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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) Qu Wenruo 2017.  All rights reserved.
4  */
5 
6 /*
7  * The module is used to catch unexpected/corrupted tree block data.
8  * Such behavior can be caused either by a fuzzed image or bugs.
9  *
10  * The objective is to do leaf/node validation checks when tree block is read
11  * from disk, and check *every* possible member, so other code won't
12  * need to checking them again.
13  *
14  * Due to the potential and unwanted damage, every checker needs to be
15  * carefully reviewed otherwise so it does not prevent mount of valid images.
16  */
17 
18 #include <linux/types.h>
19 #include <linux/stddef.h>
20 #include <linux/error-injection.h>
21 #include "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_nr(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_nr(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_nr(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_nr(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_nr(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_block_group_item bgi;
657 	u32 item_size = btrfs_item_size_nr(leaf, slot);
658 	u64 flags;
659 	u64 type;
660 
661 	/*
662 	 * Here we don't really care about alignment since extent allocator can
663 	 * handle it.  We care more about the size.
664 	 */
665 	if (unlikely(key->offset == 0)) {
666 		block_group_err(leaf, slot,
667 				"invalid block group size 0");
668 		return -EUCLEAN;
669 	}
670 
671 	if (unlikely(item_size != sizeof(bgi))) {
672 		block_group_err(leaf, slot,
673 			"invalid item size, have %u expect %zu",
674 				item_size, sizeof(bgi));
675 		return -EUCLEAN;
676 	}
677 
678 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
679 			   sizeof(bgi));
680 	if (unlikely(btrfs_stack_block_group_chunk_objectid(&bgi) !=
681 		     BTRFS_FIRST_CHUNK_TREE_OBJECTID)) {
682 		block_group_err(leaf, slot,
683 		"invalid block group chunk objectid, have %llu expect %llu",
684 				btrfs_stack_block_group_chunk_objectid(&bgi),
685 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
686 		return -EUCLEAN;
687 	}
688 
689 	if (unlikely(btrfs_stack_block_group_used(&bgi) > key->offset)) {
690 		block_group_err(leaf, slot,
691 			"invalid block group used, have %llu expect [0, %llu)",
692 				btrfs_stack_block_group_used(&bgi), key->offset);
693 		return -EUCLEAN;
694 	}
695 
696 	flags = btrfs_stack_block_group_flags(&bgi);
697 	if (unlikely(hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1)) {
698 		block_group_err(leaf, slot,
699 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
700 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
701 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
702 		return -EUCLEAN;
703 	}
704 
705 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
706 	if (unlikely(type != BTRFS_BLOCK_GROUP_DATA &&
707 		     type != BTRFS_BLOCK_GROUP_METADATA &&
708 		     type != BTRFS_BLOCK_GROUP_SYSTEM &&
709 		     type != (BTRFS_BLOCK_GROUP_METADATA |
710 			      BTRFS_BLOCK_GROUP_DATA))) {
711 		block_group_err(leaf, slot,
712 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
713 			type, hweight64(type),
714 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
715 			BTRFS_BLOCK_GROUP_SYSTEM,
716 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
717 		return -EUCLEAN;
718 	}
719 	return 0;
720 }
721 
722 __printf(4, 5)
723 __cold
chunk_err(const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,const char * fmt,...)724 static void chunk_err(const struct extent_buffer *leaf,
725 		      const struct btrfs_chunk *chunk, u64 logical,
726 		      const char *fmt, ...)
727 {
728 	const struct btrfs_fs_info *fs_info = leaf->fs_info;
729 	bool is_sb;
730 	struct va_format vaf;
731 	va_list args;
732 	int i;
733 	int slot = -1;
734 
735 	/* Only superblock eb is able to have such small offset */
736 	is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
737 
738 	if (!is_sb) {
739 		/*
740 		 * Get the slot number by iterating through all slots, this
741 		 * would provide better readability.
742 		 */
743 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
744 			if (btrfs_item_ptr_offset(leaf, i) ==
745 					(unsigned long)chunk) {
746 				slot = i;
747 				break;
748 			}
749 		}
750 	}
751 	va_start(args, fmt);
752 	vaf.fmt = fmt;
753 	vaf.va = &args;
754 
755 	if (is_sb)
756 		btrfs_crit(fs_info,
757 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
758 			   logical, &vaf);
759 	else
760 		btrfs_crit(fs_info,
761 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
762 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
763 			   logical, &vaf);
764 	va_end(args);
765 }
766 
767 /*
768  * The common chunk check which could also work on super block sys chunk array.
769  *
770  * Return -EUCLEAN if anything is corrupted.
771  * Return 0 if everything is OK.
772  */
btrfs_check_chunk_valid(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 logical)773 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
774 			    struct btrfs_chunk *chunk, u64 logical)
775 {
776 	struct btrfs_fs_info *fs_info = leaf->fs_info;
777 	u64 length;
778 	u64 chunk_end;
779 	u64 stripe_len;
780 	u16 num_stripes;
781 	u16 sub_stripes;
782 	u64 type;
783 	u64 features;
784 	bool mixed = false;
785 	int raid_index;
786 	int nparity;
787 	int ncopies;
788 
789 	length = btrfs_chunk_length(leaf, chunk);
790 	stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
791 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
792 	sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
793 	type = btrfs_chunk_type(leaf, chunk);
794 	raid_index = btrfs_bg_flags_to_raid_index(type);
795 	ncopies = btrfs_raid_array[raid_index].ncopies;
796 	nparity = btrfs_raid_array[raid_index].nparity;
797 
798 	if (unlikely(!num_stripes)) {
799 		chunk_err(leaf, chunk, logical,
800 			  "invalid chunk num_stripes, have %u", num_stripes);
801 		return -EUCLEAN;
802 	}
803 	if (unlikely(num_stripes < ncopies)) {
804 		chunk_err(leaf, chunk, logical,
805 			  "invalid chunk num_stripes < ncopies, have %u < %d",
806 			  num_stripes, ncopies);
807 		return -EUCLEAN;
808 	}
809 	if (unlikely(nparity && num_stripes == nparity)) {
810 		chunk_err(leaf, chunk, logical,
811 			  "invalid chunk num_stripes == nparity, have %u == %d",
812 			  num_stripes, nparity);
813 		return -EUCLEAN;
814 	}
815 	if (unlikely(!IS_ALIGNED(logical, fs_info->sectorsize))) {
816 		chunk_err(leaf, chunk, logical,
817 		"invalid chunk logical, have %llu should aligned to %u",
818 			  logical, fs_info->sectorsize);
819 		return -EUCLEAN;
820 	}
821 	if (unlikely(btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize)) {
822 		chunk_err(leaf, chunk, logical,
823 			  "invalid chunk sectorsize, have %u expect %u",
824 			  btrfs_chunk_sector_size(leaf, chunk),
825 			  fs_info->sectorsize);
826 		return -EUCLEAN;
827 	}
828 	if (unlikely(!length || !IS_ALIGNED(length, fs_info->sectorsize))) {
829 		chunk_err(leaf, chunk, logical,
830 			  "invalid chunk length, have %llu", length);
831 		return -EUCLEAN;
832 	}
833 	if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
834 		chunk_err(leaf, chunk, logical,
835 "invalid chunk logical start and length, have logical start %llu length %llu",
836 			  logical, length);
837 		return -EUCLEAN;
838 	}
839 	if (unlikely(!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN)) {
840 		chunk_err(leaf, chunk, logical,
841 			  "invalid chunk stripe length: %llu",
842 			  stripe_len);
843 		return -EUCLEAN;
844 	}
845 	if (unlikely(type & ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
846 			      BTRFS_BLOCK_GROUP_PROFILE_MASK))) {
847 		chunk_err(leaf, chunk, logical,
848 			  "unrecognized chunk type: 0x%llx",
849 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
850 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) &
851 			  btrfs_chunk_type(leaf, chunk));
852 		return -EUCLEAN;
853 	}
854 
855 	if (unlikely(!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
856 		     (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0)) {
857 		chunk_err(leaf, chunk, logical,
858 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
859 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
860 		return -EUCLEAN;
861 	}
862 	if (unlikely((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0)) {
863 		chunk_err(leaf, chunk, logical,
864 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
865 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
866 		return -EUCLEAN;
867 	}
868 
869 	if (unlikely((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
870 		     (type & (BTRFS_BLOCK_GROUP_METADATA |
871 			      BTRFS_BLOCK_GROUP_DATA)))) {
872 		chunk_err(leaf, chunk, logical,
873 			  "system chunk with data or metadata type: 0x%llx",
874 			  type);
875 		return -EUCLEAN;
876 	}
877 
878 	features = btrfs_super_incompat_flags(fs_info->super_copy);
879 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
880 		mixed = true;
881 
882 	if (!mixed) {
883 		if (unlikely((type & BTRFS_BLOCK_GROUP_METADATA) &&
884 			     (type & BTRFS_BLOCK_GROUP_DATA))) {
885 			chunk_err(leaf, chunk, logical,
886 			"mixed chunk type in non-mixed mode: 0x%llx", type);
887 			return -EUCLEAN;
888 		}
889 	}
890 
891 	if (unlikely((type & BTRFS_BLOCK_GROUP_RAID10 &&
892 		      sub_stripes != btrfs_raid_array[BTRFS_RAID_RAID10].sub_stripes) ||
893 		     (type & BTRFS_BLOCK_GROUP_RAID1 &&
894 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1].devs_min) ||
895 		     (type & BTRFS_BLOCK_GROUP_RAID1C3 &&
896 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C3].devs_min) ||
897 		     (type & BTRFS_BLOCK_GROUP_RAID1C4 &&
898 		      num_stripes != btrfs_raid_array[BTRFS_RAID_RAID1C4].devs_min) ||
899 		     (type & BTRFS_BLOCK_GROUP_RAID5 &&
900 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID5].devs_min) ||
901 		     (type & BTRFS_BLOCK_GROUP_RAID6 &&
902 		      num_stripes < btrfs_raid_array[BTRFS_RAID_RAID6].devs_min) ||
903 		     (type & BTRFS_BLOCK_GROUP_DUP &&
904 		      num_stripes != btrfs_raid_array[BTRFS_RAID_DUP].dev_stripes) ||
905 		     ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
906 		      num_stripes != btrfs_raid_array[BTRFS_RAID_SINGLE].dev_stripes))) {
907 		chunk_err(leaf, chunk, logical,
908 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
909 			num_stripes, sub_stripes,
910 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
911 		return -EUCLEAN;
912 	}
913 
914 	return 0;
915 }
916 
917 /*
918  * Enhanced version of chunk item checker.
919  *
920  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
921  * to work on super block sys_chunk_array which doesn't have full item ptr.
922  */
check_leaf_chunk_item(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_key * key,int slot)923 static int check_leaf_chunk_item(struct extent_buffer *leaf,
924 				 struct btrfs_chunk *chunk,
925 				 struct btrfs_key *key, int slot)
926 {
927 	int num_stripes;
928 
929 	if (unlikely(btrfs_item_size_nr(leaf, slot) < sizeof(struct btrfs_chunk))) {
930 		chunk_err(leaf, chunk, key->offset,
931 			"invalid chunk item size: have %u expect [%zu, %u)",
932 			btrfs_item_size_nr(leaf, slot),
933 			sizeof(struct btrfs_chunk),
934 			BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
935 		return -EUCLEAN;
936 	}
937 
938 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
939 	/* Let btrfs_check_chunk_valid() handle this error type */
940 	if (num_stripes == 0)
941 		goto out;
942 
943 	if (unlikely(btrfs_chunk_item_size(num_stripes) !=
944 		     btrfs_item_size_nr(leaf, slot))) {
945 		chunk_err(leaf, chunk, key->offset,
946 			"invalid chunk item size: have %u expect %lu",
947 			btrfs_item_size_nr(leaf, slot),
948 			btrfs_chunk_item_size(num_stripes));
949 		return -EUCLEAN;
950 	}
951 out:
952 	return btrfs_check_chunk_valid(leaf, chunk, key->offset);
953 }
954 
955 __printf(3, 4)
956 __cold
dev_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)957 static void dev_item_err(const struct extent_buffer *eb, int slot,
958 			 const char *fmt, ...)
959 {
960 	struct btrfs_key key;
961 	struct va_format vaf;
962 	va_list args;
963 
964 	btrfs_item_key_to_cpu(eb, &key, slot);
965 	va_start(args, fmt);
966 
967 	vaf.fmt = fmt;
968 	vaf.va = &args;
969 
970 	btrfs_crit(eb->fs_info,
971 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
972 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
973 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
974 		key.objectid, &vaf);
975 	va_end(args);
976 }
977 
check_dev_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)978 static int check_dev_item(struct extent_buffer *leaf,
979 			  struct btrfs_key *key, int slot)
980 {
981 	struct btrfs_dev_item *ditem;
982 	const u32 item_size = btrfs_item_size_nr(leaf, slot);
983 
984 	if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
985 		dev_item_err(leaf, slot,
986 			     "invalid objectid: has=%llu expect=%llu",
987 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
988 		return -EUCLEAN;
989 	}
990 
991 	if (unlikely(item_size != sizeof(*ditem))) {
992 		dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
993 			     item_size, sizeof(*ditem));
994 		return -EUCLEAN;
995 	}
996 
997 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
998 	if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
999 		dev_item_err(leaf, slot,
1000 			     "devid mismatch: key has=%llu item has=%llu",
1001 			     key->offset, btrfs_device_id(leaf, ditem));
1002 		return -EUCLEAN;
1003 	}
1004 
1005 	/*
1006 	 * For device total_bytes, we don't have reliable way to check it, as
1007 	 * it can be 0 for device removal. Device size check can only be done
1008 	 * by dev extents check.
1009 	 */
1010 	if (unlikely(btrfs_device_bytes_used(leaf, ditem) >
1011 		     btrfs_device_total_bytes(leaf, ditem))) {
1012 		dev_item_err(leaf, slot,
1013 			     "invalid bytes used: have %llu expect [0, %llu]",
1014 			     btrfs_device_bytes_used(leaf, ditem),
1015 			     btrfs_device_total_bytes(leaf, ditem));
1016 		return -EUCLEAN;
1017 	}
1018 	/*
1019 	 * Remaining members like io_align/type/gen/dev_group aren't really
1020 	 * utilized.  Skip them to make later usage of them easier.
1021 	 */
1022 	return 0;
1023 }
1024 
check_inode_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1025 static int check_inode_item(struct extent_buffer *leaf,
1026 			    struct btrfs_key *key, int slot)
1027 {
1028 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1029 	struct btrfs_inode_item *iitem;
1030 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
1031 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
1032 	const u32 item_size = btrfs_item_size_nr(leaf, slot);
1033 	u32 mode;
1034 	int ret;
1035 	u32 flags;
1036 	u32 ro_flags;
1037 
1038 	ret = check_inode_key(leaf, key, slot);
1039 	if (unlikely(ret < 0))
1040 		return ret;
1041 
1042 	if (unlikely(item_size != sizeof(*iitem))) {
1043 		generic_err(leaf, slot, "invalid item size: has %u expect %zu",
1044 			    item_size, sizeof(*iitem));
1045 		return -EUCLEAN;
1046 	}
1047 
1048 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
1049 
1050 	/* Here we use super block generation + 1 to handle log tree */
1051 	if (unlikely(btrfs_inode_generation(leaf, iitem) > super_gen + 1)) {
1052 		inode_item_err(leaf, slot,
1053 			"invalid inode generation: has %llu expect (0, %llu]",
1054 			       btrfs_inode_generation(leaf, iitem),
1055 			       super_gen + 1);
1056 		return -EUCLEAN;
1057 	}
1058 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
1059 	if (unlikely(btrfs_inode_transid(leaf, iitem) > super_gen + 1)) {
1060 		inode_item_err(leaf, slot,
1061 			"invalid inode transid: has %llu expect [0, %llu]",
1062 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
1063 		return -EUCLEAN;
1064 	}
1065 
1066 	/*
1067 	 * For size and nbytes it's better not to be too strict, as for dir
1068 	 * item its size/nbytes can easily get wrong, but doesn't affect
1069 	 * anything in the fs. So here we skip the check.
1070 	 */
1071 	mode = btrfs_inode_mode(leaf, iitem);
1072 	if (unlikely(mode & ~valid_mask)) {
1073 		inode_item_err(leaf, slot,
1074 			       "unknown mode bit detected: 0x%x",
1075 			       mode & ~valid_mask);
1076 		return -EUCLEAN;
1077 	}
1078 
1079 	/*
1080 	 * S_IFMT is not bit mapped so we can't completely rely on
1081 	 * is_power_of_2/has_single_bit_set, but it can save us from checking
1082 	 * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
1083 	 */
1084 	if (!has_single_bit_set(mode & S_IFMT)) {
1085 		if (unlikely(!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode))) {
1086 			inode_item_err(leaf, slot,
1087 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
1088 				       mode & S_IFMT);
1089 			return -EUCLEAN;
1090 		}
1091 	}
1092 	if (unlikely(S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1)) {
1093 		inode_item_err(leaf, slot,
1094 		       "invalid nlink: has %u expect no more than 1 for dir",
1095 			btrfs_inode_nlink(leaf, iitem));
1096 		return -EUCLEAN;
1097 	}
1098 	btrfs_inode_split_flags(btrfs_inode_flags(leaf, iitem), &flags, &ro_flags);
1099 	if (unlikely(flags & ~BTRFS_INODE_FLAG_MASK)) {
1100 		inode_item_err(leaf, slot,
1101 			       "unknown incompat flags detected: 0x%x", flags);
1102 		return -EUCLEAN;
1103 	}
1104 	if (unlikely(!sb_rdonly(fs_info->sb) &&
1105 		     (ro_flags & ~BTRFS_INODE_RO_FLAG_MASK))) {
1106 		inode_item_err(leaf, slot,
1107 			"unknown ro-compat flags detected on writeable mount: 0x%x",
1108 			ro_flags);
1109 		return -EUCLEAN;
1110 	}
1111 	return 0;
1112 }
1113 
check_root_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1114 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
1115 			   int slot)
1116 {
1117 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1118 	struct btrfs_root_item ri = { 0 };
1119 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
1120 				     BTRFS_ROOT_SUBVOL_DEAD;
1121 	int ret;
1122 
1123 	ret = check_root_key(leaf, key, slot);
1124 	if (unlikely(ret < 0))
1125 		return ret;
1126 
1127 	if (unlikely(btrfs_item_size_nr(leaf, slot) != sizeof(ri) &&
1128 		     btrfs_item_size_nr(leaf, slot) !=
1129 		     btrfs_legacy_root_item_size())) {
1130 		generic_err(leaf, slot,
1131 			    "invalid root item size, have %u expect %zu or %u",
1132 			    btrfs_item_size_nr(leaf, slot), sizeof(ri),
1133 			    btrfs_legacy_root_item_size());
1134 		return -EUCLEAN;
1135 	}
1136 
1137 	/*
1138 	 * For legacy root item, the members starting at generation_v2 will be
1139 	 * all filled with 0.
1140 	 * And since we allow geneartion_v2 as 0, it will still pass the check.
1141 	 */
1142 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
1143 			   btrfs_item_size_nr(leaf, slot));
1144 
1145 	/* Generation related */
1146 	if (unlikely(btrfs_root_generation(&ri) >
1147 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1148 		generic_err(leaf, slot,
1149 			"invalid root generation, have %llu expect (0, %llu]",
1150 			    btrfs_root_generation(&ri),
1151 			    btrfs_super_generation(fs_info->super_copy) + 1);
1152 		return -EUCLEAN;
1153 	}
1154 	if (unlikely(btrfs_root_generation_v2(&ri) >
1155 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1156 		generic_err(leaf, slot,
1157 		"invalid root v2 generation, have %llu expect (0, %llu]",
1158 			    btrfs_root_generation_v2(&ri),
1159 			    btrfs_super_generation(fs_info->super_copy) + 1);
1160 		return -EUCLEAN;
1161 	}
1162 	if (unlikely(btrfs_root_last_snapshot(&ri) >
1163 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1164 		generic_err(leaf, slot,
1165 		"invalid root last_snapshot, have %llu expect (0, %llu]",
1166 			    btrfs_root_last_snapshot(&ri),
1167 			    btrfs_super_generation(fs_info->super_copy) + 1);
1168 		return -EUCLEAN;
1169 	}
1170 
1171 	/* Alignment and level check */
1172 	if (unlikely(!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize))) {
1173 		generic_err(leaf, slot,
1174 		"invalid root bytenr, have %llu expect to be aligned to %u",
1175 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
1176 		return -EUCLEAN;
1177 	}
1178 	if (unlikely(btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL)) {
1179 		generic_err(leaf, slot,
1180 			    "invalid root level, have %u expect [0, %u]",
1181 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
1182 		return -EUCLEAN;
1183 	}
1184 	if (unlikely(btrfs_root_drop_level(&ri) >= BTRFS_MAX_LEVEL)) {
1185 		generic_err(leaf, slot,
1186 			    "invalid root level, have %u expect [0, %u]",
1187 			    btrfs_root_drop_level(&ri), BTRFS_MAX_LEVEL - 1);
1188 		return -EUCLEAN;
1189 	}
1190 
1191 	/* Flags check */
1192 	if (unlikely(btrfs_root_flags(&ri) & ~valid_root_flags)) {
1193 		generic_err(leaf, slot,
1194 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
1195 			    btrfs_root_flags(&ri), valid_root_flags);
1196 		return -EUCLEAN;
1197 	}
1198 	return 0;
1199 }
1200 
1201 __printf(3,4)
1202 __cold
extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)1203 static void extent_err(const struct extent_buffer *eb, int slot,
1204 		       const char *fmt, ...)
1205 {
1206 	struct btrfs_key key;
1207 	struct va_format vaf;
1208 	va_list args;
1209 	u64 bytenr;
1210 	u64 len;
1211 
1212 	btrfs_item_key_to_cpu(eb, &key, slot);
1213 	bytenr = key.objectid;
1214 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
1215 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1216 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1217 		len = eb->fs_info->nodesize;
1218 	else
1219 		len = key.offset;
1220 	va_start(args, fmt);
1221 
1222 	vaf.fmt = fmt;
1223 	vaf.va = &args;
1224 
1225 	btrfs_crit(eb->fs_info,
1226 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1227 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1228 		eb->start, slot, bytenr, len, &vaf);
1229 	va_end(args);
1230 }
1231 
check_extent_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1232 static int check_extent_item(struct extent_buffer *leaf,
1233 			     struct btrfs_key *key, int slot,
1234 			     struct btrfs_key *prev_key)
1235 {
1236 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1237 	struct btrfs_extent_item *ei;
1238 	bool is_tree_block = false;
1239 	unsigned long ptr;	/* Current pointer inside inline refs */
1240 	unsigned long end;	/* Extent item end */
1241 	const u32 item_size = btrfs_item_size_nr(leaf, slot);
1242 	u64 flags;
1243 	u64 generation;
1244 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1245 	u64 inline_refs = 0;	/* found total inline refs */
1246 
1247 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1248 		     !btrfs_fs_incompat(fs_info, SKINNY_METADATA))) {
1249 		generic_err(leaf, slot,
1250 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1251 		return -EUCLEAN;
1252 	}
1253 	/* key->objectid is the bytenr for both key types */
1254 	if (unlikely(!IS_ALIGNED(key->objectid, fs_info->sectorsize))) {
1255 		generic_err(leaf, slot,
1256 		"invalid key objectid, have %llu expect to be aligned to %u",
1257 			   key->objectid, fs_info->sectorsize);
1258 		return -EUCLEAN;
1259 	}
1260 
1261 	/* key->offset is tree level for METADATA_ITEM_KEY */
1262 	if (unlikely(key->type == BTRFS_METADATA_ITEM_KEY &&
1263 		     key->offset >= BTRFS_MAX_LEVEL)) {
1264 		extent_err(leaf, slot,
1265 			   "invalid tree level, have %llu expect [0, %u]",
1266 			   key->offset, BTRFS_MAX_LEVEL - 1);
1267 		return -EUCLEAN;
1268 	}
1269 
1270 	/*
1271 	 * EXTENT/METADATA_ITEM consists of:
1272 	 * 1) One btrfs_extent_item
1273 	 *    Records the total refs, type and generation of the extent.
1274 	 *
1275 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1276 	 *    Records the first key and level of the tree block.
1277 	 *
1278 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1279 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1280 	 *    2.1) The ref type, one of the 4
1281 	 *         TREE_BLOCK_REF	Tree block only
1282 	 *         SHARED_BLOCK_REF	Tree block only
1283 	 *         EXTENT_DATA_REF	Data only
1284 	 *         SHARED_DATA_REF	Data only
1285 	 *    2.2) Ref type specific data
1286 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1287 	 *         data structure.
1288 	 */
1289 	if (unlikely(item_size < sizeof(*ei))) {
1290 		extent_err(leaf, slot,
1291 			   "invalid item size, have %u expect [%zu, %u)",
1292 			   item_size, sizeof(*ei),
1293 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1294 		return -EUCLEAN;
1295 	}
1296 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1297 
1298 	/* Checks against extent_item */
1299 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1300 	flags = btrfs_extent_flags(leaf, ei);
1301 	total_refs = btrfs_extent_refs(leaf, ei);
1302 	generation = btrfs_extent_generation(leaf, ei);
1303 	if (unlikely(generation >
1304 		     btrfs_super_generation(fs_info->super_copy) + 1)) {
1305 		extent_err(leaf, slot,
1306 			   "invalid generation, have %llu expect (0, %llu]",
1307 			   generation,
1308 			   btrfs_super_generation(fs_info->super_copy) + 1);
1309 		return -EUCLEAN;
1310 	}
1311 	if (unlikely(!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1312 						  BTRFS_EXTENT_FLAG_TREE_BLOCK)))) {
1313 		extent_err(leaf, slot,
1314 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1315 			flags, BTRFS_EXTENT_FLAG_DATA |
1316 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1317 		return -EUCLEAN;
1318 	}
1319 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1320 	if (is_tree_block) {
1321 		if (unlikely(key->type == BTRFS_EXTENT_ITEM_KEY &&
1322 			     key->offset != fs_info->nodesize)) {
1323 			extent_err(leaf, slot,
1324 				   "invalid extent length, have %llu expect %u",
1325 				   key->offset, fs_info->nodesize);
1326 			return -EUCLEAN;
1327 		}
1328 	} else {
1329 		if (unlikely(key->type != BTRFS_EXTENT_ITEM_KEY)) {
1330 			extent_err(leaf, slot,
1331 			"invalid key type, have %u expect %u for data backref",
1332 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1333 			return -EUCLEAN;
1334 		}
1335 		if (unlikely(!IS_ALIGNED(key->offset, fs_info->sectorsize))) {
1336 			extent_err(leaf, slot,
1337 			"invalid extent length, have %llu expect aligned to %u",
1338 				   key->offset, fs_info->sectorsize);
1339 			return -EUCLEAN;
1340 		}
1341 		if (unlikely(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
1342 			extent_err(leaf, slot,
1343 			"invalid extent flag, data has full backref set");
1344 			return -EUCLEAN;
1345 		}
1346 	}
1347 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1348 
1349 	/* Check the special case of btrfs_tree_block_info */
1350 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1351 		struct btrfs_tree_block_info *info;
1352 
1353 		info = (struct btrfs_tree_block_info *)ptr;
1354 		if (unlikely(btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL)) {
1355 			extent_err(leaf, slot,
1356 			"invalid tree block info level, have %u expect [0, %u]",
1357 				   btrfs_tree_block_level(leaf, info),
1358 				   BTRFS_MAX_LEVEL - 1);
1359 			return -EUCLEAN;
1360 		}
1361 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1362 	}
1363 
1364 	/* Check inline refs */
1365 	while (ptr < end) {
1366 		struct btrfs_extent_inline_ref *iref;
1367 		struct btrfs_extent_data_ref *dref;
1368 		struct btrfs_shared_data_ref *sref;
1369 		u64 dref_offset;
1370 		u64 inline_offset;
1371 		u8 inline_type;
1372 
1373 		if (unlikely(ptr + sizeof(*iref) > end)) {
1374 			extent_err(leaf, slot,
1375 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1376 				   ptr, sizeof(*iref), end);
1377 			return -EUCLEAN;
1378 		}
1379 		iref = (struct btrfs_extent_inline_ref *)ptr;
1380 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1381 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1382 		if (unlikely(ptr + btrfs_extent_inline_ref_size(inline_type) > end)) {
1383 			extent_err(leaf, slot,
1384 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1385 				   ptr, btrfs_extent_inline_ref_size(inline_type), end);
1386 			return -EUCLEAN;
1387 		}
1388 
1389 		switch (inline_type) {
1390 		/* inline_offset is subvolid of the owner, no need to check */
1391 		case BTRFS_TREE_BLOCK_REF_KEY:
1392 			inline_refs++;
1393 			break;
1394 		/* Contains parent bytenr */
1395 		case BTRFS_SHARED_BLOCK_REF_KEY:
1396 			if (unlikely(!IS_ALIGNED(inline_offset,
1397 						 fs_info->sectorsize))) {
1398 				extent_err(leaf, slot,
1399 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1400 					   inline_offset, fs_info->sectorsize);
1401 				return -EUCLEAN;
1402 			}
1403 			inline_refs++;
1404 			break;
1405 		/*
1406 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1407 		 * The only obvious corruption can happen in that offset.
1408 		 */
1409 		case BTRFS_EXTENT_DATA_REF_KEY:
1410 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1411 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1412 			if (unlikely(!IS_ALIGNED(dref_offset,
1413 						 fs_info->sectorsize))) {
1414 				extent_err(leaf, slot,
1415 		"invalid data ref offset, have %llu expect aligned to %u",
1416 					   dref_offset, fs_info->sectorsize);
1417 				return -EUCLEAN;
1418 			}
1419 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1420 			break;
1421 		/* Contains parent bytenr and ref count */
1422 		case BTRFS_SHARED_DATA_REF_KEY:
1423 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1424 			if (unlikely(!IS_ALIGNED(inline_offset,
1425 						 fs_info->sectorsize))) {
1426 				extent_err(leaf, slot,
1427 		"invalid data parent bytenr, have %llu expect aligned to %u",
1428 					   inline_offset, fs_info->sectorsize);
1429 				return -EUCLEAN;
1430 			}
1431 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1432 			break;
1433 		default:
1434 			extent_err(leaf, slot, "unknown inline ref type: %u",
1435 				   inline_type);
1436 			return -EUCLEAN;
1437 		}
1438 		ptr += btrfs_extent_inline_ref_size(inline_type);
1439 	}
1440 	/* No padding is allowed */
1441 	if (unlikely(ptr != end)) {
1442 		extent_err(leaf, slot,
1443 			   "invalid extent item size, padding bytes found");
1444 		return -EUCLEAN;
1445 	}
1446 
1447 	/* Finally, check the inline refs against total refs */
1448 	if (unlikely(inline_refs > total_refs)) {
1449 		extent_err(leaf, slot,
1450 			"invalid extent refs, have %llu expect >= inline %llu",
1451 			   total_refs, inline_refs);
1452 		return -EUCLEAN;
1453 	}
1454 
1455 	if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1456 	    (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1457 		u64 prev_end = prev_key->objectid;
1458 
1459 		if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1460 			prev_end += fs_info->nodesize;
1461 		else
1462 			prev_end += prev_key->offset;
1463 
1464 		if (unlikely(prev_end > key->objectid)) {
1465 			extent_err(leaf, slot,
1466 	"previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1467 				   prev_key->objectid, prev_key->type,
1468 				   prev_key->offset, key->objectid, key->type,
1469 				   key->offset);
1470 			return -EUCLEAN;
1471 		}
1472 	}
1473 
1474 	return 0;
1475 }
1476 
check_simple_keyed_refs(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1477 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1478 				   struct btrfs_key *key, int slot)
1479 {
1480 	u32 expect_item_size = 0;
1481 
1482 	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1483 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1484 
1485 	if (unlikely(btrfs_item_size_nr(leaf, slot) != expect_item_size)) {
1486 		generic_err(leaf, slot,
1487 		"invalid item size, have %u expect %u for key type %u",
1488 			    btrfs_item_size_nr(leaf, slot),
1489 			    expect_item_size, key->type);
1490 		return -EUCLEAN;
1491 	}
1492 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1493 		generic_err(leaf, slot,
1494 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1495 			    key->objectid, leaf->fs_info->sectorsize);
1496 		return -EUCLEAN;
1497 	}
1498 	if (unlikely(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1499 		     !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize))) {
1500 		extent_err(leaf, slot,
1501 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1502 			   key->offset, leaf->fs_info->sectorsize);
1503 		return -EUCLEAN;
1504 	}
1505 	return 0;
1506 }
1507 
check_extent_data_ref(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1508 static int check_extent_data_ref(struct extent_buffer *leaf,
1509 				 struct btrfs_key *key, int slot)
1510 {
1511 	struct btrfs_extent_data_ref *dref;
1512 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1513 	const unsigned long end = ptr + btrfs_item_size_nr(leaf, slot);
1514 
1515 	if (unlikely(btrfs_item_size_nr(leaf, slot) % sizeof(*dref) != 0)) {
1516 		generic_err(leaf, slot,
1517 	"invalid item size, have %u expect aligned to %zu for key type %u",
1518 			    btrfs_item_size_nr(leaf, slot),
1519 			    sizeof(*dref), key->type);
1520 		return -EUCLEAN;
1521 	}
1522 	if (unlikely(!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize))) {
1523 		generic_err(leaf, slot,
1524 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1525 			    key->objectid, leaf->fs_info->sectorsize);
1526 		return -EUCLEAN;
1527 	}
1528 	for (; ptr < end; ptr += sizeof(*dref)) {
1529 		u64 offset;
1530 
1531 		/*
1532 		 * We cannot check the extent_data_ref hash due to possible
1533 		 * overflow from the leaf due to hash collisions.
1534 		 */
1535 		dref = (struct btrfs_extent_data_ref *)ptr;
1536 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1537 		if (unlikely(!IS_ALIGNED(offset, leaf->fs_info->sectorsize))) {
1538 			extent_err(leaf, slot,
1539 	"invalid extent data backref offset, have %llu expect aligned to %u",
1540 				   offset, leaf->fs_info->sectorsize);
1541 			return -EUCLEAN;
1542 		}
1543 	}
1544 	return 0;
1545 }
1546 
1547 #define inode_ref_err(eb, slot, fmt, args...)			\
1548 	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)1549 static int check_inode_ref(struct extent_buffer *leaf,
1550 			   struct btrfs_key *key, struct btrfs_key *prev_key,
1551 			   int slot)
1552 {
1553 	struct btrfs_inode_ref *iref;
1554 	unsigned long ptr;
1555 	unsigned long end;
1556 
1557 	if (unlikely(!check_prev_ino(leaf, key, slot, prev_key)))
1558 		return -EUCLEAN;
1559 	/* namelen can't be 0, so item_size == sizeof() is also invalid */
1560 	if (unlikely(btrfs_item_size_nr(leaf, slot) <= sizeof(*iref))) {
1561 		inode_ref_err(leaf, slot,
1562 			"invalid item size, have %u expect (%zu, %u)",
1563 			btrfs_item_size_nr(leaf, slot),
1564 			sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1565 		return -EUCLEAN;
1566 	}
1567 
1568 	ptr = btrfs_item_ptr_offset(leaf, slot);
1569 	end = ptr + btrfs_item_size_nr(leaf, slot);
1570 	while (ptr < end) {
1571 		u16 namelen;
1572 
1573 		if (unlikely(ptr + sizeof(iref) > end)) {
1574 			inode_ref_err(leaf, slot,
1575 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1576 				ptr, end, sizeof(iref));
1577 			return -EUCLEAN;
1578 		}
1579 
1580 		iref = (struct btrfs_inode_ref *)ptr;
1581 		namelen = btrfs_inode_ref_name_len(leaf, iref);
1582 		if (unlikely(ptr + sizeof(*iref) + namelen > end)) {
1583 			inode_ref_err(leaf, slot,
1584 				"inode ref overflow, ptr %lu end %lu namelen %u",
1585 				ptr, end, namelen);
1586 			return -EUCLEAN;
1587 		}
1588 
1589 		/*
1590 		 * NOTE: In theory we should record all found index numbers
1591 		 * to find any duplicated indexes, but that will be too time
1592 		 * consuming for inodes with too many hard links.
1593 		 */
1594 		ptr += sizeof(*iref) + namelen;
1595 	}
1596 	return 0;
1597 }
1598 
1599 /*
1600  * Common point to switch the item-specific validation.
1601  */
check_leaf_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1602 static int check_leaf_item(struct extent_buffer *leaf,
1603 			   struct btrfs_key *key, int slot,
1604 			   struct btrfs_key *prev_key)
1605 {
1606 	int ret = 0;
1607 	struct btrfs_chunk *chunk;
1608 
1609 	switch (key->type) {
1610 	case BTRFS_EXTENT_DATA_KEY:
1611 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1612 		break;
1613 	case BTRFS_EXTENT_CSUM_KEY:
1614 		ret = check_csum_item(leaf, key, slot, prev_key);
1615 		break;
1616 	case BTRFS_DIR_ITEM_KEY:
1617 	case BTRFS_DIR_INDEX_KEY:
1618 	case BTRFS_XATTR_ITEM_KEY:
1619 		ret = check_dir_item(leaf, key, prev_key, slot);
1620 		break;
1621 	case BTRFS_INODE_REF_KEY:
1622 		ret = check_inode_ref(leaf, key, prev_key, slot);
1623 		break;
1624 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1625 		ret = check_block_group_item(leaf, key, slot);
1626 		break;
1627 	case BTRFS_CHUNK_ITEM_KEY:
1628 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1629 		ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1630 		break;
1631 	case BTRFS_DEV_ITEM_KEY:
1632 		ret = check_dev_item(leaf, key, slot);
1633 		break;
1634 	case BTRFS_INODE_ITEM_KEY:
1635 		ret = check_inode_item(leaf, key, slot);
1636 		break;
1637 	case BTRFS_ROOT_ITEM_KEY:
1638 		ret = check_root_item(leaf, key, slot);
1639 		break;
1640 	case BTRFS_EXTENT_ITEM_KEY:
1641 	case BTRFS_METADATA_ITEM_KEY:
1642 		ret = check_extent_item(leaf, key, slot, prev_key);
1643 		break;
1644 	case BTRFS_TREE_BLOCK_REF_KEY:
1645 	case BTRFS_SHARED_DATA_REF_KEY:
1646 	case BTRFS_SHARED_BLOCK_REF_KEY:
1647 		ret = check_simple_keyed_refs(leaf, key, slot);
1648 		break;
1649 	case BTRFS_EXTENT_DATA_REF_KEY:
1650 		ret = check_extent_data_ref(leaf, key, slot);
1651 		break;
1652 	}
1653 	return ret;
1654 }
1655 
check_leaf(struct extent_buffer * leaf,bool check_item_data)1656 static int check_leaf(struct extent_buffer *leaf, bool check_item_data)
1657 {
1658 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1659 	/* No valid key type is 0, so all key should be larger than this key */
1660 	struct btrfs_key prev_key = {0, 0, 0};
1661 	struct btrfs_key key;
1662 	u32 nritems = btrfs_header_nritems(leaf);
1663 	int slot;
1664 
1665 	if (unlikely(btrfs_header_level(leaf) != 0)) {
1666 		generic_err(leaf, 0,
1667 			"invalid level for leaf, have %d expect 0",
1668 			btrfs_header_level(leaf));
1669 		return -EUCLEAN;
1670 	}
1671 
1672 	/*
1673 	 * Extent buffers from a relocation tree have a owner field that
1674 	 * corresponds to the subvolume tree they are based on. So just from an
1675 	 * extent buffer alone we can not find out what is the id of the
1676 	 * corresponding subvolume tree, so we can not figure out if the extent
1677 	 * buffer corresponds to the root of the relocation tree or not. So
1678 	 * skip this check for relocation trees.
1679 	 */
1680 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1681 		u64 owner = btrfs_header_owner(leaf);
1682 
1683 		/* These trees must never be empty */
1684 		if (unlikely(owner == BTRFS_ROOT_TREE_OBJECTID ||
1685 			     owner == BTRFS_CHUNK_TREE_OBJECTID ||
1686 			     owner == BTRFS_EXTENT_TREE_OBJECTID ||
1687 			     owner == BTRFS_DEV_TREE_OBJECTID ||
1688 			     owner == BTRFS_FS_TREE_OBJECTID ||
1689 			     owner == BTRFS_DATA_RELOC_TREE_OBJECTID)) {
1690 			generic_err(leaf, 0,
1691 			"invalid root, root %llu must never be empty",
1692 				    owner);
1693 			return -EUCLEAN;
1694 		}
1695 		/* Unknown tree */
1696 		if (unlikely(owner == 0)) {
1697 			generic_err(leaf, 0,
1698 				"invalid owner, root 0 is not defined");
1699 			return -EUCLEAN;
1700 		}
1701 		return 0;
1702 	}
1703 
1704 	if (unlikely(nritems == 0))
1705 		return 0;
1706 
1707 	/*
1708 	 * Check the following things to make sure this is a good leaf, and
1709 	 * leaf users won't need to bother with similar sanity checks:
1710 	 *
1711 	 * 1) key ordering
1712 	 * 2) item offset and size
1713 	 *    No overlap, no hole, all inside the leaf.
1714 	 * 3) item content
1715 	 *    If possible, do comprehensive sanity check.
1716 	 *    NOTE: All checks must only rely on the item data itself.
1717 	 */
1718 	for (slot = 0; slot < nritems; slot++) {
1719 		u32 item_end_expected;
1720 		int ret;
1721 
1722 		btrfs_item_key_to_cpu(leaf, &key, slot);
1723 
1724 		/* Make sure the keys are in the right order */
1725 		if (unlikely(btrfs_comp_cpu_keys(&prev_key, &key) >= 0)) {
1726 			generic_err(leaf, slot,
1727 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1728 				prev_key.objectid, prev_key.type,
1729 				prev_key.offset, key.objectid, key.type,
1730 				key.offset);
1731 			return -EUCLEAN;
1732 		}
1733 
1734 		/*
1735 		 * Make sure the offset and ends are right, remember that the
1736 		 * item data starts at the end of the leaf and grows towards the
1737 		 * front.
1738 		 */
1739 		if (slot == 0)
1740 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1741 		else
1742 			item_end_expected = btrfs_item_offset_nr(leaf,
1743 								 slot - 1);
1744 		if (unlikely(btrfs_item_end_nr(leaf, slot) != item_end_expected)) {
1745 			generic_err(leaf, slot,
1746 				"unexpected item end, have %u expect %u",
1747 				btrfs_item_end_nr(leaf, slot),
1748 				item_end_expected);
1749 			return -EUCLEAN;
1750 		}
1751 
1752 		/*
1753 		 * Check to make sure that we don't point outside of the leaf,
1754 		 * just in case all the items are consistent to each other, but
1755 		 * all point outside of the leaf.
1756 		 */
1757 		if (unlikely(btrfs_item_end_nr(leaf, slot) >
1758 			     BTRFS_LEAF_DATA_SIZE(fs_info))) {
1759 			generic_err(leaf, slot,
1760 			"slot end outside of leaf, have %u expect range [0, %u]",
1761 				btrfs_item_end_nr(leaf, slot),
1762 				BTRFS_LEAF_DATA_SIZE(fs_info));
1763 			return -EUCLEAN;
1764 		}
1765 
1766 		/* Also check if the item pointer overlaps with btrfs item. */
1767 		if (unlikely(btrfs_item_ptr_offset(leaf, slot) <
1768 			     btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item))) {
1769 			generic_err(leaf, slot,
1770 		"slot overlaps with its data, item end %lu data start %lu",
1771 				btrfs_item_nr_offset(slot) +
1772 				sizeof(struct btrfs_item),
1773 				btrfs_item_ptr_offset(leaf, slot));
1774 			return -EUCLEAN;
1775 		}
1776 
1777 		if (check_item_data) {
1778 			/*
1779 			 * Check if the item size and content meet other
1780 			 * criteria
1781 			 */
1782 			ret = check_leaf_item(leaf, &key, slot, &prev_key);
1783 			if (unlikely(ret < 0))
1784 				return ret;
1785 		}
1786 
1787 		prev_key.objectid = key.objectid;
1788 		prev_key.type = key.type;
1789 		prev_key.offset = key.offset;
1790 	}
1791 
1792 	return 0;
1793 }
1794 
btrfs_check_leaf_full(struct extent_buffer * leaf)1795 int btrfs_check_leaf_full(struct extent_buffer *leaf)
1796 {
1797 	return check_leaf(leaf, true);
1798 }
1799 ALLOW_ERROR_INJECTION(btrfs_check_leaf_full, ERRNO);
1800 
btrfs_check_leaf_relaxed(struct extent_buffer * leaf)1801 int btrfs_check_leaf_relaxed(struct extent_buffer *leaf)
1802 {
1803 	return check_leaf(leaf, false);
1804 }
1805 
btrfs_check_node(struct extent_buffer * node)1806 int btrfs_check_node(struct extent_buffer *node)
1807 {
1808 	struct btrfs_fs_info *fs_info = node->fs_info;
1809 	unsigned long nr = btrfs_header_nritems(node);
1810 	struct btrfs_key key, next_key;
1811 	int slot;
1812 	int level = btrfs_header_level(node);
1813 	u64 bytenr;
1814 	int ret = 0;
1815 
1816 	if (unlikely(level <= 0 || level >= BTRFS_MAX_LEVEL)) {
1817 		generic_err(node, 0,
1818 			"invalid level for node, have %d expect [1, %d]",
1819 			level, BTRFS_MAX_LEVEL - 1);
1820 		return -EUCLEAN;
1821 	}
1822 	if (unlikely(nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info))) {
1823 		btrfs_crit(fs_info,
1824 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1825 			   btrfs_header_owner(node), node->start,
1826 			   nr == 0 ? "small" : "large", nr,
1827 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1828 		return -EUCLEAN;
1829 	}
1830 
1831 	for (slot = 0; slot < nr - 1; slot++) {
1832 		bytenr = btrfs_node_blockptr(node, slot);
1833 		btrfs_node_key_to_cpu(node, &key, slot);
1834 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1835 
1836 		if (unlikely(!bytenr)) {
1837 			generic_err(node, slot,
1838 				"invalid NULL node pointer");
1839 			ret = -EUCLEAN;
1840 			goto out;
1841 		}
1842 		if (unlikely(!IS_ALIGNED(bytenr, fs_info->sectorsize))) {
1843 			generic_err(node, slot,
1844 			"unaligned pointer, have %llu should be aligned to %u",
1845 				bytenr, fs_info->sectorsize);
1846 			ret = -EUCLEAN;
1847 			goto out;
1848 		}
1849 
1850 		if (unlikely(btrfs_comp_cpu_keys(&key, &next_key) >= 0)) {
1851 			generic_err(node, slot,
1852 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1853 				key.objectid, key.type, key.offset,
1854 				next_key.objectid, next_key.type,
1855 				next_key.offset);
1856 			ret = -EUCLEAN;
1857 			goto out;
1858 		}
1859 	}
1860 out:
1861 	return ret;
1862 }
1863 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
1864