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
  58static 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
  83static 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
 120static 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
 143static 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 */
 174static 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}
 205static 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
 345static 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
 391static 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
 443static 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
 501static 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
 638static 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
 660static 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
 748static 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 */
 797int 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 */
 961static 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	}
 989out:
 990	return btrfs_check_chunk_valid(leaf, chunk, key->offset);
 991}
 992
 993__printf(3, 4)
 994__cold
 995static 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
1016static 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
1063static 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
1152static 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
1241static 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
1270static 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, btrfs_extent_inline_ref_size(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
1556static 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
1587static 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)
1628static 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
1678static 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 */
1719static 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
1780enum 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
1936int 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}
1945ALLOW_ERROR_INJECTION(btrfs_check_leaf, ERRNO);
1946
1947enum 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
2000int 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}
2009ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
2010
2011int 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
2066int 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}