1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2017-2023 Oracle. All Rights Reserved.
4 * Author: Darrick J. Wong <djwong@kernel.org>
5 */
6 #include "xfs_platform.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_log_format.h"
13 #include "xfs_trans.h"
14 #include "xfs_inode.h"
15 #include "xfs_da_format.h"
16 #include "xfs_da_btree.h"
17 #include "xfs_attr.h"
18 #include "xfs_attr_leaf.h"
19 #include "xfs_attr_sf.h"
20 #include "xfs_parent.h"
21 #include "scrub/scrub.h"
22 #include "scrub/common.h"
23 #include "scrub/dabtree.h"
24 #include "scrub/attr.h"
25 #include "scrub/listxattr.h"
26 #include "scrub/repair.h"
27
28 /* Free the buffers linked from the xattr buffer. */
29 static void
xchk_xattr_buf_cleanup(void * priv)30 xchk_xattr_buf_cleanup(
31 void *priv)
32 {
33 struct xchk_xattr_buf *ab = priv;
34
35 kvfree(ab->freemap);
36 ab->freemap = NULL;
37 kvfree(ab->usedmap);
38 ab->usedmap = NULL;
39 kvfree(ab->value);
40 ab->value = NULL;
41 ab->value_sz = 0;
42 kvfree(ab->name);
43 ab->name = NULL;
44 }
45
46 /*
47 * Allocate the free space bitmap if we're trying harder; there are leaf blocks
48 * in the attr fork; or we can't tell if there are leaf blocks.
49 */
50 static inline bool
xchk_xattr_want_freemap(struct xfs_scrub * sc)51 xchk_xattr_want_freemap(
52 struct xfs_scrub *sc)
53 {
54 struct xfs_ifork *ifp;
55
56 if (sc->flags & XCHK_TRY_HARDER)
57 return true;
58
59 if (!sc->ip)
60 return true;
61
62 ifp = xfs_ifork_ptr(sc->ip, XFS_ATTR_FORK);
63 if (!ifp)
64 return false;
65
66 return xfs_ifork_has_extents(ifp);
67 }
68
69 /*
70 * Allocate enough memory to hold an attr value and attr block bitmaps,
71 * reallocating the buffer if necessary. Buffer contents are not preserved
72 * across a reallocation.
73 */
74 int
xchk_setup_xattr_buf(struct xfs_scrub * sc,size_t value_size)75 xchk_setup_xattr_buf(
76 struct xfs_scrub *sc,
77 size_t value_size)
78 {
79 size_t bmp_sz;
80 struct xchk_xattr_buf *ab = sc->buf;
81 void *new_val;
82
83 bmp_sz = sizeof(long) * BITS_TO_LONGS(sc->mp->m_attr_geo->blksize);
84
85 if (ab)
86 goto resize_value;
87
88 ab = kvzalloc_obj(struct xchk_xattr_buf, XCHK_GFP_FLAGS);
89 if (!ab)
90 return -ENOMEM;
91 sc->buf = ab;
92 sc->buf_cleanup = xchk_xattr_buf_cleanup;
93
94 ab->usedmap = kvmalloc(bmp_sz, XCHK_GFP_FLAGS);
95 if (!ab->usedmap)
96 return -ENOMEM;
97
98 if (xchk_xattr_want_freemap(sc)) {
99 ab->freemap = kvmalloc(bmp_sz, XCHK_GFP_FLAGS);
100 if (!ab->freemap)
101 return -ENOMEM;
102 }
103
104 if (xchk_could_repair(sc)) {
105 ab->name = kvmalloc(XATTR_NAME_MAX + 1, XCHK_GFP_FLAGS);
106 if (!ab->name)
107 return -ENOMEM;
108 }
109
110 resize_value:
111 if (ab->value_sz >= value_size)
112 return 0;
113
114 if (ab->value) {
115 kvfree(ab->value);
116 ab->value = NULL;
117 ab->value_sz = 0;
118 }
119
120 new_val = kvmalloc(value_size, XCHK_GFP_FLAGS);
121 if (!new_val)
122 return -ENOMEM;
123
124 ab->value = new_val;
125 ab->value_sz = value_size;
126 return 0;
127 }
128
129 /* Set us up to scrub an inode's extended attributes. */
130 int
xchk_setup_xattr(struct xfs_scrub * sc)131 xchk_setup_xattr(
132 struct xfs_scrub *sc)
133 {
134 int error;
135
136 if (xchk_could_repair(sc)) {
137 error = xrep_setup_xattr(sc);
138 if (error)
139 return error;
140 }
141
142 /*
143 * We failed to get memory while checking attrs, so this time try to
144 * get all the memory we're ever going to need. Allocate the buffer
145 * without the inode lock held, which means we can sleep.
146 */
147 if (sc->flags & XCHK_TRY_HARDER) {
148 error = xchk_setup_xattr_buf(sc, XATTR_SIZE_MAX);
149 if (error)
150 return error;
151 }
152
153 return xchk_setup_inode_contents(sc, 0);
154 }
155
156 /* Extended Attributes */
157
158 /*
159 * Check that an extended attribute key can be looked up by hash.
160 *
161 * We use the extended attribute walk helper to call this function for every
162 * attribute key in an inode. Once we're here, we load the attribute value to
163 * see if any errors happen, or if we get more or less data than we expected.
164 */
165 static int
xchk_xattr_actor(struct xfs_scrub * sc,struct xfs_inode * ip,unsigned int attr_flags,const unsigned char * name,unsigned int namelen,const void * value,unsigned int valuelen,void * priv)166 xchk_xattr_actor(
167 struct xfs_scrub *sc,
168 struct xfs_inode *ip,
169 unsigned int attr_flags,
170 const unsigned char *name,
171 unsigned int namelen,
172 const void *value,
173 unsigned int valuelen,
174 void *priv)
175 {
176 struct xfs_da_args args = {
177 .attr_filter = attr_flags & XFS_ATTR_NSP_ONDISK_MASK,
178 .geo = sc->mp->m_attr_geo,
179 .whichfork = XFS_ATTR_FORK,
180 .dp = ip,
181 .name = name,
182 .namelen = namelen,
183 .trans = sc->tp,
184 .valuelen = valuelen,
185 .owner = ip->i_ino,
186 };
187 struct xchk_xattr_buf *ab;
188 int error = 0;
189
190 ab = sc->buf;
191
192 if (xchk_should_terminate(sc, &error))
193 return error;
194
195 if (attr_flags & ~XFS_ATTR_ONDISK_MASK) {
196 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, args.blkno);
197 return -ECANCELED;
198 }
199
200 if (attr_flags & XFS_ATTR_INCOMPLETE) {
201 /* Incomplete attr key, just mark the inode for preening. */
202 xchk_ino_set_preen(sc, ip->i_ino);
203 return 0;
204 }
205
206 /* Does this name make sense? */
207 if (!xfs_attr_namecheck(attr_flags, name, namelen)) {
208 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, args.blkno);
209 return -ECANCELED;
210 }
211
212 /* Check parent pointer record. */
213 if ((attr_flags & XFS_ATTR_PARENT) &&
214 !xfs_parent_valuecheck(sc->mp, value, valuelen)) {
215 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, args.blkno);
216 return -ECANCELED;
217 }
218
219 /*
220 * Try to allocate enough memory to extract the attr value. If that
221 * doesn't work, return -EDEADLOCK as a signal to try again with a
222 * maximally sized buffer.
223 */
224 error = xchk_setup_xattr_buf(sc, valuelen);
225 if (error == -ENOMEM)
226 error = -EDEADLOCK;
227 if (error)
228 return error;
229
230 /*
231 * Parent pointers are matched on attr name and value, so we must
232 * supply the xfs_parent_rec here when confirming that the dabtree
233 * indexing works correctly.
234 */
235 if (attr_flags & XFS_ATTR_PARENT)
236 memcpy(ab->value, value, valuelen);
237
238 args.value = ab->value;
239
240 /*
241 * Get the attr value to ensure that lookup can find this attribute
242 * through the dabtree indexing and that remote value retrieval also
243 * works correctly.
244 */
245 xfs_attr_sethash(&args);
246 error = xfs_attr_get_ilocked(&args);
247 /* ENODATA means the hash lookup failed and the attr is bad */
248 if (error == -ENODATA)
249 error = -EFSCORRUPTED;
250 if (!xchk_fblock_process_error(sc, XFS_ATTR_FORK, args.blkno,
251 &error))
252 return error;
253 if (args.valuelen != valuelen)
254 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, args.blkno);
255
256 return 0;
257 }
258
259 /*
260 * Mark a range [start, start+len) in this map. Returns true if the
261 * region was free, and false if there's a conflict or a problem.
262 *
263 * Within a char, the lowest bit of the char represents the byte with
264 * the smallest address
265 */
266 bool
xchk_xattr_set_map(struct xfs_scrub * sc,unsigned long * map,unsigned int start,unsigned int len)267 xchk_xattr_set_map(
268 struct xfs_scrub *sc,
269 unsigned long *map,
270 unsigned int start,
271 unsigned int len)
272 {
273 unsigned int mapsize = sc->mp->m_attr_geo->blksize;
274 bool ret = true;
275
276 if (start >= mapsize)
277 return false;
278 if (start + len > mapsize) {
279 len = mapsize - start;
280 ret = false;
281 }
282
283 if (find_next_bit(map, mapsize, start) < start + len)
284 ret = false;
285 bitmap_set(map, start, len);
286
287 return ret;
288 }
289
290 /*
291 * Check this leaf entry's relations to everything else.
292 * Returns the number of bytes used for the name/value data.
293 */
294 STATIC void
xchk_xattr_entry(struct xchk_da_btree * ds,int level,char * buf_end,struct xfs_attr_leafblock * leaf,struct xfs_attr3_icleaf_hdr * leafhdr,struct xfs_attr_leaf_entry * ent,int idx,unsigned int * usedbytes,__u32 * last_hashval)295 xchk_xattr_entry(
296 struct xchk_da_btree *ds,
297 int level,
298 char *buf_end,
299 struct xfs_attr_leafblock *leaf,
300 struct xfs_attr3_icleaf_hdr *leafhdr,
301 struct xfs_attr_leaf_entry *ent,
302 int idx,
303 unsigned int *usedbytes,
304 __u32 *last_hashval)
305 {
306 struct xfs_mount *mp = ds->state->mp;
307 struct xchk_xattr_buf *ab = ds->sc->buf;
308 char *name_end;
309 struct xfs_attr_leaf_name_local *lentry;
310 struct xfs_attr_leaf_name_remote *rentry;
311 unsigned int nameidx;
312 unsigned int namesize;
313
314 if (ent->pad2 != 0)
315 xchk_da_set_corrupt(ds, level);
316
317 /* Hash values in order? */
318 if (be32_to_cpu(ent->hashval) < *last_hashval)
319 xchk_da_set_corrupt(ds, level);
320 *last_hashval = be32_to_cpu(ent->hashval);
321
322 nameidx = be16_to_cpu(ent->nameidx);
323 if (nameidx < leafhdr->firstused ||
324 nameidx >= mp->m_attr_geo->blksize) {
325 xchk_da_set_corrupt(ds, level);
326 return;
327 }
328
329 /* Check the name information. */
330 if (ent->flags & XFS_ATTR_LOCAL) {
331 lentry = xfs_attr3_leaf_name_local(leaf, idx);
332 namesize = xfs_attr_leaf_entsize_local(lentry->namelen,
333 be16_to_cpu(lentry->valuelen));
334 name_end = (char *)lentry + namesize;
335 if (lentry->namelen == 0)
336 xchk_da_set_corrupt(ds, level);
337 } else {
338 rentry = xfs_attr3_leaf_name_remote(leaf, idx);
339 namesize = xfs_attr_leaf_entsize_remote(rentry->namelen);
340 name_end = (char *)rentry + namesize;
341 if (rentry->namelen == 0)
342 xchk_da_set_corrupt(ds, level);
343 if (rentry->valueblk == 0 &&
344 !(ent->flags & XFS_ATTR_INCOMPLETE))
345 xchk_da_set_corrupt(ds, level);
346 }
347 if (name_end > buf_end)
348 xchk_da_set_corrupt(ds, level);
349
350 if (!xchk_xattr_set_map(ds->sc, ab->usedmap, nameidx, namesize))
351 xchk_da_set_corrupt(ds, level);
352 if (!(ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
353 *usedbytes += namesize;
354 }
355
356 /* Scrub an attribute leaf. */
357 STATIC int
xchk_xattr_block(struct xchk_da_btree * ds,int level)358 xchk_xattr_block(
359 struct xchk_da_btree *ds,
360 int level)
361 {
362 struct xfs_attr3_icleaf_hdr leafhdr;
363 struct xfs_mount *mp = ds->state->mp;
364 struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
365 struct xfs_buf *bp = blk->bp;
366 xfs_dablk_t *last_checked = ds->private;
367 struct xfs_attr_leafblock *leaf = bp->b_addr;
368 struct xfs_attr_leaf_entry *ent;
369 struct xfs_attr_leaf_entry *entries;
370 struct xchk_xattr_buf *ab = ds->sc->buf;
371 char *buf_end;
372 size_t off;
373 __u32 last_hashval = 0;
374 unsigned int usedbytes = 0;
375 unsigned int hdrsize;
376 int i;
377
378 if (*last_checked == blk->blkno)
379 return 0;
380
381 *last_checked = blk->blkno;
382 bitmap_zero(ab->usedmap, mp->m_attr_geo->blksize);
383 bitmap_zero(ab->freemap, mp->m_attr_geo->blksize);
384
385 /* Check all the padding. */
386 if (xfs_has_crc(ds->sc->mp)) {
387 struct xfs_attr3_leafblock *leaf3 = bp->b_addr;
388
389 if (leaf3->hdr.pad1 != 0 || leaf3->hdr.pad2 != 0 ||
390 leaf3->hdr.info.hdr.pad != 0)
391 xchk_da_set_corrupt(ds, level);
392 } else {
393 if (leaf->hdr.pad1 != 0 || leaf->hdr.info.pad != 0)
394 xchk_da_set_corrupt(ds, level);
395 }
396
397 /* Check the leaf header */
398 xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
399 hdrsize = xfs_attr3_leaf_hdr_size(leaf);
400
401 /*
402 * Empty xattr leaf blocks mapped at block 0 are probably a byproduct
403 * of a race between setxattr and a log shutdown. Anywhere else in the
404 * attr fork is a corruption.
405 */
406 if (leafhdr.count == 0) {
407 if (blk->blkno == 0)
408 xchk_da_set_preen(ds, level);
409 else
410 xchk_da_set_corrupt(ds, level);
411 }
412 if (leafhdr.usedbytes > mp->m_attr_geo->blksize)
413 xchk_da_set_corrupt(ds, level);
414 if (leafhdr.firstused > mp->m_attr_geo->blksize)
415 xchk_da_set_corrupt(ds, level);
416 if (leafhdr.firstused < hdrsize)
417 xchk_da_set_corrupt(ds, level);
418 if (!xchk_xattr_set_map(ds->sc, ab->usedmap, 0, hdrsize))
419 xchk_da_set_corrupt(ds, level);
420 if (leafhdr.holes)
421 xchk_da_set_preen(ds, level);
422
423 if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
424 goto out;
425
426 entries = xfs_attr3_leaf_entryp(leaf);
427 if ((char *)&entries[leafhdr.count] > (char *)leaf + leafhdr.firstused)
428 xchk_da_set_corrupt(ds, level);
429
430 if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
431 goto out;
432
433 buf_end = (char *)bp->b_addr + mp->m_attr_geo->blksize;
434 for (i = 0, ent = entries; i < leafhdr.count; ent++, i++) {
435 /* Mark the leaf entry itself. */
436 off = (char *)ent - (char *)leaf;
437 if (!xchk_xattr_set_map(ds->sc, ab->usedmap, off,
438 sizeof(xfs_attr_leaf_entry_t))) {
439 xchk_da_set_corrupt(ds, level);
440 goto out;
441 }
442
443 /* Check the entry and nameval. */
444 xchk_xattr_entry(ds, level, buf_end, leaf, &leafhdr,
445 ent, i, &usedbytes, &last_hashval);
446
447 if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
448 goto out;
449 }
450
451 /* Construct bitmap of freemap contents. */
452 for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; i++) {
453 if (!xchk_xattr_set_map(ds->sc, ab->freemap,
454 leafhdr.freemap[i].base,
455 leafhdr.freemap[i].size))
456 xchk_da_set_corrupt(ds, level);
457
458 /*
459 * freemap entries with zero length and nonzero base can cause
460 * problems with older kernels, so we mark these for preening
461 * even though there's no inconsistency.
462 */
463 if (leafhdr.freemap[i].size == 0 &&
464 leafhdr.freemap[i].base > 0)
465 xchk_da_set_preen(ds, level);
466
467 if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
468 goto out;
469 }
470
471 /* Look for bits that are set in freemap and are marked in use. */
472 if (bitmap_intersects(ab->freemap, ab->usedmap,
473 mp->m_attr_geo->blksize))
474 xchk_da_set_corrupt(ds, level);
475
476 if (leafhdr.usedbytes != usedbytes)
477 xchk_da_set_corrupt(ds, level);
478
479 out:
480 return 0;
481 }
482
483 /* Scrub a attribute btree record. */
484 STATIC int
xchk_xattr_rec(struct xchk_da_btree * ds,int level)485 xchk_xattr_rec(
486 struct xchk_da_btree *ds,
487 int level)
488 {
489 struct xfs_mount *mp = ds->state->mp;
490 struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
491 struct xfs_attr_leaf_name_local *lentry;
492 struct xfs_attr_leaf_name_remote *rentry;
493 struct xfs_buf *bp;
494 struct xfs_attr_leaf_entry *ent;
495 xfs_dahash_t calc_hash;
496 xfs_dahash_t hash;
497 int nameidx;
498 int hdrsize;
499 int error;
500
501 ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
502
503 ent = xfs_attr3_leaf_entryp(blk->bp->b_addr) + blk->index;
504
505 /* Check the whole block, if necessary. */
506 error = xchk_xattr_block(ds, level);
507 if (error)
508 goto out;
509 if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
510 goto out;
511
512 /* Check the hash of the entry. */
513 error = xchk_da_btree_hash(ds, level, &ent->hashval);
514 if (error)
515 goto out;
516
517 /* Find the attr entry's location. */
518 bp = blk->bp;
519 hdrsize = xfs_attr3_leaf_hdr_size(bp->b_addr);
520 nameidx = be16_to_cpu(ent->nameidx);
521 if (nameidx < hdrsize || nameidx >= mp->m_attr_geo->blksize) {
522 xchk_da_set_corrupt(ds, level);
523 goto out;
524 }
525
526 /* Retrieve the entry and check it. */
527 hash = be32_to_cpu(ent->hashval);
528 if (ent->flags & ~XFS_ATTR_ONDISK_MASK) {
529 xchk_da_set_corrupt(ds, level);
530 return 0;
531 }
532 if (!xfs_attr_check_namespace(ent->flags)) {
533 xchk_da_set_corrupt(ds, level);
534 return 0;
535 }
536
537 if (ent->flags & XFS_ATTR_LOCAL) {
538 lentry = (struct xfs_attr_leaf_name_local *)
539 (((char *)bp->b_addr) + nameidx);
540 if (lentry->namelen <= 0) {
541 xchk_da_set_corrupt(ds, level);
542 goto out;
543 }
544 calc_hash = xfs_attr_hashval(mp, ent->flags, lentry->nameval,
545 lentry->namelen,
546 lentry->nameval + lentry->namelen,
547 be16_to_cpu(lentry->valuelen));
548 } else {
549 rentry = (struct xfs_attr_leaf_name_remote *)
550 (((char *)bp->b_addr) + nameidx);
551 if (rentry->namelen <= 0) {
552 xchk_da_set_corrupt(ds, level);
553 goto out;
554 }
555 if (ent->flags & XFS_ATTR_PARENT) {
556 xchk_da_set_corrupt(ds, level);
557 goto out;
558 }
559 calc_hash = xfs_attr_hashval(mp, ent->flags, rentry->name,
560 rentry->namelen, NULL,
561 be32_to_cpu(rentry->valuelen));
562 }
563 if (calc_hash != hash)
564 xchk_da_set_corrupt(ds, level);
565
566 out:
567 return error;
568 }
569
570 /* Check space usage of shortform attrs. */
571 STATIC int
xchk_xattr_check_sf(struct xfs_scrub * sc)572 xchk_xattr_check_sf(
573 struct xfs_scrub *sc)
574 {
575 struct xchk_xattr_buf *ab = sc->buf;
576 struct xfs_ifork *ifp = &sc->ip->i_af;
577 struct xfs_attr_sf_hdr *sf = ifp->if_data;
578 struct xfs_attr_sf_entry *sfe = xfs_attr_sf_firstentry(sf);
579 struct xfs_attr_sf_entry *next;
580 unsigned char *end = ifp->if_data + ifp->if_bytes;
581 int i;
582 int error = 0;
583
584 bitmap_zero(ab->usedmap, ifp->if_bytes);
585 xchk_xattr_set_map(sc, ab->usedmap, 0, sizeof(*sf));
586
587 if ((unsigned char *)sfe > end) {
588 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
589 return 0;
590 }
591
592 for (i = 0; i < sf->count; i++) {
593 unsigned char *name = sfe->nameval;
594 unsigned char *value = &sfe->nameval[sfe->namelen];
595
596 if (xchk_should_terminate(sc, &error))
597 return error;
598
599 next = xfs_attr_sf_nextentry(sfe);
600 if ((unsigned char *)next > end) {
601 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
602 break;
603 }
604
605 /*
606 * Shortform entries do not set LOCAL or INCOMPLETE, so the
607 * only valid flag bits here are for namespaces.
608 */
609 if (sfe->flags & ~XFS_ATTR_NSP_ONDISK_MASK) {
610 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
611 break;
612 }
613
614 if (!xchk_xattr_set_map(sc, ab->usedmap,
615 (char *)sfe - (char *)sf,
616 sizeof(struct xfs_attr_sf_entry))) {
617 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
618 break;
619 }
620
621 if (!xchk_xattr_set_map(sc, ab->usedmap,
622 (char *)name - (char *)sf,
623 sfe->namelen)) {
624 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
625 break;
626 }
627
628 if (!xchk_xattr_set_map(sc, ab->usedmap,
629 (char *)value - (char *)sf,
630 sfe->valuelen)) {
631 xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, 0);
632 break;
633 }
634
635 sfe = next;
636 }
637
638 return 0;
639 }
640
641 /* Scrub the extended attribute metadata. */
642 int
xchk_xattr(struct xfs_scrub * sc)643 xchk_xattr(
644 struct xfs_scrub *sc)
645 {
646 xfs_dablk_t last_checked = -1U;
647 int error = 0;
648
649 if (!xfs_inode_hasattr(sc->ip))
650 return -ENOENT;
651
652 /* Allocate memory for xattr checking. */
653 error = xchk_setup_xattr_buf(sc, 0);
654 if (error == -ENOMEM)
655 return -EDEADLOCK;
656 if (error)
657 return error;
658
659 /* Check the physical structure of the xattr. */
660 if (sc->ip->i_af.if_format == XFS_DINODE_FMT_LOCAL)
661 error = xchk_xattr_check_sf(sc);
662 else
663 error = xchk_da_btree(sc, XFS_ATTR_FORK, xchk_xattr_rec,
664 &last_checked);
665 if (error)
666 return error;
667
668 if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
669 return 0;
670
671 /*
672 * Look up every xattr in this file by name and hash.
673 *
674 * The VFS only locks i_rwsem when modifying attrs, so keep all
675 * three locks held because that's the only way to ensure we're
676 * the only thread poking into the da btree. We traverse the da
677 * btree while holding a leaf buffer locked for the xattr name
678 * iteration, which doesn't really follow the usual buffer
679 * locking order.
680 */
681 error = xchk_xattr_walk(sc, sc->ip, xchk_xattr_actor, NULL, NULL);
682 if (!xchk_fblock_process_error(sc, XFS_ATTR_FORK, 0, &error))
683 return error;
684
685 return 0;
686 }
687