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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 "extent-tree.h"
33 
34 /*
35  * Error message should follow the following format:
36  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
37  *
38  * @type:	leaf or node
39  * @identifier:	the necessary info to locate the leaf/node.
40  * 		It's recommended to decode key.objecitd/offset if it's
41  * 		meaningful.
42  * @reason:	describe the error
43  * @bad_value:	optional, it's recommended to output bad value and its
44  *		expected value (range).
45  *
46  * Since comma is used to separate the components, only space is allowed
47  * inside each component.
48  */
49 
50 /*
51  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
52  * Allows callers to customize the output.
53  */
54 __printf(3, 4)
55 __cold
generic_err(const struct extent_buffer * eb,int slot,const char * fmt,...)56 static void generic_err(const struct extent_buffer *eb, int slot,
57 			const char *fmt, ...)
58 {
59 	const struct btrfs_fs_info *fs_info = eb->fs_info;
60 	struct va_format vaf;
61 	va_list args;
62 
63 	va_start(args, fmt);
64 
65 	vaf.fmt = fmt;
66 	vaf.va = &args;
67 
68 	btrfs_crit(fs_info,
69 		"corrupt %s: root=%llu block=%llu slot=%d, %pV",
70 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
71 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
72 	va_end(args);
73 }
74 
75 /*
76  * Customized reporter for extent data item, since its key objectid and
77  * offset has its own meaning.
78  */
79 __printf(3, 4)
80 __cold
file_extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)81 static void file_extent_err(const struct extent_buffer *eb, int slot,
82 			    const char *fmt, ...)
83 {
84 	const struct btrfs_fs_info *fs_info = eb->fs_info;
85 	struct btrfs_key key;
86 	struct va_format vaf;
87 	va_list args;
88 
89 	btrfs_item_key_to_cpu(eb, &key, slot);
90 	va_start(args, fmt);
91 
92 	vaf.fmt = fmt;
93 	vaf.va = &args;
94 
95 	btrfs_crit(fs_info,
96 	"corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
97 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
98 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
99 		key.objectid, key.offset, &vaf);
100 	va_end(args);
101 }
102 
103 /*
104  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
105  * Else return 1
106  */
107 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)		      \
108 ({									      \
109 	if (unlikely(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)),      \
110 				 (alignment))))				      \
111 		file_extent_err((leaf), (slot),				      \
112 	"invalid %s for file extent, have %llu, should be aligned to %u",     \
113 			(#name), btrfs_file_extent_##name((leaf), (fi)),      \
114 			(alignment));					      \
115 	(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
116 })
117 
file_extent_end(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_file_extent_item * extent)118 static u64 file_extent_end(struct extent_buffer *leaf,
119 			   struct btrfs_key *key,
120 			   struct btrfs_file_extent_item *extent)
121 {
122 	u64 end;
123 	u64 len;
124 
125 	if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
126 		len = btrfs_file_extent_ram_bytes(leaf, extent);
127 		end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
128 	} else {
129 		len = btrfs_file_extent_num_bytes(leaf, extent);
130 		end = key->offset + len;
131 	}
132 	return end;
133 }
134 
135 /*
136  * Customized report for dir_item, the only new important information is
137  * key->objectid, which represents inode number
138  */
139 __printf(3, 4)
140 __cold
dir_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)141 static void dir_item_err(const struct extent_buffer *eb, int slot,
142 			 const char *fmt, ...)
143 {
144 	const struct btrfs_fs_info *fs_info = eb->fs_info;
145 	struct btrfs_key key;
146 	struct va_format vaf;
147 	va_list args;
148 
149 	btrfs_item_key_to_cpu(eb, &key, slot);
150 	va_start(args, fmt);
151 
152 	vaf.fmt = fmt;
153 	vaf.va = &args;
154 
155 	btrfs_crit(fs_info,
156 		"corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
157 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
158 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
159 		key.objectid, &vaf);
160 	va_end(args);
161 }
162 
163 /*
164  * This functions checks prev_key->objectid, to ensure current key and prev_key
165  * share the same objectid as inode number.
166  *
167  * This is to detect missing INODE_ITEM in subvolume trees.
168  *
169  * Return true if everything is OK or we don't need to check.
170  * Return false if anything is wrong.
171  */
check_prev_ino(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)172 static bool check_prev_ino(struct extent_buffer *leaf,
173 			   struct btrfs_key *key, int slot,
174 			   struct btrfs_key *prev_key)
175 {
176 	/* No prev key, skip check */
177 	if (slot == 0)
178 		return true;
179 
180 	/* Only these key->types needs to be checked */
181 	ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
182 	       key->type == BTRFS_INODE_REF_KEY ||
183 	       key->type == BTRFS_DIR_INDEX_KEY ||
184 	       key->type == BTRFS_DIR_ITEM_KEY ||
185 	       key->type == BTRFS_EXTENT_DATA_KEY);
186 
187 	/*
188 	 * Only subvolume trees along with their reloc trees need this check.
189 	 * Things like log tree doesn't follow this ino requirement.
190 	 */
191 	if (!is_fstree(btrfs_header_owner(leaf)))
192 		return true;
193 
194 	if (key->objectid == prev_key->objectid)
195 		return true;
196 
197 	/* Error found */
198 	dir_item_err(leaf, slot,
199 		"invalid previous key objectid, have %llu expect %llu",
200 		prev_key->objectid, key->objectid);
201 	return false;
202 }
check_extent_data_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)203 static int check_extent_data_item(struct extent_buffer *leaf,
204 				  struct btrfs_key *key, int slot,
205 				  struct btrfs_key *prev_key)
206 {
207 	struct btrfs_fs_info *fs_info = leaf->fs_info;
208 	struct btrfs_file_extent_item *fi;
209 	u32 sectorsize = fs_info->sectorsize;
210 	u32 item_size = btrfs_item_size(leaf, slot);
211 	u64 extent_end;
212 
213 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
214 		file_extent_err(leaf, slot,
215 "unaligned file_offset for file extent, have %llu should be aligned to %u",
216 			key->offset, sectorsize);
217 		return -EUCLEAN;
218 	}
219 
220 	/*
221 	 * Previous key must have the same key->objectid (ino).
222 	 * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
223 	 * But if objectids mismatch, it means we have a missing
224 	 * INODE_ITEM.
225 	 */
226 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
227 		return -EUCLEAN;
228 
229 	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
230 
231 	/*
232 	 * Make sure the item contains at least inline header, so the file
233 	 * extent type is not some garbage.
234 	 */
235 	if (unlikely(item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START)) {
236 		file_extent_err(leaf, slot,
237 				"invalid item size, have %u expect [%zu, %u)",
238 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
239 				SZ_4K);
240 		return -EUCLEAN;
241 	}
242 	if (unlikely(btrfs_file_extent_type(leaf, fi) >=
243 		     BTRFS_NR_FILE_EXTENT_TYPES)) {
244 		file_extent_err(leaf, slot,
245 		"invalid type for file extent, have %u expect range [0, %u]",
246 			btrfs_file_extent_type(leaf, fi),
247 			BTRFS_NR_FILE_EXTENT_TYPES - 1);
248 		return -EUCLEAN;
249 	}
250 
251 	/*
252 	 * Support for new compression/encryption must introduce incompat flag,
253 	 * and must be caught in open_ctree().
254 	 */
255 	if (unlikely(btrfs_file_extent_compression(leaf, fi) >=
256 		     BTRFS_NR_COMPRESS_TYPES)) {
257 		file_extent_err(leaf, slot,
258 	"invalid compression for file extent, have %u expect range [0, %u]",
259 			btrfs_file_extent_compression(leaf, fi),
260 			BTRFS_NR_COMPRESS_TYPES - 1);
261 		return -EUCLEAN;
262 	}
263 	if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
264 		file_extent_err(leaf, slot,
265 			"invalid encryption for file extent, have %u expect 0",
266 			btrfs_file_extent_encryption(leaf, fi));
267 		return -EUCLEAN;
268 	}
269 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
270 		/* Inline extent must have 0 as key offset */
271 		if (unlikely(key->offset)) {
272 			file_extent_err(leaf, slot,
273 		"invalid file_offset for inline file extent, have %llu expect 0",
274 				key->offset);
275 			return -EUCLEAN;
276 		}
277 
278 		/* Compressed inline extent has no on-disk size, skip it */
279 		if (btrfs_file_extent_compression(leaf, fi) !=
280 		    BTRFS_COMPRESS_NONE)
281 			return 0;
282 
283 		/* Uncompressed inline extent size must match item size */
284 		if (unlikely(item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
285 					  btrfs_file_extent_ram_bytes(leaf, fi))) {
286 			file_extent_err(leaf, slot,
287 	"invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
288 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
289 				btrfs_file_extent_ram_bytes(leaf, fi));
290 			return -EUCLEAN;
291 		}
292 		return 0;
293 	}
294 
295 	/* Regular or preallocated extent has fixed item size */
296 	if (unlikely(item_size != sizeof(*fi))) {
297 		file_extent_err(leaf, slot,
298 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
299 			item_size, sizeof(*fi));
300 		return -EUCLEAN;
301 	}
302 	if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
303 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
304 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
305 		     CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
306 		     CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize)))
307 		return -EUCLEAN;
308 
309 	/* Catch extent end overflow */
310 	if (unlikely(check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
311 					key->offset, &extent_end))) {
312 		file_extent_err(leaf, slot,
313 	"extent end overflow, have file offset %llu extent num bytes %llu",
314 				key->offset,
315 				btrfs_file_extent_num_bytes(leaf, fi));
316 		return -EUCLEAN;
317 	}
318 
319 	/*
320 	 * Check that no two consecutive file extent items, in the same leaf,
321 	 * present ranges that overlap each other.
322 	 */
323 	if (slot > 0 &&
324 	    prev_key->objectid == key->objectid &&
325 	    prev_key->type == BTRFS_EXTENT_DATA_KEY) {
326 		struct btrfs_file_extent_item *prev_fi;
327 		u64 prev_end;
328 
329 		prev_fi = btrfs_item_ptr(leaf, slot - 1,
330 					 struct btrfs_file_extent_item);
331 		prev_end = file_extent_end(leaf, prev_key, prev_fi);
332 		if (unlikely(prev_end > key->offset)) {
333 			file_extent_err(leaf, slot - 1,
334 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
335 					prev_end, key->offset);
336 			return -EUCLEAN;
337 		}
338 	}
339 
340 	return 0;
341 }
342 
check_csum_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)343 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
344 			   int slot, struct btrfs_key *prev_key)
345 {
346 	struct btrfs_fs_info *fs_info = leaf->fs_info;
347 	u32 sectorsize = fs_info->sectorsize;
348 	const u32 csumsize = fs_info->csum_size;
349 
350 	if (unlikely(key->objectid != BTRFS_EXTENT_CSUM_OBJECTID)) {
351 		generic_err(leaf, slot,
352 		"invalid key objectid for csum item, have %llu expect %llu",
353 			key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
354 		return -EUCLEAN;
355 	}
356 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
357 		generic_err(leaf, slot,
358 	"unaligned key offset for csum item, have %llu should be aligned to %u",
359 			key->offset, sectorsize);
360 		return -EUCLEAN;
361 	}
362 	if (unlikely(!IS_ALIGNED(btrfs_item_size(leaf, slot), csumsize))) {
363 		generic_err(leaf, slot,
364 	"unaligned item size for csum item, have %u should be aligned to %u",
365 			btrfs_item_size(leaf, slot), csumsize);
366 		return -EUCLEAN;
367 	}
368 	if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
369 		u64 prev_csum_end;
370 		u32 prev_item_size;
371 
372 		prev_item_size = btrfs_item_size(leaf, slot - 1);
373 		prev_csum_end = (prev_item_size / csumsize) * sectorsize;
374 		prev_csum_end += prev_key->offset;
375 		if (unlikely(prev_csum_end > key->offset)) {
376 			generic_err(leaf, slot - 1,
377 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
378 				    prev_csum_end, key->offset);
379 			return -EUCLEAN;
380 		}
381 	}
382 	return 0;
383 }
384 
385 /* Inode item error output has the same format as dir_item_err() */
386 #define inode_item_err(eb, slot, fmt, ...)			\
387 	dir_item_err(eb, slot, fmt, __VA_ARGS__)
388 
check_inode_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)389 static int check_inode_key(struct extent_buffer *leaf, struct btrfs_key *key,
390 			   int slot)
391 {
392 	struct btrfs_key item_key;
393 	bool is_inode_item;
394 
395 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
396 	is_inode_item = (item_key.type == BTRFS_INODE_ITEM_KEY);
397 
398 	/* For XATTR_ITEM, location key should be all 0 */
399 	if (item_key.type == BTRFS_XATTR_ITEM_KEY) {
400 		if (unlikely(key->objectid != 0 || key->type != 0 ||
401 			     key->offset != 0))
402 			return -EUCLEAN;
403 		return 0;
404 	}
405 
406 	if (unlikely((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
407 		      key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
408 		     key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
409 		     key->objectid != BTRFS_FREE_INO_OBJECTID)) {
410 		if (is_inode_item) {
411 			generic_err(leaf, slot,
412 	"invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
413 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
414 				BTRFS_FIRST_FREE_OBJECTID,
415 				BTRFS_LAST_FREE_OBJECTID,
416 				BTRFS_FREE_INO_OBJECTID);
417 		} else {
418 			dir_item_err(leaf, slot,
419 "invalid location key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
420 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
421 				BTRFS_FIRST_FREE_OBJECTID,
422 				BTRFS_LAST_FREE_OBJECTID,
423 				BTRFS_FREE_INO_OBJECTID);
424 		}
425 		return -EUCLEAN;
426 	}
427 	if (unlikely(key->offset != 0)) {
428 		if (is_inode_item)
429 			inode_item_err(leaf, slot,
430 				       "invalid key offset: has %llu expect 0",
431 				       key->offset);
432 		else
433 			dir_item_err(leaf, slot,
434 				"invalid location key offset:has %llu expect 0",
435 				key->offset);
436 		return -EUCLEAN;
437 	}
438 	return 0;
439 }
440 
check_root_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)441 static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
442 			  int slot)
443 {
444 	struct btrfs_key item_key;
445 	bool is_root_item;
446 
447 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
448 	is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
449 
450 	/*
451 	 * Bad rootid for reloc trees.
452 	 *
453 	 * Reloc trees are only for subvolume trees, other trees only need
454 	 * to be COWed to be relocated.
455 	 */
456 	if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
457 		     !is_fstree(key->offset))) {
458 		generic_err(leaf, slot,
459 		"invalid reloc tree for root %lld, root id is not a subvolume tree",
460 			    key->offset);
461 		return -EUCLEAN;
462 	}
463 
464 	/* No such tree id */
465 	if (unlikely(key->objectid == 0)) {
466 		if (is_root_item)
467 			generic_err(leaf, slot, "invalid root id 0");
468 		else
469 			dir_item_err(leaf, slot,
470 				     "invalid location key root id 0");
471 		return -EUCLEAN;
472 	}
473 
474 	/* DIR_ITEM/INDEX/INODE_REF is not allowed to point to non-fs trees */
475 	if (unlikely(!is_fstree(key->objectid) && !is_root_item)) {
476 		dir_item_err(leaf, slot,
477 		"invalid location key objectid, have %llu expect [%llu, %llu]",
478 				key->objectid, BTRFS_FIRST_FREE_OBJECTID,
479 				BTRFS_LAST_FREE_OBJECTID);
480 		return -EUCLEAN;
481 	}
482 
483 	/*
484 	 * ROOT_ITEM with non-zero offset means this is a snapshot, created at
485 	 * @offset transid.
486 	 * Furthermore, for location key in DIR_ITEM, its offset is always -1.
487 	 *
488 	 * So here we only check offset for reloc tree whose key->offset must
489 	 * be a valid tree.
490 	 */
491 	if (unlikely(key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
492 		     key->offset == 0)) {
493 		generic_err(leaf, slot, "invalid root id 0 for reloc tree");
494 		return -EUCLEAN;
495 	}
496 	return 0;
497 }
498 
check_dir_item(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_key * prev_key,int slot)499 static int check_dir_item(struct extent_buffer *leaf,
500 			  struct btrfs_key *key, struct btrfs_key *prev_key,
501 			  int slot)
502 {
503 	struct btrfs_fs_info *fs_info = leaf->fs_info;
504 	struct btrfs_dir_item *di;
505 	u32 item_size = btrfs_item_size(leaf, slot);
506 	u32 cur = 0;
507 
508 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
509 		return -EUCLEAN;
510 
511 	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
512 	while (cur < item_size) {
513 		struct btrfs_key location_key;
514 		u32 name_len;
515 		u32 data_len;
516 		u32 max_name_len;
517 		u32 total_size;
518 		u32 name_hash;
519 		u8 dir_type;
520 		int ret;
521 
522 		/* header itself should not cross item boundary */
523 		if (unlikely(cur + sizeof(*di) > item_size)) {
524 			dir_item_err(leaf, slot,
525 		"dir item header crosses item boundary, have %zu boundary %u",
526 				cur + sizeof(*di), item_size);
527 			return -EUCLEAN;
528 		}
529 
530 		/* Location key check */
531 		btrfs_dir_item_key_to_cpu(leaf, di, &location_key);
532 		if (location_key.type == BTRFS_ROOT_ITEM_KEY) {
533 			ret = check_root_key(leaf, &location_key, slot);
534 			if (unlikely(ret < 0))
535 				return ret;
536 		} else if (location_key.type == BTRFS_INODE_ITEM_KEY ||
537 			   location_key.type == 0) {
538 			ret = check_inode_key(leaf, &location_key, slot);
539 			if (unlikely(ret < 0))
540 				return ret;
541 		} else {
542 			dir_item_err(leaf, slot,
543 			"invalid location key type, have %u, expect %u or %u",
544 				     location_key.type, BTRFS_ROOT_ITEM_KEY,
545 				     BTRFS_INODE_ITEM_KEY);
546 			return -EUCLEAN;
547 		}
548 
549 		/* dir type check */
550 		dir_type = btrfs_dir_ftype(leaf, di);
551 		if (unlikely(dir_type <= BTRFS_FT_UNKNOWN ||
552 			     dir_type >= BTRFS_FT_MAX)) {
553 			dir_item_err(leaf, slot,
554 			"invalid dir item type, have %u expect (0, %u)",
555 				dir_type, BTRFS_FT_MAX);
556 			return -EUCLEAN;
557 		}
558 
559 		if (unlikely(key->type == BTRFS_XATTR_ITEM_KEY &&
560 			     dir_type != BTRFS_FT_XATTR)) {
561 			dir_item_err(leaf, slot,
562 		"invalid dir item type for XATTR key, have %u expect %u",
563 				dir_type, BTRFS_FT_XATTR);
564 			return -EUCLEAN;
565 		}
566 		if (unlikely(dir_type == BTRFS_FT_XATTR &&
567 			     key->type != BTRFS_XATTR_ITEM_KEY)) {
568 			dir_item_err(leaf, slot,
569 			"xattr dir type found for non-XATTR key");
570 			return -EUCLEAN;
571 		}
572 		if (dir_type == BTRFS_FT_XATTR)
573 			max_name_len = XATTR_NAME_MAX;
574 		else
575 			max_name_len = BTRFS_NAME_LEN;
576 
577 		/* Name/data length check */
578 		name_len = btrfs_dir_name_len(leaf, di);
579 		data_len = btrfs_dir_data_len(leaf, di);
580 		if (unlikely(name_len > max_name_len)) {
581 			dir_item_err(leaf, slot,
582 			"dir item name len too long, have %u max %u",
583 				name_len, max_name_len);
584 			return -EUCLEAN;
585 		}
586 		if (unlikely(name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info))) {
587 			dir_item_err(leaf, slot,
588 			"dir item name and data len too long, have %u max %u",
589 				name_len + data_len,
590 				BTRFS_MAX_XATTR_SIZE(fs_info));
591 			return -EUCLEAN;
592 		}
593 
594 		if (unlikely(data_len && dir_type != BTRFS_FT_XATTR)) {
595 			dir_item_err(leaf, slot,
596 			"dir item with invalid data len, have %u expect 0",
597 				data_len);
598 			return -EUCLEAN;
599 		}
600 
601 		total_size = sizeof(*di) + name_len + data_len;
602 
603 		/* header and name/data should not cross item boundary */
604 		if (unlikely(cur + total_size > item_size)) {
605 			dir_item_err(leaf, slot,
606 		"dir item data crosses item boundary, have %u boundary %u",
607 				cur + total_size, item_size);
608 			return -EUCLEAN;
609 		}
610 
611 		/*
612 		 * Special check for XATTR/DIR_ITEM, as key->offset is name
613 		 * hash, should match its name
614 		 */
615 		if (key->type == BTRFS_DIR_ITEM_KEY ||
616 		    key->type == BTRFS_XATTR_ITEM_KEY) {
617 			char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
618 
619 			read_extent_buffer(leaf, namebuf,
620 					(unsigned long)(di + 1), name_len);
621 			name_hash = btrfs_name_hash(namebuf, name_len);
622 			if (unlikely(key->offset != name_hash)) {
623 				dir_item_err(leaf, slot,
624 		"name hash mismatch with key, have 0x%016x expect 0x%016llx",
625 					name_hash, key->offset);
626 				return -EUCLEAN;
627 			}
628 		}
629 		cur += total_size;
630 		di = (struct btrfs_dir_item *)((void *)di + total_size);
631 	}
632 	return 0;
633 }
634 
635 __printf(3, 4)
636 __cold
block_group_err(const struct extent_buffer * eb,int slot,const char * fmt,...)637 static void block_group_err(const struct extent_buffer *eb, int slot,
638 			    const char *fmt, ...)
639 {
640 	const struct btrfs_fs_info *fs_info = eb->fs_info;
641 	struct btrfs_key key;
642 	struct va_format vaf;
643 	va_list args;
644 
645 	btrfs_item_key_to_cpu(eb, &key, slot);
646 	va_start(args, fmt);
647 
648 	vaf.fmt = fmt;
649 	vaf.va = &args;
650 
651 	btrfs_crit(fs_info,
652 	"corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
653 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
654 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
655 		key.objectid, key.offset, &vaf);
656 	va_end(args);
657 }
658 
check_block_group_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)659 static int check_block_group_item(struct extent_buffer *leaf,
660 				  struct btrfs_key *key, int slot)
661 {
662 	struct btrfs_fs_info *fs_info = leaf->fs_info;
663 	struct btrfs_block_group_item bgi;
664 	u32 item_size = btrfs_item_size(leaf, slot);
665 	u64 chunk_objectid;
666 	u64 flags;
667 	u64 type;
668 
669 	/*
670 	 * Here we don't really care about alignment since extent allocator can
671 	 * handle it.  We care more about the size.
672 	 */
673 	if (unlikely(key->offset == 0)) {
674 		block_group_err(leaf, slot,
675 				"invalid block group size 0");
676 		return -EUCLEAN;
677 	}
678 
679 	if (unlikely(item_size != sizeof(bgi))) {
680 		block_group_err(leaf, slot,
681 			"invalid item size, have %u expect %zu",
682 				item_size, sizeof(bgi));
683 		return -EUCLEAN;
684 	}
685 
686 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
687 			   sizeof(bgi));
688 	chunk_objectid = btrfs_stack_block_group_chunk_objectid(&bgi);
689 	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
690 		/*
691 		 * We don't init the nr_global_roots until we load the global
692 		 * roots, so this could be 0 at mount time.  If it's 0 we'll
693 		 * just assume we're fine, and later we'll check against our
694 		 * actual value.
695 		 */
696 		if (unlikely(fs_info->nr_global_roots &&
697 			     chunk_objectid >= fs_info->nr_global_roots)) {
698 			block_group_err(leaf, slot,
699 	"invalid block group global root id, have %llu, needs to be <= %llu",
700 					chunk_objectid,
701 					fs_info->nr_global_roots);
702 			return -EUCLEAN;
703 		}
704 	} else if (unlikely(chunk_objectid != BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
705 		block_group_err(leaf, slot,
706 		"invalid block group chunk objectid, have %llu expect %llu",
707 				btrfs_stack_block_group_chunk_objectid(&bgi),
708 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
709 		return -EUCLEAN;
710 	}
711 
712 	if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
713 		block_group_err(leaf, slot,
714 			"invalid block group used, have %llu expect [0, %llu)",
715 				btrfs_stack_block_group_used(&bgi), key->offset);
716 		return -EUCLEAN;
717 	}
718 
719 	flags = btrfs_stack_block_group_flags(&bgi);
720 	if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
721 		block_group_err(leaf, slot,
722 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
723 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
724 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
725 		return -EUCLEAN;
726 	}
727 
728 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
729 	if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
730 		     type != BTRFS_BLOCK_GROUP_METADATA &&
731 		     type != BTRFS_BLOCK_GROUP_SYSTEM &&
732 		     type != (BTRFS_BLOCK_GROUP_METADATA |
733 			      BTRFS_BLOCK_GROUP_DATA))) {
734 		block_group_err(leaf, slot,
735 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
736 			type, hweight64(type),
737 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
738 			BTRFS_BLOCK_GROUP_SYSTEM,
739 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
740 		return -EUCLEAN;
741 	}
742 	return 0;
743 }
744 
745 __printf(4, 5)
746 __cold
chunk_err(const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,const char * fmt,...)747 static void chunk_err(const struct extent_buffer *leaf,
748 		      const struct btrfs_chunk *chunk, u64 logical,
749 		      const char *fmt, ...)
750 {
751 	const struct btrfs_fs_info *fs_info = leaf->fs_info;
752 	bool is_sb;
753 	struct va_format vaf;
754 	va_list args;
755 	int i;
756 	int slot = -1;
757 
758 	/* Only superblock eb is able to have such small offset */
759 	is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
760 
761 	if (!is_sb) {
762 		/*
763 		 * Get the slot number by iterating through all slots, this
764 		 * would provide better readability.
765 		 */
766 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
767 			if (btrfs_item_ptr_offset(leaf, i) ==
768 					(unsigned long)chunk) {
769 				slot = i;
770 				break;
771 			}
772 		}
773 	}
774 	va_start(args, fmt);
775 	vaf.fmt = fmt;
776 	vaf.va = &args;
777 
778 	if (is_sb)
779 		btrfs_crit(fs_info,
780 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
781 			   logical, &vaf);
782 	else
783 		btrfs_crit(fs_info,
784 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
785 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
786 			   logical, &vaf);
787 	va_end(args);
788 }
789 
790 /*
791  * The common chunk check which could also work on super block sys chunk array.
792  *
793  * Return -EUCLEAN if anything is corrupted.
794  * Return 0 if everything is OK.
795  */
btrfs_check_chunk_valid(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 logical)796 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
797 			    struct btrfs_chunk *chunk, u64 logical)
798 {
799 	struct btrfs_fs_info *fs_info = leaf->fs_info;
800 	u64 length;
801 	u64 chunk_end;
802 	u64 stripe_len;
803 	u16 num_stripes;
804 	u16 sub_stripes;
805 	u64 type;
806 	u64 features;
807 	bool mixed = false;
808 	int raid_index;
809 	int nparity;
810 	int ncopies;
811 
812 	length = btrfs_chunk_length(leaf, chunk);
813 	stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
814 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
815 	sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
816 	type = btrfs_chunk_type(leaf, chunk);
817 	raid_index = btrfs_bg_flags_to_raid_index(type);
818 	ncopies = btrfs_raid_array[raid_index].ncopies;
819 	nparity = btrfs_raid_array[raid_index].nparity;
820 
821 	if (unlikely(!num_stripes)) {
822 		chunk_err(leaf, chunk, logical,
823 			  "invalid chunk num_stripes, have %u", num_stripes);
824 		return -EUCLEAN;
825 	}
826 	if (unlikely(num_stripes < ncopies)) {
827 		chunk_err(leaf, chunk, logical,
828 			  "invalid chunk num_stripes < ncopies, have %u < %d",
829 			  num_stripes, ncopies);
830 		return -EUCLEAN;
831 	}
832 	if (unlikely(nparity && num_stripes == nparity)) {
833 		chunk_err(leaf, chunk, logical,
834 			  "invalid chunk num_stripes == nparity, have %u == %d",
835 			  num_stripes, nparity);
836 		return -EUCLEAN;
837 	}
838 	if (unlikely(!IS_ALIGNED(logical, fs_info->sectorsize))) {
839 		chunk_err(leaf, chunk, logical,
840 		"invalid chunk logical, have %llu should aligned to %u",
841 			  logical, fs_info->sectorsize);
842 		return -EUCLEAN;
843 	}
844 	if (unlikely(btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize)) {
845 		chunk_err(leaf, chunk, logical,
846 			  "invalid chunk sectorsize, have %u expect %u",
847 			  btrfs_chunk_sector_size(leaf, chunk),
848 			  fs_info->sectorsize);
849 		return -EUCLEAN;
850 	}
851 	if (unlikely(!length || !IS_ALIGNED(length, fs_info->sectorsize))) {
852 		chunk_err(leaf, chunk, logical,
853 			  "invalid chunk length, have %llu", length);
854 		return -EUCLEAN;
855 	}
856 	if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
857 		chunk_err(leaf, chunk, logical,
858 "invalid chunk logical start and length, have logical start %llu length %llu",
859 			  logical, length);
860 		return -EUCLEAN;
861 	}
862 	if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
863 		chunk_err(leaf, chunk, logical,
864 			  "invalid chunk stripe length: %llu",
865 			  stripe_len);
866 		return -EUCLEAN;
867 	}
868 	/*
869 	 * We artificially limit the chunk size, so that the number of stripes
870 	 * inside a chunk can be fit into a U32.  The current limit (256G) is
871 	 * way too large for real world usage anyway, and it's also much larger
872 	 * than our existing limit (10G).
873 	 *
874 	 * Thus it should be a good way to catch obvious bitflips.
875 	 */
876 	if (unlikely(length >= btrfs_stripe_nr_to_offset(U32_MAX))) {
877 		chunk_err(leaf, chunk, logical,
878 			  "chunk length too large: have %llu limit %llu",
879 			  length, btrfs_stripe_nr_to_offset(U32_MAX));
880 		return -EUCLEAN;
881 	}
882 	if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
883 			      BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
884 		chunk_err(leaf, chunk, logical,
885 			  "unrecognized chunk type: 0x%llx",
886 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
887 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) &
888 			  btrfs_chunk_type(leaf, chunk));
889 		return -EUCLEAN;
890 	}
891 
892 	if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
893 		     (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
894 		chunk_err(leaf, chunk, logical,
895 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
896 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
897 		return -EUCLEAN;
898 	}
899 	if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
900 		chunk_err(leaf, chunk, logical,
901 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
902 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
903 		return -EUCLEAN;
904 	}
905 
906 	if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
907 		     (type & (BTRFS_BLOCK_GROUP_METADATA |
908 			      BTRFS_BLOCK_GROUP_DATA)))) {
909 		chunk_err(leaf, chunk, logical,
910 			  "system chunk with data or metadata type: 0x%llx",
911 			  type);
912 		return -EUCLEAN;
913 	}
914 
915 	features = btrfs_super_incompat_flags(fs_info->super_copy);
916 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
917 		mixed = true;
918 
919 	if (!mixed) {
920 		if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
921 			     (type & BTRFS_BLOCK_GROUP_DATA))) {
922 			chunk_err(leaf, chunk, logical,
923 			"mixed chunk type in non-mixed mode: 0x%llx", type);
924 			return -EUCLEAN;
925 		}
926 	}
927 
928 	if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
929 		      sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
930 		     (type & BTRFS_BLOCK_GROUP_RAID1 &&
931 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
932 		     (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
933 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
934 		     (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
935 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
936 		     (type & BTRFS_BLOCK_GROUP_RAID5 &&
937 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
938 		     (type & BTRFS_BLOCK_GROUP_RAID6 &&
939 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
940 		     (type & BTRFS_BLOCK_GROUP_DUP &&
941 		      num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
942 		     ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
943 		      num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
944 		chunk_err(leaf, chunk, logical,
945 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
946 			num_stripes, sub_stripes,
947 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
948 		return -EUCLEAN;
949 	}
950 
951 	return 0;
952 }
953 
954 /*
955  * Enhanced version of chunk item checker.
956  *
957  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
958  * to work on super block sys_chunk_array which doesn't have full item ptr.
959  */
check_leaf_chunk_item(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_key * key,int slot)960 static int check_leaf_chunk_item(struct extent_buffer *leaf,
961 				 struct btrfs_chunk *chunk,
962 				 struct btrfs_key *key, int slot)
963 {
964 	int num_stripes;
965 
966 	if (unlikely(btrfs_item_size(leaf, slot) < sizeof(struct btrfs_chunk))) {
967 		chunk_err(leaf, chunk, key->offset,
968 			"invalid chunk item size: have %u expect [%zu, %u)",
969 			btrfs_item_size(leaf, slot),
970 			sizeof(struct btrfs_chunk),
971 			BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
972 		return -EUCLEAN;
973 	}
974 
975 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
976 	/* Let btrfs_check_chunk_valid() handle this error type */
977 	if (num_stripes == 0)
978 		goto out;
979 
980 	if (unlikely(btrfs_chunk_item_size(num_stripes) !=
981 		     btrfs_item_size(leaf, slot))) {
982 		chunk_err(leaf, chunk, key->offset,
983 			"invalid chunk item size: have %u expect %lu",
984 			btrfs_item_size(leaf, slot),
985 			btrfs_chunk_item_size(num_stripes));
986 		return -EUCLEAN;
987 	}
988 out:
989 	return btrfs_check_chunk_valid(leaf, chunk, key->offset);
990 }
991 
992 __printf(3, 4)
993 __cold
dev_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)994 static void dev_item_err(const struct extent_buffer *eb, int slot,
995 			 const char *fmt, ...)
996 {
997 	struct btrfs_key key;
998 	struct va_format vaf;
999 	va_list args;
1000 
1001 	btrfs_item_key_to_cpu(eb, &key, slot);
1002 	va_start(args, fmt);
1003 
1004 	vaf.fmt = fmt;
1005 	vaf.va = &args;
1006 
1007 	btrfs_crit(eb->fs_info,
1008 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
1009 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1010 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
1011 		key.objectid, &vaf);
1012 	va_end(args);
1013 }
1014 
check_dev_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1015 static int check_dev_item(struct extent_buffer *leaf,
1016 			  struct btrfs_key *key, int slot)
1017 {
1018 	struct btrfs_dev_item *ditem;
1019 	const u32 item_size = btrfs_item_size(leaf, slot);
1020 
1021 	if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
1022 		dev_item_err(leaf, slot,
1023 			     "invalid objectid: has=%llu expect=%llu",
1024 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
1025 		return -EUCLEAN;
1026 	}
1027 
1028 	if (unlikely(item_size != sizeof(*ditem))) {
1029 		dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
1030 			     item_size, sizeof(*ditem));
1031 		return -EUCLEAN;
1032 	}
1033 
1034 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
1035 	if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
1036 		dev_item_err(leaf, slot,
1037 			     "devid mismatch: key has=%llu item has=%llu",
1038 			     key->offset, btrfs_device_id(leaf, ditem));
1039 		return -EUCLEAN;
1040 	}
1041 
1042 	/*
1043 	 * For device total_bytes, we don't have reliable way to check it, as
1044 	 * it can be 0 for device removal. Device size check can only be done
1045 	 * by dev extents check.
1046 	 */
1047 	if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1048 		     btrfs_device_total_bytes(leaf, ditem))) {
1049 		dev_item_err(leaf, slot,
1050 			     "invalid bytes used: have %llu expect [0, %llu]",
1051 			     btrfs_device_bytes_used(leaf, ditem),
1052 			     btrfs_device_total_bytes(leaf, ditem));
1053 		return -EUCLEAN;
1054 	}
1055 	/*
1056 	 * Remaining members like io_align/type/gen/dev_group aren't really
1057 	 * utilized.  Skip them to make later usage of them easier.
1058 	 */
1059 	return 0;
1060 }
1061 
check_inode_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1062 static int check_inode_item(struct extent_buffer *leaf,
1063 			    struct btrfs_key *key, int slot)
1064 {
1065 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1066 	struct btrfs_inode_item *iitem;
1067 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1068 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1069 	const u32 item_size = btrfs_item_size(leaf, slot);
1070 	u32 mode;
1071 	int ret;
1072 	u32 flags;
1073 	u32 ro_flags;
1074 
1075 	ret = check_inode_key(leaf, key, slot);
1076 	if (unlikely(ret < 0))
1077 		return ret;
1078 
1079 	if (unlikely(item_size != sizeof(*iitem))) {
1080 		generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1081 			    item_size, sizeof(*iitem));
1082 		return -EUCLEAN;
1083 	}
1084 
1085 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1086 
1087 	/* Here we use super block generation + 1 to handle log tree */
1088 	if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1089 		inode_item_err(leaf, slot,
1090 			"invalid inode generation: has %llu expect (0, %llu]",
1091 			       btrfs_inode_generation(leaf, iitem),
1092 			       super_gen + 1);
1093 		return -EUCLEAN;
1094 	}
1095 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1096 	if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1097 		inode_item_err(leaf, slot,
1098 			"invalid inode transid: has %llu expect [0, %llu]",
1099 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
1100 		return -EUCLEAN;
1101 	}
1102 
1103 	/*
1104 	 * For size and nbytes it's better not to be too strict, as for dir
1105 	 * item its size/nbytes can easily get wrong, but doesn't affect
1106 	 * anything in the fs. So here we skip the check.
1107 	 */
1108 	mode = btrfs_inode_mode(leaf, iitem);
1109 	if (unlikely(mode & ~valid_mask)) {
1110 		inode_item_err(leaf, slot,
1111 			       "unknown mode bit detected: 0x%x",
1112 			       mode & ~valid_mask);
1113 		return -EUCLEAN;
1114 	}
1115 
1116 	/*
1117 	 * S_IFMT is not bit mapped so we can't completely rely on
1118 	 * is_power_of_2/has_single_bit_set, but it can save us from checking
1119 	 * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1120 	 */
1121 	if (!has_single_bit_set(mode & S_IFMT)) {
1122 		if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1123 			inode_item_err(leaf, slot,
1124 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
1125 				       mode & S_IFMT);
1126 			return -EUCLEAN;
1127 		}
1128 	}
1129 	if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1130 		inode_item_err(leaf, slot,
1131 		       "invalid nlink: has %u expect no more than 1 for dir",
1132 			btrfs_inode_nlink(leaf, iitem));
1133 		return -EUCLEAN;
1134 	}
1135 	btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1136 	if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1137 		inode_item_err(leaf, slot,
1138 			       "unknown incompat flags detected: 0x%x", flags);
1139 		return -EUCLEAN;
1140 	}
1141 	if (unlikely(!sb_rdonly(fs_info->sb) &&
1142 		     (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1143 		inode_item_err(leaf, slot,
1144 			"unknown ro-compat flags detected on writeable mount: 0x%x",
1145 			ro_flags);
1146 		return -EUCLEAN;
1147 	}
1148 	return 0;
1149 }
1150 
check_root_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1151 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1152 			   int slot)
1153 {
1154 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1155 	struct btrfs_root_item ri = { 0 };
1156 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1157 				     BTRFS_ROOT_SUBVOL_DEAD;
1158 	int ret;
1159 
1160 	ret = check_root_key(leaf, key, slot);
1161 	if (unlikely(ret < 0))
1162 		return ret;
1163 
1164 	if (unlikely(btrfs_item_size(leaf, slot) != sizeof(ri) &&
1165 		     btrfs_item_size(leaf, slot) !=
1166 		     btrfs_legacy_root_item_size())) {
1167 		generic_err(leaf, slot,
1168 			    "invalid root item size, have %u expect %zu or %u",
1169 			    btrfs_item_size(leaf, slot), sizeof(ri),
1170 			    btrfs_legacy_root_item_size());
1171 		return -EUCLEAN;
1172 	}
1173 
1174 	/*
1175 	 * For legacy root item, the members starting at generation_v2 will be
1176 	 * all filled with 0.
1177 	 * And since we allow geneartion_v2 as 0, it will still pass the check.
1178 	 */
1179 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1180 			   btrfs_item_size(leaf, slot));
1181 
1182 	/* Generation related */
1183 	if (unlikely(btrfs_root_generation(&ri) >
1184 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1185 		generic_err(leaf, slot,
1186 			"invalid root generation, have %llu expect (0, %llu]",
1187 			    btrfs_root_generation(&ri),
1188 			    btrfs_super_generation(fs_info->super_copy) + 1);
1189 		return -EUCLEAN;
1190 	}
1191 	if (unlikely(btrfs_root_generation_v2(&ri) >
1192 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1193 		generic_err(leaf, slot,
1194 		"invalid root v2 generation, have %llu expect (0, %llu]",
1195 			    btrfs_root_generation_v2(&ri),
1196 			    btrfs_super_generation(fs_info->super_copy) + 1);
1197 		return -EUCLEAN;
1198 	}
1199 	if (unlikely(btrfs_root_last_snapshot(&ri) >
1200 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1201 		generic_err(leaf, slot,
1202 		"invalid root last_snapshot, have %llu expect (0, %llu]",
1203 			    btrfs_root_last_snapshot(&ri),
1204 			    btrfs_super_generation(fs_info->super_copy) + 1);
1205 		return -EUCLEAN;
1206 	}
1207 
1208 	/* Alignment and level check */
1209 	if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1210 		generic_err(leaf, slot,
1211 		"invalid root bytenr, have %llu expect to be aligned to %u",
1212 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
1213 		return -EUCLEAN;
1214 	}
1215 	if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1216 		generic_err(leaf, slot,
1217 			    "invalid root level, have %u expect [0, %u]",
1218 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1219 		return -EUCLEAN;
1220 	}
1221 	if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1222 		generic_err(leaf, slot,
1223 			    "invalid root level, have %u expect [0, %u]",
1224 			    btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1225 		return -EUCLEAN;
1226 	}
1227 
1228 	/* Flags check */
1229 	if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1230 		generic_err(leaf, slot,
1231 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
1232 			    btrfs_root_flags(&ri), valid_root_flags);
1233 		return -EUCLEAN;
1234 	}
1235 	return 0;
1236 }
1237 
1238 __printf(3,4)
1239 __cold
extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)1240 static void extent_err(const struct extent_buffer *eb, int slot,
1241 		       const char *fmt, ...)
1242 {
1243 	struct btrfs_key key;
1244 	struct va_format vaf;
1245 	va_list args;
1246 	u64 bytenr;
1247 	u64 len;
1248 
1249 	btrfs_item_key_to_cpu(eb, &key, slot);
1250 	bytenr = key.objectid;
1251 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
1252 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1253 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1254 		len = eb->fs_info->nodesize;
1255 	else
1256 		len = key.offset;
1257 	va_start(args, fmt);
1258 
1259 	vaf.fmt = fmt;
1260 	vaf.va = &args;
1261 
1262 	btrfs_crit(eb->fs_info,
1263 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1264 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1265 		eb->start, slot, bytenr, len, &vaf);
1266 	va_end(args);
1267 }
1268 
check_extent_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1269 static int check_extent_item(struct extent_buffer *leaf,
1270 			     struct btrfs_key *key, int slot,
1271 			     struct btrfs_key *prev_key)
1272 {
1273 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1274 	struct btrfs_extent_item *ei;
1275 	bool is_tree_block = false;
1276 	unsigned long ptr;	/* Current pointer inside inline refs */
1277 	unsigned long end;	/* Extent item end */
1278 	const u32 item_size = btrfs_item_size(leaf, slot);
1279 	u8 last_type = 0;
1280 	u64 last_seq = U64_MAX;
1281 	u64 flags;
1282 	u64 generation;
1283 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1284 	u64 inline_refs = 0;	/* found total inline refs */
1285 
1286 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1287 		     !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1288 		generic_err(leaf, slot,
1289 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1290 		return -EUCLEAN;
1291 	}
1292 	/* key->objectid is the bytenr for both key types */
1293 	if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1294 		generic_err(leaf, slot,
1295 		"invalid key objectid, have %llu expect to be aligned to %u",
1296 			   key->objectid, fs_info->sectorsize);
1297 		return -EUCLEAN;
1298 	}
1299 
1300 	/* key->offset is tree level for METADATA_ITEM_KEY */
1301 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1302 		     key->offset >= BTRFS_MAX_LEVEL)) {
1303 		extent_err(leaf, slot,
1304 			   "invalid tree level, have %llu expect [0, %u]",
1305 			   key->offset, BTRFS_MAX_LEVEL - 1);
1306 		return -EUCLEAN;
1307 	}
1308 
1309 	/*
1310 	 * EXTENT/METADATA_ITEM consists of:
1311 	 * 1) One btrfs_extent_item
1312 	 *    Records the total refs, type and generation of the extent.
1313 	 *
1314 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1315 	 *    Records the first key and level of the tree block.
1316 	 *
1317 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1318 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1319 	 *    2.1) The ref type, one of the 4
1320 	 *         TREE_BLOCK_REF	Tree block only
1321 	 *         SHARED_BLOCK_REF	Tree block only
1322 	 *         EXTENT_DATA_REF	Data only
1323 	 *         SHARED_DATA_REF	Data only
1324 	 *    2.2) Ref type specific data
1325 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1326 	 *         data structure.
1327 	 *
1328 	 *    All above inline items should follow the order:
1329 	 *
1330 	 *    - All btrfs_extent_inline_ref::type should be in an ascending
1331 	 *      order
1332 	 *
1333 	 *    - Within the same type, the items should follow a descending
1334 	 *      order by their sequence number. The sequence number is
1335 	 *      determined by:
1336 	 *      * btrfs_extent_inline_ref::offset for all types  other than
1337 	 *        EXTENT_DATA_REF
1338 	 *      * hash_extent_data_ref() for EXTENT_DATA_REF
1339 	 */
1340 	if (unlikely(item_size < sizeof(*ei))) {
1341 		extent_err(leaf, slot,
1342 			   "invalid item size, have %u expect [%zu, %u)",
1343 			   item_size, sizeof(*ei),
1344 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1345 		return -EUCLEAN;
1346 	}
1347 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1348 
1349 	/* Checks against extent_item */
1350 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1351 	flags = btrfs_extent_flags(leaf, ei);
1352 	total_refs = btrfs_extent_refs(leaf, ei);
1353 	generation = btrfs_extent_generation(leaf, ei);
1354 	if (unlikely(generation >
1355 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1356 		extent_err(leaf, slot,
1357 			   "invalid generation, have %llu expect (0, %llu]",
1358 			   generation,
1359 			   btrfs_super_generation(fs_info->super_copy) + 1);
1360 		return -EUCLEAN;
1361 	}
1362 	if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1363 						  BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1364 		extent_err(leaf, slot,
1365 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1366 			flags, BTRFS_EXTENT_FLAG_DATA |
1367 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1368 		return -EUCLEAN;
1369 	}
1370 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1371 	if (is_tree_block) {
1372 		if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1373 			     key->offset != fs_info->nodesize)) {
1374 			extent_err(leaf, slot,
1375 				   "invalid extent length, have %llu expect %u",
1376 				   key->offset, fs_info->nodesize);
1377 			return -EUCLEAN;
1378 		}
1379 	} else {
1380 		if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1381 			extent_err(leaf, slot,
1382 			"invalid key type, have %u expect %u for data backref",
1383 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1384 			return -EUCLEAN;
1385 		}
1386 		if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1387 			extent_err(leaf, slot,
1388 			"invalid extent length, have %llu expect aligned to %u",
1389 				   key->offset, fs_info->sectorsize);
1390 			return -EUCLEAN;
1391 		}
1392 		if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1393 			extent_err(leaf, slot,
1394 			"invalid extent flag, data has full backref set");
1395 			return -EUCLEAN;
1396 		}
1397 	}
1398 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1399 
1400 	/* Check the special case of btrfs_tree_block_info */
1401 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1402 		struct btrfs_tree_block_info *info;
1403 
1404 		info = (struct btrfs_tree_block_info *)ptr;
1405 		if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1406 			extent_err(leaf, slot,
1407 			"invalid tree block info level, have %u expect [0, %u]",
1408 				   btrfs_tree_block_level(leaf, info),
1409 				   BTRFS_MAX_LEVEL - 1);
1410 			return -EUCLEAN;
1411 		}
1412 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1413 	}
1414 
1415 	/* Check inline refs */
1416 	while (ptr < end) {
1417 		struct btrfs_extent_inline_ref *iref;
1418 		struct btrfs_extent_data_ref *dref;
1419 		struct btrfs_shared_data_ref *sref;
1420 		u64 seq;
1421 		u64 dref_offset;
1422 		u64 inline_offset;
1423 		u8 inline_type;
1424 
1425 		if (unlikely(ptr + sizeof(*iref) > end)) {
1426 			extent_err(leaf, slot,
1427 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1428 				   ptr, sizeof(*iref), end);
1429 			return -EUCLEAN;
1430 		}
1431 		iref = (struct btrfs_extent_inline_ref *)ptr;
1432 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1433 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1434 		seq = inline_offset;
1435 		if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1436 			extent_err(leaf, slot,
1437 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1438 				   ptr, btrfs_extent_inline_ref_size(inline_type), end);
1439 			return -EUCLEAN;
1440 		}
1441 
1442 		switch (inline_type) {
1443 		/* inline_offset is subvolid of the owner, no need to check */
1444 		case BTRFS_TREE_BLOCK_REF_KEY:
1445 			inline_refs++;
1446 			break;
1447 		/* Contains parent bytenr */
1448 		case BTRFS_SHARED_BLOCK_REF_KEY:
1449 			if (unlikely(!IS_ALIGNED(inline_offset,
1450 						 fs_info->sectorsize))) {
1451 				extent_err(leaf, slot,
1452 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1453 					   inline_offset, fs_info->sectorsize);
1454 				return -EUCLEAN;
1455 			}
1456 			inline_refs++;
1457 			break;
1458 		/*
1459 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1460 		 * The only obvious corruption can happen in that offset.
1461 		 */
1462 		case BTRFS_EXTENT_DATA_REF_KEY:
1463 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1464 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1465 			seq = hash_extent_data_ref(
1466 					btrfs_extent_data_ref_root(leaf, dref),
1467 					btrfs_extent_data_ref_objectid(leaf, dref),
1468 					btrfs_extent_data_ref_offset(leaf, dref));
1469 			if (unlikely(!IS_ALIGNED(dref_offset,
1470 						 fs_info->sectorsize))) {
1471 				extent_err(leaf, slot,
1472 		"invalid data ref offset, have %llu expect aligned to %u",
1473 					   dref_offset, fs_info->sectorsize);
1474 				return -EUCLEAN;
1475 			}
1476 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1477 			break;
1478 		/* Contains parent bytenr and ref count */
1479 		case BTRFS_SHARED_DATA_REF_KEY:
1480 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1481 			if (unlikely(!IS_ALIGNED(inline_offset,
1482 						 fs_info->sectorsize))) {
1483 				extent_err(leaf, slot,
1484 		"invalid data parent bytenr, have %llu expect aligned to %u",
1485 					   inline_offset, fs_info->sectorsize);
1486 				return -EUCLEAN;
1487 			}
1488 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1489 			break;
1490 		default:
1491 			extent_err(leaf, slot, "unknown inline ref type: %u",
1492 				   inline_type);
1493 			return -EUCLEAN;
1494 		}
1495 		if (inline_type < last_type) {
1496 			extent_err(leaf, slot,
1497 				   "inline ref out-of-order: has type %u, prev type %u",
1498 				   inline_type, last_type);
1499 			return -EUCLEAN;
1500 		}
1501 		/* Type changed, allow the sequence starts from U64_MAX again. */
1502 		if (inline_type > last_type)
1503 			last_seq = U64_MAX;
1504 		if (seq > last_seq) {
1505 			extent_err(leaf, slot,
1506 "inline ref out-of-order: has type %u offset %llu seq 0x%llx, prev type %u seq 0x%llx",
1507 				   inline_type, inline_offset, seq,
1508 				   last_type, last_seq);
1509 			return -EUCLEAN;
1510 		}
1511 		last_type = inline_type;
1512 		last_seq = seq;
1513 		ptr += btrfs_extent_inline_ref_size(inline_type);
1514 	}
1515 	/* No padding is allowed */
1516 	if (unlikely(ptr != end)) {
1517 		extent_err(leaf, slot,
1518 			   "invalid extent item size, padding bytes found");
1519 		return -EUCLEAN;
1520 	}
1521 
1522 	/* Finally, check the inline refs against total refs */
1523 	if (unlikely(inline_refs > total_refs)) {
1524 		extent_err(leaf, slot,
1525 			"invalid extent refs, have %llu expect >= inline %llu",
1526 			   total_refs, inline_refs);
1527 		return -EUCLEAN;
1528 	}
1529 
1530 	if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1531 	    (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1532 		u64 prev_end = prev_key->objectid;
1533 
1534 		if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1535 			prev_end += fs_info->nodesize;
1536 		else
1537 			prev_end += prev_key->offset;
1538 
1539 		if (unlikely(prev_end > key->objectid)) {
1540 			extent_err(leaf, slot,
1541 	"previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1542 				   prev_key->objectid, prev_key->type,
1543 				   prev_key->offset, key->objectid, key->type,
1544 				   key->offset);
1545 			return -EUCLEAN;
1546 		}
1547 	}
1548 
1549 	return 0;
1550 }
1551 
check_simple_keyed_refs(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1552 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1553 				   struct btrfs_key *key, int slot)
1554 {
1555 	u32 expect_item_size = 0;
1556 
1557 	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1558 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1559 
1560 	if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
1561 		generic_err(leaf, slot,
1562 		"invalid item size, have %u expect %u for key type %u",
1563 			    btrfs_item_size(leaf, slot),
1564 			    expect_item_size, key->type);
1565 		return -EUCLEAN;
1566 	}
1567 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1568 		generic_err(leaf, slot,
1569 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1570 			    key->objectid, leaf->fs_info->sectorsize);
1571 		return -EUCLEAN;
1572 	}
1573 	if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1574 		     !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1575 		extent_err(leaf, slot,
1576 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1577 			   key->offset, leaf->fs_info->sectorsize);
1578 		return -EUCLEAN;
1579 	}
1580 	return 0;
1581 }
1582 
check_extent_data_ref(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1583 static int check_extent_data_ref(struct extent_buffer *leaf,
1584 				 struct btrfs_key *key, int slot)
1585 {
1586 	struct btrfs_extent_data_ref *dref;
1587 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1588 	const unsigned long end = ptr + btrfs_item_size(leaf, slot);
1589 
1590 	if (unlikely(btrfs_item_size(leaf, slot) % sizeof(*dref) != 0)) {
1591 		generic_err(leaf, slot,
1592 	"invalid item size, have %u expect aligned to %zu for key type %u",
1593 			    btrfs_item_size(leaf, slot),
1594 			    sizeof(*dref), key->type);
1595 		return -EUCLEAN;
1596 	}
1597 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1598 		generic_err(leaf, slot,
1599 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1600 			    key->objectid, leaf->fs_info->sectorsize);
1601 		return -EUCLEAN;
1602 	}
1603 	for (; ptr < end; ptr += sizeof(*dref)) {
1604 		u64 offset;
1605 
1606 		/*
1607 		 * We cannot check the extent_data_ref hash due to possible
1608 		 * overflow from the leaf due to hash collisions.
1609 		 */
1610 		dref = (struct btrfs_extent_data_ref *)ptr;
1611 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1612 		if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1613 			extent_err(leaf, slot,
1614 	"invalid extent data backref offset, have %llu expect aligned to %u",
1615 				   offset, leaf->fs_info->sectorsize);
1616 			return -EUCLEAN;
1617 		}
1618 	}
1619 	return 0;
1620 }
1621 
1622 #define inode_ref_err(eb, slot, fmt, args...)			\
1623 	inode_item_err(eb, slot, fmt, ##args)
check_inode_ref(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_key * prev_key,int slot)1624 static int check_inode_ref(struct extent_buffer *leaf,
1625 			   struct btrfs_key *key, struct btrfs_key *prev_key,
1626 			   int slot)
1627 {
1628 	struct btrfs_inode_ref *iref;
1629 	unsigned long ptr;
1630 	unsigned long end;
1631 
1632 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1633 		return -EUCLEAN;
1634 	/* namelen can't be 0, so item_size == sizeof() is also invalid */
1635 	if (unlikely(btrfs_item_size(leaf, slot) <= sizeof(*iref))) {
1636 		inode_ref_err(leaf, slot,
1637 			"invalid item size, have %u expect (%zu, %u)",
1638 			btrfs_item_size(leaf, slot),
1639 			sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1640 		return -EUCLEAN;
1641 	}
1642 
1643 	ptr = btrfs_item_ptr_offset(leaf, slot);
1644 	end = ptr + btrfs_item_size(leaf, slot);
1645 	while (ptr < end) {
1646 		u16 namelen;
1647 
1648 		if (unlikely(ptr + sizeof(iref) > end)) {
1649 			inode_ref_err(leaf, slot,
1650 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1651 				ptr, end, sizeof(iref));
1652 			return -EUCLEAN;
1653 		}
1654 
1655 		iref = (struct btrfs_inode_ref *)ptr;
1656 		namelen = btrfs_inode_ref_name_len(leaf, iref);
1657 		if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1658 			inode_ref_err(leaf, slot,
1659 				"inode ref overflow, ptr %lu end %lu namelen %u",
1660 				ptr, end, namelen);
1661 			return -EUCLEAN;
1662 		}
1663 
1664 		/*
1665 		 * NOTE: In theory we should record all found index numbers
1666 		 * to find any duplicated indexes, but that will be too time
1667 		 * consuming for inodes with too many hard links.
1668 		 */
1669 		ptr += sizeof(*iref) + namelen;
1670 	}
1671 	return 0;
1672 }
1673 
check_dev_extent_item(const struct extent_buffer * leaf,const struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1674 static int check_dev_extent_item(const struct extent_buffer *leaf,
1675 				 const struct btrfs_key *key,
1676 				 int slot,
1677 				 struct btrfs_key *prev_key)
1678 {
1679 	struct btrfs_dev_extent *de;
1680 	const u32 sectorsize = leaf->fs_info->sectorsize;
1681 
1682 	de = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
1683 	/* Basic fixed member checks. */
1684 	if (unlikely(btrfs_dev_extent_chunk_tree(leaf, de) !=
1685 		     BTRFS_CHUNK_TREE_OBJECTID)) {
1686 		generic_err(leaf, slot,
1687 			    "invalid dev extent chunk tree id, has %llu expect %llu",
1688 			    btrfs_dev_extent_chunk_tree(leaf, de),
1689 			    BTRFS_CHUNK_TREE_OBJECTID);
1690 		return -EUCLEAN;
1691 	}
1692 	if (unlikely(btrfs_dev_extent_chunk_objectid(leaf, de) !=
1693 		     BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
1694 		generic_err(leaf, slot,
1695 			    "invalid dev extent chunk objectid, has %llu expect %llu",
1696 			    btrfs_dev_extent_chunk_objectid(leaf, de),
1697 			    BTRFS_FIRST_CHUNK_TREE_OBJECTID);
1698 		return -EUCLEAN;
1699 	}
1700 	/* Alignment check. */
1701 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
1702 		generic_err(leaf, slot,
1703 			    "invalid dev extent key.offset, has %llu not aligned to %u",
1704 			    key->offset, sectorsize);
1705 		return -EUCLEAN;
1706 	}
1707 	if (unlikely(!IS_ALIGNED(btrfs_dev_extent_chunk_offset(leaf, de),
1708 				 sectorsize))) {
1709 		generic_err(leaf, slot,
1710 			    "invalid dev extent chunk offset, has %llu not aligned to %u",
1711 			    btrfs_dev_extent_chunk_objectid(leaf, de),
1712 			    sectorsize);
1713 		return -EUCLEAN;
1714 	}
1715 	if (unlikely(!IS_ALIGNED(btrfs_dev_extent_length(leaf, de),
1716 				 sectorsize))) {
1717 		generic_err(leaf, slot,
1718 			    "invalid dev extent length, has %llu not aligned to %u",
1719 			    btrfs_dev_extent_length(leaf, de), sectorsize);
1720 		return -EUCLEAN;
1721 	}
1722 	/* Overlap check with previous dev extent. */
1723 	if (slot && prev_key->objectid == key->objectid &&
1724 	    prev_key->type == key->type) {
1725 		struct btrfs_dev_extent *prev_de;
1726 		u64 prev_len;
1727 
1728 		prev_de = btrfs_item_ptr(leaf, slot - 1, struct btrfs_dev_extent);
1729 		prev_len = btrfs_dev_extent_length(leaf, prev_de);
1730 		if (unlikely(prev_key->offset + prev_len > key->offset)) {
1731 			generic_err(leaf, slot,
1732 		"dev extent overlap, prev offset %llu len %llu current offset %llu",
1733 				    prev_key->objectid, prev_len, key->offset);
1734 			return -EUCLEAN;
1735 		}
1736 	}
1737 	return 0;
1738 }
1739 
1740 /*
1741  * Common point to switch the item-specific validation.
1742  */
check_leaf_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1743 static enum btrfs_tree_block_status check_leaf_item(struct extent_buffer *leaf,
1744 						    struct btrfs_key *key,
1745 						    int slot,
1746 						    struct btrfs_key *prev_key)
1747 {
1748 	int ret = 0;
1749 	struct btrfs_chunk *chunk;
1750 
1751 	switch (key->type) {
1752 	case BTRFS_EXTENT_DATA_KEY:
1753 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1754 		break;
1755 	case BTRFS_EXTENT_CSUM_KEY:
1756 		ret = check_csum_item(leaf, key, slot, prev_key);
1757 		break;
1758 	case BTRFS_DIR_ITEM_KEY:
1759 	case BTRFS_DIR_INDEX_KEY:
1760 	case BTRFS_XATTR_ITEM_KEY:
1761 		ret = check_dir_item(leaf, key, prev_key, slot);
1762 		break;
1763 	case BTRFS_INODE_REF_KEY:
1764 		ret = check_inode_ref(leaf, key, prev_key, slot);
1765 		break;
1766 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1767 		ret = check_block_group_item(leaf, key, slot);
1768 		break;
1769 	case BTRFS_CHUNK_ITEM_KEY:
1770 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1771 		ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1772 		break;
1773 	case BTRFS_DEV_ITEM_KEY:
1774 		ret = check_dev_item(leaf, key, slot);
1775 		break;
1776 	case BTRFS_DEV_EXTENT_KEY:
1777 		ret = check_dev_extent_item(leaf, key, slot, prev_key);
1778 		break;
1779 	case BTRFS_INODE_ITEM_KEY:
1780 		ret = check_inode_item(leaf, key, slot);
1781 		break;
1782 	case BTRFS_ROOT_ITEM_KEY:
1783 		ret = check_root_item(leaf, key, slot);
1784 		break;
1785 	case BTRFS_EXTENT_ITEM_KEY:
1786 	case BTRFS_METADATA_ITEM_KEY:
1787 		ret = check_extent_item(leaf, key, slot, prev_key);
1788 		break;
1789 	case BTRFS_TREE_BLOCK_REF_KEY:
1790 	case BTRFS_SHARED_DATA_REF_KEY:
1791 	case BTRFS_SHARED_BLOCK_REF_KEY:
1792 		ret = check_simple_keyed_refs(leaf, key, slot);
1793 		break;
1794 	case BTRFS_EXTENT_DATA_REF_KEY:
1795 		ret = check_extent_data_ref(leaf, key, slot);
1796 		break;
1797 	}
1798 
1799 	if (ret)
1800 		return BTRFS_TREE_BLOCK_INVALID_ITEM;
1801 	return BTRFS_TREE_BLOCK_CLEAN;
1802 }
1803 
__btrfs_check_leaf(struct extent_buffer * leaf)1804 enum btrfs_tree_block_status __btrfs_check_leaf(struct extent_buffer *leaf)
1805 {
1806 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1807 	/* No valid key type is 0, so all key should be larger than this key */
1808 	struct btrfs_key prev_key = {0, 0, 0};
1809 	struct btrfs_key key;
1810 	u32 nritems = btrfs_header_nritems(leaf);
1811 	int slot;
1812 
1813 	if (unlikely(btrfs_header_level(leaf) != 0)) {
1814 		generic_err(leaf, 0,
1815 			"invalid level for leaf, have %d expect 0",
1816 			btrfs_header_level(leaf));
1817 		return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1818 	}
1819 
1820 	/*
1821 	 * Extent buffers from a relocation tree have a owner field that
1822 	 * corresponds to the subvolume tree they are based on. So just from an
1823 	 * extent buffer alone we can not find out what is the id of the
1824 	 * corresponding subvolume tree, so we can not figure out if the extent
1825 	 * buffer corresponds to the root of the relocation tree or not. So
1826 	 * skip this check for relocation trees.
1827 	 */
1828 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1829 		u64 owner = btrfs_header_owner(leaf);
1830 
1831 		/* These trees must never be empty */
1832 		if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1833 			     owner == BTRFS_CHUNK_TREE_OBJECTID ||
1834 			     owner == BTRFS_DEV_TREE_OBJECTID ||
1835 			     owner == BTRFS_FS_TREE_OBJECTID ||
1836 			     owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1837 			generic_err(leaf, 0,
1838 			"invalid root, root %llu must never be empty",
1839 				    owner);
1840 			return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1841 		}
1842 
1843 		/* Unknown tree */
1844 		if (unlikely(owner == 0)) {
1845 			generic_err(leaf, 0,
1846 				"invalid owner, root 0 is not defined");
1847 			return BTRFS_TREE_BLOCK_INVALID_OWNER;
1848 		}
1849 
1850 		/* EXTENT_TREE_V2 can have empty extent trees. */
1851 		if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1852 			return BTRFS_TREE_BLOCK_CLEAN;
1853 
1854 		if (unlikely(owner == BTRFS_EXTENT_TREE_OBJECTID)) {
1855 			generic_err(leaf, 0,
1856 			"invalid root, root %llu must never be empty",
1857 				    owner);
1858 			return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1859 		}
1860 
1861 		return BTRFS_TREE_BLOCK_CLEAN;
1862 	}
1863 
1864 	if (unlikely(nritems == 0))
1865 		return BTRFS_TREE_BLOCK_CLEAN;
1866 
1867 	/*
1868 	 * Check the following things to make sure this is a good leaf, and
1869 	 * leaf users won't need to bother with similar sanity checks:
1870 	 *
1871 	 * 1) key ordering
1872 	 * 2) item offset and size
1873 	 *    No overlap, no hole, all inside the leaf.
1874 	 * 3) item content
1875 	 *    If possible, do comprehensive sanity check.
1876 	 *    NOTE: All checks must only rely on the item data itself.
1877 	 */
1878 	for (slot = 0; slot < nritems; slot++) {
1879 		u32 item_end_expected;
1880 		u64 item_data_end;
1881 
1882 		btrfs_item_key_to_cpu(leaf, &key, slot);
1883 
1884 		/* Make sure the keys are in the right order */
1885 		if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
1886 			generic_err(leaf, slot,
1887 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1888 				prev_key.objectid, prev_key.type,
1889 				prev_key.offset, key.objectid, key.type,
1890 				key.offset);
1891 			return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
1892 		}
1893 
1894 		item_data_end = (u64)btrfs_item_offset(leaf, slot) +
1895 				btrfs_item_size(leaf, slot);
1896 		/*
1897 		 * Make sure the offset and ends are right, remember that the
1898 		 * item data starts at the end of the leaf and grows towards the
1899 		 * front.
1900 		 */
1901 		if (slot == 0)
1902 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1903 		else
1904 			item_end_expected = btrfs_item_offset(leaf,
1905 								 slot - 1);
1906 		if (unlikely(item_data_end != item_end_expected)) {
1907 			generic_err(leaf, slot,
1908 				"unexpected item end, have %llu expect %u",
1909 				item_data_end, item_end_expected);
1910 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1911 		}
1912 
1913 		/*
1914 		 * Check to make sure that we don't point outside of the leaf,
1915 		 * just in case all the items are consistent to each other, but
1916 		 * all point outside of the leaf.
1917 		 */
1918 		if (unlikely(item_data_end > BTRFS_LEAF_DATA_SIZE(fs_info))) {
1919 			generic_err(leaf, slot,
1920 			"slot end outside of leaf, have %llu expect range [0, %u]",
1921 				item_data_end, BTRFS_LEAF_DATA_SIZE(fs_info));
1922 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1923 		}
1924 
1925 		/* Also check if the item pointer overlaps with btrfs item. */
1926 		if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
1927 			     btrfs_item_nr_offset(leaf, slot) + sizeof(struct btrfs_item))) {
1928 			generic_err(leaf, slot,
1929 		"slot overlaps with its data, item end %lu data start %lu",
1930 				btrfs_item_nr_offset(leaf, slot) +
1931 				sizeof(struct btrfs_item),
1932 				btrfs_item_ptr_offset(leaf, slot));
1933 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
1934 		}
1935 
1936 		/*
1937 		 * We only want to do this if WRITTEN is set, otherwise the leaf
1938 		 * may be in some intermediate state and won't appear valid.
1939 		 */
1940 		if (btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_WRITTEN)) {
1941 			enum btrfs_tree_block_status ret;
1942 
1943 			/*
1944 			 * Check if the item size and content meet other
1945 			 * criteria
1946 			 */
1947 			ret = check_leaf_item(leaf, &key, slot, &prev_key);
1948 			if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1949 				return ret;
1950 		}
1951 
1952 		prev_key.objectid = key.objectid;
1953 		prev_key.type = key.type;
1954 		prev_key.offset = key.offset;
1955 	}
1956 
1957 	return BTRFS_TREE_BLOCK_CLEAN;
1958 }
1959 
btrfs_check_leaf(struct extent_buffer * leaf)1960 int btrfs_check_leaf(struct extent_buffer *leaf)
1961 {
1962 	enum btrfs_tree_block_status ret;
1963 
1964 	ret = __btrfs_check_leaf(leaf);
1965 	if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
1966 		return -EUCLEAN;
1967 	return 0;
1968 }
1969 ALLOW_ERROR_INJECTION(btrfs_check_leaf, ERRNO);
1970 
__btrfs_check_node(struct extent_buffer * node)1971 enum btrfs_tree_block_status __btrfs_check_node(struct extent_buffer *node)
1972 {
1973 	struct btrfs_fs_info *fs_info = node->fs_info;
1974 	unsigned long nr = btrfs_header_nritems(node);
1975 	struct btrfs_key key, next_key;
1976 	int slot;
1977 	int level = btrfs_header_level(node);
1978 	u64 bytenr;
1979 
1980 	if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
1981 		generic_err(node, 0,
1982 			"invalid level for node, have %d expect [1, %d]",
1983 			level, BTRFS_MAX_LEVEL - 1);
1984 		return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1985 	}
1986 	if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
1987 		btrfs_crit(fs_info,
1988 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1989 			   btrfs_header_owner(node), node->start,
1990 			   nr == 0 ? "small" : "large", nr,
1991 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1992 		return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1993 	}
1994 
1995 	for (slot = 0; slot < nr - 1; slot++) {
1996 		bytenr = btrfs_node_blockptr(node, slot);
1997 		btrfs_node_key_to_cpu(node, &key, slot);
1998 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1999 
2000 		if (unlikely(!bytenr)) {
2001 			generic_err(node, slot,
2002 				"invalid NULL node pointer");
2003 			return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
2004 		}
2005 		if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
2006 			generic_err(node, slot,
2007 			"unaligned pointer, have %llu should be aligned to %u",
2008 				bytenr, fs_info->sectorsize);
2009 			return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
2010 		}
2011 
2012 		if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
2013 			generic_err(node, slot,
2014 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
2015 				key.objectid, key.type, key.offset,
2016 				next_key.objectid, next_key.type,
2017 				next_key.offset);
2018 			return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
2019 		}
2020 	}
2021 	return BTRFS_TREE_BLOCK_CLEAN;
2022 }
2023 
btrfs_check_node(struct extent_buffer * node)2024 int btrfs_check_node(struct extent_buffer *node)
2025 {
2026 	enum btrfs_tree_block_status ret;
2027 
2028 	ret = __btrfs_check_node(node);
2029 	if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
2030 		return -EUCLEAN;
2031 	return 0;
2032 }
2033 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
2034 
btrfs_check_eb_owner(const struct extent_buffer * eb,u64 root_owner)2035 int btrfs_check_eb_owner(const struct extent_buffer *eb, u64 root_owner)
2036 {
2037 	const bool is_subvol = is_fstree(root_owner);
2038 	const u64 eb_owner = btrfs_header_owner(eb);
2039 
2040 	/*
2041 	 * Skip dummy fs, as selftests don't create unique ebs for each dummy
2042 	 * root.
2043 	 */
2044 	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &eb->fs_info->fs_state))
2045 		return 0;
2046 	/*
2047 	 * There are several call sites (backref walking, qgroup, and data
2048 	 * reloc) passing 0 as @root_owner, as they are not holding the
2049 	 * tree root.  In that case, we can not do a reliable ownership check,
2050 	 * so just exit.
2051 	 */
2052 	if (root_owner == 0)
2053 		return 0;
2054 	/*
2055 	 * These trees use key.offset as their owner, our callers don't have
2056 	 * the extra capacity to pass key.offset here.  So we just skip them.
2057 	 */
2058 	if (root_owner == BTRFS_TREE_LOG_OBJECTID ||
2059 	    root_owner == BTRFS_TREE_RELOC_OBJECTID)
2060 		return 0;
2061 
2062 	if (!is_subvol) {
2063 		/* For non-subvolume trees, the eb owner should match root owner */
2064 		if (unlikely(root_owner != eb_owner)) {
2065 			btrfs_crit(eb->fs_info,
2066 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect %llu",
2067 				btrfs_header_level(eb) == 0 ? "leaf" : "node",
2068 				root_owner, btrfs_header_bytenr(eb), eb_owner,
2069 				root_owner);
2070 			return -EUCLEAN;
2071 		}
2072 		return 0;
2073 	}
2074 
2075 	/*
2076 	 * For subvolume trees, owners can mismatch, but they should all belong
2077 	 * to subvolume trees.
2078 	 */
2079 	if (unlikely(is_subvol != is_fstree(eb_owner))) {
2080 		btrfs_crit(eb->fs_info,
2081 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect [%llu, %llu]",
2082 			btrfs_header_level(eb) == 0 ? "leaf" : "node",
2083 			root_owner, btrfs_header_bytenr(eb), eb_owner,
2084 			BTRFS_FIRST_FREE_OBJECTID, BTRFS_LAST_FREE_OBJECTID);
2085 		return -EUCLEAN;
2086 	}
2087 	return 0;
2088 }
2089 
btrfs_verify_level_key(struct extent_buffer * eb,int level,struct btrfs_key * first_key,u64 parent_transid)2090 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
2091 			   struct btrfs_key *first_key, u64 parent_transid)
2092 {
2093 	struct btrfs_fs_info *fs_info = eb->fs_info;
2094 	int found_level;
2095 	struct btrfs_key found_key;
2096 	int ret;
2097 
2098 	found_level = btrfs_header_level(eb);
2099 	if (found_level != level) {
2100 		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2101 		     KERN_ERR "BTRFS: tree level check failed\n");
2102 		btrfs_err(fs_info,
2103 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
2104 			  eb->start, level, found_level);
2105 		return -EIO;
2106 	}
2107 
2108 	if (!first_key)
2109 		return 0;
2110 
2111 	/*
2112 	 * For live tree block (new tree blocks in current transaction),
2113 	 * we need proper lock context to avoid race, which is impossible here.
2114 	 * So we only checks tree blocks which is read from disk, whose
2115 	 * generation <= fs_info->last_trans_committed.
2116 	 */
2117 	if (btrfs_header_generation(eb) > fs_info->last_trans_committed)
2118 		return 0;
2119 
2120 	/* We have @first_key, so this @eb must have at least one item */
2121 	if (btrfs_header_nritems(eb) == 0) {
2122 		btrfs_err(fs_info,
2123 		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
2124 			  eb->start);
2125 		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
2126 		return -EUCLEAN;
2127 	}
2128 
2129 	if (found_level)
2130 		btrfs_node_key_to_cpu(eb, &found_key, 0);
2131 	else
2132 		btrfs_item_key_to_cpu(eb, &found_key, 0);
2133 	ret = btrfs_comp_cpu_keys(first_key, &found_key);
2134 
2135 	if (ret) {
2136 		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2137 		     KERN_ERR "BTRFS: tree first key check failed\n");
2138 		btrfs_err(fs_info,
2139 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
2140 			  eb->start, parent_transid, first_key->objectid,
2141 			  first_key->type, first_key->offset,
2142 			  found_key.objectid, found_key.type,
2143 			  found_key.offset);
2144 	}
2145 	return ret;
2146 }
2147