xref: /linux/fs/btrfs/tree-checker.c (revision 0eb4aaa230d725fa9b1cd758c0f17abca5597af6)
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 "compression.h"
25 #include "volumes.h"
26 #include "misc.h"
27 #include "fs.h"
28 #include "accessors.h"
29 #include "file-item.h"
30 #include "inode-item.h"
31 #include "dir-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 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
69 	btrfs_crit(fs_info,
70 		"corrupt %s: root=%llu block=%llu slot=%d, %pV",
71 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
72 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
73 	va_end(args);
74 }
75 
76 /*
77  * Customized reporter for extent data item, since its key objectid and
78  * offset has its own meaning.
79  */
80 __printf(3, 4)
81 __cold
file_extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)82 static void file_extent_err(const struct extent_buffer *eb, int slot,
83 			    const char *fmt, ...)
84 {
85 	const struct btrfs_fs_info *fs_info = eb->fs_info;
86 	struct btrfs_key key;
87 	struct va_format vaf;
88 	va_list args;
89 
90 	btrfs_item_key_to_cpu(eb, &key, slot);
91 	va_start(args, fmt);
92 
93 	vaf.fmt = fmt;
94 	vaf.va = &args;
95 
96 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
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 
file_extent_end(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_file_extent_item * extent)120 static u64 file_extent_end(struct extent_buffer *leaf,
121 			   struct btrfs_key *key,
122 			   struct btrfs_file_extent_item *extent)
123 {
124 	u64 end;
125 	u64 len;
126 
127 	if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
128 		len = btrfs_file_extent_ram_bytes(leaf, extent);
129 		end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
130 	} else {
131 		len = btrfs_file_extent_num_bytes(leaf, extent);
132 		end = key->offset + len;
133 	}
134 	return end;
135 }
136 
137 /*
138  * Customized report for dir_item, the only new important information is
139  * key->objectid, which represents inode number
140  */
141 __printf(3, 4)
142 __cold
dir_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)143 static void dir_item_err(const struct extent_buffer *eb, int slot,
144 			 const char *fmt, ...)
145 {
146 	const struct btrfs_fs_info *fs_info = eb->fs_info;
147 	struct btrfs_key key;
148 	struct va_format vaf;
149 	va_list args;
150 
151 	btrfs_item_key_to_cpu(eb, &key, slot);
152 	va_start(args, fmt);
153 
154 	vaf.fmt = fmt;
155 	vaf.va = &args;
156 
157 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
158 	btrfs_crit(fs_info,
159 		"corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
160 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
161 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
162 		key.objectid, &vaf);
163 	va_end(args);
164 }
165 
166 /*
167  * This functions checks prev_key->objectid, to ensure current key and prev_key
168  * share the same objectid as inode number.
169  *
170  * This is to detect missing INODE_ITEM in subvolume trees.
171  *
172  * Return true if everything is OK or we don't need to check.
173  * Return false if anything is wrong.
174  */
check_prev_ino(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)175 static bool check_prev_ino(struct extent_buffer *leaf,
176 			   struct btrfs_key *key, int slot,
177 			   struct btrfs_key *prev_key)
178 {
179 	/* No prev key, skip check */
180 	if (slot == 0)
181 		return true;
182 
183 	/* Only these key->types needs to be checked */
184 	ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
185 	       key->type == BTRFS_INODE_REF_KEY ||
186 	       key->type == BTRFS_DIR_INDEX_KEY ||
187 	       key->type == BTRFS_DIR_ITEM_KEY ||
188 	       key->type == BTRFS_EXTENT_DATA_KEY);
189 
190 	/*
191 	 * Only subvolume trees along with their reloc trees need this check.
192 	 * Things like log tree doesn't follow this ino requirement.
193 	 */
194 	if (!is_fstree(btrfs_header_owner(leaf)))
195 		return true;
196 
197 	if (key->objectid == prev_key->objectid)
198 		return true;
199 
200 	/* Error found */
201 	dir_item_err(leaf, slot,
202 		"invalid previous key objectid, have %llu expect %llu",
203 		prev_key->objectid, key->objectid);
204 	return false;
205 }
check_extent_data_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)206 static int check_extent_data_item(struct extent_buffer *leaf,
207 				  struct btrfs_key *key, int slot,
208 				  struct btrfs_key *prev_key)
209 {
210 	struct btrfs_fs_info *fs_info = leaf->fs_info;
211 	struct btrfs_file_extent_item *fi;
212 	u32 sectorsize = fs_info->sectorsize;
213 	u32 item_size = btrfs_item_size(leaf, slot);
214 	u64 extent_end;
215 
216 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
217 		file_extent_err(leaf, slot,
218 "unaligned file_offset for file extent, have %llu should be aligned to %u",
219 			key->offset, sectorsize);
220 		return -EUCLEAN;
221 	}
222 
223 	/*
224 	 * Previous key must have the same key->objectid (ino).
225 	 * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
226 	 * But if objectids mismatch, it means we have a missing
227 	 * INODE_ITEM.
228 	 */
229 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
230 		return -EUCLEAN;
231 
232 	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
233 
234 	/*
235 	 * Make sure the item contains at least inline header, so the file
236 	 * extent type is not some garbage.
237 	 */
238 	if (unlikely(item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START)) {
239 		file_extent_err(leaf, slot,
240 				"invalid item size, have %u expect [%zu, %u)",
241 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
242 				SZ_4K);
243 		return -EUCLEAN;
244 	}
245 	if (unlikely(btrfs_file_extent_type(leaf, fi) >=
246 		     BTRFS_NR_FILE_EXTENT_TYPES)) {
247 		file_extent_err(leaf, slot,
248 		"invalid type for file extent, have %u expect range [0, %u]",
249 			btrfs_file_extent_type(leaf, fi),
250 			BTRFS_NR_FILE_EXTENT_TYPES - 1);
251 		return -EUCLEAN;
252 	}
253 
254 	/*
255 	 * Support for new compression/encryption must introduce incompat flag,
256 	 * and must be caught in open_ctree().
257 	 */
258 	if (unlikely(btrfs_file_extent_compression(leaf, fi) >=
259 		     BTRFS_NR_COMPRESS_TYPES)) {
260 		file_extent_err(leaf, slot,
261 	"invalid compression for file extent, have %u expect range [0, %u]",
262 			btrfs_file_extent_compression(leaf, fi),
263 			BTRFS_NR_COMPRESS_TYPES - 1);
264 		return -EUCLEAN;
265 	}
266 	if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
267 		file_extent_err(leaf, slot,
268 			"invalid encryption for file extent, have %u expect 0",
269 			btrfs_file_extent_encryption(leaf, fi));
270 		return -EUCLEAN;
271 	}
272 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
273 		/* Inline extent must have 0 as key offset */
274 		if (unlikely(key->offset)) {
275 			file_extent_err(leaf, slot,
276 		"invalid file_offset for inline file extent, have %llu expect 0",
277 				key->offset);
278 			return -EUCLEAN;
279 		}
280 
281 		/* Compressed inline extent has no on-disk size, skip it */
282 		if (btrfs_file_extent_compression(leaf, fi) !=
283 		    BTRFS_COMPRESS_NONE)
284 			return 0;
285 
286 		/* Uncompressed inline extent size must match item size */
287 		if (unlikely(item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
288 					  btrfs_file_extent_ram_bytes(leaf, fi))) {
289 			file_extent_err(leaf, slot,
290 	"invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
291 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
292 				btrfs_file_extent_ram_bytes(leaf, fi));
293 			return -EUCLEAN;
294 		}
295 		return 0;
296 	}
297 
298 	/* Regular or preallocated extent has fixed item size */
299 	if (unlikely(item_size != sizeof(*fi))) {
300 		file_extent_err(leaf, slot,
301 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
302 			item_size, sizeof(*fi));
303 		return -EUCLEAN;
304 	}
305 	if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
306 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
307 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
308 		     CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
309 		     CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize)))
310 		return -EUCLEAN;
311 
312 	/* Catch extent end overflow */
313 	if (unlikely(check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
314 					key->offset, &extent_end))) {
315 		file_extent_err(leaf, slot,
316 	"extent end overflow, have file offset %llu extent num bytes %llu",
317 				key->offset,
318 				btrfs_file_extent_num_bytes(leaf, fi));
319 		return -EUCLEAN;
320 	}
321 
322 	/*
323 	 * Check that no two consecutive file extent items, in the same leaf,
324 	 * present ranges that overlap each other.
325 	 */
326 	if (slot > 0 &&
327 	    prev_key->objectid == key->objectid &&
328 	    prev_key->type == BTRFS_EXTENT_DATA_KEY) {
329 		struct btrfs_file_extent_item *prev_fi;
330 		u64 prev_end;
331 
332 		prev_fi = btrfs_item_ptr(leaf, slot - 1,
333 					 struct btrfs_file_extent_item);
334 		prev_end = file_extent_end(leaf, prev_key, prev_fi);
335 		if (unlikely(prev_end > key->offset)) {
336 			file_extent_err(leaf, slot - 1,
337 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
338 					prev_end, key->offset);
339 			return -EUCLEAN;
340 		}
341 	}
342 
343 	/*
344 	 * For non-compressed data extents, ram_bytes should match its
345 	 * disk_num_bytes.
346 	 * However we do not really utilize ram_bytes in this case, so this check
347 	 * is only optional for DEBUG builds for developers to catch the
348 	 * unexpected behaviors.
349 	 */
350 	if (IS_ENABLED(CONFIG_BTRFS_DEBUG) &&
351 	    btrfs_file_extent_compression(leaf, fi) == BTRFS_COMPRESS_NONE &&
352 	    btrfs_file_extent_disk_bytenr(leaf, fi)) {
353 		if (WARN_ON(btrfs_file_extent_ram_bytes(leaf, fi) !=
354 			    btrfs_file_extent_disk_num_bytes(leaf, fi)))
355 			file_extent_err(leaf, slot,
356 "mismatch ram_bytes (%llu) and disk_num_bytes (%llu) for non-compressed extent",
357 					btrfs_file_extent_ram_bytes(leaf, fi),
358 					btrfs_file_extent_disk_num_bytes(leaf, fi));
359 	}
360 
361 	return 0;
362 }
363 
check_csum_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)364 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
365 			   int slot, struct btrfs_key *prev_key)
366 {
367 	struct btrfs_fs_info *fs_info = leaf->fs_info;
368 	u32 sectorsize = fs_info->sectorsize;
369 	const u32 csumsize = fs_info->csum_size;
370 
371 	if (unlikely(key->objectid != BTRFS_EXTENT_CSUM_OBJECTID)) {
372 		generic_err(leaf, slot,
373 		"invalid key objectid for csum item, have %llu expect %llu",
374 			key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
375 		return -EUCLEAN;
376 	}
377 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
378 		generic_err(leaf, slot,
379 	"unaligned key offset for csum item, have %llu should be aligned to %u",
380 			key->offset, sectorsize);
381 		return -EUCLEAN;
382 	}
383 	if (unlikely(!IS_ALIGNED(btrfs_item_size(leaf, slot), csumsize))) {
384 		generic_err(leaf, slot,
385 	"unaligned item size for csum item, have %u should be aligned to %u",
386 			btrfs_item_size(leaf, slot), csumsize);
387 		return -EUCLEAN;
388 	}
389 	if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
390 		u64 prev_csum_end;
391 		u32 prev_item_size;
392 
393 		prev_item_size = btrfs_item_size(leaf, slot - 1);
394 		prev_csum_end = (prev_item_size / csumsize) * sectorsize;
395 		prev_csum_end += prev_key->offset;
396 		if (unlikely(prev_csum_end > key->offset)) {
397 			generic_err(leaf, slot - 1,
398 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
399 				    prev_csum_end, key->offset);
400 			return -EUCLEAN;
401 		}
402 	}
403 	return 0;
404 }
405 
406 /* Inode item error output has the same format as dir_item_err() */
407 #define inode_item_err(eb, slot, fmt, ...)			\
408 	dir_item_err(eb, slot, fmt, __VA_ARGS__)
409 
check_inode_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)410 static int check_inode_key(struct extent_buffer *leaf, struct btrfs_key *key,
411 			   int slot)
412 {
413 	struct btrfs_key item_key;
414 	bool is_inode_item;
415 
416 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
417 	is_inode_item = (item_key.type == BTRFS_INODE_ITEM_KEY);
418 
419 	/* For XATTR_ITEM, location key should be all 0 */
420 	if (item_key.type == BTRFS_XATTR_ITEM_KEY) {
421 		if (unlikely(key->objectid != 0 || key->type != 0 ||
422 			     key->offset != 0))
423 			return -EUCLEAN;
424 		return 0;
425 	}
426 
427 	if (unlikely((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
428 		      key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
429 		     key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
430 		     key->objectid != BTRFS_FREE_INO_OBJECTID)) {
431 		if (is_inode_item) {
432 			generic_err(leaf, slot,
433 	"invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
434 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
435 				BTRFS_FIRST_FREE_OBJECTID,
436 				BTRFS_LAST_FREE_OBJECTID,
437 				BTRFS_FREE_INO_OBJECTID);
438 		} else {
439 			dir_item_err(leaf, slot,
440 "invalid location key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
441 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
442 				BTRFS_FIRST_FREE_OBJECTID,
443 				BTRFS_LAST_FREE_OBJECTID,
444 				BTRFS_FREE_INO_OBJECTID);
445 		}
446 		return -EUCLEAN;
447 	}
448 	if (unlikely(key->offset != 0)) {
449 		if (is_inode_item)
450 			inode_item_err(leaf, slot,
451 				       "invalid key offset: has %llu expect 0",
452 				       key->offset);
453 		else
454 			dir_item_err(leaf, slot,
455 				"invalid location key offset:has %llu expect 0",
456 				key->offset);
457 		return -EUCLEAN;
458 	}
459 	return 0;
460 }
461 
check_root_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)462 static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
463 			  int slot)
464 {
465 	struct btrfs_key item_key;
466 	bool is_root_item;
467 
468 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
469 	is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
470 
471 	/*
472 	 * Bad rootid for reloc trees.
473 	 *
474 	 * Reloc trees are only for subvolume trees, other trees only need
475 	 * to be COWed to be relocated.
476 	 */
477 	if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
478 		     !is_fstree(key->offset))) {
479 		generic_err(leaf, slot,
480 		"invalid reloc tree for root %lld, root id is not a subvolume tree",
481 			    key->offset);
482 		return -EUCLEAN;
483 	}
484 
485 	/* No such tree id */
486 	if (unlikely(key->objectid == 0)) {
487 		if (is_root_item)
488 			generic_err(leaf, slot, "invalid root id 0");
489 		else
490 			dir_item_err(leaf, slot,
491 				     "invalid location key root id 0");
492 		return -EUCLEAN;
493 	}
494 
495 	/* DIR_ITEM/INDEX/INODE_REF is not allowed to point to non-fs trees */
496 	if (unlikely(!is_fstree(key->objectid) && !is_root_item)) {
497 		dir_item_err(leaf, slot,
498 		"invalid location key objectid, have %llu expect [%llu, %llu]",
499 				key->objectid, BTRFS_FIRST_FREE_OBJECTID,
500 				BTRFS_LAST_FREE_OBJECTID);
501 		return -EUCLEAN;
502 	}
503 
504 	/*
505 	 * ROOT_ITEM with non-zero offset means this is a snapshot, created at
506 	 * @offset transid.
507 	 * Furthermore, for location key in DIR_ITEM, its offset is always -1.
508 	 *
509 	 * So here we only check offset for reloc tree whose key->offset must
510 	 * be a valid tree.
511 	 */
512 	if (unlikely(key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
513 		     key->offset == 0)) {
514 		generic_err(leaf, slot, "invalid root id 0 for reloc tree");
515 		return -EUCLEAN;
516 	}
517 	return 0;
518 }
519 
check_dir_item(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_key * prev_key,int slot)520 static int check_dir_item(struct extent_buffer *leaf,
521 			  struct btrfs_key *key, struct btrfs_key *prev_key,
522 			  int slot)
523 {
524 	struct btrfs_fs_info *fs_info = leaf->fs_info;
525 	struct btrfs_dir_item *di;
526 	u32 item_size = btrfs_item_size(leaf, slot);
527 	u32 cur = 0;
528 
529 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
530 		return -EUCLEAN;
531 
532 	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
533 	while (cur < item_size) {
534 		struct btrfs_key location_key;
535 		u32 name_len;
536 		u32 data_len;
537 		u32 max_name_len;
538 		u32 total_size;
539 		u32 name_hash;
540 		u8 dir_type;
541 		int ret;
542 
543 		/* header itself should not cross item boundary */
544 		if (unlikely(cur + sizeof(*di) > item_size)) {
545 			dir_item_err(leaf, slot,
546 		"dir item header crosses item boundary, have %zu boundary %u",
547 				cur + sizeof(*di), item_size);
548 			return -EUCLEAN;
549 		}
550 
551 		/* Location key check */
552 		btrfs_dir_item_key_to_cpu(leaf, di, &location_key);
553 		if (location_key.type == BTRFS_ROOT_ITEM_KEY) {
554 			ret = check_root_key(leaf, &location_key, slot);
555 			if (unlikely(ret < 0))
556 				return ret;
557 		} else if (location_key.type == BTRFS_INODE_ITEM_KEY ||
558 			   location_key.type == 0) {
559 			ret = check_inode_key(leaf, &location_key, slot);
560 			if (unlikely(ret < 0))
561 				return ret;
562 		} else {
563 			dir_item_err(leaf, slot,
564 			"invalid location key type, have %u, expect %u or %u",
565 				     location_key.type, BTRFS_ROOT_ITEM_KEY,
566 				     BTRFS_INODE_ITEM_KEY);
567 			return -EUCLEAN;
568 		}
569 
570 		/* dir type check */
571 		dir_type = btrfs_dir_ftype(leaf, di);
572 		if (unlikely(dir_type <= BTRFS_FT_UNKNOWN ||
573 			     dir_type >= BTRFS_FT_MAX)) {
574 			dir_item_err(leaf, slot,
575 			"invalid dir item type, have %u expect (0, %u)",
576 				dir_type, BTRFS_FT_MAX);
577 			return -EUCLEAN;
578 		}
579 
580 		if (unlikely(key->type == BTRFS_XATTR_ITEM_KEY &&
581 			     dir_type != BTRFS_FT_XATTR)) {
582 			dir_item_err(leaf, slot,
583 		"invalid dir item type for XATTR key, have %u expect %u",
584 				dir_type, BTRFS_FT_XATTR);
585 			return -EUCLEAN;
586 		}
587 		if (unlikely(dir_type == BTRFS_FT_XATTR &&
588 			     key->type != BTRFS_XATTR_ITEM_KEY)) {
589 			dir_item_err(leaf, slot,
590 			"xattr dir type found for non-XATTR key");
591 			return -EUCLEAN;
592 		}
593 		if (dir_type == BTRFS_FT_XATTR)
594 			max_name_len = XATTR_NAME_MAX;
595 		else
596 			max_name_len = BTRFS_NAME_LEN;
597 
598 		/* Name/data length check */
599 		name_len = btrfs_dir_name_len(leaf, di);
600 		data_len = btrfs_dir_data_len(leaf, di);
601 		if (unlikely(name_len > max_name_len)) {
602 			dir_item_err(leaf, slot,
603 			"dir item name len too long, have %u max %u",
604 				name_len, max_name_len);
605 			return -EUCLEAN;
606 		}
607 		if (unlikely(name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info))) {
608 			dir_item_err(leaf, slot,
609 			"dir item name and data len too long, have %u max %u",
610 				name_len + data_len,
611 				BTRFS_MAX_XATTR_SIZE(fs_info));
612 			return -EUCLEAN;
613 		}
614 
615 		if (unlikely(data_len && dir_type != BTRFS_FT_XATTR)) {
616 			dir_item_err(leaf, slot,
617 			"dir item with invalid data len, have %u expect 0",
618 				data_len);
619 			return -EUCLEAN;
620 		}
621 
622 		total_size = sizeof(*di) + name_len + data_len;
623 
624 		/* header and name/data should not cross item boundary */
625 		if (unlikely(cur + total_size > item_size)) {
626 			dir_item_err(leaf, slot,
627 		"dir item data crosses item boundary, have %u boundary %u",
628 				cur + total_size, item_size);
629 			return -EUCLEAN;
630 		}
631 
632 		/*
633 		 * Special check for XATTR/DIR_ITEM, as key->offset is name
634 		 * hash, should match its name
635 		 */
636 		if (key->type == BTRFS_DIR_ITEM_KEY ||
637 		    key->type == BTRFS_XATTR_ITEM_KEY) {
638 			char namebuf[MAX(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
639 
640 			read_extent_buffer(leaf, namebuf,
641 					(unsigned long)(di + 1), name_len);
642 			name_hash = btrfs_name_hash(namebuf, name_len);
643 			if (unlikely(key->offset != name_hash)) {
644 				dir_item_err(leaf, slot,
645 		"name hash mismatch with key, have 0x%016x expect 0x%016llx",
646 					name_hash, key->offset);
647 				return -EUCLEAN;
648 			}
649 		}
650 		cur += total_size;
651 		di = (struct btrfs_dir_item *)((void *)di + total_size);
652 	}
653 	return 0;
654 }
655 
656 __printf(3, 4)
657 __cold
block_group_err(const struct extent_buffer * eb,int slot,const char * fmt,...)658 static void block_group_err(const struct extent_buffer *eb, int slot,
659 			    const char *fmt, ...)
660 {
661 	const struct btrfs_fs_info *fs_info = eb->fs_info;
662 	struct btrfs_key key;
663 	struct va_format vaf;
664 	va_list args;
665 
666 	btrfs_item_key_to_cpu(eb, &key, slot);
667 	va_start(args, fmt);
668 
669 	vaf.fmt = fmt;
670 	vaf.va = &args;
671 
672 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
673 	btrfs_crit(fs_info,
674 	"corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
675 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
676 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
677 		key.objectid, key.offset, &vaf);
678 	va_end(args);
679 }
680 
check_block_group_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)681 static int check_block_group_item(struct extent_buffer *leaf,
682 				  struct btrfs_key *key, int slot)
683 {
684 	struct btrfs_fs_info *fs_info = leaf->fs_info;
685 	struct btrfs_block_group_item bgi;
686 	u32 item_size = btrfs_item_size(leaf, slot);
687 	u64 chunk_objectid;
688 	u64 flags;
689 	u64 type;
690 
691 	/*
692 	 * Here we don't really care about alignment since extent allocator can
693 	 * handle it.  We care more about the size.
694 	 */
695 	if (unlikely(key->offset == 0)) {
696 		block_group_err(leaf, slot,
697 				"invalid block group size 0");
698 		return -EUCLEAN;
699 	}
700 
701 	if (unlikely(item_size != sizeof(bgi))) {
702 		block_group_err(leaf, slot,
703 			"invalid item size, have %u expect %zu",
704 				item_size, sizeof(bgi));
705 		return -EUCLEAN;
706 	}
707 
708 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
709 			   sizeof(bgi));
710 	chunk_objectid = btrfs_stack_block_group_chunk_objectid(&bgi);
711 	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
712 		/*
713 		 * We don't init the nr_global_roots until we load the global
714 		 * roots, so this could be 0 at mount time.  If it's 0 we'll
715 		 * just assume we're fine, and later we'll check against our
716 		 * actual value.
717 		 */
718 		if (unlikely(fs_info->nr_global_roots &&
719 			     chunk_objectid >= fs_info->nr_global_roots)) {
720 			block_group_err(leaf, slot,
721 	"invalid block group global root id, have %llu, needs to be <= %llu",
722 					chunk_objectid,
723 					fs_info->nr_global_roots);
724 			return -EUCLEAN;
725 		}
726 	} else if (unlikely(chunk_objectid != BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
727 		block_group_err(leaf, slot,
728 		"invalid block group chunk objectid, have %llu expect %llu",
729 				btrfs_stack_block_group_chunk_objectid(&bgi),
730 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
731 		return -EUCLEAN;
732 	}
733 
734 	if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
735 		block_group_err(leaf, slot,
736 			"invalid block group used, have %llu expect [0, %llu)",
737 				btrfs_stack_block_group_used(&bgi), key->offset);
738 		return -EUCLEAN;
739 	}
740 
741 	flags = btrfs_stack_block_group_flags(&bgi);
742 	if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
743 		block_group_err(leaf, slot,
744 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
745 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
746 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
747 		return -EUCLEAN;
748 	}
749 
750 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
751 	if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
752 		     type != BTRFS_BLOCK_GROUP_METADATA &&
753 		     type != BTRFS_BLOCK_GROUP_SYSTEM &&
754 		     type != (BTRFS_BLOCK_GROUP_METADATA |
755 			      BTRFS_BLOCK_GROUP_DATA))) {
756 		block_group_err(leaf, slot,
757 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
758 			type, hweight64(type),
759 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
760 			BTRFS_BLOCK_GROUP_SYSTEM,
761 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
762 		return -EUCLEAN;
763 	}
764 	return 0;
765 }
766 
767 __printf(5, 6)
768 __cold
chunk_err(const struct btrfs_fs_info * fs_info,const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,const char * fmt,...)769 static void chunk_err(const struct btrfs_fs_info *fs_info,
770 		      const struct extent_buffer *leaf,
771 		      const struct btrfs_chunk *chunk, u64 logical,
772 		      const char *fmt, ...)
773 {
774 	bool is_sb = !leaf;
775 	struct va_format vaf;
776 	va_list args;
777 	int i;
778 	int slot = -1;
779 
780 	if (!is_sb) {
781 		/*
782 		 * Get the slot number by iterating through all slots, this
783 		 * would provide better readability.
784 		 */
785 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
786 			if (btrfs_item_ptr_offset(leaf, i) ==
787 					(unsigned long)chunk) {
788 				slot = i;
789 				break;
790 			}
791 		}
792 	}
793 	va_start(args, fmt);
794 	vaf.fmt = fmt;
795 	vaf.va = &args;
796 
797 	if (is_sb)
798 		btrfs_crit(fs_info,
799 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
800 			   logical, &vaf);
801 	else
802 		btrfs_crit(fs_info,
803 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
804 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
805 			   logical, &vaf);
806 	va_end(args);
807 }
808 
809 /*
810  * The common chunk check which could also work on super block sys chunk array.
811  *
812  * If @leaf is NULL, then @chunk must be an on-stack chunk item.
813  * (For superblock sys_chunk array, and fs_info->sectorsize is unreliable)
814  *
815  * Return -EUCLEAN if anything is corrupted.
816  * Return 0 if everything is OK.
817  */
btrfs_check_chunk_valid(const struct btrfs_fs_info * fs_info,const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,u32 sectorsize)818 int btrfs_check_chunk_valid(const struct btrfs_fs_info *fs_info,
819 			    const struct extent_buffer *leaf,
820 			    const struct btrfs_chunk *chunk, u64 logical,
821 			    u32 sectorsize)
822 {
823 	u64 length;
824 	u64 chunk_end;
825 	u64 stripe_len;
826 	u16 num_stripes;
827 	u16 sub_stripes;
828 	u64 type;
829 	u64 features;
830 	u32 chunk_sector_size;
831 	bool mixed = false;
832 	int raid_index;
833 	int nparity;
834 	int ncopies;
835 
836 	if (leaf) {
837 		length = btrfs_chunk_length(leaf, chunk);
838 		stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
839 		num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
840 		sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
841 		type = btrfs_chunk_type(leaf, chunk);
842 		chunk_sector_size = btrfs_chunk_sector_size(leaf, chunk);
843 	} else {
844 		length = btrfs_stack_chunk_length(chunk);
845 		stripe_len = btrfs_stack_chunk_stripe_len(chunk);
846 		num_stripes = btrfs_stack_chunk_num_stripes(chunk);
847 		sub_stripes = btrfs_stack_chunk_sub_stripes(chunk);
848 		type = btrfs_stack_chunk_type(chunk);
849 		chunk_sector_size = btrfs_stack_chunk_sector_size(chunk);
850 	}
851 	raid_index = btrfs_bg_flags_to_raid_index(type);
852 	ncopies = btrfs_raid_array[raid_index].ncopies;
853 	nparity = btrfs_raid_array[raid_index].nparity;
854 
855 	if (unlikely(!num_stripes)) {
856 		chunk_err(fs_info, leaf, chunk, logical,
857 			  "invalid chunk num_stripes, have %u", num_stripes);
858 		return -EUCLEAN;
859 	}
860 	if (unlikely(num_stripes < ncopies)) {
861 		chunk_err(fs_info, leaf, chunk, logical,
862 			  "invalid chunk num_stripes < ncopies, have %u < %d",
863 			  num_stripes, ncopies);
864 		return -EUCLEAN;
865 	}
866 	if (unlikely(nparity && num_stripes == nparity)) {
867 		chunk_err(fs_info, leaf, chunk, logical,
868 			  "invalid chunk num_stripes == nparity, have %u == %d",
869 			  num_stripes, nparity);
870 		return -EUCLEAN;
871 	}
872 	if (unlikely(!IS_ALIGNED(logical, sectorsize))) {
873 		chunk_err(fs_info, leaf, chunk, logical,
874 		"invalid chunk logical, have %llu should aligned to %u",
875 			  logical, sectorsize);
876 		return -EUCLEAN;
877 	}
878 	if (unlikely(chunk_sector_size != sectorsize)) {
879 		chunk_err(fs_info, leaf, chunk, logical,
880 			  "invalid chunk sectorsize, have %u expect %u",
881 			  chunk_sector_size, sectorsize);
882 		return -EUCLEAN;
883 	}
884 	if (unlikely(!length || !IS_ALIGNED(length, sectorsize))) {
885 		chunk_err(fs_info, leaf, chunk, logical,
886 			  "invalid chunk length, have %llu", length);
887 		return -EUCLEAN;
888 	}
889 	if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
890 		chunk_err(fs_info, leaf, chunk, logical,
891 "invalid chunk logical start and length, have logical start %llu length %llu",
892 			  logical, length);
893 		return -EUCLEAN;
894 	}
895 	if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
896 		chunk_err(fs_info, leaf, chunk, logical,
897 			  "invalid chunk stripe length: %llu",
898 			  stripe_len);
899 		return -EUCLEAN;
900 	}
901 	/*
902 	 * We artificially limit the chunk size, so that the number of stripes
903 	 * inside a chunk can be fit into a U32.  The current limit (256G) is
904 	 * way too large for real world usage anyway, and it's also much larger
905 	 * than our existing limit (10G).
906 	 *
907 	 * Thus it should be a good way to catch obvious bitflips.
908 	 */
909 	if (unlikely(length >= btrfs_stripe_nr_to_offset(U32_MAX))) {
910 		chunk_err(fs_info, leaf, chunk, logical,
911 			  "chunk length too large: have %llu limit %llu",
912 			  length, btrfs_stripe_nr_to_offset(U32_MAX));
913 		return -EUCLEAN;
914 	}
915 	if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
916 			      BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
917 		chunk_err(fs_info, leaf, chunk, logical,
918 			  "unrecognized chunk type: 0x%llx",
919 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
920 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) & type);
921 		return -EUCLEAN;
922 	}
923 
924 	if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
925 		     (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
926 		chunk_err(fs_info, leaf, chunk, logical,
927 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
928 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
929 		return -EUCLEAN;
930 	}
931 	if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
932 		chunk_err(fs_info, leaf, chunk, logical,
933 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
934 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
935 		return -EUCLEAN;
936 	}
937 
938 	if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
939 		     (type & (BTRFS_BLOCK_GROUP_METADATA |
940 			      BTRFS_BLOCK_GROUP_DATA)))) {
941 		chunk_err(fs_info, leaf, chunk, logical,
942 			  "system chunk with data or metadata type: 0x%llx",
943 			  type);
944 		return -EUCLEAN;
945 	}
946 
947 	features = btrfs_super_incompat_flags(fs_info->super_copy);
948 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
949 		mixed = true;
950 
951 	if (!mixed) {
952 		if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
953 			     (type & BTRFS_BLOCK_GROUP_DATA))) {
954 			chunk_err(fs_info, leaf, chunk, logical,
955 			"mixed chunk type in non-mixed mode: 0x%llx", type);
956 			return -EUCLEAN;
957 		}
958 	}
959 
960 	if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
961 		      sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
962 		     (type & BTRFS_BLOCK_GROUP_RAID1 &&
963 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
964 		     (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
965 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
966 		     (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
967 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
968 		     (type & BTRFS_BLOCK_GROUP_RAID5 &&
969 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
970 		     (type & BTRFS_BLOCK_GROUP_RAID6 &&
971 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
972 		     (type & BTRFS_BLOCK_GROUP_DUP &&
973 		      num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
974 		     ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
975 		      num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
976 		chunk_err(fs_info, leaf, chunk, logical,
977 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
978 			num_stripes, sub_stripes,
979 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
980 		return -EUCLEAN;
981 	}
982 
983 	return 0;
984 }
985 
986 /*
987  * Enhanced version of chunk item checker.
988  *
989  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
990  * to work on super block sys_chunk_array which doesn't have full item ptr.
991  */
check_leaf_chunk_item(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_key * key,int slot)992 static int check_leaf_chunk_item(struct extent_buffer *leaf,
993 				 struct btrfs_chunk *chunk,
994 				 struct btrfs_key *key, int slot)
995 {
996 	struct btrfs_fs_info *fs_info = leaf->fs_info;
997 	int num_stripes;
998 
999 	if (unlikely(btrfs_item_size(leaf, slot) < sizeof(struct btrfs_chunk))) {
1000 		chunk_err(fs_info, leaf, chunk, key->offset,
1001 			"invalid chunk item size: have %u expect [%zu, %u)",
1002 			btrfs_item_size(leaf, slot),
1003 			sizeof(struct btrfs_chunk),
1004 			BTRFS_LEAF_DATA_SIZE(fs_info));
1005 		return -EUCLEAN;
1006 	}
1007 
1008 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
1009 	/* Let btrfs_check_chunk_valid() handle this error type */
1010 	if (num_stripes == 0)
1011 		goto out;
1012 
1013 	if (unlikely(btrfs_chunk_item_size(num_stripes) !=
1014 		     btrfs_item_size(leaf, slot))) {
1015 		chunk_err(fs_info, leaf, chunk, key->offset,
1016 			"invalid chunk item size: have %u expect %lu",
1017 			btrfs_item_size(leaf, slot),
1018 			btrfs_chunk_item_size(num_stripes));
1019 		return -EUCLEAN;
1020 	}
1021 out:
1022 	return btrfs_check_chunk_valid(fs_info, leaf, chunk, key->offset,
1023 				       fs_info->sectorsize);
1024 }
1025 
1026 __printf(3, 4)
1027 __cold
dev_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)1028 static void dev_item_err(const struct extent_buffer *eb, int slot,
1029 			 const char *fmt, ...)
1030 {
1031 	struct btrfs_key key;
1032 	struct va_format vaf;
1033 	va_list args;
1034 
1035 	btrfs_item_key_to_cpu(eb, &key, slot);
1036 	va_start(args, fmt);
1037 
1038 	vaf.fmt = fmt;
1039 	vaf.va = &args;
1040 
1041 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
1042 	btrfs_crit(eb->fs_info,
1043 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
1044 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1045 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
1046 		key.objectid, &vaf);
1047 	va_end(args);
1048 }
1049 
check_dev_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1050 static int check_dev_item(struct extent_buffer *leaf,
1051 			  struct btrfs_key *key, int slot)
1052 {
1053 	struct btrfs_dev_item *ditem;
1054 	const u32 item_size = btrfs_item_size(leaf, slot);
1055 
1056 	if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
1057 		dev_item_err(leaf, slot,
1058 			     "invalid objectid: has=%llu expect=%llu",
1059 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
1060 		return -EUCLEAN;
1061 	}
1062 
1063 	if (unlikely(item_size != sizeof(*ditem))) {
1064 		dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
1065 			     item_size, sizeof(*ditem));
1066 		return -EUCLEAN;
1067 	}
1068 
1069 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
1070 	if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
1071 		dev_item_err(leaf, slot,
1072 			     "devid mismatch: key has=%llu item has=%llu",
1073 			     key->offset, btrfs_device_id(leaf, ditem));
1074 		return -EUCLEAN;
1075 	}
1076 
1077 	/*
1078 	 * For device total_bytes, we don't have reliable way to check it, as
1079 	 * it can be 0 for device removal. Device size check can only be done
1080 	 * by dev extents check.
1081 	 */
1082 	if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1083 		     btrfs_device_total_bytes(leaf, ditem))) {
1084 		dev_item_err(leaf, slot,
1085 			     "invalid bytes used: have %llu expect [0, %llu]",
1086 			     btrfs_device_bytes_used(leaf, ditem),
1087 			     btrfs_device_total_bytes(leaf, ditem));
1088 		return -EUCLEAN;
1089 	}
1090 	/*
1091 	 * Remaining members like io_align/type/gen/dev_group aren't really
1092 	 * utilized.  Skip them to make later usage of them easier.
1093 	 */
1094 	return 0;
1095 }
1096 
check_inode_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1097 static int check_inode_item(struct extent_buffer *leaf,
1098 			    struct btrfs_key *key, int slot)
1099 {
1100 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1101 	struct btrfs_inode_item *iitem;
1102 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1103 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1104 	const u32 item_size = btrfs_item_size(leaf, slot);
1105 	u32 mode;
1106 	int ret;
1107 	u32 flags;
1108 	u32 ro_flags;
1109 
1110 	ret = check_inode_key(leaf, key, slot);
1111 	if (unlikely(ret < 0))
1112 		return ret;
1113 
1114 	if (unlikely(item_size != sizeof(*iitem))) {
1115 		generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1116 			    item_size, sizeof(*iitem));
1117 		return -EUCLEAN;
1118 	}
1119 
1120 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1121 
1122 	/* Here we use super block generation + 1 to handle log tree */
1123 	if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1124 		inode_item_err(leaf, slot,
1125 			"invalid inode generation: has %llu expect (0, %llu]",
1126 			       btrfs_inode_generation(leaf, iitem),
1127 			       super_gen + 1);
1128 		return -EUCLEAN;
1129 	}
1130 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1131 	if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1132 		inode_item_err(leaf, slot,
1133 			"invalid inode transid: has %llu expect [0, %llu]",
1134 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
1135 		return -EUCLEAN;
1136 	}
1137 
1138 	/*
1139 	 * For size and nbytes it's better not to be too strict, as for dir
1140 	 * item its size/nbytes can easily get wrong, but doesn't affect
1141 	 * anything in the fs. So here we skip the check.
1142 	 */
1143 	mode = btrfs_inode_mode(leaf, iitem);
1144 	if (unlikely(mode & ~valid_mask)) {
1145 		inode_item_err(leaf, slot,
1146 			       "unknown mode bit detected: 0x%x",
1147 			       mode & ~valid_mask);
1148 		return -EUCLEAN;
1149 	}
1150 
1151 	/*
1152 	 * S_IFMT is not bit mapped so we can't completely rely on
1153 	 * is_power_of_2/has_single_bit_set, but it can save us from checking
1154 	 * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1155 	 */
1156 	if (!has_single_bit_set(mode & S_IFMT)) {
1157 		if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1158 			inode_item_err(leaf, slot,
1159 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
1160 				       mode & S_IFMT);
1161 			return -EUCLEAN;
1162 		}
1163 	}
1164 	if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1165 		inode_item_err(leaf, slot,
1166 		       "invalid nlink: has %u expect no more than 1 for dir",
1167 			btrfs_inode_nlink(leaf, iitem));
1168 		return -EUCLEAN;
1169 	}
1170 	btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1171 	if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1172 		inode_item_err(leaf, slot,
1173 			       "unknown incompat flags detected: 0x%x", flags);
1174 		return -EUCLEAN;
1175 	}
1176 	if (unlikely(!sb_rdonly(fs_info->sb) &&
1177 		     (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1178 		inode_item_err(leaf, slot,
1179 			"unknown ro-compat flags detected on writeable mount: 0x%x",
1180 			ro_flags);
1181 		return -EUCLEAN;
1182 	}
1183 	return 0;
1184 }
1185 
check_root_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1186 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1187 			   int slot)
1188 {
1189 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1190 	struct btrfs_root_item ri = { 0 };
1191 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1192 				     BTRFS_ROOT_SUBVOL_DEAD;
1193 	int ret;
1194 
1195 	ret = check_root_key(leaf, key, slot);
1196 	if (unlikely(ret < 0))
1197 		return ret;
1198 
1199 	if (unlikely(btrfs_item_size(leaf, slot) != sizeof(ri) &&
1200 		     btrfs_item_size(leaf, slot) !=
1201 		     btrfs_legacy_root_item_size())) {
1202 		generic_err(leaf, slot,
1203 			    "invalid root item size, have %u expect %zu or %u",
1204 			    btrfs_item_size(leaf, slot), sizeof(ri),
1205 			    btrfs_legacy_root_item_size());
1206 		return -EUCLEAN;
1207 	}
1208 
1209 	/*
1210 	 * For legacy root item, the members starting at generation_v2 will be
1211 	 * all filled with 0.
1212 	 * And since we allow geneartion_v2 as 0, it will still pass the check.
1213 	 */
1214 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1215 			   btrfs_item_size(leaf, slot));
1216 
1217 	/* Generation related */
1218 	if (unlikely(btrfs_root_generation(&ri) >
1219 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1220 		generic_err(leaf, slot,
1221 			"invalid root generation, have %llu expect (0, %llu]",
1222 			    btrfs_root_generation(&ri),
1223 			    btrfs_super_generation(fs_info->super_copy) + 1);
1224 		return -EUCLEAN;
1225 	}
1226 	if (unlikely(btrfs_root_generation_v2(&ri) >
1227 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1228 		generic_err(leaf, slot,
1229 		"invalid root v2 generation, have %llu expect (0, %llu]",
1230 			    btrfs_root_generation_v2(&ri),
1231 			    btrfs_super_generation(fs_info->super_copy) + 1);
1232 		return -EUCLEAN;
1233 	}
1234 	if (unlikely(btrfs_root_last_snapshot(&ri) >
1235 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1236 		generic_err(leaf, slot,
1237 		"invalid root last_snapshot, have %llu expect (0, %llu]",
1238 			    btrfs_root_last_snapshot(&ri),
1239 			    btrfs_super_generation(fs_info->super_copy) + 1);
1240 		return -EUCLEAN;
1241 	}
1242 
1243 	/* Alignment and level check */
1244 	if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1245 		generic_err(leaf, slot,
1246 		"invalid root bytenr, have %llu expect to be aligned to %u",
1247 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
1248 		return -EUCLEAN;
1249 	}
1250 	if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1251 		generic_err(leaf, slot,
1252 			    "invalid root level, have %u expect [0, %u]",
1253 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1254 		return -EUCLEAN;
1255 	}
1256 	if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1257 		generic_err(leaf, slot,
1258 			    "invalid root level, have %u expect [0, %u]",
1259 			    btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1260 		return -EUCLEAN;
1261 	}
1262 
1263 	/* Flags check */
1264 	if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1265 		generic_err(leaf, slot,
1266 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
1267 			    btrfs_root_flags(&ri), valid_root_flags);
1268 		return -EUCLEAN;
1269 	}
1270 	return 0;
1271 }
1272 
1273 __printf(3,4)
1274 __cold
extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)1275 static void extent_err(const struct extent_buffer *eb, int slot,
1276 		       const char *fmt, ...)
1277 {
1278 	struct btrfs_key key;
1279 	struct va_format vaf;
1280 	va_list args;
1281 	u64 bytenr;
1282 	u64 len;
1283 
1284 	btrfs_item_key_to_cpu(eb, &key, slot);
1285 	bytenr = key.objectid;
1286 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
1287 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1288 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1289 		len = eb->fs_info->nodesize;
1290 	else
1291 		len = key.offset;
1292 	va_start(args, fmt);
1293 
1294 	vaf.fmt = fmt;
1295 	vaf.va = &args;
1296 
1297 	dump_page(folio_page(eb->folios[0], 0), "eb page dump");
1298 	btrfs_crit(eb->fs_info,
1299 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1300 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1301 		eb->start, slot, bytenr, len, &vaf);
1302 	va_end(args);
1303 }
1304 
is_valid_dref_root(u64 rootid)1305 static bool is_valid_dref_root(u64 rootid)
1306 {
1307 	/*
1308 	 * The following tree root objectids are allowed to have a data backref:
1309 	 * - subvolume trees
1310 	 * - data reloc tree
1311 	 * - tree root
1312 	 *   For v1 space cache
1313 	 */
1314 	return is_fstree(rootid) || rootid == BTRFS_DATA_RELOC_TREE_OBJECTID ||
1315 	       rootid == BTRFS_ROOT_TREE_OBJECTID;
1316 }
1317 
check_extent_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1318 static int check_extent_item(struct extent_buffer *leaf,
1319 			     struct btrfs_key *key, int slot,
1320 			     struct btrfs_key *prev_key)
1321 {
1322 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1323 	struct btrfs_extent_item *ei;
1324 	bool is_tree_block = false;
1325 	unsigned long ptr;	/* Current pointer inside inline refs */
1326 	unsigned long end;	/* Extent item end */
1327 	const u32 item_size = btrfs_item_size(leaf, slot);
1328 	u8 last_type = 0;
1329 	u64 last_seq = U64_MAX;
1330 	u64 flags;
1331 	u64 generation;
1332 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1333 	u64 inline_refs = 0;	/* found total inline refs */
1334 
1335 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1336 		     !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1337 		generic_err(leaf, slot,
1338 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1339 		return -EUCLEAN;
1340 	}
1341 	/* key->objectid is the bytenr for both key types */
1342 	if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1343 		generic_err(leaf, slot,
1344 		"invalid key objectid, have %llu expect to be aligned to %u",
1345 			   key->objectid, fs_info->sectorsize);
1346 		return -EUCLEAN;
1347 	}
1348 
1349 	/* key->offset is tree level for METADATA_ITEM_KEY */
1350 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1351 		     key->offset >= BTRFS_MAX_LEVEL)) {
1352 		extent_err(leaf, slot,
1353 			   "invalid tree level, have %llu expect [0, %u]",
1354 			   key->offset, BTRFS_MAX_LEVEL - 1);
1355 		return -EUCLEAN;
1356 	}
1357 
1358 	/*
1359 	 * EXTENT/METADATA_ITEM consists of:
1360 	 * 1) One btrfs_extent_item
1361 	 *    Records the total refs, type and generation of the extent.
1362 	 *
1363 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1364 	 *    Records the first key and level of the tree block.
1365 	 *
1366 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1367 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1368 	 *    2.1) The ref type, one of the 4
1369 	 *         TREE_BLOCK_REF	Tree block only
1370 	 *         SHARED_BLOCK_REF	Tree block only
1371 	 *         EXTENT_DATA_REF	Data only
1372 	 *         SHARED_DATA_REF	Data only
1373 	 *    2.2) Ref type specific data
1374 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1375 	 *         data structure.
1376 	 *
1377 	 *    All above inline items should follow the order:
1378 	 *
1379 	 *    - All btrfs_extent_inline_ref::type should be in an ascending
1380 	 *      order
1381 	 *
1382 	 *    - Within the same type, the items should follow a descending
1383 	 *      order by their sequence number. The sequence number is
1384 	 *      determined by:
1385 	 *      * btrfs_extent_inline_ref::offset for all types  other than
1386 	 *        EXTENT_DATA_REF
1387 	 *      * hash_extent_data_ref() for EXTENT_DATA_REF
1388 	 */
1389 	if (unlikely(item_size < sizeof(*ei))) {
1390 		extent_err(leaf, slot,
1391 			   "invalid item size, have %u expect [%zu, %u)",
1392 			   item_size, sizeof(*ei),
1393 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1394 		return -EUCLEAN;
1395 	}
1396 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1397 
1398 	/* Checks against extent_item */
1399 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1400 	flags = btrfs_extent_flags(leaf, ei);
1401 	total_refs = btrfs_extent_refs(leaf, ei);
1402 	generation = btrfs_extent_generation(leaf, ei);
1403 	if (unlikely(generation >
1404 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1405 		extent_err(leaf, slot,
1406 			   "invalid generation, have %llu expect (0, %llu]",
1407 			   generation,
1408 			   btrfs_super_generation(fs_info->super_copy) + 1);
1409 		return -EUCLEAN;
1410 	}
1411 	if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1412 						  BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1413 		extent_err(leaf, slot,
1414 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1415 			flags, BTRFS_EXTENT_FLAG_DATA |
1416 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1417 		return -EUCLEAN;
1418 	}
1419 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1420 	if (is_tree_block) {
1421 		if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1422 			     key->offset != fs_info->nodesize)) {
1423 			extent_err(leaf, slot,
1424 				   "invalid extent length, have %llu expect %u",
1425 				   key->offset, fs_info->nodesize);
1426 			return -EUCLEAN;
1427 		}
1428 	} else {
1429 		if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1430 			extent_err(leaf, slot,
1431 			"invalid key type, have %u expect %u for data backref",
1432 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1433 			return -EUCLEAN;
1434 		}
1435 		if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1436 			extent_err(leaf, slot,
1437 			"invalid extent length, have %llu expect aligned to %u",
1438 				   key->offset, fs_info->sectorsize);
1439 			return -EUCLEAN;
1440 		}
1441 		if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1442 			extent_err(leaf, slot,
1443 			"invalid extent flag, data has full backref set");
1444 			return -EUCLEAN;
1445 		}
1446 	}
1447 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1448 
1449 	/* Check the special case of btrfs_tree_block_info */
1450 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1451 		struct btrfs_tree_block_info *info;
1452 
1453 		info = (struct btrfs_tree_block_info *)ptr;
1454 		if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1455 			extent_err(leaf, slot,
1456 			"invalid tree block info level, have %u expect [0, %u]",
1457 				   btrfs_tree_block_level(leaf, info),
1458 				   BTRFS_MAX_LEVEL - 1);
1459 			return -EUCLEAN;
1460 		}
1461 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1462 	}
1463 
1464 	/* Check inline refs */
1465 	while (ptr < end) {
1466 		struct btrfs_extent_inline_ref *iref;
1467 		struct btrfs_extent_data_ref *dref;
1468 		struct btrfs_shared_data_ref *sref;
1469 		u64 seq;
1470 		u64 dref_root;
1471 		u64 dref_objectid;
1472 		u64 dref_offset;
1473 		u64 inline_offset;
1474 		u8 inline_type;
1475 
1476 		if (unlikely(ptr + sizeof(*iref) > end)) {
1477 			extent_err(leaf, slot,
1478 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1479 				   ptr, sizeof(*iref), end);
1480 			return -EUCLEAN;
1481 		}
1482 		iref = (struct btrfs_extent_inline_ref *)ptr;
1483 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1484 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1485 		seq = inline_offset;
1486 		if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1487 			extent_err(leaf, slot,
1488 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1489 				   ptr, btrfs_extent_inline_ref_size(inline_type), end);
1490 			return -EUCLEAN;
1491 		}
1492 
1493 		switch (inline_type) {
1494 		/* inline_offset is subvolid of the owner, no need to check */
1495 		case BTRFS_TREE_BLOCK_REF_KEY:
1496 			inline_refs++;
1497 			break;
1498 		/* Contains parent bytenr */
1499 		case BTRFS_SHARED_BLOCK_REF_KEY:
1500 			if (unlikely(!IS_ALIGNED(inline_offset,
1501 						 fs_info->sectorsize))) {
1502 				extent_err(leaf, slot,
1503 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1504 					   inline_offset, fs_info->sectorsize);
1505 				return -EUCLEAN;
1506 			}
1507 			inline_refs++;
1508 			break;
1509 		/*
1510 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1511 		 * The only obvious corruption can happen in that offset.
1512 		 */
1513 		case BTRFS_EXTENT_DATA_REF_KEY:
1514 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1515 			dref_root = btrfs_extent_data_ref_root(leaf, dref);
1516 			dref_objectid = btrfs_extent_data_ref_objectid(leaf, dref);
1517 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1518 			seq = hash_extent_data_ref(
1519 					btrfs_extent_data_ref_root(leaf, dref),
1520 					btrfs_extent_data_ref_objectid(leaf, dref),
1521 					btrfs_extent_data_ref_offset(leaf, dref));
1522 			if (unlikely(!is_valid_dref_root(dref_root))) {
1523 				extent_err(leaf, slot,
1524 					   "invalid data ref root value %llu",
1525 					   dref_root);
1526 				return -EUCLEAN;
1527 			}
1528 			if (unlikely(dref_objectid < BTRFS_FIRST_FREE_OBJECTID ||
1529 				     dref_objectid > BTRFS_LAST_FREE_OBJECTID)) {
1530 				extent_err(leaf, slot,
1531 					   "invalid data ref objectid value %llu",
1532 					   dref_objectid);
1533 				return -EUCLEAN;
1534 			}
1535 			if (unlikely(!IS_ALIGNED(dref_offset,
1536 						 fs_info->sectorsize))) {
1537 				extent_err(leaf, slot,
1538 		"invalid data ref offset, have %llu expect aligned to %u",
1539 					   dref_offset, fs_info->sectorsize);
1540 				return -EUCLEAN;
1541 			}
1542 			if (unlikely(btrfs_extent_data_ref_count(leaf, dref) == 0)) {
1543 				extent_err(leaf, slot,
1544 			"invalid data ref count, should have non-zero value");
1545 				return -EUCLEAN;
1546 			}
1547 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1548 			break;
1549 		/* Contains parent bytenr and ref count */
1550 		case BTRFS_SHARED_DATA_REF_KEY:
1551 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1552 			if (unlikely(!IS_ALIGNED(inline_offset,
1553 						 fs_info->sectorsize))) {
1554 				extent_err(leaf, slot,
1555 		"invalid data parent bytenr, have %llu expect aligned to %u",
1556 					   inline_offset, fs_info->sectorsize);
1557 				return -EUCLEAN;
1558 			}
1559 			if (unlikely(btrfs_shared_data_ref_count(leaf, sref) == 0)) {
1560 				extent_err(leaf, slot,
1561 			"invalid shared data ref count, should have non-zero value");
1562 				return -EUCLEAN;
1563 			}
1564 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1565 			break;
1566 		case BTRFS_EXTENT_OWNER_REF_KEY:
1567 			WARN_ON(!btrfs_fs_incompat(fs_info, SIMPLE_QUOTA));
1568 			break;
1569 		default:
1570 			extent_err(leaf, slot, "unknown inline ref type: %u",
1571 				   inline_type);
1572 			return -EUCLEAN;
1573 		}
1574 		if (inline_type < last_type) {
1575 			extent_err(leaf, slot,
1576 				   "inline ref out-of-order: has type %u, prev type %u",
1577 				   inline_type, last_type);
1578 			return -EUCLEAN;
1579 		}
1580 		/* Type changed, allow the sequence starts from U64_MAX again. */
1581 		if (inline_type > last_type)
1582 			last_seq = U64_MAX;
1583 		if (seq > last_seq) {
1584 			extent_err(leaf, slot,
1585 "inline ref out-of-order: has type %u offset %llu seq 0x%llx, prev type %u seq 0x%llx",
1586 				   inline_type, inline_offset, seq,
1587 				   last_type, last_seq);
1588 			return -EUCLEAN;
1589 		}
1590 		last_type = inline_type;
1591 		last_seq = seq;
1592 		ptr += btrfs_extent_inline_ref_size(inline_type);
1593 	}
1594 	/* No padding is allowed */
1595 	if (unlikely(ptr != end)) {
1596 		extent_err(leaf, slot,
1597 			   "invalid extent item size, padding bytes found");
1598 		return -EUCLEAN;
1599 	}
1600 
1601 	/* Finally, check the inline refs against total refs */
1602 	if (unlikely(inline_refs > total_refs)) {
1603 		extent_err(leaf, slot,
1604 			"invalid extent refs, have %llu expect >= inline %llu",
1605 			   total_refs, inline_refs);
1606 		return -EUCLEAN;
1607 	}
1608 
1609 	if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1610 	    (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1611 		u64 prev_end = prev_key->objectid;
1612 
1613 		if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1614 			prev_end += fs_info->nodesize;
1615 		else
1616 			prev_end += prev_key->offset;
1617 
1618 		if (unlikely(prev_end > key->objectid)) {
1619 			extent_err(leaf, slot,
1620 	"previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1621 				   prev_key->objectid, prev_key->type,
1622 				   prev_key->offset, key->objectid, key->type,
1623 				   key->offset);
1624 			return -EUCLEAN;
1625 		}
1626 	}
1627 
1628 	return 0;
1629 }
1630 
check_simple_keyed_refs(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1631 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1632 				   struct btrfs_key *key, int slot)
1633 {
1634 	u32 expect_item_size = 0;
1635 
1636 	if (key->type == BTRFS_SHARED_DATA_REF_KEY) {
1637 		struct btrfs_shared_data_ref *sref;
1638 
1639 		sref = btrfs_item_ptr(leaf, slot, struct btrfs_shared_data_ref);
1640 		if (unlikely(btrfs_shared_data_ref_count(leaf, sref) == 0)) {
1641 			extent_err(leaf, slot,
1642 		"invalid shared data backref count, should have non-zero value");
1643 			return -EUCLEAN;
1644 		}
1645 
1646 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1647 	}
1648 
1649 	if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
1650 		generic_err(leaf, slot,
1651 		"invalid item size, have %u expect %u for key type %u",
1652 			    btrfs_item_size(leaf, slot),
1653 			    expect_item_size, key->type);
1654 		return -EUCLEAN;
1655 	}
1656 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1657 		generic_err(leaf, slot,
1658 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1659 			    key->objectid, leaf->fs_info->sectorsize);
1660 		return -EUCLEAN;
1661 	}
1662 	if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1663 		     !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1664 		extent_err(leaf, slot,
1665 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1666 			   key->offset, leaf->fs_info->sectorsize);
1667 		return -EUCLEAN;
1668 	}
1669 	return 0;
1670 }
1671 
check_extent_data_ref(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1672 static int check_extent_data_ref(struct extent_buffer *leaf,
1673 				 struct btrfs_key *key, int slot)
1674 {
1675 	struct btrfs_extent_data_ref *dref;
1676 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1677 	const unsigned long end = ptr + btrfs_item_size(leaf, slot);
1678 
1679 	if (unlikely(btrfs_item_size(leaf, slot) % sizeof(*dref) != 0)) {
1680 		generic_err(leaf, slot,
1681 	"invalid item size, have %u expect aligned to %zu for key type %u",
1682 			    btrfs_item_size(leaf, slot),
1683 			    sizeof(*dref), key->type);
1684 		return -EUCLEAN;
1685 	}
1686 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1687 		generic_err(leaf, slot,
1688 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1689 			    key->objectid, leaf->fs_info->sectorsize);
1690 		return -EUCLEAN;
1691 	}
1692 	for (; ptr < end; ptr += sizeof(*dref)) {
1693 		u64 root;
1694 		u64 objectid;
1695 		u64 offset;
1696 
1697 		/*
1698 		 * We cannot check the extent_data_ref hash due to possible
1699 		 * overflow from the leaf due to hash collisions.
1700 		 */
1701 		dref = (struct btrfs_extent_data_ref *)ptr;
1702 		root = btrfs_extent_data_ref_root(leaf, dref);
1703 		objectid = btrfs_extent_data_ref_objectid(leaf, dref);
1704 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1705 		if (unlikely(!is_valid_dref_root(root))) {
1706 			extent_err(leaf, slot,
1707 				   "invalid extent data backref root value %llu",
1708 				   root);
1709 			return -EUCLEAN;
1710 		}
1711 		if (unlikely(objectid < BTRFS_FIRST_FREE_OBJECTID ||
1712 			     objectid > BTRFS_LAST_FREE_OBJECTID)) {
1713 			extent_err(leaf, slot,
1714 				   "invalid extent data backref objectid value %llu",
1715 				   root);
1716 			return -EUCLEAN;
1717 		}
1718 		if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1719 			extent_err(leaf, slot,
1720 	"invalid extent data backref offset, have %llu expect aligned to %u",
1721 				   offset, leaf->fs_info->sectorsize);
1722 			return -EUCLEAN;
1723 		}
1724 		if (unlikely(btrfs_extent_data_ref_count(leaf, dref) == 0)) {
1725 			extent_err(leaf, slot,
1726 	"invalid extent data backref count, should have non-zero value");
1727 			return -EUCLEAN;
1728 		}
1729 	}
1730 	return 0;
1731 }
1732 
1733 #define inode_ref_err(eb, slot, fmt, args...)			\
1734 	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)1735 static int check_inode_ref(struct extent_buffer *leaf,
1736 			   struct btrfs_key *key, struct btrfs_key *prev_key,
1737 			   int slot)
1738 {
1739 	struct btrfs_inode_ref *iref;
1740 	unsigned long ptr;
1741 	unsigned long end;
1742 
1743 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1744 		return -EUCLEAN;
1745 	/* namelen can't be 0, so item_size == sizeof() is also invalid */
1746 	if (unlikely(btrfs_item_size(leaf, slot) <= sizeof(*iref))) {
1747 		inode_ref_err(leaf, slot,
1748 			"invalid item size, have %u expect (%zu, %u)",
1749 			btrfs_item_size(leaf, slot),
1750 			sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1751 		return -EUCLEAN;
1752 	}
1753 
1754 	ptr = btrfs_item_ptr_offset(leaf, slot);
1755 	end = ptr + btrfs_item_size(leaf, slot);
1756 	while (ptr < end) {
1757 		u16 namelen;
1758 
1759 		if (unlikely(ptr + sizeof(iref) > end)) {
1760 			inode_ref_err(leaf, slot,
1761 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1762 				ptr, end, sizeof(iref));
1763 			return -EUCLEAN;
1764 		}
1765 
1766 		iref = (struct btrfs_inode_ref *)ptr;
1767 		namelen = btrfs_inode_ref_name_len(leaf, iref);
1768 		if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1769 			inode_ref_err(leaf, slot,
1770 				"inode ref overflow, ptr %lu end %lu namelen %u",
1771 				ptr, end, namelen);
1772 			return -EUCLEAN;
1773 		}
1774 
1775 		/*
1776 		 * NOTE: In theory we should record all found index numbers
1777 		 * to find any duplicated indexes, but that will be too time
1778 		 * consuming for inodes with too many hard links.
1779 		 */
1780 		ptr += sizeof(*iref) + namelen;
1781 	}
1782 	return 0;
1783 }
1784 
check_raid_stripe_extent(const struct extent_buffer * leaf,const struct btrfs_key * key,int slot)1785 static int check_raid_stripe_extent(const struct extent_buffer *leaf,
1786 				    const struct btrfs_key *key, int slot)
1787 {
1788 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1789 		generic_err(leaf, slot,
1790 "invalid key objectid for raid stripe extent, have %llu expect aligned to %u",
1791 			    key->objectid, leaf->fs_info->sectorsize);
1792 		return -EUCLEAN;
1793 	}
1794 
1795 	if (unlikely(!btrfs_fs_incompat(leaf->fs_info, RAID_STRIPE_TREE))) {
1796 		generic_err(leaf, slot,
1797 	"RAID_STRIPE_EXTENT present but RAID_STRIPE_TREE incompat bit unset");
1798 		return -EUCLEAN;
1799 	}
1800 
1801 	return 0;
1802 }
1803 
check_dev_extent_item(const struct extent_buffer * leaf,const struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1804 static int check_dev_extent_item(const struct extent_buffer *leaf,
1805 				 const struct btrfs_key *key,
1806 				 int slot,
1807 				 struct btrfs_key *prev_key)
1808 {
1809 	struct btrfs_dev_extent *de;
1810 	const u32 sectorsize = leaf->fs_info->sectorsize;
1811 
1812 	de = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
1813 	/* Basic fixed member checks. */
1814 	if (unlikely(btrfs_dev_extent_chunk_tree(leaf, de) !=
1815 		     BTRFS_CHUNK_TREE_OBJECTID)) {
1816 		generic_err(leaf, slot,
1817 			    "invalid dev extent chunk tree id, has %llu expect %llu",
1818 			    btrfs_dev_extent_chunk_tree(leaf, de),
1819 			    BTRFS_CHUNK_TREE_OBJECTID);
1820 		return -EUCLEAN;
1821 	}
1822 	if (unlikely(btrfs_dev_extent_chunk_objectid(leaf, de) !=
1823 		     BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
1824 		generic_err(leaf, slot,
1825 			    "invalid dev extent chunk objectid, has %llu expect %llu",
1826 			    btrfs_dev_extent_chunk_objectid(leaf, de),
1827 			    BTRFS_FIRST_CHUNK_TREE_OBJECTID);
1828 		return -EUCLEAN;
1829 	}
1830 	/* Alignment check. */
1831 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
1832 		generic_err(leaf, slot,
1833 			    "invalid dev extent key.offset, has %llu not aligned to %u",
1834 			    key->offset, sectorsize);
1835 		return -EUCLEAN;
1836 	}
1837 	if (unlikely(!IS_ALIGNED(btrfs_dev_extent_chunk_offset(leaf, de),
1838 				 sectorsize))) {
1839 		generic_err(leaf, slot,
1840 			    "invalid dev extent chunk offset, has %llu not aligned to %u",
1841 			    btrfs_dev_extent_chunk_objectid(leaf, de),
1842 			    sectorsize);
1843 		return -EUCLEAN;
1844 	}
1845 	if (unlikely(!IS_ALIGNED(btrfs_dev_extent_length(leaf, de),
1846 				 sectorsize))) {
1847 		generic_err(leaf, slot,
1848 			    "invalid dev extent length, has %llu not aligned to %u",
1849 			    btrfs_dev_extent_length(leaf, de), sectorsize);
1850 		return -EUCLEAN;
1851 	}
1852 	/* Overlap check with previous dev extent. */
1853 	if (slot && prev_key->objectid == key->objectid &&
1854 	    prev_key->type == key->type) {
1855 		struct btrfs_dev_extent *prev_de;
1856 		u64 prev_len;
1857 
1858 		prev_de = btrfs_item_ptr(leaf, slot - 1, struct btrfs_dev_extent);
1859 		prev_len = btrfs_dev_extent_length(leaf, prev_de);
1860 		if (unlikely(prev_key->offset + prev_len > key->offset)) {
1861 			generic_err(leaf, slot,
1862 		"dev extent overlap, prev offset %llu len %llu current offset %llu",
1863 				    prev_key->objectid, prev_len, key->offset);
1864 			return -EUCLEAN;
1865 		}
1866 	}
1867 	return 0;
1868 }
1869 
1870 /*
1871  * Common point to switch the item-specific validation.
1872  */
check_leaf_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1873 static enum btrfs_tree_block_status check_leaf_item(struct extent_buffer *leaf,
1874 						    struct btrfs_key *key,
1875 						    int slot,
1876 						    struct btrfs_key *prev_key)
1877 {
1878 	int ret = 0;
1879 	struct btrfs_chunk *chunk;
1880 
1881 	switch (key->type) {
1882 	case BTRFS_EXTENT_DATA_KEY:
1883 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1884 		break;
1885 	case BTRFS_EXTENT_CSUM_KEY:
1886 		ret = check_csum_item(leaf, key, slot, prev_key);
1887 		break;
1888 	case BTRFS_DIR_ITEM_KEY:
1889 	case BTRFS_DIR_INDEX_KEY:
1890 	case BTRFS_XATTR_ITEM_KEY:
1891 		ret = check_dir_item(leaf, key, prev_key, slot);
1892 		break;
1893 	case BTRFS_INODE_REF_KEY:
1894 		ret = check_inode_ref(leaf, key, prev_key, slot);
1895 		break;
1896 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1897 		ret = check_block_group_item(leaf, key, slot);
1898 		break;
1899 	case BTRFS_CHUNK_ITEM_KEY:
1900 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1901 		ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1902 		break;
1903 	case BTRFS_DEV_ITEM_KEY:
1904 		ret = check_dev_item(leaf, key, slot);
1905 		break;
1906 	case BTRFS_DEV_EXTENT_KEY:
1907 		ret = check_dev_extent_item(leaf, key, slot, prev_key);
1908 		break;
1909 	case BTRFS_INODE_ITEM_KEY:
1910 		ret = check_inode_item(leaf, key, slot);
1911 		break;
1912 	case BTRFS_ROOT_ITEM_KEY:
1913 		ret = check_root_item(leaf, key, slot);
1914 		break;
1915 	case BTRFS_EXTENT_ITEM_KEY:
1916 	case BTRFS_METADATA_ITEM_KEY:
1917 		ret = check_extent_item(leaf, key, slot, prev_key);
1918 		break;
1919 	case BTRFS_TREE_BLOCK_REF_KEY:
1920 	case BTRFS_SHARED_DATA_REF_KEY:
1921 	case BTRFS_SHARED_BLOCK_REF_KEY:
1922 		ret = check_simple_keyed_refs(leaf, key, slot);
1923 		break;
1924 	case BTRFS_EXTENT_DATA_REF_KEY:
1925 		ret = check_extent_data_ref(leaf, key, slot);
1926 		break;
1927 	case BTRFS_RAID_STRIPE_KEY:
1928 		ret = check_raid_stripe_extent(leaf, key, slot);
1929 		break;
1930 	}
1931 
1932 	if (ret)
1933 		return BTRFS_TREE_BLOCK_INVALID_ITEM;
1934 	return BTRFS_TREE_BLOCK_CLEAN;
1935 }
1936 
__btrfs_check_leaf(struct extent_buffer * leaf)1937 enum btrfs_tree_block_status __btrfs_check_leaf(struct extent_buffer *leaf)
1938 {
1939 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1940 	/* No valid key type is 0, so all key should be larger than this key */
1941 	struct btrfs_key prev_key = {0, 0, 0};
1942 	struct btrfs_key key;
1943 	u32 nritems = btrfs_header_nritems(leaf);
1944 	int slot;
1945 
1946 	if (unlikely(btrfs_header_level(leaf) != 0)) {
1947 		generic_err(leaf, 0,
1948 			"invalid level for leaf, have %d expect 0",
1949 			btrfs_header_level(leaf));
1950 		return BTRFS_TREE_BLOCK_INVALID_LEVEL;
1951 	}
1952 
1953 	if (unlikely(!btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_WRITTEN))) {
1954 		generic_err(leaf, 0, "invalid flag for leaf, WRITTEN not set");
1955 		return BTRFS_TREE_BLOCK_WRITTEN_NOT_SET;
1956 	}
1957 
1958 	/*
1959 	 * Extent buffers from a relocation tree have a owner field that
1960 	 * corresponds to the subvolume tree they are based on. So just from an
1961 	 * extent buffer alone we can not find out what is the id of the
1962 	 * corresponding subvolume tree, so we can not figure out if the extent
1963 	 * buffer corresponds to the root of the relocation tree or not. So
1964 	 * skip this check for relocation trees.
1965 	 */
1966 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1967 		u64 owner = btrfs_header_owner(leaf);
1968 
1969 		/* These trees must never be empty */
1970 		if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1971 			     owner == BTRFS_CHUNK_TREE_OBJECTID ||
1972 			     owner == BTRFS_DEV_TREE_OBJECTID ||
1973 			     owner == BTRFS_FS_TREE_OBJECTID ||
1974 			     owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1975 			generic_err(leaf, 0,
1976 			"invalid root, root %llu must never be empty",
1977 				    owner);
1978 			return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1979 		}
1980 
1981 		/* Unknown tree */
1982 		if (unlikely(owner == 0)) {
1983 			generic_err(leaf, 0,
1984 				"invalid owner, root 0 is not defined");
1985 			return BTRFS_TREE_BLOCK_INVALID_OWNER;
1986 		}
1987 
1988 		/* EXTENT_TREE_V2 can have empty extent trees. */
1989 		if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1990 			return BTRFS_TREE_BLOCK_CLEAN;
1991 
1992 		if (unlikely(owner == BTRFS_EXTENT_TREE_OBJECTID)) {
1993 			generic_err(leaf, 0,
1994 			"invalid root, root %llu must never be empty",
1995 				    owner);
1996 			return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
1997 		}
1998 
1999 		return BTRFS_TREE_BLOCK_CLEAN;
2000 	}
2001 
2002 	if (unlikely(nritems == 0))
2003 		return BTRFS_TREE_BLOCK_CLEAN;
2004 
2005 	/*
2006 	 * Check the following things to make sure this is a good leaf, and
2007 	 * leaf users won't need to bother with similar sanity checks:
2008 	 *
2009 	 * 1) key ordering
2010 	 * 2) item offset and size
2011 	 *    No overlap, no hole, all inside the leaf.
2012 	 * 3) item content
2013 	 *    If possible, do comprehensive sanity check.
2014 	 *    NOTE: All checks must only rely on the item data itself.
2015 	 */
2016 	for (slot = 0; slot < nritems; slot++) {
2017 		u32 item_end_expected;
2018 		u64 item_data_end;
2019 		enum btrfs_tree_block_status ret;
2020 
2021 		btrfs_item_key_to_cpu(leaf, &key, slot);
2022 
2023 		/* Make sure the keys are in the right order */
2024 		if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
2025 			generic_err(leaf, slot,
2026 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
2027 				prev_key.objectid, prev_key.type,
2028 				prev_key.offset, key.objectid, key.type,
2029 				key.offset);
2030 			return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
2031 		}
2032 
2033 		item_data_end = (u64)btrfs_item_offset(leaf, slot) +
2034 				btrfs_item_size(leaf, slot);
2035 		/*
2036 		 * Make sure the offset and ends are right, remember that the
2037 		 * item data starts at the end of the leaf and grows towards the
2038 		 * front.
2039 		 */
2040 		if (slot == 0)
2041 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
2042 		else
2043 			item_end_expected = btrfs_item_offset(leaf,
2044 								 slot - 1);
2045 		if (unlikely(item_data_end != item_end_expected)) {
2046 			generic_err(leaf, slot,
2047 				"unexpected item end, have %llu expect %u",
2048 				item_data_end, item_end_expected);
2049 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
2050 		}
2051 
2052 		/*
2053 		 * Check to make sure that we don't point outside of the leaf,
2054 		 * just in case all the items are consistent to each other, but
2055 		 * all point outside of the leaf.
2056 		 */
2057 		if (unlikely(item_data_end > BTRFS_LEAF_DATA_SIZE(fs_info))) {
2058 			generic_err(leaf, slot,
2059 			"slot end outside of leaf, have %llu expect range [0, %u]",
2060 				item_data_end, BTRFS_LEAF_DATA_SIZE(fs_info));
2061 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
2062 		}
2063 
2064 		/* Also check if the item pointer overlaps with btrfs item. */
2065 		if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
2066 			     btrfs_item_nr_offset(leaf, slot) + sizeof(struct btrfs_item))) {
2067 			generic_err(leaf, slot,
2068 		"slot overlaps with its data, item end %lu data start %lu",
2069 				btrfs_item_nr_offset(leaf, slot) +
2070 				sizeof(struct btrfs_item),
2071 				btrfs_item_ptr_offset(leaf, slot));
2072 			return BTRFS_TREE_BLOCK_INVALID_OFFSETS;
2073 		}
2074 
2075 		/* Check if the item size and content meet other criteria. */
2076 		ret = check_leaf_item(leaf, &key, slot, &prev_key);
2077 		if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
2078 			return ret;
2079 
2080 		prev_key.objectid = key.objectid;
2081 		prev_key.type = key.type;
2082 		prev_key.offset = key.offset;
2083 	}
2084 
2085 	return BTRFS_TREE_BLOCK_CLEAN;
2086 }
2087 
btrfs_check_leaf(struct extent_buffer * leaf)2088 int btrfs_check_leaf(struct extent_buffer *leaf)
2089 {
2090 	enum btrfs_tree_block_status ret;
2091 
2092 	ret = __btrfs_check_leaf(leaf);
2093 	if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
2094 		return -EUCLEAN;
2095 	return 0;
2096 }
2097 ALLOW_ERROR_INJECTION(btrfs_check_leaf, ERRNO);
2098 
__btrfs_check_node(struct extent_buffer * node)2099 enum btrfs_tree_block_status __btrfs_check_node(struct extent_buffer *node)
2100 {
2101 	struct btrfs_fs_info *fs_info = node->fs_info;
2102 	unsigned long nr = btrfs_header_nritems(node);
2103 	struct btrfs_key key, next_key;
2104 	int slot;
2105 	int level = btrfs_header_level(node);
2106 	u64 bytenr;
2107 
2108 	if (unlikely(!btrfs_header_flag(node, BTRFS_HEADER_FLAG_WRITTEN))) {
2109 		generic_err(node, 0, "invalid flag for node, WRITTEN not set");
2110 		return BTRFS_TREE_BLOCK_WRITTEN_NOT_SET;
2111 	}
2112 
2113 	if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
2114 		generic_err(node, 0,
2115 			"invalid level for node, have %d expect [1, %d]",
2116 			level, BTRFS_MAX_LEVEL - 1);
2117 		return BTRFS_TREE_BLOCK_INVALID_LEVEL;
2118 	}
2119 	if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
2120 		btrfs_crit(fs_info,
2121 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
2122 			   btrfs_header_owner(node), node->start,
2123 			   nr == 0 ? "small" : "large", nr,
2124 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
2125 		return BTRFS_TREE_BLOCK_INVALID_NRITEMS;
2126 	}
2127 
2128 	for (slot = 0; slot < nr - 1; slot++) {
2129 		bytenr = btrfs_node_blockptr(node, slot);
2130 		btrfs_node_key_to_cpu(node, &key, slot);
2131 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
2132 
2133 		if (unlikely(!bytenr)) {
2134 			generic_err(node, slot,
2135 				"invalid NULL node pointer");
2136 			return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
2137 		}
2138 		if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
2139 			generic_err(node, slot,
2140 			"unaligned pointer, have %llu should be aligned to %u",
2141 				bytenr, fs_info->sectorsize);
2142 			return BTRFS_TREE_BLOCK_INVALID_BLOCKPTR;
2143 		}
2144 
2145 		if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
2146 			generic_err(node, slot,
2147 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
2148 				key.objectid, key.type, key.offset,
2149 				next_key.objectid, next_key.type,
2150 				next_key.offset);
2151 			return BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
2152 		}
2153 	}
2154 	return BTRFS_TREE_BLOCK_CLEAN;
2155 }
2156 
btrfs_check_node(struct extent_buffer * node)2157 int btrfs_check_node(struct extent_buffer *node)
2158 {
2159 	enum btrfs_tree_block_status ret;
2160 
2161 	ret = __btrfs_check_node(node);
2162 	if (unlikely(ret != BTRFS_TREE_BLOCK_CLEAN))
2163 		return -EUCLEAN;
2164 	return 0;
2165 }
2166 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
2167 
btrfs_check_eb_owner(const struct extent_buffer * eb,u64 root_owner)2168 int btrfs_check_eb_owner(const struct extent_buffer *eb, u64 root_owner)
2169 {
2170 	const bool is_subvol = is_fstree(root_owner);
2171 	const u64 eb_owner = btrfs_header_owner(eb);
2172 
2173 	/*
2174 	 * Skip dummy fs, as selftests don't create unique ebs for each dummy
2175 	 * root.
2176 	 */
2177 	if (btrfs_is_testing(eb->fs_info))
2178 		return 0;
2179 	/*
2180 	 * There are several call sites (backref walking, qgroup, and data
2181 	 * reloc) passing 0 as @root_owner, as they are not holding the
2182 	 * tree root.  In that case, we can not do a reliable ownership check,
2183 	 * so just exit.
2184 	 */
2185 	if (root_owner == 0)
2186 		return 0;
2187 	/*
2188 	 * These trees use key.offset as their owner, our callers don't have
2189 	 * the extra capacity to pass key.offset here.  So we just skip them.
2190 	 */
2191 	if (root_owner == BTRFS_TREE_LOG_OBJECTID ||
2192 	    root_owner == BTRFS_TREE_RELOC_OBJECTID)
2193 		return 0;
2194 
2195 	if (!is_subvol) {
2196 		/* For non-subvolume trees, the eb owner should match root owner */
2197 		if (unlikely(root_owner != eb_owner)) {
2198 			btrfs_crit(eb->fs_info,
2199 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect %llu",
2200 				btrfs_header_level(eb) == 0 ? "leaf" : "node",
2201 				root_owner, btrfs_header_bytenr(eb), eb_owner,
2202 				root_owner);
2203 			return -EUCLEAN;
2204 		}
2205 		return 0;
2206 	}
2207 
2208 	/*
2209 	 * For subvolume trees, owners can mismatch, but they should all belong
2210 	 * to subvolume trees.
2211 	 */
2212 	if (unlikely(is_subvol != is_fstree(eb_owner))) {
2213 		btrfs_crit(eb->fs_info,
2214 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect [%llu, %llu]",
2215 			btrfs_header_level(eb) == 0 ? "leaf" : "node",
2216 			root_owner, btrfs_header_bytenr(eb), eb_owner,
2217 			BTRFS_FIRST_FREE_OBJECTID, BTRFS_LAST_FREE_OBJECTID);
2218 		return -EUCLEAN;
2219 	}
2220 	return 0;
2221 }
2222 
btrfs_verify_level_key(struct extent_buffer * eb,const struct btrfs_tree_parent_check * check)2223 int btrfs_verify_level_key(struct extent_buffer *eb,
2224 			   const struct btrfs_tree_parent_check *check)
2225 {
2226 	struct btrfs_fs_info *fs_info = eb->fs_info;
2227 	int found_level;
2228 	struct btrfs_key found_key;
2229 	int ret;
2230 
2231 	found_level = btrfs_header_level(eb);
2232 	if (found_level != check->level) {
2233 		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2234 		     KERN_ERR "BTRFS: tree level check failed\n");
2235 		btrfs_err(fs_info,
2236 "tree level mismatch detected, bytenr=%llu level expected=%u has=%u",
2237 			  eb->start, check->level, found_level);
2238 		return -EIO;
2239 	}
2240 
2241 	if (!check->has_first_key)
2242 		return 0;
2243 
2244 	/*
2245 	 * For live tree block (new tree blocks in current transaction),
2246 	 * we need proper lock context to avoid race, which is impossible here.
2247 	 * So we only checks tree blocks which is read from disk, whose
2248 	 * generation <= fs_info->last_trans_committed.
2249 	 */
2250 	if (btrfs_header_generation(eb) > btrfs_get_last_trans_committed(fs_info))
2251 		return 0;
2252 
2253 	/* We have @first_key, so this @eb must have at least one item */
2254 	if (btrfs_header_nritems(eb) == 0) {
2255 		btrfs_err(fs_info,
2256 		"invalid tree nritems, bytenr=%llu nritems=0 expect >0",
2257 			  eb->start);
2258 		WARN_ON(IS_ENABLED(CONFIG_BTRFS_DEBUG));
2259 		return -EUCLEAN;
2260 	}
2261 
2262 	if (found_level)
2263 		btrfs_node_key_to_cpu(eb, &found_key, 0);
2264 	else
2265 		btrfs_item_key_to_cpu(eb, &found_key, 0);
2266 	ret = btrfs_comp_cpu_keys(&check->first_key, &found_key);
2267 
2268 	if (ret) {
2269 		WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
2270 		     KERN_ERR "BTRFS: tree first key check failed\n");
2271 		btrfs_err(fs_info,
2272 "tree first key mismatch detected, bytenr=%llu parent_transid=%llu key expected=(%llu,%u,%llu) has=(%llu,%u,%llu)",
2273 			  eb->start, check->transid, check->first_key.objectid,
2274 			  check->first_key.type, check->first_key.offset,
2275 			  found_key.objectid, found_key.type,
2276 			  found_key.offset);
2277 	}
2278 	return ret;
2279 }
2280