• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) Qu Wenruo 2017.  All rights reserved.
4  */
5 
6 /*
7  * The module is used to catch unexpected/corrupted tree block data.
8  * Such behavior can be caused either by a fuzzed image or bugs.
9  *
10  * The objective is to do leaf/node validation checks when tree block is read
11  * from disk, and check *every* possible member, so other code won't
12  * need to checking them again.
13  *
14  * Due to the potential and unwanted damage, every checker needs to be
15  * carefully reviewed otherwise so it does not prevent mount of valid images.
16  */
17 
18 #include <linux/types.h>
19 #include <linux/stddef.h>
20 #include <linux/error-injection.h>
21 #include "ctree.h"
22 #include "tree-checker.h"
23 #include "disk-io.h"
24 #include "compression.h"
25 #include "volumes.h"
26 #include "misc.h"
27 #include "btrfs_inode.h"
28 
29 /*
30  * Error message should follow the following format:
31  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
32  *
33  * @type:	leaf or node
34  * @identifier:	the necessary info to locate the leaf/node.
35  * 		It's recommended to decode key.objecitd/offset if it's
36  * 		meaningful.
37  * @reason:	describe the error
38  * @bad_value:	optional, it's recommended to output bad value and its
39  *		expected value (range).
40  *
41  * Since comma is used to separate the components, only space is allowed
42  * inside each component.
43  */
44 
45 /*
46  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
47  * Allows callers to customize the output.
48  */
49 __printf(3, 4)
50 __cold
generic_err(const struct extent_buffer * eb,int slot,const char * fmt,...)51 static void generic_err(const struct extent_buffer *eb, int slot,
52 			const char *fmt, ...)
53 {
54 	const struct btrfs_fs_info *fs_info = eb->fs_info;
55 	struct va_format vaf;
56 	va_list args;
57 
58 	va_start(args, fmt);
59 
60 	vaf.fmt = fmt;
61 	vaf.va = &args;
62 
63 	btrfs_crit(fs_info,
64 		"corrupt %s: root=%llu block=%llu slot=%d, %pV",
65 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
66 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
67 	va_end(args);
68 }
69 
70 /*
71  * Customized reporter for extent data item, since its key objectid and
72  * offset has its own meaning.
73  */
74 __printf(3, 4)
75 __cold
file_extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)76 static void file_extent_err(const struct extent_buffer *eb, int slot,
77 			    const char *fmt, ...)
78 {
79 	const struct btrfs_fs_info *fs_info = eb->fs_info;
80 	struct btrfs_key key;
81 	struct va_format vaf;
82 	va_list args;
83 
84 	btrfs_item_key_to_cpu(eb, &key, slot);
85 	va_start(args, fmt);
86 
87 	vaf.fmt = fmt;
88 	vaf.va = &args;
89 
90 	btrfs_crit(fs_info,
91 	"corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
92 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
93 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
94 		key.objectid, key.offset, &vaf);
95 	va_end(args);
96 }
97 
98 /*
99  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
100  * Else return 1
101  */
102 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)		      \
103 ({									      \
104 	if (unlikely(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)),      \
105 				 (alignment))))				      \
106 		file_extent_err((leaf), (slot),				      \
107 	"invalid %s for file extent, have %llu, should be aligned to %u",     \
108 			(#name), btrfs_file_extent_##name((leaf), (fi)),      \
109 			(alignment));					      \
110 	(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
111 })
112 
file_extent_end(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_file_extent_item * extent)113 static u64 file_extent_end(struct extent_buffer *leaf,
114 			   struct btrfs_key *key,
115 			   struct btrfs_file_extent_item *extent)
116 {
117 	u64 end;
118 	u64 len;
119 
120 	if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
121 		len = btrfs_file_extent_ram_bytes(leaf, extent);
122 		end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
123 	} else {
124 		len = btrfs_file_extent_num_bytes(leaf, extent);
125 		end = key->offset + len;
126 	}
127 	return end;
128 }
129 
130 /*
131  * Customized report for dir_item, the only new important information is
132  * key->objectid, which represents inode number
133  */
134 __printf(3, 4)
135 __cold
dir_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)136 static void dir_item_err(const struct extent_buffer *eb, int slot,
137 			 const char *fmt, ...)
138 {
139 	const struct btrfs_fs_info *fs_info = eb->fs_info;
140 	struct btrfs_key key;
141 	struct va_format vaf;
142 	va_list args;
143 
144 	btrfs_item_key_to_cpu(eb, &key, slot);
145 	va_start(args, fmt);
146 
147 	vaf.fmt = fmt;
148 	vaf.va = &args;
149 
150 	btrfs_crit(fs_info,
151 		"corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
152 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
153 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
154 		key.objectid, &vaf);
155 	va_end(args);
156 }
157 
158 /*
159  * This functions checks prev_key->objectid, to ensure current key and prev_key
160  * share the same objectid as inode number.
161  *
162  * This is to detect missing INODE_ITEM in subvolume trees.
163  *
164  * Return true if everything is OK or we don't need to check.
165  * Return false if anything is wrong.
166  */
check_prev_ino(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)167 static bool check_prev_ino(struct extent_buffer *leaf,
168 			   struct btrfs_key *key, int slot,
169 			   struct btrfs_key *prev_key)
170 {
171 	/* No prev key, skip check */
172 	if (slot == 0)
173 		return true;
174 
175 	/* Only these key->types needs to be checked */
176 	ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
177 	       key->type == BTRFS_INODE_REF_KEY ||
178 	       key->type == BTRFS_DIR_INDEX_KEY ||
179 	       key->type == BTRFS_DIR_ITEM_KEY ||
180 	       key->type == BTRFS_EXTENT_DATA_KEY);
181 
182 	/*
183 	 * Only subvolume trees along with their reloc trees need this check.
184 	 * Things like log tree doesn't follow this ino requirement.
185 	 */
186 	if (!is_fstree(btrfs_header_owner(leaf)))
187 		return true;
188 
189 	if (key->objectid == prev_key->objectid)
190 		return true;
191 
192 	/* Error found */
193 	dir_item_err(leaf, slot,
194 		"invalid previous key objectid, have %llu expect %llu",
195 		prev_key->objectid, key->objectid);
196 	return false;
197 }
check_extent_data_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)198 static int check_extent_data_item(struct extent_buffer *leaf,
199 				  struct btrfs_key *key, int slot,
200 				  struct btrfs_key *prev_key)
201 {
202 	struct btrfs_fs_info *fs_info = leaf->fs_info;
203 	struct btrfs_file_extent_item *fi;
204 	u32 sectorsize = fs_info->sectorsize;
205 	u32 item_size = btrfs_item_size(leaf, slot);
206 	u64 extent_end;
207 
208 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
209 		file_extent_err(leaf, slot,
210 "unaligned file_offset for file extent, have %llu should be aligned to %u",
211 			key->offset, sectorsize);
212 		return -EUCLEAN;
213 	}
214 
215 	/*
216 	 * Previous key must have the same key->objectid (ino).
217 	 * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
218 	 * But if objectids mismatch, it means we have a missing
219 	 * INODE_ITEM.
220 	 */
221 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
222 		return -EUCLEAN;
223 
224 	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
225 
226 	/*
227 	 * Make sure the item contains at least inline header, so the file
228 	 * extent type is not some garbage.
229 	 */
230 	if (unlikely(item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START)) {
231 		file_extent_err(leaf, slot,
232 				"invalid item size, have %u expect [%zu, %u)",
233 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
234 				SZ_4K);
235 		return -EUCLEAN;
236 	}
237 	if (unlikely(btrfs_file_extent_type(leaf, fi) >=
238 		     BTRFS_NR_FILE_EXTENT_TYPES)) {
239 		file_extent_err(leaf, slot,
240 		"invalid type for file extent, have %u expect range [0, %u]",
241 			btrfs_file_extent_type(leaf, fi),
242 			BTRFS_NR_FILE_EXTENT_TYPES - 1);
243 		return -EUCLEAN;
244 	}
245 
246 	/*
247 	 * Support for new compression/encryption must introduce incompat flag,
248 	 * and must be caught in open_ctree().
249 	 */
250 	if (unlikely(btrfs_file_extent_compression(leaf, fi) >=
251 		     BTRFS_NR_COMPRESS_TYPES)) {
252 		file_extent_err(leaf, slot,
253 	"invalid compression for file extent, have %u expect range [0, %u]",
254 			btrfs_file_extent_compression(leaf, fi),
255 			BTRFS_NR_COMPRESS_TYPES - 1);
256 		return -EUCLEAN;
257 	}
258 	if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
259 		file_extent_err(leaf, slot,
260 			"invalid encryption for file extent, have %u expect 0",
261 			btrfs_file_extent_encryption(leaf, fi));
262 		return -EUCLEAN;
263 	}
264 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
265 		/* Inline extent must have 0 as key offset */
266 		if (unlikely(key->offset)) {
267 			file_extent_err(leaf, slot,
268 		"invalid file_offset for inline file extent, have %llu expect 0",
269 				key->offset);
270 			return -EUCLEAN;
271 		}
272 
273 		/* Compressed inline extent has no on-disk size, skip it */
274 		if (btrfs_file_extent_compression(leaf, fi) !=
275 		    BTRFS_COMPRESS_NONE)
276 			return 0;
277 
278 		/* Uncompressed inline extent size must match item size */
279 		if (unlikely(item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
280 					  btrfs_file_extent_ram_bytes(leaf, fi))) {
281 			file_extent_err(leaf, slot,
282 	"invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
283 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
284 				btrfs_file_extent_ram_bytes(leaf, fi));
285 			return -EUCLEAN;
286 		}
287 		return 0;
288 	}
289 
290 	/* Regular or preallocated extent has fixed item size */
291 	if (unlikely(item_size != sizeof(*fi))) {
292 		file_extent_err(leaf, slot,
293 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
294 			item_size, sizeof(*fi));
295 		return -EUCLEAN;
296 	}
297 	if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
298 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
299 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
300 		     CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
301 		     CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize)))
302 		return -EUCLEAN;
303 
304 	/* Catch extent end overflow */
305 	if (unlikely(check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
306 					key->offset, &extent_end))) {
307 		file_extent_err(leaf, slot,
308 	"extent end overflow, have file offset %llu extent num bytes %llu",
309 				key->offset,
310 				btrfs_file_extent_num_bytes(leaf, fi));
311 		return -EUCLEAN;
312 	}
313 
314 	/*
315 	 * Check that no two consecutive file extent items, in the same leaf,
316 	 * present ranges that overlap each other.
317 	 */
318 	if (slot > 0 &&
319 	    prev_key->objectid == key->objectid &&
320 	    prev_key->type == BTRFS_EXTENT_DATA_KEY) {
321 		struct btrfs_file_extent_item *prev_fi;
322 		u64 prev_end;
323 
324 		prev_fi = btrfs_item_ptr(leaf, slot - 1,
325 					 struct btrfs_file_extent_item);
326 		prev_end = file_extent_end(leaf, prev_key, prev_fi);
327 		if (unlikely(prev_end > key->offset)) {
328 			file_extent_err(leaf, slot - 1,
329 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
330 					prev_end, key->offset);
331 			return -EUCLEAN;
332 		}
333 	}
334 
335 	return 0;
336 }
337 
check_csum_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)338 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
339 			   int slot, struct btrfs_key *prev_key)
340 {
341 	struct btrfs_fs_info *fs_info = leaf->fs_info;
342 	u32 sectorsize = fs_info->sectorsize;
343 	const u32 csumsize = fs_info->csum_size;
344 
345 	if (unlikely(key->objectid != BTRFS_EXTENT_CSUM_OBJECTID)) {
346 		generic_err(leaf, slot,
347 		"invalid key objectid for csum item, have %llu expect %llu",
348 			key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
349 		return -EUCLEAN;
350 	}
351 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
352 		generic_err(leaf, slot,
353 	"unaligned key offset for csum item, have %llu should be aligned to %u",
354 			key->offset, sectorsize);
355 		return -EUCLEAN;
356 	}
357 	if (unlikely(!IS_ALIGNED(btrfs_item_size(leaf, slot), csumsize))) {
358 		generic_err(leaf, slot,
359 	"unaligned item size for csum item, have %u should be aligned to %u",
360 			btrfs_item_size(leaf, slot), csumsize);
361 		return -EUCLEAN;
362 	}
363 	if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
364 		u64 prev_csum_end;
365 		u32 prev_item_size;
366 
367 		prev_item_size = btrfs_item_size(leaf, slot - 1);
368 		prev_csum_end = (prev_item_size / csumsize) * sectorsize;
369 		prev_csum_end += prev_key->offset;
370 		if (unlikely(prev_csum_end > key->offset)) {
371 			generic_err(leaf, slot - 1,
372 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
373 				    prev_csum_end, key->offset);
374 			return -EUCLEAN;
375 		}
376 	}
377 	return 0;
378 }
379 
380 /* Inode item error output has the same format as dir_item_err() */
381 #define inode_item_err(eb, slot, fmt, ...)			\
382 	dir_item_err(eb, slot, fmt, __VA_ARGS__)
383 
check_inode_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)384 static int check_inode_key(struct extent_buffer *leaf, struct btrfs_key *key,
385 			   int slot)
386 {
387 	struct btrfs_key item_key;
388 	bool is_inode_item;
389 
390 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
391 	is_inode_item = (item_key.type == BTRFS_INODE_ITEM_KEY);
392 
393 	/* For XATTR_ITEM, location key should be all 0 */
394 	if (item_key.type == BTRFS_XATTR_ITEM_KEY) {
395 		if (unlikely(key->objectid != 0 || key->type != 0 ||
396 			     key->offset != 0))
397 			return -EUCLEAN;
398 		return 0;
399 	}
400 
401 	if (unlikely((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
402 		      key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
403 		     key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
404 		     key->objectid != BTRFS_FREE_INO_OBJECTID)) {
405 		if (is_inode_item) {
406 			generic_err(leaf, slot,
407 	"invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
408 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
409 				BTRFS_FIRST_FREE_OBJECTID,
410 				BTRFS_LAST_FREE_OBJECTID,
411 				BTRFS_FREE_INO_OBJECTID);
412 		} else {
413 			dir_item_err(leaf, slot,
414 "invalid location key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
415 				key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
416 				BTRFS_FIRST_FREE_OBJECTID,
417 				BTRFS_LAST_FREE_OBJECTID,
418 				BTRFS_FREE_INO_OBJECTID);
419 		}
420 		return -EUCLEAN;
421 	}
422 	if (unlikely(key->offset != 0)) {
423 		if (is_inode_item)
424 			inode_item_err(leaf, slot,
425 				       "invalid key offset: has %llu expect 0",
426 				       key->offset);
427 		else
428 			dir_item_err(leaf, slot,
429 				"invalid location key offset:has %llu expect 0",
430 				key->offset);
431 		return -EUCLEAN;
432 	}
433 	return 0;
434 }
435 
check_root_key(struct extent_buffer * leaf,struct btrfs_key * key,int slot)436 static int check_root_key(struct extent_buffer *leaf, struct btrfs_key *key,
437 			  int slot)
438 {
439 	struct btrfs_key item_key;
440 	bool is_root_item;
441 
442 	btrfs_item_key_to_cpu(leaf, &item_key, slot);
443 	is_root_item = (item_key.type == BTRFS_ROOT_ITEM_KEY);
444 
445 	/*
446 	 * Bad rootid for reloc trees.
447 	 *
448 	 * Reloc trees are only for subvolume trees, other trees only need
449 	 * to be COWed to be relocated.
450 	 */
451 	if (unlikely(is_root_item && key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
452 		     !is_fstree(key->offset))) {
453 		generic_err(leaf, slot,
454 		"invalid reloc tree for root %lld, root id is not a subvolume tree",
455 			    key->offset);
456 		return -EUCLEAN;
457 	}
458 
459 	/* No such tree id */
460 	if (unlikely(key->objectid == 0)) {
461 		if (is_root_item)
462 			generic_err(leaf, slot, "invalid root id 0");
463 		else
464 			dir_item_err(leaf, slot,
465 				     "invalid location key root id 0");
466 		return -EUCLEAN;
467 	}
468 
469 	/* DIR_ITEM/INDEX/INODE_REF is not allowed to point to non-fs trees */
470 	if (unlikely(!is_fstree(key->objectid) && !is_root_item)) {
471 		dir_item_err(leaf, slot,
472 		"invalid location key objectid, have %llu expect [%llu, %llu]",
473 				key->objectid, BTRFS_FIRST_FREE_OBJECTID,
474 				BTRFS_LAST_FREE_OBJECTID);
475 		return -EUCLEAN;
476 	}
477 
478 	/*
479 	 * ROOT_ITEM with non-zero offset means this is a snapshot, created at
480 	 * @offset transid.
481 	 * Furthermore, for location key in DIR_ITEM, its offset is always -1.
482 	 *
483 	 * So here we only check offset for reloc tree whose key->offset must
484 	 * be a valid tree.
485 	 */
486 	if (unlikely(key->objectid == BTRFS_TREE_RELOC_OBJECTID &&
487 		     key->offset == 0)) {
488 		generic_err(leaf, slot, "invalid root id 0 for reloc tree");
489 		return -EUCLEAN;
490 	}
491 	return 0;
492 }
493 
check_dir_item(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_key * prev_key,int slot)494 static int check_dir_item(struct extent_buffer *leaf,
495 			  struct btrfs_key *key, struct btrfs_key *prev_key,
496 			  int slot)
497 {
498 	struct btrfs_fs_info *fs_info = leaf->fs_info;
499 	struct btrfs_dir_item *di;
500 	u32 item_size = btrfs_item_size(leaf, slot);
501 	u32 cur = 0;
502 
503 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
504 		return -EUCLEAN;
505 
506 	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
507 	while (cur < item_size) {
508 		struct btrfs_key location_key;
509 		u32 name_len;
510 		u32 data_len;
511 		u32 max_name_len;
512 		u32 total_size;
513 		u32 name_hash;
514 		u8 dir_type;
515 		int ret;
516 
517 		/* header itself should not cross item boundary */
518 		if (unlikely(cur + sizeof(*di) > item_size)) {
519 			dir_item_err(leaf, slot,
520 		"dir item header crosses item boundary, have %zu boundary %u",
521 				cur + sizeof(*di), item_size);
522 			return -EUCLEAN;
523 		}
524 
525 		/* Location key check */
526 		btrfs_dir_item_key_to_cpu(leaf, di, &location_key);
527 		if (location_key.type == BTRFS_ROOT_ITEM_KEY) {
528 			ret = check_root_key(leaf, &location_key, slot);
529 			if (unlikely(ret < 0))
530 				return ret;
531 		} else if (location_key.type == BTRFS_INODE_ITEM_KEY ||
532 			   location_key.type == 0) {
533 			ret = check_inode_key(leaf, &location_key, slot);
534 			if (unlikely(ret < 0))
535 				return ret;
536 		} else {
537 			dir_item_err(leaf, slot,
538 			"invalid location key type, have %u, expect %u or %u",
539 				     location_key.type, BTRFS_ROOT_ITEM_KEY,
540 				     BTRFS_INODE_ITEM_KEY);
541 			return -EUCLEAN;
542 		}
543 
544 		/* dir type check */
545 		dir_type = btrfs_dir_type(leaf, di);
546 		if (unlikely(dir_type >= BTRFS_FT_MAX)) {
547 			dir_item_err(leaf, slot,
548 			"invalid dir item type, have %u expect [0, %u)",
549 				dir_type, BTRFS_FT_MAX);
550 			return -EUCLEAN;
551 		}
552 
553 		if (unlikely(key->type == BTRFS_XATTR_ITEM_KEY &&
554 			     dir_type != BTRFS_FT_XATTR)) {
555 			dir_item_err(leaf, slot,
556 		"invalid dir item type for XATTR key, have %u expect %u",
557 				dir_type, BTRFS_FT_XATTR);
558 			return -EUCLEAN;
559 		}
560 		if (unlikely(dir_type == BTRFS_FT_XATTR &&
561 			     key->type != BTRFS_XATTR_ITEM_KEY)) {
562 			dir_item_err(leaf, slot,
563 			"xattr dir type found for non-XATTR key");
564 			return -EUCLEAN;
565 		}
566 		if (dir_type == BTRFS_FT_XATTR)
567 			max_name_len = XATTR_NAME_MAX;
568 		else
569 			max_name_len = BTRFS_NAME_LEN;
570 
571 		/* Name/data length check */
572 		name_len = btrfs_dir_name_len(leaf, di);
573 		data_len = btrfs_dir_data_len(leaf, di);
574 		if (unlikely(name_len > max_name_len)) {
575 			dir_item_err(leaf, slot,
576 			"dir item name len too long, have %u max %u",
577 				name_len, max_name_len);
578 			return -EUCLEAN;
579 		}
580 		if (unlikely(name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info))) {
581 			dir_item_err(leaf, slot,
582 			"dir item name and data len too long, have %u max %u",
583 				name_len + data_len,
584 				BTRFS_MAX_XATTR_SIZE(fs_info));
585 			return -EUCLEAN;
586 		}
587 
588 		if (unlikely(data_len && dir_type != BTRFS_FT_XATTR)) {
589 			dir_item_err(leaf, slot,
590 			"dir item with invalid data len, have %u expect 0",
591 				data_len);
592 			return -EUCLEAN;
593 		}
594 
595 		total_size = sizeof(*di) + name_len + data_len;
596 
597 		/* header and name/data should not cross item boundary */
598 		if (unlikely(cur + total_size > item_size)) {
599 			dir_item_err(leaf, slot,
600 		"dir item data crosses item boundary, have %u boundary %u",
601 				cur + total_size, item_size);
602 			return -EUCLEAN;
603 		}
604 
605 		/*
606 		 * Special check for XATTR/DIR_ITEM, as key->offset is name
607 		 * hash, should match its name
608 		 */
609 		if (key->type == BTRFS_DIR_ITEM_KEY ||
610 		    key->type == BTRFS_XATTR_ITEM_KEY) {
611 			char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
612 
613 			read_extent_buffer(leaf, namebuf,
614 					(unsigned long)(di + 1), name_len);
615 			name_hash = btrfs_name_hash(namebuf, name_len);
616 			if (unlikely(key->offset != name_hash)) {
617 				dir_item_err(leaf, slot,
618 		"name hash mismatch with key, have 0x%016x expect 0x%016llx",
619 					name_hash, key->offset);
620 				return -EUCLEAN;
621 			}
622 		}
623 		cur += total_size;
624 		di = (struct btrfs_dir_item *)((void *)di + total_size);
625 	}
626 	return 0;
627 }
628 
629 __printf(3, 4)
630 __cold
block_group_err(const struct extent_buffer * eb,int slot,const char * fmt,...)631 static void block_group_err(const struct extent_buffer *eb, int slot,
632 			    const char *fmt, ...)
633 {
634 	const struct btrfs_fs_info *fs_info = eb->fs_info;
635 	struct btrfs_key key;
636 	struct va_format vaf;
637 	va_list args;
638 
639 	btrfs_item_key_to_cpu(eb, &key, slot);
640 	va_start(args, fmt);
641 
642 	vaf.fmt = fmt;
643 	vaf.va = &args;
644 
645 	btrfs_crit(fs_info,
646 	"corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
647 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
648 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
649 		key.objectid, key.offset, &vaf);
650 	va_end(args);
651 }
652 
check_block_group_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)653 static int check_block_group_item(struct extent_buffer *leaf,
654 				  struct btrfs_key *key, int slot)
655 {
656 	struct btrfs_fs_info *fs_info = leaf->fs_info;
657 	struct btrfs_block_group_item bgi;
658 	u32 item_size = btrfs_item_size(leaf, slot);
659 	u64 chunk_objectid;
660 	u64 flags;
661 	u64 type;
662 
663 	/*
664 	 * Here we don't really care about alignment since extent allocator can
665 	 * handle it.  We care more about the size.
666 	 */
667 	if (unlikely(key->offset == 0)) {
668 		block_group_err(leaf, slot,
669 				"invalid block group size 0");
670 		return -EUCLEAN;
671 	}
672 
673 	if (unlikely(item_size != sizeof(bgi))) {
674 		block_group_err(leaf, slot,
675 			"invalid item size, have %u expect %zu",
676 				item_size, sizeof(bgi));
677 		return -EUCLEAN;
678 	}
679 
680 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
681 			   sizeof(bgi));
682 	chunk_objectid = btrfs_stack_block_group_chunk_objectid(&bgi);
683 	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
684 		/*
685 		 * We don't init the nr_global_roots until we load the global
686 		 * roots, so this could be 0 at mount time.  If it's 0 we'll
687 		 * just assume we're fine, and later we'll check against our
688 		 * actual value.
689 		 */
690 		if (unlikely(fs_info->nr_global_roots &&
691 			     chunk_objectid >= fs_info->nr_global_roots)) {
692 			block_group_err(leaf, slot,
693 	"invalid block group global root id, have %llu, needs to be <= %llu",
694 					chunk_objectid,
695 					fs_info->nr_global_roots);
696 			return -EUCLEAN;
697 		}
698 	} else if (unlikely(chunk_objectid != BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
699 		block_group_err(leaf, slot,
700 		"invalid block group chunk objectid, have %llu expect %llu",
701 				btrfs_stack_block_group_chunk_objectid(&bgi),
702 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
703 		return -EUCLEAN;
704 	}
705 
706 	if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
707 		block_group_err(leaf, slot,
708 			"invalid block group used, have %llu expect [0, %llu)",
709 				btrfs_stack_block_group_used(&bgi), key->offset);
710 		return -EUCLEAN;
711 	}
712 
713 	flags = btrfs_stack_block_group_flags(&bgi);
714 	if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
715 		block_group_err(leaf, slot,
716 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
717 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
718 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
719 		return -EUCLEAN;
720 	}
721 
722 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
723 	if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
724 		     type != BTRFS_BLOCK_GROUP_METADATA &&
725 		     type != BTRFS_BLOCK_GROUP_SYSTEM &&
726 		     type != (BTRFS_BLOCK_GROUP_METADATA |
727 			      BTRFS_BLOCK_GROUP_DATA))) {
728 		block_group_err(leaf, slot,
729 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
730 			type, hweight64(type),
731 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
732 			BTRFS_BLOCK_GROUP_SYSTEM,
733 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
734 		return -EUCLEAN;
735 	}
736 	return 0;
737 }
738 
739 __printf(4, 5)
740 __cold
chunk_err(const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,const char * fmt,...)741 static void chunk_err(const struct extent_buffer *leaf,
742 		      const struct btrfs_chunk *chunk, u64 logical,
743 		      const char *fmt, ...)
744 {
745 	const struct btrfs_fs_info *fs_info = leaf->fs_info;
746 	bool is_sb;
747 	struct va_format vaf;
748 	va_list args;
749 	int i;
750 	int slot = -1;
751 
752 	/* Only superblock eb is able to have such small offset */
753 	is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
754 
755 	if (!is_sb) {
756 		/*
757 		 * Get the slot number by iterating through all slots, this
758 		 * would provide better readability.
759 		 */
760 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
761 			if (btrfs_item_ptr_offset(leaf, i) ==
762 					(unsigned long)chunk) {
763 				slot = i;
764 				break;
765 			}
766 		}
767 	}
768 	va_start(args, fmt);
769 	vaf.fmt = fmt;
770 	vaf.va = &args;
771 
772 	if (is_sb)
773 		btrfs_crit(fs_info,
774 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
775 			   logical, &vaf);
776 	else
777 		btrfs_crit(fs_info,
778 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
779 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
780 			   logical, &vaf);
781 	va_end(args);
782 }
783 
784 /*
785  * The common chunk check which could also work on super block sys chunk array.
786  *
787  * Return -EUCLEAN if anything is corrupted.
788  * Return 0 if everything is OK.
789  */
btrfs_check_chunk_valid(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 logical)790 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
791 			    struct btrfs_chunk *chunk, u64 logical)
792 {
793 	struct btrfs_fs_info *fs_info = leaf->fs_info;
794 	u64 length;
795 	u64 chunk_end;
796 	u64 stripe_len;
797 	u16 num_stripes;
798 	u16 sub_stripes;
799 	u64 type;
800 	u64 features;
801 	bool mixed = false;
802 	int raid_index;
803 	int nparity;
804 	int ncopies;
805 
806 	length = btrfs_chunk_length(leaf, chunk);
807 	stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
808 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
809 	sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
810 	type = btrfs_chunk_type(leaf, chunk);
811 	raid_index = btrfs_bg_flags_to_raid_index(type);
812 	ncopies = btrfs_raid_array[raid_index].ncopies;
813 	nparity = btrfs_raid_array[raid_index].nparity;
814 
815 	if (unlikely(!num_stripes)) {
816 		chunk_err(leaf, chunk, logical,
817 			  "invalid chunk num_stripes, have %u", num_stripes);
818 		return -EUCLEAN;
819 	}
820 	if (unlikely(num_stripes < ncopies)) {
821 		chunk_err(leaf, chunk, logical,
822 			  "invalid chunk num_stripes < ncopies, have %u < %d",
823 			  num_stripes, ncopies);
824 		return -EUCLEAN;
825 	}
826 	if (unlikely(nparity && num_stripes == nparity)) {
827 		chunk_err(leaf, chunk, logical,
828 			  "invalid chunk num_stripes == nparity, have %u == %d",
829 			  num_stripes, nparity);
830 		return -EUCLEAN;
831 	}
832 	if (unlikely(!IS_ALIGNED(logical, fs_info->sectorsize))) {
833 		chunk_err(leaf, chunk, logical,
834 		"invalid chunk logical, have %llu should aligned to %u",
835 			  logical, fs_info->sectorsize);
836 		return -EUCLEAN;
837 	}
838 	if (unlikely(btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize)) {
839 		chunk_err(leaf, chunk, logical,
840 			  "invalid chunk sectorsize, have %u expect %u",
841 			  btrfs_chunk_sector_size(leaf, chunk),
842 			  fs_info->sectorsize);
843 		return -EUCLEAN;
844 	}
845 	if (unlikely(!length || !IS_ALIGNED(length, fs_info->sectorsize))) {
846 		chunk_err(leaf, chunk, logical,
847 			  "invalid chunk length, have %llu", length);
848 		return -EUCLEAN;
849 	}
850 	if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
851 		chunk_err(leaf, chunk, logical,
852 "invalid chunk logical start and length, have logical start %llu length %llu",
853 			  logical, length);
854 		return -EUCLEAN;
855 	}
856 	if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
857 		chunk_err(leaf, chunk, logical,
858 			  "invalid chunk stripe length: %llu",
859 			  stripe_len);
860 		return -EUCLEAN;
861 	}
862 	if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
863 			      BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
864 		chunk_err(leaf, chunk, logical,
865 			  "unrecognized chunk type: 0x%llx",
866 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
867 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) &
868 			  btrfs_chunk_type(leaf, chunk));
869 		return -EUCLEAN;
870 	}
871 
872 	if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
873 		     (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
874 		chunk_err(leaf, chunk, logical,
875 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
876 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
877 		return -EUCLEAN;
878 	}
879 	if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
880 		chunk_err(leaf, chunk, logical,
881 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
882 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
883 		return -EUCLEAN;
884 	}
885 
886 	if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
887 		     (type & (BTRFS_BLOCK_GROUP_METADATA |
888 			      BTRFS_BLOCK_GROUP_DATA)))) {
889 		chunk_err(leaf, chunk, logical,
890 			  "system chunk with data or metadata type: 0x%llx",
891 			  type);
892 		return -EUCLEAN;
893 	}
894 
895 	features = btrfs_super_incompat_flags(fs_info->super_copy);
896 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
897 		mixed = true;
898 
899 	if (!mixed) {
900 		if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
901 			     (type & BTRFS_BLOCK_GROUP_DATA))) {
902 			chunk_err(leaf, chunk, logical,
903 			"mixed chunk type in non-mixed mode: 0x%llx", type);
904 			return -EUCLEAN;
905 		}
906 	}
907 
908 	if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
909 		      sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
910 		     (type & BTRFS_BLOCK_GROUP_RAID1 &&
911 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
912 		     (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
913 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
914 		     (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
915 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
916 		     (type & BTRFS_BLOCK_GROUP_RAID5 &&
917 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
918 		     (type & BTRFS_BLOCK_GROUP_RAID6 &&
919 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
920 		     (type & BTRFS_BLOCK_GROUP_DUP &&
921 		      num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
922 		     ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
923 		      num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
924 		chunk_err(leaf, chunk, logical,
925 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
926 			num_stripes, sub_stripes,
927 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
928 		return -EUCLEAN;
929 	}
930 
931 	return 0;
932 }
933 
934 /*
935  * Enhanced version of chunk item checker.
936  *
937  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
938  * to work on super block sys_chunk_array which doesn't have full item ptr.
939  */
check_leaf_chunk_item(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_key * key,int slot)940 static int check_leaf_chunk_item(struct extent_buffer *leaf,
941 				 struct btrfs_chunk *chunk,
942 				 struct btrfs_key *key, int slot)
943 {
944 	int num_stripes;
945 
946 	if (unlikely(btrfs_item_size(leaf, slot) < sizeof(struct btrfs_chunk))) {
947 		chunk_err(leaf, chunk, key->offset,
948 			"invalid chunk item size: have %u expect [%zu, %u)",
949 			btrfs_item_size(leaf, slot),
950 			sizeof(struct btrfs_chunk),
951 			BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
952 		return -EUCLEAN;
953 	}
954 
955 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
956 	/* Let btrfs_check_chunk_valid() handle this error type */
957 	if (num_stripes == 0)
958 		goto out;
959 
960 	if (unlikely(btrfs_chunk_item_size(num_stripes) !=
961 		     btrfs_item_size(leaf, slot))) {
962 		chunk_err(leaf, chunk, key->offset,
963 			"invalid chunk item size: have %u expect %lu",
964 			btrfs_item_size(leaf, slot),
965 			btrfs_chunk_item_size(num_stripes));
966 		return -EUCLEAN;
967 	}
968 out:
969 	return btrfs_check_chunk_valid(leaf, chunk, key->offset);
970 }
971 
972 __printf(3, 4)
973 __cold
dev_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)974 static void dev_item_err(const struct extent_buffer *eb, int slot,
975 			 const char *fmt, ...)
976 {
977 	struct btrfs_key key;
978 	struct va_format vaf;
979 	va_list args;
980 
981 	btrfs_item_key_to_cpu(eb, &key, slot);
982 	va_start(args, fmt);
983 
984 	vaf.fmt = fmt;
985 	vaf.va = &args;
986 
987 	btrfs_crit(eb->fs_info,
988 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
989 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
990 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
991 		key.objectid, &vaf);
992 	va_end(args);
993 }
994 
check_dev_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)995 static int check_dev_item(struct extent_buffer *leaf,
996 			  struct btrfs_key *key, int slot)
997 {
998 	struct btrfs_dev_item *ditem;
999 	const u32 item_size = btrfs_item_size(leaf, slot);
1000 
1001 	if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
1002 		dev_item_err(leaf, slot,
1003 			     "invalid objectid: has=%llu expect=%llu",
1004 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
1005 		return -EUCLEAN;
1006 	}
1007 
1008 	if (unlikely(item_size != sizeof(*ditem))) {
1009 		dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
1010 			     item_size, sizeof(*ditem));
1011 		return -EUCLEAN;
1012 	}
1013 
1014 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
1015 	if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
1016 		dev_item_err(leaf, slot,
1017 			     "devid mismatch: key has=%llu item has=%llu",
1018 			     key->offset, btrfs_device_id(leaf, ditem));
1019 		return -EUCLEAN;
1020 	}
1021 
1022 	/*
1023 	 * For device total_bytes, we don't have reliable way to check it, as
1024 	 * it can be 0 for device removal. Device size check can only be done
1025 	 * by dev extents check.
1026 	 */
1027 	if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1028 		     btrfs_device_total_bytes(leaf, ditem))) {
1029 		dev_item_err(leaf, slot,
1030 			     "invalid bytes used: have %llu expect [0, %llu]",
1031 			     btrfs_device_bytes_used(leaf, ditem),
1032 			     btrfs_device_total_bytes(leaf, ditem));
1033 		return -EUCLEAN;
1034 	}
1035 	/*
1036 	 * Remaining members like io_align/type/gen/dev_group aren't really
1037 	 * utilized.  Skip them to make later usage of them easier.
1038 	 */
1039 	return 0;
1040 }
1041 
check_inode_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1042 static int check_inode_item(struct extent_buffer *leaf,
1043 			    struct btrfs_key *key, int slot)
1044 {
1045 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1046 	struct btrfs_inode_item *iitem;
1047 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1048 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1049 	const u32 item_size = btrfs_item_size(leaf, slot);
1050 	u32 mode;
1051 	int ret;
1052 	u32 flags;
1053 	u32 ro_flags;
1054 
1055 	ret = check_inode_key(leaf, key, slot);
1056 	if (unlikely(ret < 0))
1057 		return ret;
1058 
1059 	if (unlikely(item_size != sizeof(*iitem))) {
1060 		generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1061 			    item_size, sizeof(*iitem));
1062 		return -EUCLEAN;
1063 	}
1064 
1065 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1066 
1067 	/* Here we use super block generation + 1 to handle log tree */
1068 	if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1069 		inode_item_err(leaf, slot,
1070 			"invalid inode generation: has %llu expect (0, %llu]",
1071 			       btrfs_inode_generation(leaf, iitem),
1072 			       super_gen + 1);
1073 		return -EUCLEAN;
1074 	}
1075 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1076 	if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1077 		inode_item_err(leaf, slot,
1078 			"invalid inode transid: has %llu expect [0, %llu]",
1079 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
1080 		return -EUCLEAN;
1081 	}
1082 
1083 	/*
1084 	 * For size and nbytes it's better not to be too strict, as for dir
1085 	 * item its size/nbytes can easily get wrong, but doesn't affect
1086 	 * anything in the fs. So here we skip the check.
1087 	 */
1088 	mode = btrfs_inode_mode(leaf, iitem);
1089 	if (unlikely(mode & ~valid_mask)) {
1090 		inode_item_err(leaf, slot,
1091 			       "unknown mode bit detected: 0x%x",
1092 			       mode & ~valid_mask);
1093 		return -EUCLEAN;
1094 	}
1095 
1096 	/*
1097 	 * S_IFMT is not bit mapped so we can't completely rely on
1098 	 * is_power_of_2/has_single_bit_set, but it can save us from checking
1099 	 * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1100 	 */
1101 	if (!has_single_bit_set(mode & S_IFMT)) {
1102 		if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1103 			inode_item_err(leaf, slot,
1104 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
1105 				       mode & S_IFMT);
1106 			return -EUCLEAN;
1107 		}
1108 	}
1109 	if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1110 		inode_item_err(leaf, slot,
1111 		       "invalid nlink: has %u expect no more than 1 for dir",
1112 			btrfs_inode_nlink(leaf, iitem));
1113 		return -EUCLEAN;
1114 	}
1115 	btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1116 	if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1117 		inode_item_err(leaf, slot,
1118 			       "unknown incompat flags detected: 0x%x", flags);
1119 		return -EUCLEAN;
1120 	}
1121 	if (unlikely(!sb_rdonly(fs_info->sb) &&
1122 		     (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1123 		inode_item_err(leaf, slot,
1124 			"unknown ro-compat flags detected on writeable mount: 0x%x",
1125 			ro_flags);
1126 		return -EUCLEAN;
1127 	}
1128 	return 0;
1129 }
1130 
check_root_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1131 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1132 			   int slot)
1133 {
1134 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1135 	struct btrfs_root_item ri = { 0 };
1136 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1137 				     BTRFS_ROOT_SUBVOL_DEAD;
1138 	int ret;
1139 
1140 	ret = check_root_key(leaf, key, slot);
1141 	if (unlikely(ret < 0))
1142 		return ret;
1143 
1144 	if (unlikely(btrfs_item_size(leaf, slot) != sizeof(ri) &&
1145 		     btrfs_item_size(leaf, slot) !=
1146 		     btrfs_legacy_root_item_size())) {
1147 		generic_err(leaf, slot,
1148 			    "invalid root item size, have %u expect %zu or %u",
1149 			    btrfs_item_size(leaf, slot), sizeof(ri),
1150 			    btrfs_legacy_root_item_size());
1151 		return -EUCLEAN;
1152 	}
1153 
1154 	/*
1155 	 * For legacy root item, the members starting at generation_v2 will be
1156 	 * all filled with 0.
1157 	 * And since we allow geneartion_v2 as 0, it will still pass the check.
1158 	 */
1159 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1160 			   btrfs_item_size(leaf, slot));
1161 
1162 	/* Generation related */
1163 	if (unlikely(btrfs_root_generation(&ri) >
1164 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1165 		generic_err(leaf, slot,
1166 			"invalid root generation, have %llu expect (0, %llu]",
1167 			    btrfs_root_generation(&ri),
1168 			    btrfs_super_generation(fs_info->super_copy) + 1);
1169 		return -EUCLEAN;
1170 	}
1171 	if (unlikely(btrfs_root_generation_v2(&ri) >
1172 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1173 		generic_err(leaf, slot,
1174 		"invalid root v2 generation, have %llu expect (0, %llu]",
1175 			    btrfs_root_generation_v2(&ri),
1176 			    btrfs_super_generation(fs_info->super_copy) + 1);
1177 		return -EUCLEAN;
1178 	}
1179 	if (unlikely(btrfs_root_last_snapshot(&ri) >
1180 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1181 		generic_err(leaf, slot,
1182 		"invalid root last_snapshot, have %llu expect (0, %llu]",
1183 			    btrfs_root_last_snapshot(&ri),
1184 			    btrfs_super_generation(fs_info->super_copy) + 1);
1185 		return -EUCLEAN;
1186 	}
1187 
1188 	/* Alignment and level check */
1189 	if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1190 		generic_err(leaf, slot,
1191 		"invalid root bytenr, have %llu expect to be aligned to %u",
1192 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
1193 		return -EUCLEAN;
1194 	}
1195 	if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1196 		generic_err(leaf, slot,
1197 			    "invalid root level, have %u expect [0, %u]",
1198 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1199 		return -EUCLEAN;
1200 	}
1201 	if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1202 		generic_err(leaf, slot,
1203 			    "invalid root level, have %u expect [0, %u]",
1204 			    btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1205 		return -EUCLEAN;
1206 	}
1207 
1208 	/* Flags check */
1209 	if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1210 		generic_err(leaf, slot,
1211 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
1212 			    btrfs_root_flags(&ri), valid_root_flags);
1213 		return -EUCLEAN;
1214 	}
1215 	return 0;
1216 }
1217 
1218 __printf(3,4)
1219 __cold
extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)1220 static void extent_err(const struct extent_buffer *eb, int slot,
1221 		       const char *fmt, ...)
1222 {
1223 	struct btrfs_key key;
1224 	struct va_format vaf;
1225 	va_list args;
1226 	u64 bytenr;
1227 	u64 len;
1228 
1229 	btrfs_item_key_to_cpu(eb, &key, slot);
1230 	bytenr = key.objectid;
1231 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
1232 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1233 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1234 		len = eb->fs_info->nodesize;
1235 	else
1236 		len = key.offset;
1237 	va_start(args, fmt);
1238 
1239 	vaf.fmt = fmt;
1240 	vaf.va = &args;
1241 
1242 	btrfs_crit(eb->fs_info,
1243 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1244 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1245 		eb->start, slot, bytenr, len, &vaf);
1246 	va_end(args);
1247 }
1248 
check_extent_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1249 static int check_extent_item(struct extent_buffer *leaf,
1250 			     struct btrfs_key *key, int slot,
1251 			     struct btrfs_key *prev_key)
1252 {
1253 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1254 	struct btrfs_extent_item *ei;
1255 	bool is_tree_block = false;
1256 	unsigned long ptr;	/* Current pointer inside inline refs */
1257 	unsigned long end;	/* Extent item end */
1258 	const u32 item_size = btrfs_item_size(leaf, slot);
1259 	u64 flags;
1260 	u64 generation;
1261 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1262 	u64 inline_refs = 0;	/* found total inline refs */
1263 
1264 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1265 		     !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1266 		generic_err(leaf, slot,
1267 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1268 		return -EUCLEAN;
1269 	}
1270 	/* key->objectid is the bytenr for both key types */
1271 	if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1272 		generic_err(leaf, slot,
1273 		"invalid key objectid, have %llu expect to be aligned to %u",
1274 			   key->objectid, fs_info->sectorsize);
1275 		return -EUCLEAN;
1276 	}
1277 
1278 	/* key->offset is tree level for METADATA_ITEM_KEY */
1279 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1280 		     key->offset >= BTRFS_MAX_LEVEL)) {
1281 		extent_err(leaf, slot,
1282 			   "invalid tree level, have %llu expect [0, %u]",
1283 			   key->offset, BTRFS_MAX_LEVEL - 1);
1284 		return -EUCLEAN;
1285 	}
1286 
1287 	/*
1288 	 * EXTENT/METADATA_ITEM consists of:
1289 	 * 1) One btrfs_extent_item
1290 	 *    Records the total refs, type and generation of the extent.
1291 	 *
1292 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1293 	 *    Records the first key and level of the tree block.
1294 	 *
1295 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1296 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1297 	 *    2.1) The ref type, one of the 4
1298 	 *         TREE_BLOCK_REF	Tree block only
1299 	 *         SHARED_BLOCK_REF	Tree block only
1300 	 *         EXTENT_DATA_REF	Data only
1301 	 *         SHARED_DATA_REF	Data only
1302 	 *    2.2) Ref type specific data
1303 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1304 	 *         data structure.
1305 	 */
1306 	if (unlikely(item_size < sizeof(*ei))) {
1307 		extent_err(leaf, slot,
1308 			   "invalid item size, have %u expect [%zu, %u)",
1309 			   item_size, sizeof(*ei),
1310 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1311 		return -EUCLEAN;
1312 	}
1313 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1314 
1315 	/* Checks against extent_item */
1316 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1317 	flags = btrfs_extent_flags(leaf, ei);
1318 	total_refs = btrfs_extent_refs(leaf, ei);
1319 	generation = btrfs_extent_generation(leaf, ei);
1320 	if (unlikely(generation >
1321 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1322 		extent_err(leaf, slot,
1323 			   "invalid generation, have %llu expect (0, %llu]",
1324 			   generation,
1325 			   btrfs_super_generation(fs_info->super_copy) + 1);
1326 		return -EUCLEAN;
1327 	}
1328 	if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1329 						  BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1330 		extent_err(leaf, slot,
1331 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1332 			flags, BTRFS_EXTENT_FLAG_DATA |
1333 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1334 		return -EUCLEAN;
1335 	}
1336 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1337 	if (is_tree_block) {
1338 		if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1339 			     key->offset != fs_info->nodesize)) {
1340 			extent_err(leaf, slot,
1341 				   "invalid extent length, have %llu expect %u",
1342 				   key->offset, fs_info->nodesize);
1343 			return -EUCLEAN;
1344 		}
1345 	} else {
1346 		if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1347 			extent_err(leaf, slot,
1348 			"invalid key type, have %u expect %u for data backref",
1349 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1350 			return -EUCLEAN;
1351 		}
1352 		if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1353 			extent_err(leaf, slot,
1354 			"invalid extent length, have %llu expect aligned to %u",
1355 				   key->offset, fs_info->sectorsize);
1356 			return -EUCLEAN;
1357 		}
1358 		if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1359 			extent_err(leaf, slot,
1360 			"invalid extent flag, data has full backref set");
1361 			return -EUCLEAN;
1362 		}
1363 	}
1364 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1365 
1366 	/* Check the special case of btrfs_tree_block_info */
1367 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1368 		struct btrfs_tree_block_info *info;
1369 
1370 		info = (struct btrfs_tree_block_info *)ptr;
1371 		if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1372 			extent_err(leaf, slot,
1373 			"invalid tree block info level, have %u expect [0, %u]",
1374 				   btrfs_tree_block_level(leaf, info),
1375 				   BTRFS_MAX_LEVEL - 1);
1376 			return -EUCLEAN;
1377 		}
1378 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1379 	}
1380 
1381 	/* Check inline refs */
1382 	while (ptr < end) {
1383 		struct btrfs_extent_inline_ref *iref;
1384 		struct btrfs_extent_data_ref *dref;
1385 		struct btrfs_shared_data_ref *sref;
1386 		u64 dref_offset;
1387 		u64 inline_offset;
1388 		u8 inline_type;
1389 
1390 		if (unlikely(ptr + sizeof(*iref) > end)) {
1391 			extent_err(leaf, slot,
1392 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1393 				   ptr, sizeof(*iref), end);
1394 			return -EUCLEAN;
1395 		}
1396 		iref = (struct btrfs_extent_inline_ref *)ptr;
1397 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1398 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1399 		if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1400 			extent_err(leaf, slot,
1401 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1402 				   ptr, btrfs_extent_inline_ref_size(inline_type), end);
1403 			return -EUCLEAN;
1404 		}
1405 
1406 		switch (inline_type) {
1407 		/* inline_offset is subvolid of the owner, no need to check */
1408 		case BTRFS_TREE_BLOCK_REF_KEY:
1409 			inline_refs++;
1410 			break;
1411 		/* Contains parent bytenr */
1412 		case BTRFS_SHARED_BLOCK_REF_KEY:
1413 			if (unlikely(!IS_ALIGNED(inline_offset,
1414 						 fs_info->sectorsize))) {
1415 				extent_err(leaf, slot,
1416 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1417 					   inline_offset, fs_info->sectorsize);
1418 				return -EUCLEAN;
1419 			}
1420 			inline_refs++;
1421 			break;
1422 		/*
1423 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1424 		 * The only obvious corruption can happen in that offset.
1425 		 */
1426 		case BTRFS_EXTENT_DATA_REF_KEY:
1427 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1428 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1429 			if (unlikely(!IS_ALIGNED(dref_offset,
1430 						 fs_info->sectorsize))) {
1431 				extent_err(leaf, slot,
1432 		"invalid data ref offset, have %llu expect aligned to %u",
1433 					   dref_offset, fs_info->sectorsize);
1434 				return -EUCLEAN;
1435 			}
1436 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1437 			break;
1438 		/* Contains parent bytenr and ref count */
1439 		case BTRFS_SHARED_DATA_REF_KEY:
1440 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1441 			if (unlikely(!IS_ALIGNED(inline_offset,
1442 						 fs_info->sectorsize))) {
1443 				extent_err(leaf, slot,
1444 		"invalid data parent bytenr, have %llu expect aligned to %u",
1445 					   inline_offset, fs_info->sectorsize);
1446 				return -EUCLEAN;
1447 			}
1448 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1449 			break;
1450 		default:
1451 			extent_err(leaf, slot, "unknown inline ref type: %u",
1452 				   inline_type);
1453 			return -EUCLEAN;
1454 		}
1455 		ptr += btrfs_extent_inline_ref_size(inline_type);
1456 	}
1457 	/* No padding is allowed */
1458 	if (unlikely(ptr != end)) {
1459 		extent_err(leaf, slot,
1460 			   "invalid extent item size, padding bytes found");
1461 		return -EUCLEAN;
1462 	}
1463 
1464 	/* Finally, check the inline refs against total refs */
1465 	if (unlikely(inline_refs > total_refs)) {
1466 		extent_err(leaf, slot,
1467 			"invalid extent refs, have %llu expect >= inline %llu",
1468 			   total_refs, inline_refs);
1469 		return -EUCLEAN;
1470 	}
1471 
1472 	if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1473 	    (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1474 		u64 prev_end = prev_key->objectid;
1475 
1476 		if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1477 			prev_end += fs_info->nodesize;
1478 		else
1479 			prev_end += prev_key->offset;
1480 
1481 		if (unlikely(prev_end > key->objectid)) {
1482 			extent_err(leaf, slot,
1483 	"previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1484 				   prev_key->objectid, prev_key->type,
1485 				   prev_key->offset, key->objectid, key->type,
1486 				   key->offset);
1487 			return -EUCLEAN;
1488 		}
1489 	}
1490 
1491 	return 0;
1492 }
1493 
check_simple_keyed_refs(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1494 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1495 				   struct btrfs_key *key, int slot)
1496 {
1497 	u32 expect_item_size = 0;
1498 
1499 	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1500 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1501 
1502 	if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
1503 		generic_err(leaf, slot,
1504 		"invalid item size, have %u expect %u for key type %u",
1505 			    btrfs_item_size(leaf, slot),
1506 			    expect_item_size, key->type);
1507 		return -EUCLEAN;
1508 	}
1509 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1510 		generic_err(leaf, slot,
1511 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1512 			    key->objectid, leaf->fs_info->sectorsize);
1513 		return -EUCLEAN;
1514 	}
1515 	if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1516 		     !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1517 		extent_err(leaf, slot,
1518 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1519 			   key->offset, leaf->fs_info->sectorsize);
1520 		return -EUCLEAN;
1521 	}
1522 	return 0;
1523 }
1524 
check_extent_data_ref(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1525 static int check_extent_data_ref(struct extent_buffer *leaf,
1526 				 struct btrfs_key *key, int slot)
1527 {
1528 	struct btrfs_extent_data_ref *dref;
1529 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1530 	const unsigned long end = ptr + btrfs_item_size(leaf, slot);
1531 
1532 	if (unlikely(btrfs_item_size(leaf, slot) % sizeof(*dref) != 0)) {
1533 		generic_err(leaf, slot,
1534 	"invalid item size, have %u expect aligned to %zu for key type %u",
1535 			    btrfs_item_size(leaf, slot),
1536 			    sizeof(*dref), key->type);
1537 		return -EUCLEAN;
1538 	}
1539 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1540 		generic_err(leaf, slot,
1541 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1542 			    key->objectid, leaf->fs_info->sectorsize);
1543 		return -EUCLEAN;
1544 	}
1545 	for (; ptr < end; ptr += sizeof(*dref)) {
1546 		u64 offset;
1547 
1548 		/*
1549 		 * We cannot check the extent_data_ref hash due to possible
1550 		 * overflow from the leaf due to hash collisions.
1551 		 */
1552 		dref = (struct btrfs_extent_data_ref *)ptr;
1553 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1554 		if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1555 			extent_err(leaf, slot,
1556 	"invalid extent data backref offset, have %llu expect aligned to %u",
1557 				   offset, leaf->fs_info->sectorsize);
1558 			return -EUCLEAN;
1559 		}
1560 	}
1561 	return 0;
1562 }
1563 
1564 #define inode_ref_err(eb, slot, fmt, args...)			\
1565 	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)1566 static int check_inode_ref(struct extent_buffer *leaf,
1567 			   struct btrfs_key *key, struct btrfs_key *prev_key,
1568 			   int slot)
1569 {
1570 	struct btrfs_inode_ref *iref;
1571 	unsigned long ptr;
1572 	unsigned long end;
1573 
1574 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1575 		return -EUCLEAN;
1576 	/* namelen can't be 0, so item_size == sizeof() is also invalid */
1577 	if (unlikely(btrfs_item_size(leaf, slot) <= sizeof(*iref))) {
1578 		inode_ref_err(leaf, slot,
1579 			"invalid item size, have %u expect (%zu, %u)",
1580 			btrfs_item_size(leaf, slot),
1581 			sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1582 		return -EUCLEAN;
1583 	}
1584 
1585 	ptr = btrfs_item_ptr_offset(leaf, slot);
1586 	end = ptr + btrfs_item_size(leaf, slot);
1587 	while (ptr < end) {
1588 		u16 namelen;
1589 
1590 		if (unlikely(ptr + sizeof(iref) > end)) {
1591 			inode_ref_err(leaf, slot,
1592 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1593 				ptr, end, sizeof(iref));
1594 			return -EUCLEAN;
1595 		}
1596 
1597 		iref = (struct btrfs_inode_ref *)ptr;
1598 		namelen = btrfs_inode_ref_name_len(leaf, iref);
1599 		if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1600 			inode_ref_err(leaf, slot,
1601 				"inode ref overflow, ptr %lu end %lu namelen %u",
1602 				ptr, end, namelen);
1603 			return -EUCLEAN;
1604 		}
1605 
1606 		/*
1607 		 * NOTE: In theory we should record all found index numbers
1608 		 * to find any duplicated indexes, but that will be too time
1609 		 * consuming for inodes with too many hard links.
1610 		 */
1611 		ptr += sizeof(*iref) + namelen;
1612 	}
1613 	return 0;
1614 }
1615 
1616 /*
1617  * Common point to switch the item-specific validation.
1618  */
check_leaf_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1619 static int check_leaf_item(struct extent_buffer *leaf,
1620 			   struct btrfs_key *key, int slot,
1621 			   struct btrfs_key *prev_key)
1622 {
1623 	int ret = 0;
1624 	struct btrfs_chunk *chunk;
1625 
1626 	switch (key->type) {
1627 	case BTRFS_EXTENT_DATA_KEY:
1628 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1629 		break;
1630 	case BTRFS_EXTENT_CSUM_KEY:
1631 		ret = check_csum_item(leaf, key, slot, prev_key);
1632 		break;
1633 	case BTRFS_DIR_ITEM_KEY:
1634 	case BTRFS_DIR_INDEX_KEY:
1635 	case BTRFS_XATTR_ITEM_KEY:
1636 		ret = check_dir_item(leaf, key, prev_key, slot);
1637 		break;
1638 	case BTRFS_INODE_REF_KEY:
1639 		ret = check_inode_ref(leaf, key, prev_key, slot);
1640 		break;
1641 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1642 		ret = check_block_group_item(leaf, key, slot);
1643 		break;
1644 	case BTRFS_CHUNK_ITEM_KEY:
1645 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1646 		ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1647 		break;
1648 	case BTRFS_DEV_ITEM_KEY:
1649 		ret = check_dev_item(leaf, key, slot);
1650 		break;
1651 	case BTRFS_INODE_ITEM_KEY:
1652 		ret = check_inode_item(leaf, key, slot);
1653 		break;
1654 	case BTRFS_ROOT_ITEM_KEY:
1655 		ret = check_root_item(leaf, key, slot);
1656 		break;
1657 	case BTRFS_EXTENT_ITEM_KEY:
1658 	case BTRFS_METADATA_ITEM_KEY:
1659 		ret = check_extent_item(leaf, key, slot, prev_key);
1660 		break;
1661 	case BTRFS_TREE_BLOCK_REF_KEY:
1662 	case BTRFS_SHARED_DATA_REF_KEY:
1663 	case BTRFS_SHARED_BLOCK_REF_KEY:
1664 		ret = check_simple_keyed_refs(leaf, key, slot);
1665 		break;
1666 	case BTRFS_EXTENT_DATA_REF_KEY:
1667 		ret = check_extent_data_ref(leaf, key, slot);
1668 		break;
1669 	}
1670 	return ret;
1671 }
1672 
check_leaf(struct extent_buffer * leaf,bool check_item_data)1673 static int check_leaf(struct extent_buffer *leaf, bool check_item_data)
1674 {
1675 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1676 	/* No valid key type is 0, so all key should be larger than this key */
1677 	struct btrfs_key prev_key = {0, 0, 0};
1678 	struct btrfs_key key;
1679 	u32 nritems = btrfs_header_nritems(leaf);
1680 	int slot;
1681 
1682 	if (unlikely(btrfs_header_level(leaf) != 0)) {
1683 		generic_err(leaf, 0,
1684 			"invalid level for leaf, have %d expect 0",
1685 			btrfs_header_level(leaf));
1686 		return -EUCLEAN;
1687 	}
1688 
1689 	/*
1690 	 * Extent buffers from a relocation tree have a owner field that
1691 	 * corresponds to the subvolume tree they are based on. So just from an
1692 	 * extent buffer alone we can not find out what is the id of the
1693 	 * corresponding subvolume tree, so we can not figure out if the extent
1694 	 * buffer corresponds to the root of the relocation tree or not. So
1695 	 * skip this check for relocation trees.
1696 	 */
1697 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1698 		u64 owner = btrfs_header_owner(leaf);
1699 
1700 		/* These trees must never be empty */
1701 		if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1702 			     owner == BTRFS_CHUNK_TREE_OBJECTID ||
1703 			     owner == BTRFS_DEV_TREE_OBJECTID ||
1704 			     owner == BTRFS_FS_TREE_OBJECTID ||
1705 			     owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1706 			generic_err(leaf, 0,
1707 			"invalid root, root %llu must never be empty",
1708 				    owner);
1709 			return -EUCLEAN;
1710 		}
1711 
1712 		/* Unknown tree */
1713 		if (unlikely(owner == 0)) {
1714 			generic_err(leaf, 0,
1715 				"invalid owner, root 0 is not defined");
1716 			return -EUCLEAN;
1717 		}
1718 
1719 		/* EXTENT_TREE_V2 can have empty extent trees. */
1720 		if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
1721 			return 0;
1722 
1723 		if (unlikely(owner == BTRFS_EXTENT_TREE_OBJECTID)) {
1724 			generic_err(leaf, 0,
1725 			"invalid root, root %llu must never be empty",
1726 				    owner);
1727 			return -EUCLEAN;
1728 		}
1729 
1730 		return 0;
1731 	}
1732 
1733 	if (unlikely(nritems == 0))
1734 		return 0;
1735 
1736 	/*
1737 	 * Check the following things to make sure this is a good leaf, and
1738 	 * leaf users won't need to bother with similar sanity checks:
1739 	 *
1740 	 * 1) key ordering
1741 	 * 2) item offset and size
1742 	 *    No overlap, no hole, all inside the leaf.
1743 	 * 3) item content
1744 	 *    If possible, do comprehensive sanity check.
1745 	 *    NOTE: All checks must only rely on the item data itself.
1746 	 */
1747 	for (slot = 0; slot < nritems; slot++) {
1748 		u32 item_end_expected;
1749 		u64 item_data_end;
1750 		int ret;
1751 
1752 		btrfs_item_key_to_cpu(leaf, &key, slot);
1753 
1754 		/* Make sure the keys are in the right order */
1755 		if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
1756 			generic_err(leaf, slot,
1757 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1758 				prev_key.objectid, prev_key.type,
1759 				prev_key.offset, key.objectid, key.type,
1760 				key.offset);
1761 			return -EUCLEAN;
1762 		}
1763 
1764 		item_data_end = (u64)btrfs_item_offset(leaf, slot) +
1765 				btrfs_item_size(leaf, slot);
1766 		/*
1767 		 * Make sure the offset and ends are right, remember that the
1768 		 * item data starts at the end of the leaf and grows towards the
1769 		 * front.
1770 		 */
1771 		if (slot == 0)
1772 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1773 		else
1774 			item_end_expected = btrfs_item_offset(leaf,
1775 								 slot - 1);
1776 		if (unlikely(item_data_end != item_end_expected)) {
1777 			generic_err(leaf, slot,
1778 				"unexpected item end, have %llu expect %u",
1779 				item_data_end, item_end_expected);
1780 			return -EUCLEAN;
1781 		}
1782 
1783 		/*
1784 		 * Check to make sure that we don't point outside of the leaf,
1785 		 * just in case all the items are consistent to each other, but
1786 		 * all point outside of the leaf.
1787 		 */
1788 		if (unlikely(item_data_end > BTRFS_LEAF_DATA_SIZE(fs_info))) {
1789 			generic_err(leaf, slot,
1790 			"slot end outside of leaf, have %llu expect range [0, %u]",
1791 				item_data_end, BTRFS_LEAF_DATA_SIZE(fs_info));
1792 			return -EUCLEAN;
1793 		}
1794 
1795 		/* Also check if the item pointer overlaps with btrfs item. */
1796 		if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
1797 			     btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item))) {
1798 			generic_err(leaf, slot,
1799 		"slot overlaps with its data, item end %lu data start %lu",
1800 				btrfs_item_nr_offset(slot) +
1801 				sizeof(struct btrfs_item),
1802 				btrfs_item_ptr_offset(leaf, slot));
1803 			return -EUCLEAN;
1804 		}
1805 
1806 		if (check_item_data) {
1807 			/*
1808 			 * Check if the item size and content meet other
1809 			 * criteria
1810 			 */
1811 			ret = check_leaf_item(leaf, &key, slot, &prev_key);
1812 			if (unlikely(ret < 0))
1813 				return ret;
1814 		}
1815 
1816 		prev_key.objectid = key.objectid;
1817 		prev_key.type = key.type;
1818 		prev_key.offset = key.offset;
1819 	}
1820 
1821 	return 0;
1822 }
1823 
btrfs_check_leaf_full(struct extent_buffer * leaf)1824 int btrfs_check_leaf_full(struct extent_buffer *leaf)
1825 {
1826 	return check_leaf(leaf, true);
1827 }
1828 ALLOW_ERROR_INJECTION(btrfs_check_leaf_full, ERRNO);
1829 
btrfs_check_leaf_relaxed(struct extent_buffer * leaf)1830 int btrfs_check_leaf_relaxed(struct extent_buffer *leaf)
1831 {
1832 	return check_leaf(leaf, false);
1833 }
1834 
btrfs_check_node(struct extent_buffer * node)1835 int btrfs_check_node(struct extent_buffer *node)
1836 {
1837 	struct btrfs_fs_info *fs_info = node->fs_info;
1838 	unsigned long nr = btrfs_header_nritems(node);
1839 	struct btrfs_key key, next_key;
1840 	int slot;
1841 	int level = btrfs_header_level(node);
1842 	u64 bytenr;
1843 	int ret = 0;
1844 
1845 	if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
1846 		generic_err(node, 0,
1847 			"invalid level for node, have %d expect [1, %d]",
1848 			level, BTRFS_MAX_LEVEL - 1);
1849 		return -EUCLEAN;
1850 	}
1851 	if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
1852 		btrfs_crit(fs_info,
1853 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1854 			   btrfs_header_owner(node), node->start,
1855 			   nr == 0 ? "small" : "large", nr,
1856 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1857 		return -EUCLEAN;
1858 	}
1859 
1860 	for (slot = 0; slot < nr - 1; slot++) {
1861 		bytenr = btrfs_node_blockptr(node, slot);
1862 		btrfs_node_key_to_cpu(node, &key, slot);
1863 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1864 
1865 		if (unlikely(!bytenr)) {
1866 			generic_err(node, slot,
1867 				"invalid NULL node pointer");
1868 			ret = -EUCLEAN;
1869 			goto out;
1870 		}
1871 		if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
1872 			generic_err(node, slot,
1873 			"unaligned pointer, have %llu should be aligned to %u",
1874 				bytenr, fs_info->sectorsize);
1875 			ret = -EUCLEAN;
1876 			goto out;
1877 		}
1878 
1879 		if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
1880 			generic_err(node, slot,
1881 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1882 				key.objectid, key.type, key.offset,
1883 				next_key.objectid, next_key.type,
1884 				next_key.offset);
1885 			ret = -EUCLEAN;
1886 			goto out;
1887 		}
1888 	}
1889 out:
1890 	return ret;
1891 }
1892 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
1893 
btrfs_check_eb_owner(const struct extent_buffer * eb,u64 root_owner)1894 int btrfs_check_eb_owner(const struct extent_buffer *eb, u64 root_owner)
1895 {
1896 	const bool is_subvol = is_fstree(root_owner);
1897 	const u64 eb_owner = btrfs_header_owner(eb);
1898 
1899 	/*
1900 	 * Skip dummy fs, as selftests don't create unique ebs for each dummy
1901 	 * root.
1902 	 */
1903 	if (test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &eb->fs_info->fs_state))
1904 		return 0;
1905 	/*
1906 	 * There are several call sites (backref walking, qgroup, and data
1907 	 * reloc) passing 0 as @root_owner, as they are not holding the
1908 	 * tree root.  In that case, we can not do a reliable ownership check,
1909 	 * so just exit.
1910 	 */
1911 	if (root_owner == 0)
1912 		return 0;
1913 	/*
1914 	 * These trees use key.offset as their owner, our callers don't have
1915 	 * the extra capacity to pass key.offset here.  So we just skip them.
1916 	 */
1917 	if (root_owner == BTRFS_TREE_LOG_OBJECTID ||
1918 	    root_owner == BTRFS_TREE_RELOC_OBJECTID)
1919 		return 0;
1920 
1921 	if (!is_subvol) {
1922 		/* For non-subvolume trees, the eb owner should match root owner */
1923 		if (unlikely(root_owner != eb_owner)) {
1924 			btrfs_crit(eb->fs_info,
1925 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect %llu",
1926 				btrfs_header_level(eb) == 0 ? "leaf" : "node",
1927 				root_owner, btrfs_header_bytenr(eb), eb_owner,
1928 				root_owner);
1929 			return -EUCLEAN;
1930 		}
1931 		return 0;
1932 	}
1933 
1934 	/*
1935 	 * For subvolume trees, owners can mismatch, but they should all belong
1936 	 * to subvolume trees.
1937 	 */
1938 	if (unlikely(is_subvol != is_fstree(eb_owner))) {
1939 		btrfs_crit(eb->fs_info,
1940 "corrupted %s, root=%llu block=%llu owner mismatch, have %llu expect [%llu, %llu]",
1941 			btrfs_header_level(eb) == 0 ? "leaf" : "node",
1942 			root_owner, btrfs_header_bytenr(eb), eb_owner,
1943 			BTRFS_FIRST_FREE_OBJECTID, BTRFS_LAST_FREE_OBJECTID);
1944 		return -EUCLEAN;
1945 	}
1946 	return 0;
1947 }
1948