• 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 
27 /*
28  * Error message should follow the following format:
29  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
30  *
31  * @type:	leaf or node
32  * @identifier:	the necessary info to locate the leaf/node.
33  * 		It's recommended to decode key.objecitd/offset if it's
34  * 		meaningful.
35  * @reason:	describe the error
36  * @bad_value:	optional, it's recommended to output bad value and its
37  *		expected value (range).
38  *
39  * Since comma is used to separate the components, only space is allowed
40  * inside each component.
41  */
42 
43 /*
44  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
45  * Allows callers to customize the output.
46  */
47 __printf(3, 4)
48 __cold
generic_err(const struct extent_buffer * eb,int slot,const char * fmt,...)49 static void generic_err(const struct extent_buffer *eb, int slot,
50 			const char *fmt, ...)
51 {
52 	const struct btrfs_fs_info *fs_info = eb->fs_info;
53 	struct va_format vaf;
54 	va_list args;
55 
56 	va_start(args, fmt);
57 
58 	vaf.fmt = fmt;
59 	vaf.va = &args;
60 
61 	btrfs_crit(fs_info,
62 		"corrupt %s: root=%llu block=%llu slot=%d, %pV",
63 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
64 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
65 	va_end(args);
66 }
67 
68 /*
69  * Customized reporter for extent data item, since its key objectid and
70  * offset has its own meaning.
71  */
72 __printf(3, 4)
73 __cold
file_extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)74 static void file_extent_err(const struct extent_buffer *eb, int slot,
75 			    const char *fmt, ...)
76 {
77 	const struct btrfs_fs_info *fs_info = eb->fs_info;
78 	struct btrfs_key key;
79 	struct va_format vaf;
80 	va_list args;
81 
82 	btrfs_item_key_to_cpu(eb, &key, slot);
83 	va_start(args, fmt);
84 
85 	vaf.fmt = fmt;
86 	vaf.va = &args;
87 
88 	btrfs_crit(fs_info,
89 	"corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
90 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
91 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
92 		key.objectid, key.offset, &vaf);
93 	va_end(args);
94 }
95 
96 /*
97  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
98  * Else return 1
99  */
100 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)		      \
101 ({									      \
102 	if (!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment))) \
103 		file_extent_err((leaf), (slot),				      \
104 	"invalid %s for file extent, have %llu, should be aligned to %u",     \
105 			(#name), btrfs_file_extent_##name((leaf), (fi)),      \
106 			(alignment));					      \
107 	(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
108 })
109 
file_extent_end(struct extent_buffer * leaf,struct btrfs_key * key,struct btrfs_file_extent_item * extent)110 static u64 file_extent_end(struct extent_buffer *leaf,
111 			   struct btrfs_key *key,
112 			   struct btrfs_file_extent_item *extent)
113 {
114 	u64 end;
115 	u64 len;
116 
117 	if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
118 		len = btrfs_file_extent_ram_bytes(leaf, extent);
119 		end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
120 	} else {
121 		len = btrfs_file_extent_num_bytes(leaf, extent);
122 		end = key->offset + len;
123 	}
124 	return end;
125 }
126 
check_extent_data_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)127 static int check_extent_data_item(struct extent_buffer *leaf,
128 				  struct btrfs_key *key, int slot,
129 				  struct btrfs_key *prev_key)
130 {
131 	struct btrfs_fs_info *fs_info = leaf->fs_info;
132 	struct btrfs_file_extent_item *fi;
133 	u32 sectorsize = fs_info->sectorsize;
134 	u32 item_size = btrfs_item_size_nr(leaf, slot);
135 	u64 extent_end;
136 
137 	if (!IS_ALIGNED(key->offset, sectorsize)) {
138 		file_extent_err(leaf, slot,
139 "unaligned file_offset for file extent, have %llu should be aligned to %u",
140 			key->offset, sectorsize);
141 		return -EUCLEAN;
142 	}
143 
144 	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
145 
146 	if (btrfs_file_extent_type(leaf, fi) > BTRFS_FILE_EXTENT_TYPES) {
147 		file_extent_err(leaf, slot,
148 		"invalid type for file extent, have %u expect range [0, %u]",
149 			btrfs_file_extent_type(leaf, fi),
150 			BTRFS_FILE_EXTENT_TYPES);
151 		return -EUCLEAN;
152 	}
153 
154 	/*
155 	 * Support for new compression/encryption must introduce incompat flag,
156 	 * and must be caught in open_ctree().
157 	 */
158 	if (btrfs_file_extent_compression(leaf, fi) > BTRFS_COMPRESS_TYPES) {
159 		file_extent_err(leaf, slot,
160 	"invalid compression for file extent, have %u expect range [0, %u]",
161 			btrfs_file_extent_compression(leaf, fi),
162 			BTRFS_COMPRESS_TYPES);
163 		return -EUCLEAN;
164 	}
165 	if (btrfs_file_extent_encryption(leaf, fi)) {
166 		file_extent_err(leaf, slot,
167 			"invalid encryption for file extent, have %u expect 0",
168 			btrfs_file_extent_encryption(leaf, fi));
169 		return -EUCLEAN;
170 	}
171 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
172 		/* Inline extent must have 0 as key offset */
173 		if (key->offset) {
174 			file_extent_err(leaf, slot,
175 		"invalid file_offset for inline file extent, have %llu expect 0",
176 				key->offset);
177 			return -EUCLEAN;
178 		}
179 
180 		/* Compressed inline extent has no on-disk size, skip it */
181 		if (btrfs_file_extent_compression(leaf, fi) !=
182 		    BTRFS_COMPRESS_NONE)
183 			return 0;
184 
185 		/* Uncompressed inline extent size must match item size */
186 		if (item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
187 		    btrfs_file_extent_ram_bytes(leaf, fi)) {
188 			file_extent_err(leaf, slot,
189 	"invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
190 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
191 				btrfs_file_extent_ram_bytes(leaf, fi));
192 			return -EUCLEAN;
193 		}
194 		return 0;
195 	}
196 
197 	/* Regular or preallocated extent has fixed item size */
198 	if (item_size != sizeof(*fi)) {
199 		file_extent_err(leaf, slot,
200 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
201 			item_size, sizeof(*fi));
202 		return -EUCLEAN;
203 	}
204 	if (CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
205 	    CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
206 	    CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
207 	    CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
208 	    CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize))
209 		return -EUCLEAN;
210 
211 	/* Catch extent end overflow */
212 	if (check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
213 			       key->offset, &extent_end)) {
214 		file_extent_err(leaf, slot,
215 	"extent end overflow, have file offset %llu extent num bytes %llu",
216 				key->offset,
217 				btrfs_file_extent_num_bytes(leaf, fi));
218 		return -EUCLEAN;
219 	}
220 
221 	/*
222 	 * Check that no two consecutive file extent items, in the same leaf,
223 	 * present ranges that overlap each other.
224 	 */
225 	if (slot > 0 &&
226 	    prev_key->objectid == key->objectid &&
227 	    prev_key->type == BTRFS_EXTENT_DATA_KEY) {
228 		struct btrfs_file_extent_item *prev_fi;
229 		u64 prev_end;
230 
231 		prev_fi = btrfs_item_ptr(leaf, slot - 1,
232 					 struct btrfs_file_extent_item);
233 		prev_end = file_extent_end(leaf, prev_key, prev_fi);
234 		if (prev_end > key->offset) {
235 			file_extent_err(leaf, slot - 1,
236 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
237 					prev_end, key->offset);
238 			return -EUCLEAN;
239 		}
240 	}
241 
242 	return 0;
243 }
244 
check_csum_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)245 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
246 			   int slot, struct btrfs_key *prev_key)
247 {
248 	struct btrfs_fs_info *fs_info = leaf->fs_info;
249 	u32 sectorsize = fs_info->sectorsize;
250 	u32 csumsize = btrfs_super_csum_size(fs_info->super_copy);
251 
252 	if (key->objectid != BTRFS_EXTENT_CSUM_OBJECTID) {
253 		generic_err(leaf, slot,
254 		"invalid key objectid for csum item, have %llu expect %llu",
255 			key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
256 		return -EUCLEAN;
257 	}
258 	if (!IS_ALIGNED(key->offset, sectorsize)) {
259 		generic_err(leaf, slot,
260 	"unaligned key offset for csum item, have %llu should be aligned to %u",
261 			key->offset, sectorsize);
262 		return -EUCLEAN;
263 	}
264 	if (!IS_ALIGNED(btrfs_item_size_nr(leaf, slot), csumsize)) {
265 		generic_err(leaf, slot,
266 	"unaligned item size for csum item, have %u should be aligned to %u",
267 			btrfs_item_size_nr(leaf, slot), csumsize);
268 		return -EUCLEAN;
269 	}
270 	if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
271 		u64 prev_csum_end;
272 		u32 prev_item_size;
273 
274 		prev_item_size = btrfs_item_size_nr(leaf, slot - 1);
275 		prev_csum_end = (prev_item_size / csumsize) * sectorsize;
276 		prev_csum_end += prev_key->offset;
277 		if (prev_csum_end > key->offset) {
278 			generic_err(leaf, slot - 1,
279 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
280 				    prev_csum_end, key->offset);
281 			return -EUCLEAN;
282 		}
283 	}
284 	return 0;
285 }
286 
287 /*
288  * Customized reported for dir_item, only important new info is key->objectid,
289  * which represents inode number
290  */
291 __printf(3, 4)
292 __cold
dir_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)293 static void dir_item_err(const struct extent_buffer *eb, int slot,
294 			 const char *fmt, ...)
295 {
296 	const struct btrfs_fs_info *fs_info = eb->fs_info;
297 	struct btrfs_key key;
298 	struct va_format vaf;
299 	va_list args;
300 
301 	btrfs_item_key_to_cpu(eb, &key, slot);
302 	va_start(args, fmt);
303 
304 	vaf.fmt = fmt;
305 	vaf.va = &args;
306 
307 	btrfs_crit(fs_info,
308 	"corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
309 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
310 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
311 		key.objectid, &vaf);
312 	va_end(args);
313 }
314 
check_dir_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)315 static int check_dir_item(struct extent_buffer *leaf,
316 			  struct btrfs_key *key, int slot)
317 {
318 	struct btrfs_fs_info *fs_info = leaf->fs_info;
319 	struct btrfs_dir_item *di;
320 	u32 item_size = btrfs_item_size_nr(leaf, slot);
321 	u32 cur = 0;
322 
323 	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
324 	while (cur < item_size) {
325 		u32 name_len;
326 		u32 data_len;
327 		u32 max_name_len;
328 		u32 total_size;
329 		u32 name_hash;
330 		u8 dir_type;
331 
332 		/* header itself should not cross item boundary */
333 		if (cur + sizeof(*di) > item_size) {
334 			dir_item_err(leaf, slot,
335 		"dir item header crosses item boundary, have %zu boundary %u",
336 				cur + sizeof(*di), item_size);
337 			return -EUCLEAN;
338 		}
339 
340 		/* dir type check */
341 		dir_type = btrfs_dir_type(leaf, di);
342 		if (dir_type >= BTRFS_FT_MAX) {
343 			dir_item_err(leaf, slot,
344 			"invalid dir item type, have %u expect [0, %u)",
345 				dir_type, BTRFS_FT_MAX);
346 			return -EUCLEAN;
347 		}
348 
349 		if (key->type == BTRFS_XATTR_ITEM_KEY &&
350 		    dir_type != BTRFS_FT_XATTR) {
351 			dir_item_err(leaf, slot,
352 		"invalid dir item type for XATTR key, have %u expect %u",
353 				dir_type, BTRFS_FT_XATTR);
354 			return -EUCLEAN;
355 		}
356 		if (dir_type == BTRFS_FT_XATTR &&
357 		    key->type != BTRFS_XATTR_ITEM_KEY) {
358 			dir_item_err(leaf, slot,
359 			"xattr dir type found for non-XATTR key");
360 			return -EUCLEAN;
361 		}
362 		if (dir_type == BTRFS_FT_XATTR)
363 			max_name_len = XATTR_NAME_MAX;
364 		else
365 			max_name_len = BTRFS_NAME_LEN;
366 
367 		/* Name/data length check */
368 		name_len = btrfs_dir_name_len(leaf, di);
369 		data_len = btrfs_dir_data_len(leaf, di);
370 		if (name_len > max_name_len) {
371 			dir_item_err(leaf, slot,
372 			"dir item name len too long, have %u max %u",
373 				name_len, max_name_len);
374 			return -EUCLEAN;
375 		}
376 		if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info)) {
377 			dir_item_err(leaf, slot,
378 			"dir item name and data len too long, have %u max %u",
379 				name_len + data_len,
380 				BTRFS_MAX_XATTR_SIZE(fs_info));
381 			return -EUCLEAN;
382 		}
383 
384 		if (data_len && dir_type != BTRFS_FT_XATTR) {
385 			dir_item_err(leaf, slot,
386 			"dir item with invalid data len, have %u expect 0",
387 				data_len);
388 			return -EUCLEAN;
389 		}
390 
391 		total_size = sizeof(*di) + name_len + data_len;
392 
393 		/* header and name/data should not cross item boundary */
394 		if (cur + total_size > item_size) {
395 			dir_item_err(leaf, slot,
396 		"dir item data crosses item boundary, have %u boundary %u",
397 				cur + total_size, item_size);
398 			return -EUCLEAN;
399 		}
400 
401 		/*
402 		 * Special check for XATTR/DIR_ITEM, as key->offset is name
403 		 * hash, should match its name
404 		 */
405 		if (key->type == BTRFS_DIR_ITEM_KEY ||
406 		    key->type == BTRFS_XATTR_ITEM_KEY) {
407 			char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
408 
409 			read_extent_buffer(leaf, namebuf,
410 					(unsigned long)(di + 1), name_len);
411 			name_hash = btrfs_name_hash(namebuf, name_len);
412 			if (key->offset != name_hash) {
413 				dir_item_err(leaf, slot,
414 		"name hash mismatch with key, have 0x%016x expect 0x%016llx",
415 					name_hash, key->offset);
416 				return -EUCLEAN;
417 			}
418 		}
419 		cur += total_size;
420 		di = (struct btrfs_dir_item *)((void *)di + total_size);
421 	}
422 	return 0;
423 }
424 
425 __printf(3, 4)
426 __cold
block_group_err(const struct extent_buffer * eb,int slot,const char * fmt,...)427 static void block_group_err(const struct extent_buffer *eb, int slot,
428 			    const char *fmt, ...)
429 {
430 	const struct btrfs_fs_info *fs_info = eb->fs_info;
431 	struct btrfs_key key;
432 	struct va_format vaf;
433 	va_list args;
434 
435 	btrfs_item_key_to_cpu(eb, &key, slot);
436 	va_start(args, fmt);
437 
438 	vaf.fmt = fmt;
439 	vaf.va = &args;
440 
441 	btrfs_crit(fs_info,
442 	"corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
443 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
444 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
445 		key.objectid, key.offset, &vaf);
446 	va_end(args);
447 }
448 
check_block_group_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)449 static int check_block_group_item(struct extent_buffer *leaf,
450 				  struct btrfs_key *key, int slot)
451 {
452 	struct btrfs_block_group_item bgi;
453 	u32 item_size = btrfs_item_size_nr(leaf, slot);
454 	u64 flags;
455 	u64 type;
456 
457 	/*
458 	 * Here we don't really care about alignment since extent allocator can
459 	 * handle it.  We care more about the size.
460 	 */
461 	if (key->offset == 0) {
462 		block_group_err(leaf, slot,
463 				"invalid block group size 0");
464 		return -EUCLEAN;
465 	}
466 
467 	if (item_size != sizeof(bgi)) {
468 		block_group_err(leaf, slot,
469 			"invalid item size, have %u expect %zu",
470 				item_size, sizeof(bgi));
471 		return -EUCLEAN;
472 	}
473 
474 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
475 			   sizeof(bgi));
476 	if (btrfs_block_group_chunk_objectid(&bgi) !=
477 	    BTRFS_FIRST_CHUNK_TREE_OBJECTID) {
478 		block_group_err(leaf, slot,
479 		"invalid block group chunk objectid, have %llu expect %llu",
480 				btrfs_block_group_chunk_objectid(&bgi),
481 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
482 		return -EUCLEAN;
483 	}
484 
485 	if (btrfs_block_group_used(&bgi) > key->offset) {
486 		block_group_err(leaf, slot,
487 			"invalid block group used, have %llu expect [0, %llu)",
488 				btrfs_block_group_used(&bgi), key->offset);
489 		return -EUCLEAN;
490 	}
491 
492 	flags = btrfs_block_group_flags(&bgi);
493 	if (hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1) {
494 		block_group_err(leaf, slot,
495 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
496 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
497 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
498 		return -EUCLEAN;
499 	}
500 
501 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
502 	if (type != BTRFS_BLOCK_GROUP_DATA &&
503 	    type != BTRFS_BLOCK_GROUP_METADATA &&
504 	    type != BTRFS_BLOCK_GROUP_SYSTEM &&
505 	    type != (BTRFS_BLOCK_GROUP_METADATA |
506 			   BTRFS_BLOCK_GROUP_DATA)) {
507 		block_group_err(leaf, slot,
508 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
509 			type, hweight64(type),
510 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
511 			BTRFS_BLOCK_GROUP_SYSTEM,
512 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
513 		return -EUCLEAN;
514 	}
515 	return 0;
516 }
517 
518 __printf(4, 5)
519 __cold
chunk_err(const struct extent_buffer * leaf,const struct btrfs_chunk * chunk,u64 logical,const char * fmt,...)520 static void chunk_err(const struct extent_buffer *leaf,
521 		      const struct btrfs_chunk *chunk, u64 logical,
522 		      const char *fmt, ...)
523 {
524 	const struct btrfs_fs_info *fs_info = leaf->fs_info;
525 	bool is_sb;
526 	struct va_format vaf;
527 	va_list args;
528 	int i;
529 	int slot = -1;
530 
531 	/* Only superblock eb is able to have such small offset */
532 	is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
533 
534 	if (!is_sb) {
535 		/*
536 		 * Get the slot number by iterating through all slots, this
537 		 * would provide better readability.
538 		 */
539 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
540 			if (btrfs_item_ptr_offset(leaf, i) ==
541 					(unsigned long)chunk) {
542 				slot = i;
543 				break;
544 			}
545 		}
546 	}
547 	va_start(args, fmt);
548 	vaf.fmt = fmt;
549 	vaf.va = &args;
550 
551 	if (is_sb)
552 		btrfs_crit(fs_info,
553 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
554 			   logical, &vaf);
555 	else
556 		btrfs_crit(fs_info,
557 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
558 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
559 			   logical, &vaf);
560 	va_end(args);
561 }
562 
563 /*
564  * The common chunk check which could also work on super block sys chunk array.
565  *
566  * Return -EUCLEAN if anything is corrupted.
567  * Return 0 if everything is OK.
568  */
btrfs_check_chunk_valid(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 logical)569 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
570 			    struct btrfs_chunk *chunk, u64 logical)
571 {
572 	struct btrfs_fs_info *fs_info = leaf->fs_info;
573 	u64 length;
574 	u64 chunk_end;
575 	u64 stripe_len;
576 	u16 num_stripes;
577 	u16 sub_stripes;
578 	u64 type;
579 	u64 features;
580 	bool mixed = false;
581 	int raid_index;
582 	int nparity;
583 	int ncopies;
584 
585 	length = btrfs_chunk_length(leaf, chunk);
586 	stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
587 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
588 	sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
589 	type = btrfs_chunk_type(leaf, chunk);
590 	raid_index = btrfs_bg_flags_to_raid_index(type);
591 	ncopies = btrfs_raid_array[raid_index].ncopies;
592 	nparity = btrfs_raid_array[raid_index].nparity;
593 
594 	if (!num_stripes) {
595 		chunk_err(leaf, chunk, logical,
596 			  "invalid chunk num_stripes, have %u", num_stripes);
597 		return -EUCLEAN;
598 	}
599 	if (num_stripes < ncopies) {
600 		chunk_err(leaf, chunk, logical,
601 			  "invalid chunk num_stripes < ncopies, have %u < %d",
602 			  num_stripes, ncopies);
603 		return -EUCLEAN;
604 	}
605 	if (nparity && num_stripes == nparity) {
606 		chunk_err(leaf, chunk, logical,
607 			  "invalid chunk num_stripes == nparity, have %u == %d",
608 			  num_stripes, nparity);
609 		return -EUCLEAN;
610 	}
611 	if (!IS_ALIGNED(logical, fs_info->sectorsize)) {
612 		chunk_err(leaf, chunk, logical,
613 		"invalid chunk logical, have %llu should aligned to %u",
614 			  logical, fs_info->sectorsize);
615 		return -EUCLEAN;
616 	}
617 	if (btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize) {
618 		chunk_err(leaf, chunk, logical,
619 			  "invalid chunk sectorsize, have %u expect %u",
620 			  btrfs_chunk_sector_size(leaf, chunk),
621 			  fs_info->sectorsize);
622 		return -EUCLEAN;
623 	}
624 	if (!length || !IS_ALIGNED(length, fs_info->sectorsize)) {
625 		chunk_err(leaf, chunk, logical,
626 			  "invalid chunk length, have %llu", length);
627 		return -EUCLEAN;
628 	}
629 	if (unlikely(check_add_overflow(logical, length, &chunk_end))) {
630 		chunk_err(leaf, chunk, logical,
631 "invalid chunk logical start and length, have logical start %llu length %llu",
632 			  logical, length);
633 		return -EUCLEAN;
634 	}
635 	if (!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN) {
636 		chunk_err(leaf, chunk, logical,
637 			  "invalid chunk stripe length: %llu",
638 			  stripe_len);
639 		return -EUCLEAN;
640 	}
641 	if (~(BTRFS_BLOCK_GROUP_TYPE_MASK | BTRFS_BLOCK_GROUP_PROFILE_MASK) &
642 	    type) {
643 		chunk_err(leaf, chunk, logical,
644 			  "unrecognized chunk type: 0x%llx",
645 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
646 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) &
647 			  btrfs_chunk_type(leaf, chunk));
648 		return -EUCLEAN;
649 	}
650 
651 	if (!is_power_of_2(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
652 	    (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0) {
653 		chunk_err(leaf, chunk, logical,
654 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
655 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
656 		return -EUCLEAN;
657 	}
658 	if ((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0) {
659 		chunk_err(leaf, chunk, logical,
660 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
661 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
662 		return -EUCLEAN;
663 	}
664 
665 	if ((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
666 	    (type & (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA))) {
667 		chunk_err(leaf, chunk, logical,
668 			  "system chunk with data or metadata type: 0x%llx",
669 			  type);
670 		return -EUCLEAN;
671 	}
672 
673 	features = btrfs_super_incompat_flags(fs_info->super_copy);
674 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
675 		mixed = true;
676 
677 	if (!mixed) {
678 		if ((type & BTRFS_BLOCK_GROUP_METADATA) &&
679 		    (type & BTRFS_BLOCK_GROUP_DATA)) {
680 			chunk_err(leaf, chunk, logical,
681 			"mixed chunk type in non-mixed mode: 0x%llx", type);
682 			return -EUCLEAN;
683 		}
684 	}
685 
686 	if ((type & BTRFS_BLOCK_GROUP_RAID10 && sub_stripes != 2) ||
687 	    (type & BTRFS_BLOCK_GROUP_RAID1 && num_stripes != 2) ||
688 	    (type & BTRFS_BLOCK_GROUP_RAID5 && num_stripes < 2) ||
689 	    (type & BTRFS_BLOCK_GROUP_RAID6 && num_stripes < 3) ||
690 	    (type & BTRFS_BLOCK_GROUP_DUP && num_stripes != 2) ||
691 	    ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 && num_stripes != 1)) {
692 		chunk_err(leaf, chunk, logical,
693 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
694 			num_stripes, sub_stripes,
695 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
696 		return -EUCLEAN;
697 	}
698 
699 	return 0;
700 }
701 
702 /*
703  * Enhanced version of chunk item checker.
704  *
705  * The common btrfs_check_chunk_valid() doesn't check item size since it needs
706  * to work on super block sys_chunk_array which doesn't have full item ptr.
707  */
check_leaf_chunk_item(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_key * key,int slot)708 static int check_leaf_chunk_item(struct extent_buffer *leaf,
709 				 struct btrfs_chunk *chunk,
710 				 struct btrfs_key *key, int slot)
711 {
712 	int num_stripes;
713 
714 	if (btrfs_item_size_nr(leaf, slot) < sizeof(struct btrfs_chunk)) {
715 		chunk_err(leaf, chunk, key->offset,
716 			"invalid chunk item size: have %u expect [%zu, %u)",
717 			btrfs_item_size_nr(leaf, slot),
718 			sizeof(struct btrfs_chunk),
719 			BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
720 		return -EUCLEAN;
721 	}
722 
723 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
724 	/* Let btrfs_check_chunk_valid() handle this error type */
725 	if (num_stripes == 0)
726 		goto out;
727 
728 	if (btrfs_chunk_item_size(num_stripes) !=
729 	    btrfs_item_size_nr(leaf, slot)) {
730 		chunk_err(leaf, chunk, key->offset,
731 			"invalid chunk item size: have %u expect %lu",
732 			btrfs_item_size_nr(leaf, slot),
733 			btrfs_chunk_item_size(num_stripes));
734 		return -EUCLEAN;
735 	}
736 out:
737 	return btrfs_check_chunk_valid(leaf, chunk, key->offset);
738 }
739 
740 __printf(3, 4)
741 __cold
dev_item_err(const struct extent_buffer * eb,int slot,const char * fmt,...)742 static void dev_item_err(const struct extent_buffer *eb, int slot,
743 			 const char *fmt, ...)
744 {
745 	struct btrfs_key key;
746 	struct va_format vaf;
747 	va_list args;
748 
749 	btrfs_item_key_to_cpu(eb, &key, slot);
750 	va_start(args, fmt);
751 
752 	vaf.fmt = fmt;
753 	vaf.va = &args;
754 
755 	btrfs_crit(eb->fs_info,
756 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
757 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
758 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
759 		key.objectid, &vaf);
760 	va_end(args);
761 }
762 
check_dev_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)763 static int check_dev_item(struct extent_buffer *leaf,
764 			  struct btrfs_key *key, int slot)
765 {
766 	struct btrfs_dev_item *ditem;
767 
768 	if (key->objectid != BTRFS_DEV_ITEMS_OBJECTID) {
769 		dev_item_err(leaf, slot,
770 			     "invalid objectid: has=%llu expect=%llu",
771 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
772 		return -EUCLEAN;
773 	}
774 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
775 	if (btrfs_device_id(leaf, ditem) != key->offset) {
776 		dev_item_err(leaf, slot,
777 			     "devid mismatch: key has=%llu item has=%llu",
778 			     key->offset, btrfs_device_id(leaf, ditem));
779 		return -EUCLEAN;
780 	}
781 
782 	/*
783 	 * For device total_bytes, we don't have reliable way to check it, as
784 	 * it can be 0 for device removal. Device size check can only be done
785 	 * by dev extents check.
786 	 */
787 	if (btrfs_device_bytes_used(leaf, ditem) >
788 	    btrfs_device_total_bytes(leaf, ditem)) {
789 		dev_item_err(leaf, slot,
790 			     "invalid bytes used: have %llu expect [0, %llu]",
791 			     btrfs_device_bytes_used(leaf, ditem),
792 			     btrfs_device_total_bytes(leaf, ditem));
793 		return -EUCLEAN;
794 	}
795 	/*
796 	 * Remaining members like io_align/type/gen/dev_group aren't really
797 	 * utilized.  Skip them to make later usage of them easier.
798 	 */
799 	return 0;
800 }
801 
802 /* Inode item error output has the same format as dir_item_err() */
803 #define inode_item_err(fs_info, eb, slot, fmt, ...)			\
804 	dir_item_err(eb, slot, fmt, __VA_ARGS__)
805 
check_inode_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)806 static int check_inode_item(struct extent_buffer *leaf,
807 			    struct btrfs_key *key, int slot)
808 {
809 	struct btrfs_fs_info *fs_info = leaf->fs_info;
810 	struct btrfs_inode_item *iitem;
811 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
812 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
813 	u32 mode;
814 
815 	if ((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
816 	     key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
817 	    key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
818 	    key->objectid != BTRFS_FREE_INO_OBJECTID) {
819 		generic_err(leaf, slot,
820 	"invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
821 			    key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
822 			    BTRFS_FIRST_FREE_OBJECTID,
823 			    BTRFS_LAST_FREE_OBJECTID,
824 			    BTRFS_FREE_INO_OBJECTID);
825 		return -EUCLEAN;
826 	}
827 	if (key->offset != 0) {
828 		inode_item_err(fs_info, leaf, slot,
829 			"invalid key offset: has %llu expect 0",
830 			key->offset);
831 		return -EUCLEAN;
832 	}
833 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
834 
835 	/* Here we use super block generation + 1 to handle log tree */
836 	if (btrfs_inode_generation(leaf, iitem) > super_gen + 1) {
837 		inode_item_err(fs_info, leaf, slot,
838 			"invalid inode transid: has %llu expect [0, %llu]",
839 			       btrfs_inode_generation(leaf, iitem),
840 			       super_gen + 1);
841 		return -EUCLEAN;
842 	}
843 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
844 	if (btrfs_inode_transid(leaf, iitem) > super_gen + 1) {
845 		inode_item_err(fs_info, leaf, slot,
846 			"invalid inode generation: has %llu expect [0, %llu]",
847 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
848 		return -EUCLEAN;
849 	}
850 
851 	/*
852 	 * For size and nbytes it's better not to be too strict, as for dir
853 	 * item its size/nbytes can easily get wrong, but doesn't affect
854 	 * anything in the fs. So here we skip the check.
855 	 */
856 	mode = btrfs_inode_mode(leaf, iitem);
857 	if (mode & ~valid_mask) {
858 		inode_item_err(fs_info, leaf, slot,
859 			       "unknown mode bit detected: 0x%x",
860 			       mode & ~valid_mask);
861 		return -EUCLEAN;
862 	}
863 
864 	/*
865 	 * S_IFMT is not bit mapped so we can't completely rely on is_power_of_2,
866 	 * but is_power_of_2() can save us from checking FIFO/CHR/DIR/REG.
867 	 * Only needs to check BLK, LNK and SOCKS
868 	 */
869 	if (!is_power_of_2(mode & S_IFMT)) {
870 		if (!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode)) {
871 			inode_item_err(fs_info, leaf, slot,
872 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
873 				       mode & S_IFMT);
874 			return -EUCLEAN;
875 		}
876 	}
877 	if (S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1) {
878 		inode_item_err(fs_info, leaf, slot,
879 		       "invalid nlink: has %u expect no more than 1 for dir",
880 			btrfs_inode_nlink(leaf, iitem));
881 		return -EUCLEAN;
882 	}
883 	if (btrfs_inode_flags(leaf, iitem) & ~BTRFS_INODE_FLAG_MASK) {
884 		inode_item_err(fs_info, leaf, slot,
885 			       "unknown flags detected: 0x%llx",
886 			       btrfs_inode_flags(leaf, iitem) &
887 			       ~BTRFS_INODE_FLAG_MASK);
888 		return -EUCLEAN;
889 	}
890 	return 0;
891 }
892 
check_root_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot)893 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
894 			   int slot)
895 {
896 	struct btrfs_fs_info *fs_info = leaf->fs_info;
897 	struct btrfs_root_item ri = { 0 };
898 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
899 				     BTRFS_ROOT_SUBVOL_DEAD;
900 
901 	/* No such tree id */
902 	if (key->objectid == 0) {
903 		generic_err(leaf, slot, "invalid root id 0");
904 		return -EUCLEAN;
905 	}
906 
907 	/*
908 	 * Some older kernel may create ROOT_ITEM with non-zero offset, so here
909 	 * we only check offset for reloc tree whose key->offset must be a
910 	 * valid tree.
911 	 */
912 	if (key->objectid == BTRFS_TREE_RELOC_OBJECTID && key->offset == 0) {
913 		generic_err(leaf, slot, "invalid root id 0 for reloc tree");
914 		return -EUCLEAN;
915 	}
916 
917 	if (btrfs_item_size_nr(leaf, slot) != sizeof(ri) &&
918 	    btrfs_item_size_nr(leaf, slot) != btrfs_legacy_root_item_size()) {
919 		generic_err(leaf, slot,
920 			    "invalid root item size, have %u expect %zu or %u",
921 			    btrfs_item_size_nr(leaf, slot), sizeof(ri),
922 			    btrfs_legacy_root_item_size());
923 		return -EUCLEAN;
924 	}
925 
926 	/*
927 	 * For legacy root item, the members starting at generation_v2 will be
928 	 * all filled with 0.
929 	 * And since we allow geneartion_v2 as 0, it will still pass the check.
930 	 */
931 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
932 			   btrfs_item_size_nr(leaf, slot));
933 
934 	/* Generation related */
935 	if (btrfs_root_generation(&ri) >
936 	    btrfs_super_generation(fs_info->super_copy) + 1) {
937 		generic_err(leaf, slot,
938 			"invalid root generation, have %llu expect (0, %llu]",
939 			    btrfs_root_generation(&ri),
940 			    btrfs_super_generation(fs_info->super_copy) + 1);
941 		return -EUCLEAN;
942 	}
943 	if (btrfs_root_generation_v2(&ri) >
944 	    btrfs_super_generation(fs_info->super_copy) + 1) {
945 		generic_err(leaf, slot,
946 		"invalid root v2 generation, have %llu expect (0, %llu]",
947 			    btrfs_root_generation_v2(&ri),
948 			    btrfs_super_generation(fs_info->super_copy) + 1);
949 		return -EUCLEAN;
950 	}
951 	if (btrfs_root_last_snapshot(&ri) >
952 	    btrfs_super_generation(fs_info->super_copy) + 1) {
953 		generic_err(leaf, slot,
954 		"invalid root last_snapshot, have %llu expect (0, %llu]",
955 			    btrfs_root_last_snapshot(&ri),
956 			    btrfs_super_generation(fs_info->super_copy) + 1);
957 		return -EUCLEAN;
958 	}
959 
960 	/* Alignment and level check */
961 	if (!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize)) {
962 		generic_err(leaf, slot,
963 		"invalid root bytenr, have %llu expect to be aligned to %u",
964 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
965 		return -EUCLEAN;
966 	}
967 	if (btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL) {
968 		generic_err(leaf, slot,
969 			    "invalid root level, have %u expect [0, %u]",
970 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
971 		return -EUCLEAN;
972 	}
973 	if (ri.drop_level >= BTRFS_MAX_LEVEL) {
974 		generic_err(leaf, slot,
975 			    "invalid root level, have %u expect [0, %u]",
976 			    ri.drop_level, BTRFS_MAX_LEVEL - 1);
977 		return -EUCLEAN;
978 	}
979 
980 	/* Flags check */
981 	if (btrfs_root_flags(&ri) & ~valid_root_flags) {
982 		generic_err(leaf, slot,
983 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
984 			    btrfs_root_flags(&ri), valid_root_flags);
985 		return -EUCLEAN;
986 	}
987 	return 0;
988 }
989 
990 __printf(3,4)
991 __cold
extent_err(const struct extent_buffer * eb,int slot,const char * fmt,...)992 static void extent_err(const struct extent_buffer *eb, int slot,
993 		       const char *fmt, ...)
994 {
995 	struct btrfs_key key;
996 	struct va_format vaf;
997 	va_list args;
998 	u64 bytenr;
999 	u64 len;
1000 
1001 	btrfs_item_key_to_cpu(eb, &key, slot);
1002 	bytenr = key.objectid;
1003 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
1004 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
1005 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
1006 		len = eb->fs_info->nodesize;
1007 	else
1008 		len = key.offset;
1009 	va_start(args, fmt);
1010 
1011 	vaf.fmt = fmt;
1012 	vaf.va = &args;
1013 
1014 	btrfs_crit(eb->fs_info,
1015 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1016 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1017 		eb->start, slot, bytenr, len, &vaf);
1018 	va_end(args);
1019 }
1020 
check_extent_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1021 static int check_extent_item(struct extent_buffer *leaf,
1022 			     struct btrfs_key *key, int slot,
1023 			     struct btrfs_key *prev_key)
1024 {
1025 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1026 	struct btrfs_extent_item *ei;
1027 	bool is_tree_block = false;
1028 	unsigned long ptr;	/* Current pointer inside inline refs */
1029 	unsigned long end;	/* Extent item end */
1030 	const u32 item_size = btrfs_item_size_nr(leaf, slot);
1031 	u64 flags;
1032 	u64 generation;
1033 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1034 	u64 inline_refs = 0;	/* found total inline refs */
1035 
1036 	if (key->type == BTRFS_METADATA_ITEM_KEY &&
1037 	    !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
1038 		generic_err(leaf, slot,
1039 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1040 		return -EUCLEAN;
1041 	}
1042 	/* key->objectid is the bytenr for both key types */
1043 	if (!IS_ALIGNED(key->objectid, fs_info->sectorsize)) {
1044 		generic_err(leaf, slot,
1045 		"invalid key objectid, have %llu expect to be aligned to %u",
1046 			   key->objectid, fs_info->sectorsize);
1047 		return -EUCLEAN;
1048 	}
1049 
1050 	/* key->offset is tree level for METADATA_ITEM_KEY */
1051 	if (key->type == BTRFS_METADATA_ITEM_KEY &&
1052 	    key->offset >= BTRFS_MAX_LEVEL) {
1053 		extent_err(leaf, slot,
1054 			   "invalid tree level, have %llu expect [0, %u]",
1055 			   key->offset, BTRFS_MAX_LEVEL - 1);
1056 		return -EUCLEAN;
1057 	}
1058 
1059 	/*
1060 	 * EXTENT/METADATA_ITEM consists of:
1061 	 * 1) One btrfs_extent_item
1062 	 *    Records the total refs, type and generation of the extent.
1063 	 *
1064 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1065 	 *    Records the first key and level of the tree block.
1066 	 *
1067 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1068 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1069 	 *    2.1) The ref type, one of the 4
1070 	 *         TREE_BLOCK_REF	Tree block only
1071 	 *         SHARED_BLOCK_REF	Tree block only
1072 	 *         EXTENT_DATA_REF	Data only
1073 	 *         SHARED_DATA_REF	Data only
1074 	 *    2.2) Ref type specific data
1075 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1076 	 *         data structure.
1077 	 */
1078 	if (item_size < sizeof(*ei)) {
1079 		extent_err(leaf, slot,
1080 			   "invalid item size, have %u expect [%zu, %u)",
1081 			   item_size, sizeof(*ei),
1082 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1083 		return -EUCLEAN;
1084 	}
1085 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1086 
1087 	/* Checks against extent_item */
1088 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1089 	flags = btrfs_extent_flags(leaf, ei);
1090 	total_refs = btrfs_extent_refs(leaf, ei);
1091 	generation = btrfs_extent_generation(leaf, ei);
1092 	if (generation > btrfs_super_generation(fs_info->super_copy) + 1) {
1093 		extent_err(leaf, slot,
1094 			   "invalid generation, have %llu expect (0, %llu]",
1095 			   generation,
1096 			   btrfs_super_generation(fs_info->super_copy) + 1);
1097 		return -EUCLEAN;
1098 	}
1099 	if (!is_power_of_2(flags & (BTRFS_EXTENT_FLAG_DATA |
1100 				    BTRFS_EXTENT_FLAG_TREE_BLOCK))) {
1101 		extent_err(leaf, slot,
1102 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1103 			flags, BTRFS_EXTENT_FLAG_DATA |
1104 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1105 		return -EUCLEAN;
1106 	}
1107 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1108 	if (is_tree_block) {
1109 		if (key->type == BTRFS_EXTENT_ITEM_KEY &&
1110 		    key->offset != fs_info->nodesize) {
1111 			extent_err(leaf, slot,
1112 				   "invalid extent length, have %llu expect %u",
1113 				   key->offset, fs_info->nodesize);
1114 			return -EUCLEAN;
1115 		}
1116 	} else {
1117 		if (key->type != BTRFS_EXTENT_ITEM_KEY) {
1118 			extent_err(leaf, slot,
1119 			"invalid key type, have %u expect %u for data backref",
1120 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1121 			return -EUCLEAN;
1122 		}
1123 		if (!IS_ALIGNED(key->offset, fs_info->sectorsize)) {
1124 			extent_err(leaf, slot,
1125 			"invalid extent length, have %llu expect aligned to %u",
1126 				   key->offset, fs_info->sectorsize);
1127 			return -EUCLEAN;
1128 		}
1129 	}
1130 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1131 
1132 	/* Check the special case of btrfs_tree_block_info */
1133 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1134 		struct btrfs_tree_block_info *info;
1135 
1136 		info = (struct btrfs_tree_block_info *)ptr;
1137 		if (btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL) {
1138 			extent_err(leaf, slot,
1139 			"invalid tree block info level, have %u expect [0, %u]",
1140 				   btrfs_tree_block_level(leaf, info),
1141 				   BTRFS_MAX_LEVEL - 1);
1142 			return -EUCLEAN;
1143 		}
1144 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1145 	}
1146 
1147 	/* Check inline refs */
1148 	while (ptr < end) {
1149 		struct btrfs_extent_inline_ref *iref;
1150 		struct btrfs_extent_data_ref *dref;
1151 		struct btrfs_shared_data_ref *sref;
1152 		u64 dref_offset;
1153 		u64 inline_offset;
1154 		u8 inline_type;
1155 
1156 		if (ptr + sizeof(*iref) > end) {
1157 			extent_err(leaf, slot,
1158 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1159 				   ptr, sizeof(*iref), end);
1160 			return -EUCLEAN;
1161 		}
1162 		iref = (struct btrfs_extent_inline_ref *)ptr;
1163 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1164 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1165 		if (ptr + btrfs_extent_inline_ref_size(inline_type) > end) {
1166 			extent_err(leaf, slot,
1167 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1168 				   ptr, btrfs_extent_inline_ref_size(inline_type), end);
1169 			return -EUCLEAN;
1170 		}
1171 
1172 		switch (inline_type) {
1173 		/* inline_offset is subvolid of the owner, no need to check */
1174 		case BTRFS_TREE_BLOCK_REF_KEY:
1175 			inline_refs++;
1176 			break;
1177 		/* Contains parent bytenr */
1178 		case BTRFS_SHARED_BLOCK_REF_KEY:
1179 			if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
1180 				extent_err(leaf, slot,
1181 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1182 					   inline_offset, fs_info->sectorsize);
1183 				return -EUCLEAN;
1184 			}
1185 			inline_refs++;
1186 			break;
1187 		/*
1188 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1189 		 * The only obvious corruption can happen in that offset.
1190 		 */
1191 		case BTRFS_EXTENT_DATA_REF_KEY:
1192 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1193 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1194 			if (!IS_ALIGNED(dref_offset, fs_info->sectorsize)) {
1195 				extent_err(leaf, slot,
1196 		"invalid data ref offset, have %llu expect aligned to %u",
1197 					   dref_offset, fs_info->sectorsize);
1198 				return -EUCLEAN;
1199 			}
1200 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1201 			break;
1202 		/* Contains parent bytenr and ref count */
1203 		case BTRFS_SHARED_DATA_REF_KEY:
1204 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1205 			if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
1206 				extent_err(leaf, slot,
1207 		"invalid data parent bytenr, have %llu expect aligned to %u",
1208 					   inline_offset, fs_info->sectorsize);
1209 				return -EUCLEAN;
1210 			}
1211 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1212 			break;
1213 		default:
1214 			extent_err(leaf, slot, "unknown inline ref type: %u",
1215 				   inline_type);
1216 			return -EUCLEAN;
1217 		}
1218 		ptr += btrfs_extent_inline_ref_size(inline_type);
1219 	}
1220 	/* No padding is allowed */
1221 	if (ptr != end) {
1222 		extent_err(leaf, slot,
1223 			   "invalid extent item size, padding bytes found");
1224 		return -EUCLEAN;
1225 	}
1226 
1227 	/* Finally, check the inline refs against total refs */
1228 	if (inline_refs > total_refs) {
1229 		extent_err(leaf, slot,
1230 			"invalid extent refs, have %llu expect >= inline %llu",
1231 			   total_refs, inline_refs);
1232 		return -EUCLEAN;
1233 	}
1234 
1235 	if ((prev_key->type == BTRFS_EXTENT_ITEM_KEY) ||
1236 	    (prev_key->type == BTRFS_METADATA_ITEM_KEY)) {
1237 		u64 prev_end = prev_key->objectid;
1238 
1239 		if (prev_key->type == BTRFS_METADATA_ITEM_KEY)
1240 			prev_end += fs_info->nodesize;
1241 		else
1242 			prev_end += prev_key->offset;
1243 
1244 		if (unlikely(prev_end > key->objectid)) {
1245 			extent_err(leaf, slot,
1246 	"previous extent [%llu %u %llu] overlaps current extent [%llu %u %llu]",
1247 				   prev_key->objectid, prev_key->type,
1248 				   prev_key->offset, key->objectid, key->type,
1249 				   key->offset);
1250 			return -EUCLEAN;
1251 		}
1252 	}
1253 
1254 	return 0;
1255 }
1256 
check_simple_keyed_refs(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1257 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1258 				   struct btrfs_key *key, int slot)
1259 {
1260 	u32 expect_item_size = 0;
1261 
1262 	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1263 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1264 
1265 	if (btrfs_item_size_nr(leaf, slot) != expect_item_size) {
1266 		generic_err(leaf, slot,
1267 		"invalid item size, have %u expect %u for key type %u",
1268 			    btrfs_item_size_nr(leaf, slot),
1269 			    expect_item_size, key->type);
1270 		return -EUCLEAN;
1271 	}
1272 	if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
1273 		generic_err(leaf, slot,
1274 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1275 			    key->objectid, leaf->fs_info->sectorsize);
1276 		return -EUCLEAN;
1277 	}
1278 	if (key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1279 	    !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize)) {
1280 		extent_err(leaf, slot,
1281 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1282 			   key->offset, leaf->fs_info->sectorsize);
1283 		return -EUCLEAN;
1284 	}
1285 	return 0;
1286 }
1287 
check_extent_data_ref(struct extent_buffer * leaf,struct btrfs_key * key,int slot)1288 static int check_extent_data_ref(struct extent_buffer *leaf,
1289 				 struct btrfs_key *key, int slot)
1290 {
1291 	struct btrfs_extent_data_ref *dref;
1292 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1293 	const unsigned long end = ptr + btrfs_item_size_nr(leaf, slot);
1294 
1295 	if (btrfs_item_size_nr(leaf, slot) % sizeof(*dref) != 0) {
1296 		generic_err(leaf, slot,
1297 	"invalid item size, have %u expect aligned to %zu for key type %u",
1298 			    btrfs_item_size_nr(leaf, slot),
1299 			    sizeof(*dref), key->type);
1300 		return -EUCLEAN;
1301 	}
1302 	if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
1303 		generic_err(leaf, slot,
1304 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1305 			    key->objectid, leaf->fs_info->sectorsize);
1306 		return -EUCLEAN;
1307 	}
1308 	for (; ptr < end; ptr += sizeof(*dref)) {
1309 		u64 offset;
1310 
1311 		/*
1312 		 * We cannot check the extent_data_ref hash due to possible
1313 		 * overflow from the leaf due to hash collisions.
1314 		 */
1315 		dref = (struct btrfs_extent_data_ref *)ptr;
1316 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1317 		if (!IS_ALIGNED(offset, leaf->fs_info->sectorsize)) {
1318 			extent_err(leaf, slot,
1319 	"invalid extent data backref offset, have %llu expect aligned to %u",
1320 				   offset, leaf->fs_info->sectorsize);
1321 			return -EUCLEAN;
1322 		}
1323 	}
1324 	return 0;
1325 }
1326 
1327 /*
1328  * Common point to switch the item-specific validation.
1329  */
check_leaf_item(struct extent_buffer * leaf,struct btrfs_key * key,int slot,struct btrfs_key * prev_key)1330 static int check_leaf_item(struct extent_buffer *leaf,
1331 			   struct btrfs_key *key, int slot,
1332 			   struct btrfs_key *prev_key)
1333 {
1334 	int ret = 0;
1335 	struct btrfs_chunk *chunk;
1336 
1337 	switch (key->type) {
1338 	case BTRFS_EXTENT_DATA_KEY:
1339 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1340 		break;
1341 	case BTRFS_EXTENT_CSUM_KEY:
1342 		ret = check_csum_item(leaf, key, slot, prev_key);
1343 		break;
1344 	case BTRFS_DIR_ITEM_KEY:
1345 	case BTRFS_DIR_INDEX_KEY:
1346 	case BTRFS_XATTR_ITEM_KEY:
1347 		ret = check_dir_item(leaf, key, slot);
1348 		break;
1349 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1350 		ret = check_block_group_item(leaf, key, slot);
1351 		break;
1352 	case BTRFS_CHUNK_ITEM_KEY:
1353 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1354 		ret = check_leaf_chunk_item(leaf, chunk, key, slot);
1355 		break;
1356 	case BTRFS_DEV_ITEM_KEY:
1357 		ret = check_dev_item(leaf, key, slot);
1358 		break;
1359 	case BTRFS_INODE_ITEM_KEY:
1360 		ret = check_inode_item(leaf, key, slot);
1361 		break;
1362 	case BTRFS_ROOT_ITEM_KEY:
1363 		ret = check_root_item(leaf, key, slot);
1364 		break;
1365 	case BTRFS_EXTENT_ITEM_KEY:
1366 	case BTRFS_METADATA_ITEM_KEY:
1367 		ret = check_extent_item(leaf, key, slot, prev_key);
1368 		break;
1369 	case BTRFS_TREE_BLOCK_REF_KEY:
1370 	case BTRFS_SHARED_DATA_REF_KEY:
1371 	case BTRFS_SHARED_BLOCK_REF_KEY:
1372 		ret = check_simple_keyed_refs(leaf, key, slot);
1373 		break;
1374 	case BTRFS_EXTENT_DATA_REF_KEY:
1375 		ret = check_extent_data_ref(leaf, key, slot);
1376 		break;
1377 	}
1378 	return ret;
1379 }
1380 
check_leaf(struct extent_buffer * leaf,bool check_item_data)1381 static int check_leaf(struct extent_buffer *leaf, bool check_item_data)
1382 {
1383 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1384 	/* No valid key type is 0, so all key should be larger than this key */
1385 	struct btrfs_key prev_key = {0, 0, 0};
1386 	struct btrfs_key key;
1387 	u32 nritems = btrfs_header_nritems(leaf);
1388 	int slot;
1389 
1390 	if (btrfs_header_level(leaf) != 0) {
1391 		generic_err(leaf, 0,
1392 			"invalid level for leaf, have %d expect 0",
1393 			btrfs_header_level(leaf));
1394 		return -EUCLEAN;
1395 	}
1396 
1397 	/*
1398 	 * Extent buffers from a relocation tree have a owner field that
1399 	 * corresponds to the subvolume tree they are based on. So just from an
1400 	 * extent buffer alone we can not find out what is the id of the
1401 	 * corresponding subvolume tree, so we can not figure out if the extent
1402 	 * buffer corresponds to the root of the relocation tree or not. So
1403 	 * skip this check for relocation trees.
1404 	 */
1405 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1406 		u64 owner = btrfs_header_owner(leaf);
1407 
1408 		/* These trees must never be empty */
1409 		if (owner == BTRFS_ROOT_TREE_OBJECTID ||
1410 		    owner == BTRFS_CHUNK_TREE_OBJECTID ||
1411 		    owner == BTRFS_EXTENT_TREE_OBJECTID ||
1412 		    owner == BTRFS_DEV_TREE_OBJECTID ||
1413 		    owner == BTRFS_FS_TREE_OBJECTID ||
1414 		    owner == BTRFS_DATA_RELOC_TREE_OBJECTID) {
1415 			generic_err(leaf, 0,
1416 			"invalid root, root %llu must never be empty",
1417 				    owner);
1418 			return -EUCLEAN;
1419 		}
1420 		/* Unknown tree */
1421 		if (owner == 0) {
1422 			generic_err(leaf, 0,
1423 				"invalid owner, root 0 is not defined");
1424 			return -EUCLEAN;
1425 		}
1426 		return 0;
1427 	}
1428 
1429 	if (nritems == 0)
1430 		return 0;
1431 
1432 	/*
1433 	 * Check the following things to make sure this is a good leaf, and
1434 	 * leaf users won't need to bother with similar sanity checks:
1435 	 *
1436 	 * 1) key ordering
1437 	 * 2) item offset and size
1438 	 *    No overlap, no hole, all inside the leaf.
1439 	 * 3) item content
1440 	 *    If possible, do comprehensive sanity check.
1441 	 *    NOTE: All checks must only rely on the item data itself.
1442 	 */
1443 	for (slot = 0; slot < nritems; slot++) {
1444 		u32 item_end_expected;
1445 		int ret;
1446 
1447 		btrfs_item_key_to_cpu(leaf, &key, slot);
1448 
1449 		/* Make sure the keys are in the right order */
1450 		if (btrfs_comp_cpu_keys(&prev_key, &key) >= 0) {
1451 			generic_err(leaf, slot,
1452 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1453 				prev_key.objectid, prev_key.type,
1454 				prev_key.offset, key.objectid, key.type,
1455 				key.offset);
1456 			return -EUCLEAN;
1457 		}
1458 
1459 		/*
1460 		 * Make sure the offset and ends are right, remember that the
1461 		 * item data starts at the end of the leaf and grows towards the
1462 		 * front.
1463 		 */
1464 		if (slot == 0)
1465 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1466 		else
1467 			item_end_expected = btrfs_item_offset_nr(leaf,
1468 								 slot - 1);
1469 		if (btrfs_item_end_nr(leaf, slot) != item_end_expected) {
1470 			generic_err(leaf, slot,
1471 				"unexpected item end, have %u expect %u",
1472 				btrfs_item_end_nr(leaf, slot),
1473 				item_end_expected);
1474 			return -EUCLEAN;
1475 		}
1476 
1477 		/*
1478 		 * Check to make sure that we don't point outside of the leaf,
1479 		 * just in case all the items are consistent to each other, but
1480 		 * all point outside of the leaf.
1481 		 */
1482 		if (btrfs_item_end_nr(leaf, slot) >
1483 		    BTRFS_LEAF_DATA_SIZE(fs_info)) {
1484 			generic_err(leaf, slot,
1485 			"slot end outside of leaf, have %u expect range [0, %u]",
1486 				btrfs_item_end_nr(leaf, slot),
1487 				BTRFS_LEAF_DATA_SIZE(fs_info));
1488 			return -EUCLEAN;
1489 		}
1490 
1491 		/* Also check if the item pointer overlaps with btrfs item. */
1492 		if (btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item) >
1493 		    btrfs_item_ptr_offset(leaf, slot)) {
1494 			generic_err(leaf, slot,
1495 		"slot overlaps with its data, item end %lu data start %lu",
1496 				btrfs_item_nr_offset(slot) +
1497 				sizeof(struct btrfs_item),
1498 				btrfs_item_ptr_offset(leaf, slot));
1499 			return -EUCLEAN;
1500 		}
1501 
1502 		if (check_item_data) {
1503 			/*
1504 			 * Check if the item size and content meet other
1505 			 * criteria
1506 			 */
1507 			ret = check_leaf_item(leaf, &key, slot, &prev_key);
1508 			if (ret < 0)
1509 				return ret;
1510 		}
1511 
1512 		prev_key.objectid = key.objectid;
1513 		prev_key.type = key.type;
1514 		prev_key.offset = key.offset;
1515 	}
1516 
1517 	return 0;
1518 }
1519 
btrfs_check_leaf_full(struct extent_buffer * leaf)1520 int btrfs_check_leaf_full(struct extent_buffer *leaf)
1521 {
1522 	return check_leaf(leaf, true);
1523 }
1524 ALLOW_ERROR_INJECTION(btrfs_check_leaf_full, ERRNO);
1525 
btrfs_check_leaf_relaxed(struct extent_buffer * leaf)1526 int btrfs_check_leaf_relaxed(struct extent_buffer *leaf)
1527 {
1528 	return check_leaf(leaf, false);
1529 }
1530 
btrfs_check_node(struct extent_buffer * node)1531 int btrfs_check_node(struct extent_buffer *node)
1532 {
1533 	struct btrfs_fs_info *fs_info = node->fs_info;
1534 	unsigned long nr = btrfs_header_nritems(node);
1535 	struct btrfs_key key, next_key;
1536 	int slot;
1537 	int level = btrfs_header_level(node);
1538 	u64 bytenr;
1539 	int ret = 0;
1540 
1541 	if (level <= 0 || level >= BTRFS_MAX_LEVEL) {
1542 		generic_err(node, 0,
1543 			"invalid level for node, have %d expect [1, %d]",
1544 			level, BTRFS_MAX_LEVEL - 1);
1545 		return -EUCLEAN;
1546 	}
1547 	if (nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info)) {
1548 		btrfs_crit(fs_info,
1549 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1550 			   btrfs_header_owner(node), node->start,
1551 			   nr == 0 ? "small" : "large", nr,
1552 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1553 		return -EUCLEAN;
1554 	}
1555 
1556 	for (slot = 0; slot < nr - 1; slot++) {
1557 		bytenr = btrfs_node_blockptr(node, slot);
1558 		btrfs_node_key_to_cpu(node, &key, slot);
1559 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1560 
1561 		if (!bytenr) {
1562 			generic_err(node, slot,
1563 				"invalid NULL node pointer");
1564 			ret = -EUCLEAN;
1565 			goto out;
1566 		}
1567 		if (!IS_ALIGNED(bytenr, fs_info->sectorsize)) {
1568 			generic_err(node, slot,
1569 			"unaligned pointer, have %llu should be aligned to %u",
1570 				bytenr, fs_info->sectorsize);
1571 			ret = -EUCLEAN;
1572 			goto out;
1573 		}
1574 
1575 		if (btrfs_comp_cpu_keys(&key, &next_key) >= 0) {
1576 			generic_err(node, slot,
1577 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1578 				key.objectid, key.type, key.offset,
1579 				next_key.objectid, next_key.type,
1580 				next_key.offset);
1581 			ret = -EUCLEAN;
1582 			goto out;
1583 		}
1584 	}
1585 out:
1586 	return ret;
1587 }
1588 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
1589