llu seq 0x%llx, prev type %u seq 0x%llx",
1511                                    inline_type, inline_offset, seq,
1512                                    last_type, last_seq);
1513                         return -EUCLEAN;
1514                 }
1515                 last_type = inline_type;
1516                 last_seq = seq;
1517                 ptr += btrfs_extent_inline_ref_size(inline_type);
1518         }
1519         /* No padding is allowed */
1520         if (unlikely(ptr != end)) {
1521                 extent_err(leaf, slot,
1522                            "invalid extent item size, padding bytes found");
1523                 return -EUCLEAN;
1524         }
1525
1526         /* Finally, check the inline refs against total refs */
1527         if (unlikely(inline_refs > total_refs)) {
1528                 extent_err(leaf, slot,
1529                         "invalid extent refs, have %llu expect >= inline %llu",
1530                            total_refs, inline_refs);
1531                 return -EUCLEAN;
1532         }
1533
1534         if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1535             (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1536                 u64 prev_end = prev_key->objectid;
1537
1538                 if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1539                         prev_end += fs_info->nodesize;
1540                 else
1541                         prev_end += prev_key->offset;
1542
1543                 if (unlikely(prev_end > key->objectid)) {
1544                         extent_err(leaf, slot,
1545         "previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1546                                    prev_key->objectid, prev_key->type,
1547                                    prev_key->offset, key->objectid, key->type,
1548                                    key->offset);
1549                         return -EUCLEAN;
1550                 }
1551         }
1552
1553         return 0;
1554 }
1555
1556 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1557                                    struct btrfs_key *key, int slot)
1558 {
1559         u32 expect_item_size = 0;
1560
1561         if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1562                 expect_item_size = sizeof(struct btrfs_shared_data_ref);
1563
1564         if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
1565                 generic_err(leaf, slot,
1566                 "invalid item size, have %u expect %u for key type %u",
1567                             btrfs_item_size(leaf, slot),
1568                             expect_item_size, key->type);
1569                 return -EUCLEAN;
1570         }
1571         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1572                 generic_err(leaf, slot,
1573 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1574                             key->objectid, leaf->fs_info->sectorsize);
1575                 return -EUCLEAN;
1576         }
1577         if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1578                      !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1579                 extent_err(leaf, slot,
1580                 "invalid tree parent bytenr, have %llu expect aligned to %u",
1581                            key->offset, leaf->fs_info->sectorsize);
1582                 return -EUCLEAN;
1583         }
1584         return 0;
1585 }
1586
1587 static int check_extent_data_ref(struct extent_buffer *leaf,
1588                                  struct btrfs_key *key, int slot)
1589 {
1590         struct btrfs_extent_data_ref *dref;
1591         unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1592         const unsigned long end = ptr + btrfs_item_size(leaf, slot);
1593
1594         if (unlikely(btrfs_item_size(leaf, slot) % sizeof(*dref) != 0)) {
1595                 generic_err(leaf, slot,
1596         "invalid item size, have %u expect aligned to %zu for key type %u",
1597                             btrfs_item_size(leaf, slot),
1598                             sizeof(*dref), key->type);
1599                 return -EUCLEAN;
1600         }
1601         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1602                 generic_err(leaf, slot,
1603 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1604                             key->objectid, leaf->fs_info->sectorsize);
1605                 return -EUCLEAN;
1606         }
1607         for (; ptr < end; ptr += sizeof(*dref)) {
1608                 u64 offset;
1609
1610                 /*
1611                  * We cannot check the extent_data_ref hash due to possible
1612                  * overflow from the leaf due to hash collisions.
1613                  */
1614                 dref = (struct btrfs_extent_data_ref *)ptr;
1615                 offset = btrfs_extent_data_ref_offset(leaf, dref);
1616                 if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1617                         extent_err(leaf, slot,
1618         "invalid extent data backref offset, have %llu expect aligned to %u",
1619                                    offset, leaf->fs_info->sectorsize);
1620                         return -EUCLEAN;
1621                 }
1622         }
1623         return 0;
1624 }
1625
1626 #define inode_ref_err(eb, slot, fmt, args...)                   \
1627         inode_item_err(eb, slot, fmt, ##args)
1628 static int check_inode_ref(struct extent_buffer *leaf,
1629                            struct btrfs_key *key, struct btrfs_key *prev_key,
1630                            int slot)
1631 {
1632         struct btrfs_inode_ref *iref;
1633         unsigned long ptr;
1634         unsigned long end;
1635
1636         if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1637                 return -EUCLEAN;
1638         /* namelen can't be 0, so item_size == sizeof() is also invalid */
1639         if (unlikely(btrfs_item_size(leaf, slot) <= sizeof(*iref))) {
1640                 inode_ref_err(leaf, slot,
1641                         "invalid item size, have %u expect (%zu, %u)",
1642                         btrfs_item_size(leaf, slot),
1643                         sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1644                 return -EUCLEAN;
1645         }
1646
1647         ptr = btrfs_item_ptr_offset(leaf, slot);
1648         end = ptr + btrfs_item_size(leaf, slot);
1649         while (ptr < end) {
1650                 u16 namelen;
1651
1652                 if (unlikely(ptr + sizeof(iref) > end)) {
1653                         inode_ref_err(leaf, slot,
1654                         "inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1655                                 ptr, end, sizeof(iref));
1656                         return -EUCLEAN;
1657                 }
1658
1659                 iref = (struct btrfs_inode_ref *)ptr;
1660                 namelen = btrfs_inode_ref_name_len(leaf, iref);
1661                 if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1662                         inode_ref_err(leaf, slot,
1663                                 "inode ref overflow, ptr %lu end %lu namelen %u",
1664                                 ptr, end, namelen);
1665                         return -EUCLEAN;
1666                 }
1667
1668                 /*
1669                  * NOTE: In theory we should record all found index numbers
1670                  * to find any duplicated indexes, but that will be too time
1671                  * consuming for inodes with too many hard links.
1672                  */
1673                 ptr += sizeof(*iref) + namelen;
1674         }
1675         return 0;
1676 }
1677
1678 static int check_raid_stripe_extent(const struct extent_buffer *leaf,
1679                                     const struct btrfs_key *key, int slot)
1680 {
1681         struct btrfs_stripe_extent *stripe_extent =
1682                 btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
1683
1684         if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1685                 generic_err(leaf, slot,
1686 "invalid key objectid for raid stripe extent, have %llu expect aligned to %u",
1687                             key->objectid, leaf->fs_info->sectorsize);
1688                 return -EUCLEAN;
1689         }
1690
1691         if (unlikely(!btrfs_fs_incompat(leaf->fs_info, RAID_STRIPE_TREE))) {
1692                 generic_err(leaf, slot,
1693         "RAID_STRIPE_EXTENT present but RAID_STRIPE_TREE incompat bit unset");
1694                 return -EUCLEAN;
1695         }
1696
1697         switch (btrfs_stripe_extent_encoding(leaf, stripe_extent)) {
1698         case BTRFS_STRIPE_RAID0:
1699         case BTRFS_STRIPE_RAID1:
1700         case BTRFS_STRIPE_DUP:
1701         case BTRFS_STRIPE_RAID10:
1702         case BTRFS_STRIPE_RAID5:
1703         case BTRFS_STRIPE_RAID6:
1704         case BTRFS_STRIPE_RAID1C3:
1705         case BTRFS_STRIPE_RAID1C4:
1706                 break;
1707         default:
1708                 generic_err(leaf, slot, "invalid raid stripe encoding %u",
1709                             btrfs_stripe_extent_encoding(leaf, stripe_extent));
1710                 return -EUCLEAN;
1711         }
1712
1713         return 0;
1714 }
1715
1716 /*
1717  * Common point to switch the item-specific validation.
1718  */
1719 static enum btrfs_tree_block_status check_leaf_item(struct extent_buffer *leaf,
1720                                                     struct btrfs_key *key,
1721                                                     int slot,
1722                                                     struct btrfs_key *prev_key)
1723 {
1724         int ret = 0;
1725         struct btrfs_chunk *chunk;
1726
1727         switch (key->type) {
1728         case BTRFS_EXTENT_DATA_KEY:
1729                 ret = check_extent_data_item(leaf, key, slot, prev_key);
1730                 break;
1731         case BTRFS_EXTENT_CSUM_KEY:
1732                 ret = check_csum_item(leaf, key, slot, prev_key);
1733                 break;
1734         case BTRFS_DIR_ITEM_KEY:
1735         case BTRFS_DIR_INDEX_KEY:
1736         case BTRFS_XATTR_ITEM_KEY:
1737                 ret = check_dir_item(leaf, key, prev_key, slot);
1738                 break;
1739         case BTRFS_INODE_REF_KEY:
1740                 ret = check_inode_ref(leaf, key, prev_key, slot);
1741                 break;
1742         case BTRFS_BLOCK_GROUP_ITEM_KEY:
1743                 ret = check_block_group_item(leaf, key, slot);
1744                 break;
1745         case BTRFS_CHUNK_ITEM_KEY:
1746                 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1747                 ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1748                 break;
1749         case BTRFS_DEV_ITEM_KEY:
1750                 ret = check_dev_item(leaf, key, slot);
1751                 break;
1752         case BTRFS_INODE_ITEM_KEY:
1753                 ret = check_inode_item(leaf, key, slot);
1754                 break;
1755         case BTRFS_ROOT_ITEM_KEY:
1756                 ret = check_root_item(leaf, key, slot);
1757                 break;
1758         case BTRFS_EXTENT_ITEM_KEY:
1759         case BTRFS_METADATA_ITEM_KEY:
1760                 ret = check_extent_item(leaf, key, slot, prev_key);
1761                 break;
1762         case BTRFS_TREE_BLOCK_REF_KEY:
1763         case BTRFS_SHARED_DATA_REF_KEY:
1764         case BTRFS_SHARED_BLOCK_REF_KEY:
1765                 ret = check_simple_keyed_refs(leaf, key, slot);
1766                 break;
1767         case BTRFS_EXTENT_DATA_REF_KEY:
1768                 ret = check_extent_data_ref(leaf, key, slot);
1769                 break;
1770         case BTRFS_RAID_STRIPE_KEY:
1771                 ret = check_raid_stripe_extent(leaf, key, slot);
1772                 break;
1773         }
1774
1775         if (ret)
1776                 return BTRFS_TREE_BLOCK_INVALID_ITEM;
1777         return BTRFS_TREE_BLOCK_CLEAN;
1778 }
1779
1780 enum btrfs_tree_block_status __btrfs_check_leaf(struct extent_buffer *leaf)
1781 {
1782         struct btrfs_fs_info *fs_info = leaf->fs_info;
1783         /* No valid key type is 0, so all key should be larger than this key */
1784         struct btrfs_key prev_key = {0, 0, 0};
1785         struct btrfs_key key;
1786         u32 nritems = btrfs_header_nritems(leaf);
1787         int slot;
1788
1789         if (unlikely(btrfs_header_level(leaf) != 0)) {
1790                 generic_err(leaf, 0,
1791                         "invalid level for leaf, have %d expect 0",
1792                         btrfs_header_level(leaf));
1793                 return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1794         }
1795
1796         /*
1797          * Extent buffers from a relocation tree have a owner field that
1798          * corresponds to the subvolume tree they are based on. So just from an
1799          * extent buffer alone we can not find out what is the id of the
1800          * corresponding subvolume tree, so we can not figure out if the extent
1801          * buffer corresponds to the root of the relocation tree or not. So
1802          * skip this check for relocation trees.
1803          */
1804         if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1805                 u64 owner = btrfs_header_owner(leaf);
1806
1807                 /* These trees must never be empty */
1808                 if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1809                              owner == BTRFS_CHUNK_TREE_OBJECTID ||
1810                              owner == BTRFS_DEV_TREE_OBJECTID ||
1811                              owner == BTRFS_FS_TREE_OBJECTID ||
1812                              owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1813                         generic_err(leaf, 0,
1814                         "invalid root, root %llu must never be empty",
1815                                     owner);
1816                         return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1817                 }
1818
1819                 /* Unknown tree */
1820                 if (unlikely(owner == 0)) {
1821                         generic_err(leaf, 0,
1822                                 "invalid owner, root 0 is not defined");
1823                         return BTRFS_TREE_BLOCK_INVALID_OWNER;
1824                 }
1825
1826                 /* EXTENT_TREE_V2 can have empty extent trees. */
1827                 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1828                         return BTRFS_TREE_BLOCK_CLEAN;
1829
1830                 if (unlikely(owner == BTRFS_EXTENT_TREE_OBJECTID)) {
1831                         generic_err(leaf, 0,
1832                         "invalid root, root %llu must never be empty",
1833                                     owner);
1834                         return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1835                 }
1836
1837                 return BTRFS_TREE_BLOCK_CLEAN;
1838         }
1839
1840         if (unlikely(nritems == 0))
1841                 return BTRFS_TREE_BLOCK_CLEAN;
1842
1843         /*
1844          * Check the following things to make sure this is a good leaf, and
1845          * leaf users won't need to bother with similar sanity checks:
1846          *
1847          * 1) key ordering
1848          * 2) item offset and size
1849          *    No overlap, no hole, all inside the leaf.
1850          * 3) item content
1851          *    If possible, do comprehensive sanity check.
1852          *    NOTE: All checks must only rely on the item data itself.
1853          */
1854         for (slot = 0; slot < nritems; slot++) {
1855                 u32 item_end_expected;
1856                 u64 item_data_end;
1857
1858                 btrfs_item_key_to_cpu(leaf, &key, slot);
1859
1860                 /* Make sure the keys are in the right order */
1861                 if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
1862                         generic_err(leaf, slot,
1863         "bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1864                                 prev_key.objectid, prev_key.type,
1865                                 prev_key.offset, key.objectid, key.type,
1866                                 key.offset);
1867                         return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
1868                 }
1869
1870                 item_data_end = (u64)btrfs_item_offset(leaf, slot) +
1871                                 btrfs_item_size(leaf, slot);
1872                 /*
1873                  * Make sure the offset and ends are right, remember that the
1874                  * item data starts at the end of the leaf and grows towards the
1875                  * front.
1876                  */
1877                 if (slot == 0)
1878                         item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1879                 else
1880                         item_end_expected = btrfs_item_offset(leaf,
1881                                                                  slot - 1);
1882                 if (unlikely(item_data_end != item_end_expected)) {
1883                         generic_err(leaf, slot,
1884                                 "unexpected item end, have %llu expect %u",
1885                                 item_data_end, item_end_expected);
1886                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1887                 }
1888
1889                 /*
1890                  * Check to make sure that we don't point outside of the leaf,
1891                  * just in case all the items are consistent to each other, but
1892                  * all point outside of the leaf.
1893                  */
1894                 if (unlikely(item_data_end > BTRFS_LEAF_DATA_SIZE(fs_info))) {
1895                         generic_err(leaf, slot,
1896                         "slot end outside of leaf, have %llu expect range [0, %u]",
1897                                 item_data_end, BTRFS_LEAF_DATA_SIZE(fs_info));
1898                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1899                 }
1900
1901                 /* Also check if the item pointer overlaps with btrfs item. */
1902                 if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
1903                              btrfs_item_nr_offset(leaf, slot) + sizeof(struct btrfs_item))) {
1904                         generic_err(leaf, slot,
1905                 "slot overlaps with its data, item end %lu data start %lu",
1906                                 btrfs_item_nr_offset(leaf, slot) +
1907                                 sizeof(struct btrfs_item),
1908                                 btrfs_item_ptr_offset(leaf, slot));
1909                         return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1910                 }
1911
1912                 /*
1913                  * We only want to do this if WRITTEN is set, otherwise the leaf
1914                  * may be in some intermediate state and won't appear valid.
1915                  */
1916                 if (btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_WRITTEN)) {
1917                         enum btrfs_tree_block_status ret;
1918
1919                         /*
1920                          * Check if the item size and content meet other
1921                          * criteria
1922                          */
1923                         ret = check_leaf_item(leaf, &key, slot, &prev_key);
1924                         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1925                                 return ret;
1926                 }
1927
1928                 prev_key.objectid = key.objectid;
1929                 prev_key.type = key.type;
1930                 prev_key.offset = key.offset;
1931         }
1932
1933         return BTRFS_TREE_BLOCK_CLEAN;
1934 }
1935
1936 int btrfs_check_leaf(struct extent_buffer *leaf)
1937 {
1938         enum btrfs_tree_block_status ret;
1939
1940         ret = __btrfs_check_leaf(leaf);
1941         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1942                 return -EUCLEAN;
1943         return 0;
1944 }
1945 ALLOW_ERROR_INJECTION(btrfs_check_leaf, ERRNO);
1946
1947 enum btrfs_tree_block_status __btrfs_check_node(struct extent_buffer *node)
1948 {
1949         struct btrfs_fs_info *fs_info = node->fs_info;
1950         unsigned long nr = btrfs_header_nritems(node);
1951         struct btrfs_key key, next_key;
1952         int slot;
1953         int level = btrfs_header_level(node);
1954         u64 bytenr;
1955
1956         if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
1957                 generic_err(node, 0,
1958                         "invalid level for node, have %d expect [1, %d]",
1959                         level, BTRFS_MAX_LEVEL - 1);
1960                 return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1961         }
1962         if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
1963                 btrfs_crit(fs_info,
1964 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1965                            btrfs_header_owner(node), node->start,
1966                            nr == 0 ? "small" : "large", nr,
1967                            BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1968                 return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1969         }
1970
1971         for (slot = 0; slot < nr - 1; slot++) {
1972                 bytenr = btrfs_node_blockptr(node, slot);
1973                 btrfs_node_key_to_cpu(node, &key, slot);
1974                 btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1975
1976                 if (unlikely(!bytenr)) {
1977                         generic_err(node, slot,
1978                                 "invalid NULL node pointer");
1979                         return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
1980                 }
1981                 if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
1982                         generic_err(node, slot,
1983                         "unaligned pointer, have %llu should be aligned to %u",
1984                                 bytenr, fs_info->sectorsize);
1985                         return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
1986                 }
1987
1988                 if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
1989                         generic_err(node, slot,
1990         "bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1991                                 key.objectid, key.type, key.offset,
1992                                 next_key.objectid, next_key.type,
1993                                 next_key.offset);
1994                         return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
1995                 }
1996         }
1997         return BTRFS_TREE_BLOCK_CLEAN;
1998 }
1999
2000 int btrfs_check_node(struct extent_buffer *node)
2001 {
2002         enum btrfs_tree_block_status ret;
2003
2004         ret = __btrfs_check_node(node);
2005         if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
2006                 return -EUCLEAN;
2007         return 0;
2008 }
2009 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
2010
2011 int btrfs_check_eb_owner(const struct extent_buffer *eb, u64 root_owner)
2012 {
2013         const bool is_subvol = is_fstree(root_owner);
2014         const u64 eb_owner = btrfs_header_owner(eb);
2015
2016         /*
2017          * Skip dummy fs, as selftests don't create unique ebs for each dummy
2018          * root.
2019          */
2020         if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &eb->fs_info->fs_state))
2021                 return 0;
2022         /*
2023          * There are several call sites (backref walking, qgroup, and data
2024          * reloc) passing 0 as @root_owner, as they are not holding the
2025          * tree root.  In that case, we can not do a reliable ownership check,
2026          * so just exit.
2027          */
2028         if (root_owner == 0)
2029                 return 0;
2030         /*
2031          * These trees use key.offset as their owner, our callers don't have
2032          * the extra capacity to pass key.offset here.  So we just skip them.
2033          */
2034         if (root_owner == BTRFS_TREE_LOG_OBJECTID ||
2035             root_owner == BTRFS_TREE_RELOC_OBJECTID)
2036                 return 0;
2037
2038         if (!is_subvol) {
2039                 /* For non-subvolume trees, the eb owner should match root owner */
2040                 if (unlikely(root_owner != eb_owner)) {
2041                         btrfs_crit(eb->fs_info,
2042 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect %llu",
2043                                 btrfs_header_level(eb) == 0 ? "leaf" : "node",
2044                                 root_owner, btrfs_header_bytenr(eb), eb_owner,
2045                                 root_owner);
2046                         return -EUCLEAN;
2047                 }
2048                 return 0;
2049         }
2050
2051         /*
2052          * For subvolume trees, owners can mismatch, but they should all belong
2053          * to subvolume trees.
2054          */
2055         if (unlikely(is_subvol != is_fstree(eb_owner))) {
2056                 btrfs_crit(eb->fs_info,
2057 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect [%llu, %llu]",
2058                         btrfs_header_level(eb) == 0 ? "leaf" : "node",
2059                         root_owner, btrfs_header_bytenr(eb), eb_owner,
2060                         BTRFS_FIRST_FREE_OBJECTID, BTRFS_LAST_FREE_OBJECTID);
2061                 return -EUCLEAN;
2062         }
2063         return 0;
2064 }
2065
2066 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
2067                            struct btrfs_key *first_key, u64 parent_transid)
2068 {
2069         struct btrfs_fs_info *fs_info = eb->fs_info;
2070         int found_level;
2071         struct btrfs_key found_key;
2072         int ret;
2073
2074         found_level = btrfs_header_level(eb);
2075         if (found_level != level) {
2076                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2077                      KERN_ERR "BTRFS: tree level check failed\n");
2078                 btrfs_err(fs_info,
2079 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
2080                           eb->start, level, found_level);
2081                 return -EIO;
2082         }
2083
2084         if (!first_key)
2085                 return 0;
2086
2087         /*
2088          * For live tree block (new tree blocks in current transaction),
2089          * we need proper lock context to avoid race, which is impossible here.
2090          * So we only checks tree blocks which is read from disk, whose
2091          * generation <= fs_info->last_trans_committed.
2092          */
2093         if (btrfs_header_generation(eb) > btrfs_get_last_trans_committed(fs_info))
2094                 return 0;
2095
2096         /* We have @first_key, so this @eb must have at least one item */
2097         if (btrfs_header_nritems(eb) == 0) {
2098                 btrfs_err(fs_info,
2099                 "invalid tree nritems, bytenr=%llu nritems=0 expect >0",
2100                           eb->start);
2101                 WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
2102                 return -EUCLEAN;
2103         }
2104
2105         if (found_level)
2106                 btrfs_node_key_to_cpu(eb, &found_key, 0);
2107         else
2108                 btrfs_item_key_to_cpu(eb, &found_key, 0);
2109         ret = btrfs_comp_cpu_keys(first_key, &found_key);
2110
2111         if (ret) {
2112                 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2113                      KERN_ERR "BTRFS: tree first key check failed\n");
2114                 btrfs_err(fs_info,
2115 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
2116                           eb->start, parent_transid, first_key->objectid,
2117                           first_key->type, first_key->offset,
2118                           found_key.objectid, found_key.type,
2119                           found_key.offset);
2120         }
2121         return ret;
2122 }