xref: /openbmc/linux/fs/btrfs/tree-checker.c (revision 5a158981)
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 
28 /*
29  * Error message should follow the following format:
30  * corrupt <type>: <identifier>, <reason>[, <bad_value>]
31  *
32  * @type:	leaf or node
33  * @identifier:	the necessary info to locate the leaf/node.
34  * 		It's recommended to decode key.objecitd/offset if it's
35  * 		meaningful.
36  * @reason:	describe the error
37  * @bad_value:	optional, it's recommended to output bad value and its
38  *		expected value (range).
39  *
40  * Since comma is used to separate the components, only space is allowed
41  * inside each component.
42  */
43 
44 /*
45  * Append generic "corrupt leaf/node root=%llu block=%llu slot=%d: " to @fmt.
46  * Allows callers to customize the output.
47  */
48 __printf(3, 4)
49 __cold
50 static void generic_err(const struct extent_buffer *eb, int slot,
51 			const char *fmt, ...)
52 {
53 	const struct btrfs_fs_info *fs_info = eb->fs_info;
54 	struct va_format vaf;
55 	va_list args;
56 
57 	va_start(args, fmt);
58 
59 	vaf.fmt = fmt;
60 	vaf.va = &args;
61 
62 	btrfs_crit(fs_info,
63 		"corrupt %s: root=%llu block=%llu slot=%d, %pV",
64 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
65 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot, &vaf);
66 	va_end(args);
67 }
68 
69 /*
70  * Customized reporter for extent data item, since its key objectid and
71  * offset has its own meaning.
72  */
73 __printf(3, 4)
74 __cold
75 static void file_extent_err(const struct extent_buffer *eb, int slot,
76 			    const char *fmt, ...)
77 {
78 	const struct btrfs_fs_info *fs_info = eb->fs_info;
79 	struct btrfs_key key;
80 	struct va_format vaf;
81 	va_list args;
82 
83 	btrfs_item_key_to_cpu(eb, &key, slot);
84 	va_start(args, fmt);
85 
86 	vaf.fmt = fmt;
87 	vaf.va = &args;
88 
89 	btrfs_crit(fs_info,
90 	"corrupt %s: root=%llu block=%llu slot=%d ino=%llu file_offset=%llu, %pV",
91 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
92 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
93 		key.objectid, key.offset, &vaf);
94 	va_end(args);
95 }
96 
97 /*
98  * Return 0 if the btrfs_file_extent_##name is aligned to @alignment
99  * Else return 1
100  */
101 #define CHECK_FE_ALIGNED(leaf, slot, fi, name, alignment)		      \
102 ({									      \
103 	if (!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment))) \
104 		file_extent_err((leaf), (slot),				      \
105 	"invalid %s for file extent, have %llu, should be aligned to %u",     \
106 			(#name), btrfs_file_extent_##name((leaf), (fi)),      \
107 			(alignment));					      \
108 	(!IS_ALIGNED(btrfs_file_extent_##name((leaf), (fi)), (alignment)));   \
109 })
110 
111 static u64 file_extent_end(struct extent_buffer *leaf,
112 			   struct btrfs_key *key,
113 			   struct btrfs_file_extent_item *extent)
114 {
115 	u64 end;
116 	u64 len;
117 
118 	if (btrfs_file_extent_type(leaf, extent) == BTRFS_FILE_EXTENT_INLINE) {
119 		len = btrfs_file_extent_ram_bytes(leaf, extent);
120 		end = ALIGN(key->offset + len, leaf->fs_info->sectorsize);
121 	} else {
122 		len = btrfs_file_extent_num_bytes(leaf, extent);
123 		end = key->offset + len;
124 	}
125 	return end;
126 }
127 
128 /*
129  * Customized report for dir_item, the only new important information is
130  * key->objectid, which represents inode number
131  */
132 __printf(3, 4)
133 __cold
134 static void dir_item_err(const struct extent_buffer *eb, int slot,
135 			 const char *fmt, ...)
136 {
137 	const struct btrfs_fs_info *fs_info = eb->fs_info;
138 	struct btrfs_key key;
139 	struct va_format vaf;
140 	va_list args;
141 
142 	btrfs_item_key_to_cpu(eb, &key, slot);
143 	va_start(args, fmt);
144 
145 	vaf.fmt = fmt;
146 	vaf.va = &args;
147 
148 	btrfs_crit(fs_info,
149 		"corrupt %s: root=%llu block=%llu slot=%d ino=%llu, %pV",
150 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
151 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
152 		key.objectid, &vaf);
153 	va_end(args);
154 }
155 
156 /*
157  * This functions checks prev_key->objectid, to ensure current key and prev_key
158  * share the same objectid as inode number.
159  *
160  * This is to detect missing INODE_ITEM in subvolume trees.
161  *
162  * Return true if everything is OK or we don't need to check.
163  * Return false if anything is wrong.
164  */
165 static bool check_prev_ino(struct extent_buffer *leaf,
166 			   struct btrfs_key *key, int slot,
167 			   struct btrfs_key *prev_key)
168 {
169 	/* No prev key, skip check */
170 	if (slot == 0)
171 		return true;
172 
173 	/* Only these key->types needs to be checked */
174 	ASSERT(key->type == BTRFS_XATTR_ITEM_KEY ||
175 	       key->type == BTRFS_INODE_REF_KEY ||
176 	       key->type == BTRFS_DIR_INDEX_KEY ||
177 	       key->type == BTRFS_DIR_ITEM_KEY ||
178 	       key->type == BTRFS_EXTENT_DATA_KEY);
179 
180 	/*
181 	 * Only subvolume trees along with their reloc trees need this check.
182 	 * Things like log tree doesn't follow this ino requirement.
183 	 */
184 	if (!is_fstree(btrfs_header_owner(leaf)))
185 		return true;
186 
187 	if (key->objectid == prev_key->objectid)
188 		return true;
189 
190 	/* Error found */
191 	dir_item_err(leaf, slot,
192 		"invalid previous key objectid, have %llu expect %llu",
193 		prev_key->objectid, key->objectid);
194 	return false;
195 }
196 static int check_extent_data_item(struct extent_buffer *leaf,
197 				  struct btrfs_key *key, int slot,
198 				  struct btrfs_key *prev_key)
199 {
200 	struct btrfs_fs_info *fs_info = leaf->fs_info;
201 	struct btrfs_file_extent_item *fi;
202 	u32 sectorsize = fs_info->sectorsize;
203 	u32 item_size = btrfs_item_size_nr(leaf, slot);
204 	u64 extent_end;
205 
206 	if (!IS_ALIGNED(key->offset, sectorsize)) {
207 		file_extent_err(leaf, slot,
208 "unaligned file_offset for file extent, have %llu should be aligned to %u",
209 			key->offset, sectorsize);
210 		return -EUCLEAN;
211 	}
212 
213 	/*
214 	 * Previous key must have the same key->objectid (ino).
215 	 * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA.
216 	 * But if objectids mismatch, it means we have a missing
217 	 * INODE_ITEM.
218 	 */
219 	if (!check_prev_ino(leaf, key, slot, prev_key))
220 		return -EUCLEAN;
221 
222 	fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
223 
224 	/*
225 	 * Make sure the item contains at least inline header, so the file
226 	 * extent type is not some garbage.
227 	 */
228 	if (item_size < BTRFS_FILE_EXTENT_INLINE_DATA_START) {
229 		file_extent_err(leaf, slot,
230 				"invalid item size, have %u expect [%zu, %u)",
231 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START,
232 				SZ_4K);
233 		return -EUCLEAN;
234 	}
235 	if (btrfs_file_extent_type(leaf, fi) >= BTRFS_NR_FILE_EXTENT_TYPES) {
236 		file_extent_err(leaf, slot,
237 		"invalid type for file extent, have %u expect range [0, %u]",
238 			btrfs_file_extent_type(leaf, fi),
239 			BTRFS_NR_FILE_EXTENT_TYPES - 1);
240 		return -EUCLEAN;
241 	}
242 
243 	/*
244 	 * Support for new compression/encryption must introduce incompat flag,
245 	 * and must be caught in open_ctree().
246 	 */
247 	if (btrfs_file_extent_compression(leaf, fi) >= BTRFS_NR_COMPRESS_TYPES) {
248 		file_extent_err(leaf, slot,
249 	"invalid compression for file extent, have %u expect range [0, %u]",
250 			btrfs_file_extent_compression(leaf, fi),
251 			BTRFS_NR_COMPRESS_TYPES - 1);
252 		return -EUCLEAN;
253 	}
254 	if (btrfs_file_extent_encryption(leaf, fi)) {
255 		file_extent_err(leaf, slot,
256 			"invalid encryption for file extent, have %u expect 0",
257 			btrfs_file_extent_encryption(leaf, fi));
258 		return -EUCLEAN;
259 	}
260 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
261 		/* Inline extent must have 0 as key offset */
262 		if (key->offset) {
263 			file_extent_err(leaf, slot,
264 		"invalid file_offset for inline file extent, have %llu expect 0",
265 				key->offset);
266 			return -EUCLEAN;
267 		}
268 
269 		/* Compressed inline extent has no on-disk size, skip it */
270 		if (btrfs_file_extent_compression(leaf, fi) !=
271 		    BTRFS_COMPRESS_NONE)
272 			return 0;
273 
274 		/* Uncompressed inline extent size must match item size */
275 		if (item_size != BTRFS_FILE_EXTENT_INLINE_DATA_START +
276 		    btrfs_file_extent_ram_bytes(leaf, fi)) {
277 			file_extent_err(leaf, slot,
278 	"invalid ram_bytes for uncompressed inline extent, have %u expect %llu",
279 				item_size, BTRFS_FILE_EXTENT_INLINE_DATA_START +
280 				btrfs_file_extent_ram_bytes(leaf, fi));
281 			return -EUCLEAN;
282 		}
283 		return 0;
284 	}
285 
286 	/* Regular or preallocated extent has fixed item size */
287 	if (item_size != sizeof(*fi)) {
288 		file_extent_err(leaf, slot,
289 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
290 			item_size, sizeof(*fi));
291 		return -EUCLEAN;
292 	}
293 	if (CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
294 	    CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
295 	    CHECK_FE_ALIGNED(leaf, slot, fi, disk_num_bytes, sectorsize) ||
296 	    CHECK_FE_ALIGNED(leaf, slot, fi, offset, sectorsize) ||
297 	    CHECK_FE_ALIGNED(leaf, slot, fi, num_bytes, sectorsize))
298 		return -EUCLEAN;
299 
300 	/* Catch extent end overflow */
301 	if (check_add_overflow(btrfs_file_extent_num_bytes(leaf, fi),
302 			       key->offset, &extent_end)) {
303 		file_extent_err(leaf, slot,
304 	"extent end overflow, have file offset %llu extent num bytes %llu",
305 				key->offset,
306 				btrfs_file_extent_num_bytes(leaf, fi));
307 		return -EUCLEAN;
308 	}
309 
310 	/*
311 	 * Check that no two consecutive file extent items, in the same leaf,
312 	 * present ranges that overlap each other.
313 	 */
314 	if (slot > 0 &&
315 	    prev_key->objectid == key->objectid &&
316 	    prev_key->type == BTRFS_EXTENT_DATA_KEY) {
317 		struct btrfs_file_extent_item *prev_fi;
318 		u64 prev_end;
319 
320 		prev_fi = btrfs_item_ptr(leaf, slot - 1,
321 					 struct btrfs_file_extent_item);
322 		prev_end = file_extent_end(leaf, prev_key, prev_fi);
323 		if (prev_end > key->offset) {
324 			file_extent_err(leaf, slot - 1,
325 "file extent end range (%llu) goes beyond start offset (%llu) of the next file extent",
326 					prev_end, key->offset);
327 			return -EUCLEAN;
328 		}
329 	}
330 
331 	return 0;
332 }
333 
334 static int check_csum_item(struct extent_buffer *leaf, struct btrfs_key *key,
335 			   int slot, struct btrfs_key *prev_key)
336 {
337 	struct btrfs_fs_info *fs_info = leaf->fs_info;
338 	u32 sectorsize = fs_info->sectorsize;
339 	u32 csumsize = btrfs_super_csum_size(fs_info->super_copy);
340 
341 	if (key->objectid != BTRFS_EXTENT_CSUM_OBJECTID) {
342 		generic_err(leaf, slot,
343 		"invalid key objectid for csum item, have %llu expect %llu",
344 			key->objectid, BTRFS_EXTENT_CSUM_OBJECTID);
345 		return -EUCLEAN;
346 	}
347 	if (!IS_ALIGNED(key->offset, sectorsize)) {
348 		generic_err(leaf, slot,
349 	"unaligned key offset for csum item, have %llu should be aligned to %u",
350 			key->offset, sectorsize);
351 		return -EUCLEAN;
352 	}
353 	if (!IS_ALIGNED(btrfs_item_size_nr(leaf, slot), csumsize)) {
354 		generic_err(leaf, slot,
355 	"unaligned item size for csum item, have %u should be aligned to %u",
356 			btrfs_item_size_nr(leaf, slot), csumsize);
357 		return -EUCLEAN;
358 	}
359 	if (slot > 0 && prev_key->type == BTRFS_EXTENT_CSUM_KEY) {
360 		u64 prev_csum_end;
361 		u32 prev_item_size;
362 
363 		prev_item_size = btrfs_item_size_nr(leaf, slot - 1);
364 		prev_csum_end = (prev_item_size / csumsize) * sectorsize;
365 		prev_csum_end += prev_key->offset;
366 		if (prev_csum_end > key->offset) {
367 			generic_err(leaf, slot - 1,
368 "csum end range (%llu) goes beyond the start range (%llu) of the next csum item",
369 				    prev_csum_end, key->offset);
370 			return -EUCLEAN;
371 		}
372 	}
373 	return 0;
374 }
375 
376 static int check_dir_item(struct extent_buffer *leaf,
377 			  struct btrfs_key *key, struct btrfs_key *prev_key,
378 			  int slot)
379 {
380 	struct btrfs_fs_info *fs_info = leaf->fs_info;
381 	struct btrfs_dir_item *di;
382 	u32 item_size = btrfs_item_size_nr(leaf, slot);
383 	u32 cur = 0;
384 
385 	if (!check_prev_ino(leaf, key, slot, prev_key))
386 		return -EUCLEAN;
387 	di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
388 	while (cur < item_size) {
389 		u32 name_len;
390 		u32 data_len;
391 		u32 max_name_len;
392 		u32 total_size;
393 		u32 name_hash;
394 		u8 dir_type;
395 
396 		/* header itself should not cross item boundary */
397 		if (cur + sizeof(*di) > item_size) {
398 			dir_item_err(leaf, slot,
399 		"dir item header crosses item boundary, have %zu boundary %u",
400 				cur + sizeof(*di), item_size);
401 			return -EUCLEAN;
402 		}
403 
404 		/* dir type check */
405 		dir_type = btrfs_dir_type(leaf, di);
406 		if (dir_type >= BTRFS_FT_MAX) {
407 			dir_item_err(leaf, slot,
408 			"invalid dir item type, have %u expect [0, %u)",
409 				dir_type, BTRFS_FT_MAX);
410 			return -EUCLEAN;
411 		}
412 
413 		if (key->type == BTRFS_XATTR_ITEM_KEY &&
414 		    dir_type != BTRFS_FT_XATTR) {
415 			dir_item_err(leaf, slot,
416 		"invalid dir item type for XATTR key, have %u expect %u",
417 				dir_type, BTRFS_FT_XATTR);
418 			return -EUCLEAN;
419 		}
420 		if (dir_type == BTRFS_FT_XATTR &&
421 		    key->type != BTRFS_XATTR_ITEM_KEY) {
422 			dir_item_err(leaf, slot,
423 			"xattr dir type found for non-XATTR key");
424 			return -EUCLEAN;
425 		}
426 		if (dir_type == BTRFS_FT_XATTR)
427 			max_name_len = XATTR_NAME_MAX;
428 		else
429 			max_name_len = BTRFS_NAME_LEN;
430 
431 		/* Name/data length check */
432 		name_len = btrfs_dir_name_len(leaf, di);
433 		data_len = btrfs_dir_data_len(leaf, di);
434 		if (name_len > max_name_len) {
435 			dir_item_err(leaf, slot,
436 			"dir item name len too long, have %u max %u",
437 				name_len, max_name_len);
438 			return -EUCLEAN;
439 		}
440 		if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(fs_info)) {
441 			dir_item_err(leaf, slot,
442 			"dir item name and data len too long, have %u max %u",
443 				name_len + data_len,
444 				BTRFS_MAX_XATTR_SIZE(fs_info));
445 			return -EUCLEAN;
446 		}
447 
448 		if (data_len && dir_type != BTRFS_FT_XATTR) {
449 			dir_item_err(leaf, slot,
450 			"dir item with invalid data len, have %u expect 0",
451 				data_len);
452 			return -EUCLEAN;
453 		}
454 
455 		total_size = sizeof(*di) + name_len + data_len;
456 
457 		/* header and name/data should not cross item boundary */
458 		if (cur + total_size > item_size) {
459 			dir_item_err(leaf, slot,
460 		"dir item data crosses item boundary, have %u boundary %u",
461 				cur + total_size, item_size);
462 			return -EUCLEAN;
463 		}
464 
465 		/*
466 		 * Special check for XATTR/DIR_ITEM, as key->offset is name
467 		 * hash, should match its name
468 		 */
469 		if (key->type == BTRFS_DIR_ITEM_KEY ||
470 		    key->type == BTRFS_XATTR_ITEM_KEY) {
471 			char namebuf[max(BTRFS_NAME_LEN, XATTR_NAME_MAX)];
472 
473 			read_extent_buffer(leaf, namebuf,
474 					(unsigned long)(di + 1), name_len);
475 			name_hash = btrfs_name_hash(namebuf, name_len);
476 			if (key->offset != name_hash) {
477 				dir_item_err(leaf, slot,
478 		"name hash mismatch with key, have 0x%016x expect 0x%016llx",
479 					name_hash, key->offset);
480 				return -EUCLEAN;
481 			}
482 		}
483 		cur += total_size;
484 		di = (struct btrfs_dir_item *)((void *)di + total_size);
485 	}
486 	return 0;
487 }
488 
489 __printf(3, 4)
490 __cold
491 static void block_group_err(const struct extent_buffer *eb, int slot,
492 			    const char *fmt, ...)
493 {
494 	const struct btrfs_fs_info *fs_info = eb->fs_info;
495 	struct btrfs_key key;
496 	struct va_format vaf;
497 	va_list args;
498 
499 	btrfs_item_key_to_cpu(eb, &key, slot);
500 	va_start(args, fmt);
501 
502 	vaf.fmt = fmt;
503 	vaf.va = &args;
504 
505 	btrfs_crit(fs_info,
506 	"corrupt %s: root=%llu block=%llu slot=%d bg_start=%llu bg_len=%llu, %pV",
507 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
508 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
509 		key.objectid, key.offset, &vaf);
510 	va_end(args);
511 }
512 
513 static int check_block_group_item(struct extent_buffer *leaf,
514 				  struct btrfs_key *key, int slot)
515 {
516 	struct btrfs_block_group_item bgi;
517 	u32 item_size = btrfs_item_size_nr(leaf, slot);
518 	u64 flags;
519 	u64 type;
520 
521 	/*
522 	 * Here we don't really care about alignment since extent allocator can
523 	 * handle it.  We care more about the size.
524 	 */
525 	if (key->offset == 0) {
526 		block_group_err(leaf, slot,
527 				"invalid block group size 0");
528 		return -EUCLEAN;
529 	}
530 
531 	if (item_size != sizeof(bgi)) {
532 		block_group_err(leaf, slot,
533 			"invalid item size, have %u expect %zu",
534 				item_size, sizeof(bgi));
535 		return -EUCLEAN;
536 	}
537 
538 	read_extent_buffer(leaf, &bgi, btrfs_item_ptr_offset(leaf, slot),
539 			   sizeof(bgi));
540 	if (btrfs_stack_block_group_chunk_objectid(&bgi) !=
541 	    BTRFS_FIRST_CHUNK_TREE_OBJECTID) {
542 		block_group_err(leaf, slot,
543 		"invalid block group chunk objectid, have %llu expect %llu",
544 				btrfs_stack_block_group_chunk_objectid(&bgi),
545 				BTRFS_FIRST_CHUNK_TREE_OBJECTID);
546 		return -EUCLEAN;
547 	}
548 
549 	if (btrfs_stack_block_group_used(&bgi) > key->offset) {
550 		block_group_err(leaf, slot,
551 			"invalid block group used, have %llu expect [0, %llu)",
552 				btrfs_stack_block_group_used(&bgi), key->offset);
553 		return -EUCLEAN;
554 	}
555 
556 	flags = btrfs_stack_block_group_flags(&bgi);
557 	if (hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) > 1) {
558 		block_group_err(leaf, slot,
559 "invalid profile flags, have 0x%llx (%lu bits set) expect no more than 1 bit set",
560 			flags & BTRFS_BLOCK_GROUP_PROFILE_MASK,
561 			hweight64(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK));
562 		return -EUCLEAN;
563 	}
564 
565 	type = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
566 	if (type != BTRFS_BLOCK_GROUP_DATA &&
567 	    type != BTRFS_BLOCK_GROUP_METADATA &&
568 	    type != BTRFS_BLOCK_GROUP_SYSTEM &&
569 	    type != (BTRFS_BLOCK_GROUP_METADATA |
570 			   BTRFS_BLOCK_GROUP_DATA)) {
571 		block_group_err(leaf, slot,
572 "invalid type, have 0x%llx (%lu bits set) expect either 0x%llx, 0x%llx, 0x%llx or 0x%llx",
573 			type, hweight64(type),
574 			BTRFS_BLOCK_GROUP_DATA, BTRFS_BLOCK_GROUP_METADATA,
575 			BTRFS_BLOCK_GROUP_SYSTEM,
576 			BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA);
577 		return -EUCLEAN;
578 	}
579 	return 0;
580 }
581 
582 __printf(4, 5)
583 __cold
584 static void chunk_err(const struct extent_buffer *leaf,
585 		      const struct btrfs_chunk *chunk, u64 logical,
586 		      const char *fmt, ...)
587 {
588 	const struct btrfs_fs_info *fs_info = leaf->fs_info;
589 	bool is_sb;
590 	struct va_format vaf;
591 	va_list args;
592 	int i;
593 	int slot = -1;
594 
595 	/* Only superblock eb is able to have such small offset */
596 	is_sb = (leaf->start == BTRFS_SUPER_INFO_OFFSET);
597 
598 	if (!is_sb) {
599 		/*
600 		 * Get the slot number by iterating through all slots, this
601 		 * would provide better readability.
602 		 */
603 		for (i = 0; i < btrfs_header_nritems(leaf); i++) {
604 			if (btrfs_item_ptr_offset(leaf, i) ==
605 					(unsigned long)chunk) {
606 				slot = i;
607 				break;
608 			}
609 		}
610 	}
611 	va_start(args, fmt);
612 	vaf.fmt = fmt;
613 	vaf.va = &args;
614 
615 	if (is_sb)
616 		btrfs_crit(fs_info,
617 		"corrupt superblock syschunk array: chunk_start=%llu, %pV",
618 			   logical, &vaf);
619 	else
620 		btrfs_crit(fs_info,
621 	"corrupt leaf: root=%llu block=%llu slot=%d chunk_start=%llu, %pV",
622 			   BTRFS_CHUNK_TREE_OBJECTID, leaf->start, slot,
623 			   logical, &vaf);
624 	va_end(args);
625 }
626 
627 /*
628  * The common chunk check which could also work on super block sys chunk array.
629  *
630  * Return -EUCLEAN if anything is corrupted.
631  * Return 0 if everything is OK.
632  */
633 int btrfs_check_chunk_valid(struct extent_buffer *leaf,
634 			    struct btrfs_chunk *chunk, u64 logical)
635 {
636 	struct btrfs_fs_info *fs_info = leaf->fs_info;
637 	u64 length;
638 	u64 stripe_len;
639 	u16 num_stripes;
640 	u16 sub_stripes;
641 	u64 type;
642 	u64 features;
643 	bool mixed = false;
644 
645 	length = btrfs_chunk_length(leaf, chunk);
646 	stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
647 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
648 	sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
649 	type = btrfs_chunk_type(leaf, chunk);
650 
651 	if (!num_stripes) {
652 		chunk_err(leaf, chunk, logical,
653 			  "invalid chunk num_stripes, have %u", num_stripes);
654 		return -EUCLEAN;
655 	}
656 	if (!IS_ALIGNED(logical, fs_info->sectorsize)) {
657 		chunk_err(leaf, chunk, logical,
658 		"invalid chunk logical, have %llu should aligned to %u",
659 			  logical, fs_info->sectorsize);
660 		return -EUCLEAN;
661 	}
662 	if (btrfs_chunk_sector_size(leaf, chunk) != fs_info->sectorsize) {
663 		chunk_err(leaf, chunk, logical,
664 			  "invalid chunk sectorsize, have %u expect %u",
665 			  btrfs_chunk_sector_size(leaf, chunk),
666 			  fs_info->sectorsize);
667 		return -EUCLEAN;
668 	}
669 	if (!length || !IS_ALIGNED(length, fs_info->sectorsize)) {
670 		chunk_err(leaf, chunk, logical,
671 			  "invalid chunk length, have %llu", length);
672 		return -EUCLEAN;
673 	}
674 	if (!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN) {
675 		chunk_err(leaf, chunk, logical,
676 			  "invalid chunk stripe length: %llu",
677 			  stripe_len);
678 		return -EUCLEAN;
679 	}
680 	if (~(BTRFS_BLOCK_GROUP_TYPE_MASK | BTRFS_BLOCK_GROUP_PROFILE_MASK) &
681 	    type) {
682 		chunk_err(leaf, chunk, logical,
683 			  "unrecognized chunk type: 0x%llx",
684 			  ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
685 			    BTRFS_BLOCK_GROUP_PROFILE_MASK) &
686 			  btrfs_chunk_type(leaf, chunk));
687 		return -EUCLEAN;
688 	}
689 
690 	if (!has_single_bit_set(type & BTRFS_BLOCK_GROUP_PROFILE_MASK) &&
691 	    (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) != 0) {
692 		chunk_err(leaf, chunk, logical,
693 		"invalid chunk profile flag: 0x%llx, expect 0 or 1 bit set",
694 			  type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
695 		return -EUCLEAN;
696 	}
697 	if ((type & BTRFS_BLOCK_GROUP_TYPE_MASK) == 0) {
698 		chunk_err(leaf, chunk, logical,
699 	"missing chunk type flag, have 0x%llx one bit must be set in 0x%llx",
700 			  type, BTRFS_BLOCK_GROUP_TYPE_MASK);
701 		return -EUCLEAN;
702 	}
703 
704 	if ((type & BTRFS_BLOCK_GROUP_SYSTEM) &&
705 	    (type & (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA))) {
706 		chunk_err(leaf, chunk, logical,
707 			  "system chunk with data or metadata type: 0x%llx",
708 			  type);
709 		return -EUCLEAN;
710 	}
711 
712 	features = btrfs_super_incompat_flags(fs_info->super_copy);
713 	if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
714 		mixed = true;
715 
716 	if (!mixed) {
717 		if ((type & BTRFS_BLOCK_GROUP_METADATA) &&
718 		    (type & BTRFS_BLOCK_GROUP_DATA)) {
719 			chunk_err(leaf, chunk, logical,
720 			"mixed chunk type in non-mixed mode: 0x%llx", type);
721 			return -EUCLEAN;
722 		}
723 	}
724 
725 	if ((type & BTRFS_BLOCK_GROUP_RAID10 && sub_stripes != 2) ||
726 	    (type & BTRFS_BLOCK_GROUP_RAID1 && num_stripes != 2) ||
727 	    (type & BTRFS_BLOCK_GROUP_RAID5 && num_stripes < 2) ||
728 	    (type & BTRFS_BLOCK_GROUP_RAID6 && num_stripes < 3) ||
729 	    (type & BTRFS_BLOCK_GROUP_DUP && num_stripes != 2) ||
730 	    ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 && num_stripes != 1)) {
731 		chunk_err(leaf, chunk, logical,
732 			"invalid num_stripes:sub_stripes %u:%u for profile %llu",
733 			num_stripes, sub_stripes,
734 			type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
735 		return -EUCLEAN;
736 	}
737 
738 	return 0;
739 }
740 
741 __printf(3, 4)
742 __cold
743 static void dev_item_err(const struct extent_buffer *eb, int slot,
744 			 const char *fmt, ...)
745 {
746 	struct btrfs_key key;
747 	struct va_format vaf;
748 	va_list args;
749 
750 	btrfs_item_key_to_cpu(eb, &key, slot);
751 	va_start(args, fmt);
752 
753 	vaf.fmt = fmt;
754 	vaf.va = &args;
755 
756 	btrfs_crit(eb->fs_info,
757 	"corrupt %s: root=%llu block=%llu slot=%d devid=%llu %pV",
758 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
759 		btrfs_header_owner(eb), btrfs_header_bytenr(eb), slot,
760 		key.objectid, &vaf);
761 	va_end(args);
762 }
763 
764 static int check_dev_item(struct extent_buffer *leaf,
765 			  struct btrfs_key *key, int slot)
766 {
767 	struct btrfs_dev_item *ditem;
768 
769 	if (key->objectid != BTRFS_DEV_ITEMS_OBJECTID) {
770 		dev_item_err(leaf, slot,
771 			     "invalid objectid: has=%llu expect=%llu",
772 			     key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
773 		return -EUCLEAN;
774 	}
775 	ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
776 	if (btrfs_device_id(leaf, ditem) != key->offset) {
777 		dev_item_err(leaf, slot,
778 			     "devid mismatch: key has=%llu item has=%llu",
779 			     key->offset, btrfs_device_id(leaf, ditem));
780 		return -EUCLEAN;
781 	}
782 
783 	/*
784 	 * For device total_bytes, we don't have reliable way to check it, as
785 	 * it can be 0 for device removal. Device size check can only be done
786 	 * by dev extents check.
787 	 */
788 	if (btrfs_device_bytes_used(leaf, ditem) >
789 	    btrfs_device_total_bytes(leaf, ditem)) {
790 		dev_item_err(leaf, slot,
791 			     "invalid bytes used: have %llu expect [0, %llu]",
792 			     btrfs_device_bytes_used(leaf, ditem),
793 			     btrfs_device_total_bytes(leaf, ditem));
794 		return -EUCLEAN;
795 	}
796 	/*
797 	 * Remaining members like io_align/type/gen/dev_group aren't really
798 	 * utilized.  Skip them to make later usage of them easier.
799 	 */
800 	return 0;
801 }
802 
803 /* Inode item error output has the same format as dir_item_err() */
804 #define inode_item_err(fs_info, eb, slot, fmt, ...)			\
805 	dir_item_err(eb, slot, fmt, __VA_ARGS__)
806 
807 static int check_inode_item(struct extent_buffer *leaf,
808 			    struct btrfs_key *key, int slot)
809 {
810 	struct btrfs_fs_info *fs_info = leaf->fs_info;
811 	struct btrfs_inode_item *iitem;
812 	u64 super_gen = btrfs_super_generation(fs_info->super_copy);
813 	u32 valid_mask = (S_IFMT | S_ISUID | S_ISGID | S_ISVTX | 0777);
814 	u32 mode;
815 
816 	if ((key->objectid < BTRFS_FIRST_FREE_OBJECTID ||
817 	     key->objectid > BTRFS_LAST_FREE_OBJECTID) &&
818 	    key->objectid != BTRFS_ROOT_TREE_DIR_OBJECTID &&
819 	    key->objectid != BTRFS_FREE_INO_OBJECTID) {
820 		generic_err(leaf, slot,
821 	"invalid key objectid: has %llu expect %llu or [%llu, %llu] or %llu",
822 			    key->objectid, BTRFS_ROOT_TREE_DIR_OBJECTID,
823 			    BTRFS_FIRST_FREE_OBJECTID,
824 			    BTRFS_LAST_FREE_OBJECTID,
825 			    BTRFS_FREE_INO_OBJECTID);
826 		return -EUCLEAN;
827 	}
828 	if (key->offset != 0) {
829 		inode_item_err(fs_info, leaf, slot,
830 			"invalid key offset: has %llu expect 0",
831 			key->offset);
832 		return -EUCLEAN;
833 	}
834 	iitem = btrfs_item_ptr(leaf, slot, struct btrfs_inode_item);
835 
836 	/* Here we use super block generation + 1 to handle log tree */
837 	if (btrfs_inode_generation(leaf, iitem) > super_gen + 1) {
838 		inode_item_err(fs_info, leaf, slot,
839 			"invalid inode generation: has %llu expect (0, %llu]",
840 			       btrfs_inode_generation(leaf, iitem),
841 			       super_gen + 1);
842 		return -EUCLEAN;
843 	}
844 	/* Note for ROOT_TREE_DIR_ITEM, mkfs could set its transid 0 */
845 	if (btrfs_inode_transid(leaf, iitem) > super_gen + 1) {
846 		inode_item_err(fs_info, leaf, slot,
847 			"invalid inode generation: has %llu expect [0, %llu]",
848 			       btrfs_inode_transid(leaf, iitem), super_gen + 1);
849 		return -EUCLEAN;
850 	}
851 
852 	/*
853 	 * For size and nbytes it's better not to be too strict, as for dir
854 	 * item its size/nbytes can easily get wrong, but doesn't affect
855 	 * anything in the fs. So here we skip the check.
856 	 */
857 	mode = btrfs_inode_mode(leaf, iitem);
858 	if (mode & ~valid_mask) {
859 		inode_item_err(fs_info, leaf, slot,
860 			       "unknown mode bit detected: 0x%x",
861 			       mode & ~valid_mask);
862 		return -EUCLEAN;
863 	}
864 
865 	/*
866 	 * S_IFMT is not bit mapped so we can't completely rely on
867 	 * is_power_of_2/has_single_bit_set, but it can save us from checking
868 	 * FIFO/CHR/DIR/REG.  Only needs to check BLK, LNK and SOCKS
869 	 */
870 	if (!has_single_bit_set(mode & S_IFMT)) {
871 		if (!S_ISLNK(mode) && !S_ISBLK(mode) && !S_ISSOCK(mode)) {
872 			inode_item_err(fs_info, leaf, slot,
873 			"invalid mode: has 0%o expect valid S_IF* bit(s)",
874 				       mode & S_IFMT);
875 			return -EUCLEAN;
876 		}
877 	}
878 	if (S_ISDIR(mode) && btrfs_inode_nlink(leaf, iitem) > 1) {
879 		inode_item_err(fs_info, leaf, slot,
880 		       "invalid nlink: has %u expect no more than 1 for dir",
881 			btrfs_inode_nlink(leaf, iitem));
882 		return -EUCLEAN;
883 	}
884 	if (btrfs_inode_flags(leaf, iitem) & ~BTRFS_INODE_FLAG_MASK) {
885 		inode_item_err(fs_info, leaf, slot,
886 			       "unknown flags detected: 0x%llx",
887 			       btrfs_inode_flags(leaf, iitem) &
888 			       ~BTRFS_INODE_FLAG_MASK);
889 		return -EUCLEAN;
890 	}
891 	return 0;
892 }
893 
894 static int check_root_item(struct extent_buffer *leaf, struct btrfs_key *key,
895 			   int slot)
896 {
897 	struct btrfs_fs_info *fs_info = leaf->fs_info;
898 	struct btrfs_root_item ri;
899 	const u64 valid_root_flags = BTRFS_ROOT_SUBVOL_RDONLY |
900 				     BTRFS_ROOT_SUBVOL_DEAD;
901 
902 	/* No such tree id */
903 	if (key->objectid == 0) {
904 		generic_err(leaf, slot, "invalid root id 0");
905 		return -EUCLEAN;
906 	}
907 
908 	/*
909 	 * Some older kernel may create ROOT_ITEM with non-zero offset, so here
910 	 * we only check offset for reloc tree whose key->offset must be a
911 	 * valid tree.
912 	 */
913 	if (key->objectid == BTRFS_TREE_RELOC_OBJECTID && key->offset == 0) {
914 		generic_err(leaf, slot, "invalid root id 0 for reloc tree");
915 		return -EUCLEAN;
916 	}
917 
918 	if (btrfs_item_size_nr(leaf, slot) != sizeof(ri)) {
919 		generic_err(leaf, slot,
920 			    "invalid root item size, have %u expect %zu",
921 			    btrfs_item_size_nr(leaf, slot), sizeof(ri));
922 	}
923 
924 	read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot),
925 			   sizeof(ri));
926 
927 	/* Generation related */
928 	if (btrfs_root_generation(&ri) >
929 	    btrfs_super_generation(fs_info->super_copy) + 1) {
930 		generic_err(leaf, slot,
931 			"invalid root generation, have %llu expect (0, %llu]",
932 			    btrfs_root_generation(&ri),
933 			    btrfs_super_generation(fs_info->super_copy) + 1);
934 		return -EUCLEAN;
935 	}
936 	if (btrfs_root_generation_v2(&ri) >
937 	    btrfs_super_generation(fs_info->super_copy) + 1) {
938 		generic_err(leaf, slot,
939 		"invalid root v2 generation, have %llu expect (0, %llu]",
940 			    btrfs_root_generation_v2(&ri),
941 			    btrfs_super_generation(fs_info->super_copy) + 1);
942 		return -EUCLEAN;
943 	}
944 	if (btrfs_root_last_snapshot(&ri) >
945 	    btrfs_super_generation(fs_info->super_copy) + 1) {
946 		generic_err(leaf, slot,
947 		"invalid root last_snapshot, have %llu expect (0, %llu]",
948 			    btrfs_root_last_snapshot(&ri),
949 			    btrfs_super_generation(fs_info->super_copy) + 1);
950 		return -EUCLEAN;
951 	}
952 
953 	/* Alignment and level check */
954 	if (!IS_ALIGNED(btrfs_root_bytenr(&ri), fs_info->sectorsize)) {
955 		generic_err(leaf, slot,
956 		"invalid root bytenr, have %llu expect to be aligned to %u",
957 			    btrfs_root_bytenr(&ri), fs_info->sectorsize);
958 		return -EUCLEAN;
959 	}
960 	if (btrfs_root_level(&ri) >= BTRFS_MAX_LEVEL) {
961 		generic_err(leaf, slot,
962 			    "invalid root level, have %u expect [0, %u]",
963 			    btrfs_root_level(&ri), BTRFS_MAX_LEVEL - 1);
964 		return -EUCLEAN;
965 	}
966 	if (ri.drop_level >= BTRFS_MAX_LEVEL) {
967 		generic_err(leaf, slot,
968 			    "invalid root level, have %u expect [0, %u]",
969 			    ri.drop_level, BTRFS_MAX_LEVEL - 1);
970 		return -EUCLEAN;
971 	}
972 
973 	/* Flags check */
974 	if (btrfs_root_flags(&ri) & ~valid_root_flags) {
975 		generic_err(leaf, slot,
976 			    "invalid root flags, have 0x%llx expect mask 0x%llx",
977 			    btrfs_root_flags(&ri), valid_root_flags);
978 		return -EUCLEAN;
979 	}
980 	return 0;
981 }
982 
983 __printf(3,4)
984 __cold
985 static void extent_err(const struct extent_buffer *eb, int slot,
986 		       const char *fmt, ...)
987 {
988 	struct btrfs_key key;
989 	struct va_format vaf;
990 	va_list args;
991 	u64 bytenr;
992 	u64 len;
993 
994 	btrfs_item_key_to_cpu(eb, &key, slot);
995 	bytenr = key.objectid;
996 	if (key.type == BTRFS_METADATA_ITEM_KEY ||
997 	    key.type == BTRFS_TREE_BLOCK_REF_KEY ||
998 	    key.type == BTRFS_SHARED_BLOCK_REF_KEY)
999 		len = eb->fs_info->nodesize;
1000 	else
1001 		len = key.offset;
1002 	va_start(args, fmt);
1003 
1004 	vaf.fmt = fmt;
1005 	vaf.va = &args;
1006 
1007 	btrfs_crit(eb->fs_info,
1008 	"corrupt %s: block=%llu slot=%d extent bytenr=%llu len=%llu %pV",
1009 		btrfs_header_level(eb) == 0 ? "leaf" : "node",
1010 		eb->start, slot, bytenr, len, &vaf);
1011 	va_end(args);
1012 }
1013 
1014 static int check_extent_item(struct extent_buffer *leaf,
1015 			     struct btrfs_key *key, int slot)
1016 {
1017 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1018 	struct btrfs_extent_item *ei;
1019 	bool is_tree_block = false;
1020 	unsigned long ptr;	/* Current pointer inside inline refs */
1021 	unsigned long end;	/* Extent item end */
1022 	const u32 item_size = btrfs_item_size_nr(leaf, slot);
1023 	u64 flags;
1024 	u64 generation;
1025 	u64 total_refs;		/* Total refs in btrfs_extent_item */
1026 	u64 inline_refs = 0;	/* found total inline refs */
1027 
1028 	if (key->type == BTRFS_METADATA_ITEM_KEY &&
1029 	    !btrfs_fs_incompat(fs_info, SKINNY_METADATA)) {
1030 		generic_err(leaf, slot,
1031 "invalid key type, METADATA_ITEM type invalid when SKINNY_METADATA feature disabled");
1032 		return -EUCLEAN;
1033 	}
1034 	/* key->objectid is the bytenr for both key types */
1035 	if (!IS_ALIGNED(key->objectid, fs_info->sectorsize)) {
1036 		generic_err(leaf, slot,
1037 		"invalid key objectid, have %llu expect to be aligned to %u",
1038 			   key->objectid, fs_info->sectorsize);
1039 		return -EUCLEAN;
1040 	}
1041 
1042 	/* key->offset is tree level for METADATA_ITEM_KEY */
1043 	if (key->type == BTRFS_METADATA_ITEM_KEY &&
1044 	    key->offset >= BTRFS_MAX_LEVEL) {
1045 		extent_err(leaf, slot,
1046 			   "invalid tree level, have %llu expect [0, %u]",
1047 			   key->offset, BTRFS_MAX_LEVEL - 1);
1048 		return -EUCLEAN;
1049 	}
1050 
1051 	/*
1052 	 * EXTENT/METADATA_ITEM consists of:
1053 	 * 1) One btrfs_extent_item
1054 	 *    Records the total refs, type and generation of the extent.
1055 	 *
1056 	 * 2) One btrfs_tree_block_info (for EXTENT_ITEM and tree backref only)
1057 	 *    Records the first key and level of the tree block.
1058 	 *
1059 	 * 2) Zero or more btrfs_extent_inline_ref(s)
1060 	 *    Each inline ref has one btrfs_extent_inline_ref shows:
1061 	 *    2.1) The ref type, one of the 4
1062 	 *         TREE_BLOCK_REF	Tree block only
1063 	 *         SHARED_BLOCK_REF	Tree block only
1064 	 *         EXTENT_DATA_REF	Data only
1065 	 *         SHARED_DATA_REF	Data only
1066 	 *    2.2) Ref type specific data
1067 	 *         Either using btrfs_extent_inline_ref::offset, or specific
1068 	 *         data structure.
1069 	 */
1070 	if (item_size < sizeof(*ei)) {
1071 		extent_err(leaf, slot,
1072 			   "invalid item size, have %u expect [%zu, %u)",
1073 			   item_size, sizeof(*ei),
1074 			   BTRFS_LEAF_DATA_SIZE(fs_info));
1075 		return -EUCLEAN;
1076 	}
1077 	end = item_size + btrfs_item_ptr_offset(leaf, slot);
1078 
1079 	/* Checks against extent_item */
1080 	ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
1081 	flags = btrfs_extent_flags(leaf, ei);
1082 	total_refs = btrfs_extent_refs(leaf, ei);
1083 	generation = btrfs_extent_generation(leaf, ei);
1084 	if (generation > btrfs_super_generation(fs_info->super_copy) + 1) {
1085 		extent_err(leaf, slot,
1086 			   "invalid generation, have %llu expect (0, %llu]",
1087 			   generation,
1088 			   btrfs_super_generation(fs_info->super_copy) + 1);
1089 		return -EUCLEAN;
1090 	}
1091 	if (!has_single_bit_set(flags & (BTRFS_EXTENT_FLAG_DATA |
1092 					 BTRFS_EXTENT_FLAG_TREE_BLOCK))) {
1093 		extent_err(leaf, slot,
1094 		"invalid extent flag, have 0x%llx expect 1 bit set in 0x%llx",
1095 			flags, BTRFS_EXTENT_FLAG_DATA |
1096 			BTRFS_EXTENT_FLAG_TREE_BLOCK);
1097 		return -EUCLEAN;
1098 	}
1099 	is_tree_block = !!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK);
1100 	if (is_tree_block) {
1101 		if (key->type == BTRFS_EXTENT_ITEM_KEY &&
1102 		    key->offset != fs_info->nodesize) {
1103 			extent_err(leaf, slot,
1104 				   "invalid extent length, have %llu expect %u",
1105 				   key->offset, fs_info->nodesize);
1106 			return -EUCLEAN;
1107 		}
1108 	} else {
1109 		if (key->type != BTRFS_EXTENT_ITEM_KEY) {
1110 			extent_err(leaf, slot,
1111 			"invalid key type, have %u expect %u for data backref",
1112 				   key->type, BTRFS_EXTENT_ITEM_KEY);
1113 			return -EUCLEAN;
1114 		}
1115 		if (!IS_ALIGNED(key->offset, fs_info->sectorsize)) {
1116 			extent_err(leaf, slot,
1117 			"invalid extent length, have %llu expect aligned to %u",
1118 				   key->offset, fs_info->sectorsize);
1119 			return -EUCLEAN;
1120 		}
1121 	}
1122 	ptr = (unsigned long)(struct btrfs_extent_item *)(ei + 1);
1123 
1124 	/* Check the special case of btrfs_tree_block_info */
1125 	if (is_tree_block && key->type != BTRFS_METADATA_ITEM_KEY) {
1126 		struct btrfs_tree_block_info *info;
1127 
1128 		info = (struct btrfs_tree_block_info *)ptr;
1129 		if (btrfs_tree_block_level(leaf, info) >= BTRFS_MAX_LEVEL) {
1130 			extent_err(leaf, slot,
1131 			"invalid tree block info level, have %u expect [0, %u]",
1132 				   btrfs_tree_block_level(leaf, info),
1133 				   BTRFS_MAX_LEVEL - 1);
1134 			return -EUCLEAN;
1135 		}
1136 		ptr = (unsigned long)(struct btrfs_tree_block_info *)(info + 1);
1137 	}
1138 
1139 	/* Check inline refs */
1140 	while (ptr < end) {
1141 		struct btrfs_extent_inline_ref *iref;
1142 		struct btrfs_extent_data_ref *dref;
1143 		struct btrfs_shared_data_ref *sref;
1144 		u64 dref_offset;
1145 		u64 inline_offset;
1146 		u8 inline_type;
1147 
1148 		if (ptr + sizeof(*iref) > end) {
1149 			extent_err(leaf, slot,
1150 "inline ref item overflows extent item, ptr %lu iref size %zu end %lu",
1151 				   ptr, sizeof(*iref), end);
1152 			return -EUCLEAN;
1153 		}
1154 		iref = (struct btrfs_extent_inline_ref *)ptr;
1155 		inline_type = btrfs_extent_inline_ref_type(leaf, iref);
1156 		inline_offset = btrfs_extent_inline_ref_offset(leaf, iref);
1157 		if (ptr + btrfs_extent_inline_ref_size(inline_type) > end) {
1158 			extent_err(leaf, slot,
1159 "inline ref item overflows extent item, ptr %lu iref size %u end %lu",
1160 				   ptr, inline_type, end);
1161 			return -EUCLEAN;
1162 		}
1163 
1164 		switch (inline_type) {
1165 		/* inline_offset is subvolid of the owner, no need to check */
1166 		case BTRFS_TREE_BLOCK_REF_KEY:
1167 			inline_refs++;
1168 			break;
1169 		/* Contains parent bytenr */
1170 		case BTRFS_SHARED_BLOCK_REF_KEY:
1171 			if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
1172 				extent_err(leaf, slot,
1173 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1174 					   inline_offset, fs_info->sectorsize);
1175 				return -EUCLEAN;
1176 			}
1177 			inline_refs++;
1178 			break;
1179 		/*
1180 		 * Contains owner subvolid, owner key objectid, adjusted offset.
1181 		 * The only obvious corruption can happen in that offset.
1182 		 */
1183 		case BTRFS_EXTENT_DATA_REF_KEY:
1184 			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
1185 			dref_offset = btrfs_extent_data_ref_offset(leaf, dref);
1186 			if (!IS_ALIGNED(dref_offset, fs_info->sectorsize)) {
1187 				extent_err(leaf, slot,
1188 		"invalid data ref offset, have %llu expect aligned to %u",
1189 					   dref_offset, fs_info->sectorsize);
1190 				return -EUCLEAN;
1191 			}
1192 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
1193 			break;
1194 		/* Contains parent bytenr and ref count */
1195 		case BTRFS_SHARED_DATA_REF_KEY:
1196 			sref = (struct btrfs_shared_data_ref *)(iref + 1);
1197 			if (!IS_ALIGNED(inline_offset, fs_info->sectorsize)) {
1198 				extent_err(leaf, slot,
1199 		"invalid data parent bytenr, have %llu expect aligned to %u",
1200 					   inline_offset, fs_info->sectorsize);
1201 				return -EUCLEAN;
1202 			}
1203 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
1204 			break;
1205 		default:
1206 			extent_err(leaf, slot, "unknown inline ref type: %u",
1207 				   inline_type);
1208 			return -EUCLEAN;
1209 		}
1210 		ptr += btrfs_extent_inline_ref_size(inline_type);
1211 	}
1212 	/* No padding is allowed */
1213 	if (ptr != end) {
1214 		extent_err(leaf, slot,
1215 			   "invalid extent item size, padding bytes found");
1216 		return -EUCLEAN;
1217 	}
1218 
1219 	/* Finally, check the inline refs against total refs */
1220 	if (inline_refs > total_refs) {
1221 		extent_err(leaf, slot,
1222 			"invalid extent refs, have %llu expect >= inline %llu",
1223 			   total_refs, inline_refs);
1224 		return -EUCLEAN;
1225 	}
1226 	return 0;
1227 }
1228 
1229 static int check_simple_keyed_refs(struct extent_buffer *leaf,
1230 				   struct btrfs_key *key, int slot)
1231 {
1232 	u32 expect_item_size = 0;
1233 
1234 	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
1235 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
1236 
1237 	if (btrfs_item_size_nr(leaf, slot) != expect_item_size) {
1238 		generic_err(leaf, slot,
1239 		"invalid item size, have %u expect %u for key type %u",
1240 			    btrfs_item_size_nr(leaf, slot),
1241 			    expect_item_size, key->type);
1242 		return -EUCLEAN;
1243 	}
1244 	if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
1245 		generic_err(leaf, slot,
1246 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1247 			    key->objectid, leaf->fs_info->sectorsize);
1248 		return -EUCLEAN;
1249 	}
1250 	if (key->type != BTRFS_TREE_BLOCK_REF_KEY &&
1251 	    !IS_ALIGNED(key->offset, leaf->fs_info->sectorsize)) {
1252 		extent_err(leaf, slot,
1253 		"invalid tree parent bytenr, have %llu expect aligned to %u",
1254 			   key->offset, leaf->fs_info->sectorsize);
1255 		return -EUCLEAN;
1256 	}
1257 	return 0;
1258 }
1259 
1260 static int check_extent_data_ref(struct extent_buffer *leaf,
1261 				 struct btrfs_key *key, int slot)
1262 {
1263 	struct btrfs_extent_data_ref *dref;
1264 	unsigned long ptr = btrfs_item_ptr_offset(leaf, slot);
1265 	const unsigned long end = ptr + btrfs_item_size_nr(leaf, slot);
1266 
1267 	if (btrfs_item_size_nr(leaf, slot) % sizeof(*dref) != 0) {
1268 		generic_err(leaf, slot,
1269 	"invalid item size, have %u expect aligned to %zu for key type %u",
1270 			    btrfs_item_size_nr(leaf, slot),
1271 			    sizeof(*dref), key->type);
1272 	}
1273 	if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) {
1274 		generic_err(leaf, slot,
1275 "invalid key objectid for shared block ref, have %llu expect aligned to %u",
1276 			    key->objectid, leaf->fs_info->sectorsize);
1277 		return -EUCLEAN;
1278 	}
1279 	for (; ptr < end; ptr += sizeof(*dref)) {
1280 		u64 root_objectid;
1281 		u64 owner;
1282 		u64 offset;
1283 		u64 hash;
1284 
1285 		dref = (struct btrfs_extent_data_ref *)ptr;
1286 		root_objectid = btrfs_extent_data_ref_root(leaf, dref);
1287 		owner = btrfs_extent_data_ref_objectid(leaf, dref);
1288 		offset = btrfs_extent_data_ref_offset(leaf, dref);
1289 		hash = hash_extent_data_ref(root_objectid, owner, offset);
1290 		if (hash != key->offset) {
1291 			extent_err(leaf, slot,
1292 	"invalid extent data ref hash, item has 0x%016llx key has 0x%016llx",
1293 				   hash, key->offset);
1294 			return -EUCLEAN;
1295 		}
1296 		if (!IS_ALIGNED(offset, leaf->fs_info->sectorsize)) {
1297 			extent_err(leaf, slot,
1298 	"invalid extent data backref offset, have %llu expect aligned to %u",
1299 				   offset, leaf->fs_info->sectorsize);
1300 		}
1301 	}
1302 	return 0;
1303 }
1304 
1305 #define inode_ref_err(fs_info, eb, slot, fmt, args...)			\
1306 	inode_item_err(fs_info, eb, slot, fmt, ##args)
1307 static int check_inode_ref(struct extent_buffer *leaf,
1308 			   struct btrfs_key *key, struct btrfs_key *prev_key,
1309 			   int slot)
1310 {
1311 	struct btrfs_inode_ref *iref;
1312 	unsigned long ptr;
1313 	unsigned long end;
1314 
1315 	if (!check_prev_ino(leaf, key, slot, prev_key))
1316 		return -EUCLEAN;
1317 	/* namelen can't be 0, so item_size == sizeof() is also invalid */
1318 	if (btrfs_item_size_nr(leaf, slot) <= sizeof(*iref)) {
1319 		inode_ref_err(fs_info, leaf, slot,
1320 			"invalid item size, have %u expect (%zu, %u)",
1321 			btrfs_item_size_nr(leaf, slot),
1322 			sizeof(*iref), BTRFS_LEAF_DATA_SIZE(leaf->fs_info));
1323 		return -EUCLEAN;
1324 	}
1325 
1326 	ptr = btrfs_item_ptr_offset(leaf, slot);
1327 	end = ptr + btrfs_item_size_nr(leaf, slot);
1328 	while (ptr < end) {
1329 		u16 namelen;
1330 
1331 		if (ptr + sizeof(iref) > end) {
1332 			inode_ref_err(fs_info, leaf, slot,
1333 			"inode ref overflow, ptr %lu end %lu inode_ref_size %zu",
1334 				ptr, end, sizeof(iref));
1335 			return -EUCLEAN;
1336 		}
1337 
1338 		iref = (struct btrfs_inode_ref *)ptr;
1339 		namelen = btrfs_inode_ref_name_len(leaf, iref);
1340 		if (ptr + sizeof(*iref) + namelen > end) {
1341 			inode_ref_err(fs_info, leaf, slot,
1342 				"inode ref overflow, ptr %lu end %lu namelen %u",
1343 				ptr, end, namelen);
1344 			return -EUCLEAN;
1345 		}
1346 
1347 		/*
1348 		 * NOTE: In theory we should record all found index numbers
1349 		 * to find any duplicated indexes, but that will be too time
1350 		 * consuming for inodes with too many hard links.
1351 		 */
1352 		ptr += sizeof(*iref) + namelen;
1353 	}
1354 	return 0;
1355 }
1356 
1357 /*
1358  * Common point to switch the item-specific validation.
1359  */
1360 static int check_leaf_item(struct extent_buffer *leaf,
1361 			   struct btrfs_key *key, int slot,
1362 			   struct btrfs_key *prev_key)
1363 {
1364 	int ret = 0;
1365 	struct btrfs_chunk *chunk;
1366 
1367 	switch (key->type) {
1368 	case BTRFS_EXTENT_DATA_KEY:
1369 		ret = check_extent_data_item(leaf, key, slot, prev_key);
1370 		break;
1371 	case BTRFS_EXTENT_CSUM_KEY:
1372 		ret = check_csum_item(leaf, key, slot, prev_key);
1373 		break;
1374 	case BTRFS_DIR_ITEM_KEY:
1375 	case BTRFS_DIR_INDEX_KEY:
1376 	case BTRFS_XATTR_ITEM_KEY:
1377 		ret = check_dir_item(leaf, key, prev_key, slot);
1378 		break;
1379 	case BTRFS_INODE_REF_KEY:
1380 		ret = check_inode_ref(leaf, key, prev_key, slot);
1381 		break;
1382 	case BTRFS_BLOCK_GROUP_ITEM_KEY:
1383 		ret = check_block_group_item(leaf, key, slot);
1384 		break;
1385 	case BTRFS_CHUNK_ITEM_KEY:
1386 		chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1387 		ret = btrfs_check_chunk_valid(leaf, chunk, key->offset);
1388 		break;
1389 	case BTRFS_DEV_ITEM_KEY:
1390 		ret = check_dev_item(leaf, key, slot);
1391 		break;
1392 	case BTRFS_INODE_ITEM_KEY:
1393 		ret = check_inode_item(leaf, key, slot);
1394 		break;
1395 	case BTRFS_ROOT_ITEM_KEY:
1396 		ret = check_root_item(leaf, key, slot);
1397 		break;
1398 	case BTRFS_EXTENT_ITEM_KEY:
1399 	case BTRFS_METADATA_ITEM_KEY:
1400 		ret = check_extent_item(leaf, key, slot);
1401 		break;
1402 	case BTRFS_TREE_BLOCK_REF_KEY:
1403 	case BTRFS_SHARED_DATA_REF_KEY:
1404 	case BTRFS_SHARED_BLOCK_REF_KEY:
1405 		ret = check_simple_keyed_refs(leaf, key, slot);
1406 		break;
1407 	case BTRFS_EXTENT_DATA_REF_KEY:
1408 		ret = check_extent_data_ref(leaf, key, slot);
1409 		break;
1410 	}
1411 	return ret;
1412 }
1413 
1414 static int check_leaf(struct extent_buffer *leaf, bool check_item_data)
1415 {
1416 	struct btrfs_fs_info *fs_info = leaf->fs_info;
1417 	/* No valid key type is 0, so all key should be larger than this key */
1418 	struct btrfs_key prev_key = {0, 0, 0};
1419 	struct btrfs_key key;
1420 	u32 nritems = btrfs_header_nritems(leaf);
1421 	int slot;
1422 
1423 	if (btrfs_header_level(leaf) != 0) {
1424 		generic_err(leaf, 0,
1425 			"invalid level for leaf, have %d expect 0",
1426 			btrfs_header_level(leaf));
1427 		return -EUCLEAN;
1428 	}
1429 
1430 	/*
1431 	 * Extent buffers from a relocation tree have a owner field that
1432 	 * corresponds to the subvolume tree they are based on. So just from an
1433 	 * extent buffer alone we can not find out what is the id of the
1434 	 * corresponding subvolume tree, so we can not figure out if the extent
1435 	 * buffer corresponds to the root of the relocation tree or not. So
1436 	 * skip this check for relocation trees.
1437 	 */
1438 	if (nritems == 0 && !btrfs_header_flag(leaf, BTRFS_HEADER_FLAG_RELOC)) {
1439 		u64 owner = btrfs_header_owner(leaf);
1440 
1441 		/* These trees must never be empty */
1442 		if (owner == BTRFS_ROOT_TREE_OBJECTID ||
1443 		    owner == BTRFS_CHUNK_TREE_OBJECTID ||
1444 		    owner == BTRFS_EXTENT_TREE_OBJECTID ||
1445 		    owner == BTRFS_DEV_TREE_OBJECTID ||
1446 		    owner == BTRFS_FS_TREE_OBJECTID ||
1447 		    owner == BTRFS_DATA_RELOC_TREE_OBJECTID) {
1448 			generic_err(leaf, 0,
1449 			"invalid root, root %llu must never be empty",
1450 				    owner);
1451 			return -EUCLEAN;
1452 		}
1453 		/* Unknown tree */
1454 		if (owner == 0) {
1455 			generic_err(leaf, 0,
1456 				"invalid owner, root 0 is not defined");
1457 			return -EUCLEAN;
1458 		}
1459 		return 0;
1460 	}
1461 
1462 	if (nritems == 0)
1463 		return 0;
1464 
1465 	/*
1466 	 * Check the following things to make sure this is a good leaf, and
1467 	 * leaf users won't need to bother with similar sanity checks:
1468 	 *
1469 	 * 1) key ordering
1470 	 * 2) item offset and size
1471 	 *    No overlap, no hole, all inside the leaf.
1472 	 * 3) item content
1473 	 *    If possible, do comprehensive sanity check.
1474 	 *    NOTE: All checks must only rely on the item data itself.
1475 	 */
1476 	for (slot = 0; slot < nritems; slot++) {
1477 		u32 item_end_expected;
1478 		int ret;
1479 
1480 		btrfs_item_key_to_cpu(leaf, &key, slot);
1481 
1482 		/* Make sure the keys are in the right order */
1483 		if (btrfs_comp_cpu_keys(&prev_key, &key) >= 0) {
1484 			generic_err(leaf, slot,
1485 	"bad key order, prev (%llu %u %llu) current (%llu %u %llu)",
1486 				prev_key.objectid, prev_key.type,
1487 				prev_key.offset, key.objectid, key.type,
1488 				key.offset);
1489 			return -EUCLEAN;
1490 		}
1491 
1492 		/*
1493 		 * Make sure the offset and ends are right, remember that the
1494 		 * item data starts at the end of the leaf and grows towards the
1495 		 * front.
1496 		 */
1497 		if (slot == 0)
1498 			item_end_expected = BTRFS_LEAF_DATA_SIZE(fs_info);
1499 		else
1500 			item_end_expected = btrfs_item_offset_nr(leaf,
1501 								 slot - 1);
1502 		if (btrfs_item_end_nr(leaf, slot) != item_end_expected) {
1503 			generic_err(leaf, slot,
1504 				"unexpected item end, have %u expect %u",
1505 				btrfs_item_end_nr(leaf, slot),
1506 				item_end_expected);
1507 			return -EUCLEAN;
1508 		}
1509 
1510 		/*
1511 		 * Check to make sure that we don't point outside of the leaf,
1512 		 * just in case all the items are consistent to each other, but
1513 		 * all point outside of the leaf.
1514 		 */
1515 		if (btrfs_item_end_nr(leaf, slot) >
1516 		    BTRFS_LEAF_DATA_SIZE(fs_info)) {
1517 			generic_err(leaf, slot,
1518 			"slot end outside of leaf, have %u expect range [0, %u]",
1519 				btrfs_item_end_nr(leaf, slot),
1520 				BTRFS_LEAF_DATA_SIZE(fs_info));
1521 			return -EUCLEAN;
1522 		}
1523 
1524 		/* Also check if the item pointer overlaps with btrfs item. */
1525 		if (btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item) >
1526 		    btrfs_item_ptr_offset(leaf, slot)) {
1527 			generic_err(leaf, slot,
1528 		"slot overlaps with its data, item end %lu data start %lu",
1529 				btrfs_item_nr_offset(slot) +
1530 				sizeof(struct btrfs_item),
1531 				btrfs_item_ptr_offset(leaf, slot));
1532 			return -EUCLEAN;
1533 		}
1534 
1535 		if (check_item_data) {
1536 			/*
1537 			 * Check if the item size and content meet other
1538 			 * criteria
1539 			 */
1540 			ret = check_leaf_item(leaf, &key, slot, &prev_key);
1541 			if (ret < 0)
1542 				return ret;
1543 		}
1544 
1545 		prev_key.objectid = key.objectid;
1546 		prev_key.type = key.type;
1547 		prev_key.offset = key.offset;
1548 	}
1549 
1550 	return 0;
1551 }
1552 
1553 int btrfs_check_leaf_full(struct extent_buffer *leaf)
1554 {
1555 	return check_leaf(leaf, true);
1556 }
1557 ALLOW_ERROR_INJECTION(btrfs_check_leaf_full, ERRNO);
1558 
1559 int btrfs_check_leaf_relaxed(struct extent_buffer *leaf)
1560 {
1561 	return check_leaf(leaf, false);
1562 }
1563 
1564 int btrfs_check_node(struct extent_buffer *node)
1565 {
1566 	struct btrfs_fs_info *fs_info = node->fs_info;
1567 	unsigned long nr = btrfs_header_nritems(node);
1568 	struct btrfs_key key, next_key;
1569 	int slot;
1570 	int level = btrfs_header_level(node);
1571 	u64 bytenr;
1572 	int ret = 0;
1573 
1574 	if (level <= 0 || level >= BTRFS_MAX_LEVEL) {
1575 		generic_err(node, 0,
1576 			"invalid level for node, have %d expect [1, %d]",
1577 			level, BTRFS_MAX_LEVEL - 1);
1578 		return -EUCLEAN;
1579 	}
1580 	if (nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(fs_info)) {
1581 		btrfs_crit(fs_info,
1582 "corrupt node: root=%llu block=%llu, nritems too %s, have %lu expect range [1,%u]",
1583 			   btrfs_header_owner(node), node->start,
1584 			   nr == 0 ? "small" : "large", nr,
1585 			   BTRFS_NODEPTRS_PER_BLOCK(fs_info));
1586 		return -EUCLEAN;
1587 	}
1588 
1589 	for (slot = 0; slot < nr - 1; slot++) {
1590 		bytenr = btrfs_node_blockptr(node, slot);
1591 		btrfs_node_key_to_cpu(node, &key, slot);
1592 		btrfs_node_key_to_cpu(node, &next_key, slot + 1);
1593 
1594 		if (!bytenr) {
1595 			generic_err(node, slot,
1596 				"invalid NULL node pointer");
1597 			ret = -EUCLEAN;
1598 			goto out;
1599 		}
1600 		if (!IS_ALIGNED(bytenr, fs_info->sectorsize)) {
1601 			generic_err(node, slot,
1602 			"unaligned pointer, have %llu should be aligned to %u",
1603 				bytenr, fs_info->sectorsize);
1604 			ret = -EUCLEAN;
1605 			goto out;
1606 		}
1607 
1608 		if (btrfs_comp_cpu_keys(&key, &next_key) >= 0) {
1609 			generic_err(node, slot,
1610 	"bad key order, current (%llu %u %llu) next (%llu %u %llu)",
1611 				key.objectid, key.type, key.offset,
1612 				next_key.objectid, next_key.type,
1613 				next_key.offset);
1614 			ret = -EUCLEAN;
1615 			goto out;
1616 		}
1617 	}
1618 out:
1619 	return ret;
1620 }
1621 ALLOW_ERROR_INJECTION(btrfs_check_node, ERRNO);
1622