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.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_btree.h"
13#include "xfs_log_format.h"
14#include "xfs_trans.h"
15#include "xfs_ag.h"
16#include "xfs_inode.h"
17#include "xfs_ialloc.h"
18#include "xfs_icache.h"
19#include "xfs_da_format.h"
20#include "xfs_reflink.h"
21#include "xfs_rmap.h"
22#include "xfs_bmap_util.h"
23#include "xfs_rtbitmap.h"
24#include "scrub/scrub.h"
25#include "scrub/common.h"
26#include "scrub/btree.h"
27#include "scrub/trace.h"
28#include "scrub/repair.h"
29
30/* Prepare the attached inode for scrubbing. */
31static inline int
32xchk_prepare_iscrub(
33	struct xfs_scrub	*sc)
34{
35	int			error;
36
37	xchk_ilock(sc, XFS_IOLOCK_EXCL);
38
39	error = xchk_trans_alloc(sc, 0);
40	if (error)
41		return error;
42
43	error = xchk_ino_dqattach(sc);
44	if (error)
45		return error;
46
47	xchk_ilock(sc, XFS_ILOCK_EXCL);
48	return 0;
49}
50
51/* Install this scrub-by-handle inode and prepare it for scrubbing. */
52static inline int
53xchk_install_handle_iscrub(
54	struct xfs_scrub	*sc,
55	struct xfs_inode	*ip)
56{
57	int			error;
58
59	error = xchk_install_handle_inode(sc, ip);
60	if (error)
61		return error;
62
63	return xchk_prepare_iscrub(sc);
64}
65
66/*
67 * Grab total control of the inode metadata.  In the best case, we grab the
68 * incore inode and take all locks on it.  If the incore inode cannot be
69 * constructed due to corruption problems, lock the AGI so that we can single
70 * step the loading process to fix everything that can go wrong.
71 */
72int
73xchk_setup_inode(
74	struct xfs_scrub	*sc)
75{
76	struct xfs_imap		imap;
77	struct xfs_inode	*ip;
78	struct xfs_mount	*mp = sc->mp;
79	struct xfs_inode	*ip_in = XFS_I(file_inode(sc->file));
80	struct xfs_buf		*agi_bp;
81	struct xfs_perag	*pag;
82	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, sc->sm->sm_ino);
83	int			error;
84
85	if (xchk_need_intent_drain(sc))
86		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
87
88	/* We want to scan the opened inode, so lock it and exit. */
89	if (sc->sm->sm_ino == 0 || sc->sm->sm_ino == ip_in->i_ino) {
90		error = xchk_install_live_inode(sc, ip_in);
91		if (error)
92			return error;
93
94		return xchk_prepare_iscrub(sc);
95	}
96
97	/* Reject internal metadata files and obviously bad inode numbers. */
98	if (xfs_internal_inum(mp, sc->sm->sm_ino))
99		return -ENOENT;
100	if (!xfs_verify_ino(sc->mp, sc->sm->sm_ino))
101		return -ENOENT;
102
103	/* Try a safe untrusted iget. */
104	error = xchk_iget_safe(sc, sc->sm->sm_ino, &ip);
105	if (!error)
106		return xchk_install_handle_iscrub(sc, ip);
107	if (error == -ENOENT)
108		return error;
109	if (error != -EFSCORRUPTED && error != -EFSBADCRC && error != -EINVAL)
110		goto out_error;
111
112	/*
113	 * EINVAL with IGET_UNTRUSTED probably means one of several things:
114	 * userspace gave us an inode number that doesn't correspond to fs
115	 * space; the inode btree lacks a record for this inode; or there is
116	 * a record, and it says this inode is free.
117	 *
118	 * EFSCORRUPTED/EFSBADCRC could mean that the inode was mappable, but
119	 * some other metadata corruption (e.g. inode forks) prevented
120	 * instantiation of the incore inode.  Or it could mean the inobt is
121	 * corrupt.
122	 *
123	 * We want to look up this inode in the inobt directly to distinguish
124	 * three different scenarios: (1) the inobt says the inode is free,
125	 * in which case there's nothing to do; (2) the inobt is corrupt so we
126	 * should flag the corruption and exit to userspace to let it fix the
127	 * inobt; and (3) the inobt says the inode is allocated, but loading it
128	 * failed due to corruption.
129	 *
130	 * Allocate a transaction and grab the AGI to prevent inobt activity in
131	 * this AG.  Retry the iget in case someone allocated a new inode after
132	 * the first iget failed.
133	 */
134	error = xchk_trans_alloc(sc, 0);
135	if (error)
136		goto out_error;
137
138	error = xchk_iget_agi(sc, sc->sm->sm_ino, &agi_bp, &ip);
139	if (error == 0) {
140		/* Actually got the incore inode, so install it and proceed. */
141		xchk_trans_cancel(sc);
142		return xchk_install_handle_iscrub(sc, ip);
143	}
144	if (error == -ENOENT)
145		goto out_gone;
146	if (error != -EFSCORRUPTED && error != -EFSBADCRC && error != -EINVAL)
147		goto out_cancel;
148
149	/* Ensure that we have protected against inode allocation/freeing. */
150	if (agi_bp == NULL) {
151		ASSERT(agi_bp != NULL);
152		error = -ECANCELED;
153		goto out_cancel;
154	}
155
156	/*
157	 * Untrusted iget failed a second time.  Let's try an inobt lookup.
158	 * If the inobt doesn't think this is an allocated inode then we'll
159	 * return ENOENT to signal that the check can be skipped.
160	 *
161	 * If the lookup signals corruption, we'll mark this inode corrupt and
162	 * exit to userspace.  There's little chance of fixing anything until
163	 * the inobt is straightened out, but there's nothing we can do here.
164	 *
165	 * If the lookup encounters a runtime error, exit to userspace.
166	 */
167	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sc->sm->sm_ino));
168	if (!pag) {
169		error = -EFSCORRUPTED;
170		goto out_cancel;
171	}
172
173	error = xfs_imap(pag, sc->tp, sc->sm->sm_ino, &imap,
174			XFS_IGET_UNTRUSTED);
175	xfs_perag_put(pag);
176	if (error == -EINVAL || error == -ENOENT)
177		goto out_gone;
178	if (error)
179		goto out_cancel;
180
181	/*
182	 * The lookup succeeded.  Chances are the ondisk inode is corrupt and
183	 * preventing iget from reading it.  Retain the scrub transaction and
184	 * the AGI buffer to prevent anyone from allocating or freeing inodes.
185	 * This ensures that we preserve the inconsistency between the inobt
186	 * saying the inode is allocated and the icache being unable to load
187	 * the inode until we can flag the corruption in xchk_inode.  The
188	 * scrub function has to note the corruption, since we're not really
189	 * supposed to do that from the setup function.  Save the mapping to
190	 * make repairs to the ondisk inode buffer.
191	 */
192	if (xchk_could_repair(sc))
193		xrep_setup_inode(sc, &imap);
194	return 0;
195
196out_cancel:
197	xchk_trans_cancel(sc);
198out_error:
199	trace_xchk_op_error(sc, agno, XFS_INO_TO_AGBNO(mp, sc->sm->sm_ino),
200			error, __return_address);
201	return error;
202out_gone:
203	/* The file is gone, so there's nothing to check. */
204	xchk_trans_cancel(sc);
205	return -ENOENT;
206}
207
208/* Inode core */
209
210/* Validate di_extsize hint. */
211STATIC void
212xchk_inode_extsize(
213	struct xfs_scrub	*sc,
214	struct xfs_dinode	*dip,
215	xfs_ino_t		ino,
216	uint16_t		mode,
217	uint16_t		flags)
218{
219	xfs_failaddr_t		fa;
220	uint32_t		value = be32_to_cpu(dip->di_extsize);
221
222	fa = xfs_inode_validate_extsize(sc->mp, value, mode, flags);
223	if (fa)
224		xchk_ino_set_corrupt(sc, ino);
225
226	/*
227	 * XFS allows a sysadmin to change the rt extent size when adding a rt
228	 * section to a filesystem after formatting.  If there are any
229	 * directories with extszinherit and rtinherit set, the hint could
230	 * become misaligned with the new rextsize.  The verifier doesn't check
231	 * this, because we allow rtinherit directories even without an rt
232	 * device.  Flag this as an administrative warning since we will clean
233	 * this up eventually.
234	 */
235	if ((flags & XFS_DIFLAG_RTINHERIT) &&
236	    (flags & XFS_DIFLAG_EXTSZINHERIT) &&
237	    xfs_extlen_to_rtxmod(sc->mp, value) > 0)
238		xchk_ino_set_warning(sc, ino);
239}
240
241/*
242 * Validate di_cowextsize hint.
243 *
244 * The rules are documented at xfs_ioctl_setattr_check_cowextsize().
245 * These functions must be kept in sync with each other.
246 */
247STATIC void
248xchk_inode_cowextsize(
249	struct xfs_scrub	*sc,
250	struct xfs_dinode	*dip,
251	xfs_ino_t		ino,
252	uint16_t		mode,
253	uint16_t		flags,
254	uint64_t		flags2)
255{
256	xfs_failaddr_t		fa;
257
258	fa = xfs_inode_validate_cowextsize(sc->mp,
259			be32_to_cpu(dip->di_cowextsize), mode, flags,
260			flags2);
261	if (fa)
262		xchk_ino_set_corrupt(sc, ino);
263}
264
265/* Make sure the di_flags make sense for the inode. */
266STATIC void
267xchk_inode_flags(
268	struct xfs_scrub	*sc,
269	struct xfs_dinode	*dip,
270	xfs_ino_t		ino,
271	uint16_t		mode,
272	uint16_t		flags)
273{
274	struct xfs_mount	*mp = sc->mp;
275
276	/* di_flags are all taken, last bit cannot be used */
277	if (flags & ~XFS_DIFLAG_ANY)
278		goto bad;
279
280	/* rt flags require rt device */
281	if ((flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
282		goto bad;
283
284	/* new rt bitmap flag only valid for rbmino */
285	if ((flags & XFS_DIFLAG_NEWRTBM) && ino != mp->m_sb.sb_rbmino)
286		goto bad;
287
288	/* directory-only flags */
289	if ((flags & (XFS_DIFLAG_RTINHERIT |
290		     XFS_DIFLAG_EXTSZINHERIT |
291		     XFS_DIFLAG_PROJINHERIT |
292		     XFS_DIFLAG_NOSYMLINKS)) &&
293	    !S_ISDIR(mode))
294		goto bad;
295
296	/* file-only flags */
297	if ((flags & (XFS_DIFLAG_REALTIME | FS_XFLAG_EXTSIZE)) &&
298	    !S_ISREG(mode))
299		goto bad;
300
301	/* filestreams and rt make no sense */
302	if ((flags & XFS_DIFLAG_FILESTREAM) && (flags & XFS_DIFLAG_REALTIME))
303		goto bad;
304
305	return;
306bad:
307	xchk_ino_set_corrupt(sc, ino);
308}
309
310/* Make sure the di_flags2 make sense for the inode. */
311STATIC void
312xchk_inode_flags2(
313	struct xfs_scrub	*sc,
314	struct xfs_dinode	*dip,
315	xfs_ino_t		ino,
316	uint16_t		mode,
317	uint16_t		flags,
318	uint64_t		flags2)
319{
320	struct xfs_mount	*mp = sc->mp;
321
322	/* Unknown di_flags2 could be from a future kernel */
323	if (flags2 & ~XFS_DIFLAG2_ANY)
324		xchk_ino_set_warning(sc, ino);
325
326	/* reflink flag requires reflink feature */
327	if ((flags2 & XFS_DIFLAG2_REFLINK) &&
328	    !xfs_has_reflink(mp))
329		goto bad;
330
331	/* cowextsize flag is checked w.r.t. mode separately */
332
333	/* file/dir-only flags */
334	if ((flags2 & XFS_DIFLAG2_DAX) && !(S_ISREG(mode) || S_ISDIR(mode)))
335		goto bad;
336
337	/* file-only flags */
338	if ((flags2 & XFS_DIFLAG2_REFLINK) && !S_ISREG(mode))
339		goto bad;
340
341	/* realtime and reflink make no sense, currently */
342	if ((flags & XFS_DIFLAG_REALTIME) && (flags2 & XFS_DIFLAG2_REFLINK))
343		goto bad;
344
345	/* no bigtime iflag without the bigtime feature */
346	if (xfs_dinode_has_bigtime(dip) && !xfs_has_bigtime(mp))
347		goto bad;
348
349	/* no large extent counts without the filesystem feature */
350	if ((flags2 & XFS_DIFLAG2_NREXT64) && !xfs_has_large_extent_counts(mp))
351		goto bad;
352
353	return;
354bad:
355	xchk_ino_set_corrupt(sc, ino);
356}
357
358static inline void
359xchk_dinode_nsec(
360	struct xfs_scrub	*sc,
361	xfs_ino_t		ino,
362	struct xfs_dinode	*dip,
363	const xfs_timestamp_t	ts)
364{
365	struct timespec64	tv;
366
367	tv = xfs_inode_from_disk_ts(dip, ts);
368	if (tv.tv_nsec < 0 || tv.tv_nsec >= NSEC_PER_SEC)
369		xchk_ino_set_corrupt(sc, ino);
370}
371
372/* Scrub all the ondisk inode fields. */
373STATIC void
374xchk_dinode(
375	struct xfs_scrub	*sc,
376	struct xfs_dinode	*dip,
377	xfs_ino_t		ino)
378{
379	struct xfs_mount	*mp = sc->mp;
380	size_t			fork_recs;
381	unsigned long long	isize;
382	uint64_t		flags2;
383	xfs_extnum_t		nextents;
384	xfs_extnum_t		naextents;
385	prid_t			prid;
386	uint16_t		flags;
387	uint16_t		mode;
388
389	flags = be16_to_cpu(dip->di_flags);
390	if (dip->di_version >= 3)
391		flags2 = be64_to_cpu(dip->di_flags2);
392	else
393		flags2 = 0;
394
395	/* di_mode */
396	mode = be16_to_cpu(dip->di_mode);
397	switch (mode & S_IFMT) {
398	case S_IFLNK:
399	case S_IFREG:
400	case S_IFDIR:
401	case S_IFCHR:
402	case S_IFBLK:
403	case S_IFIFO:
404	case S_IFSOCK:
405		/* mode is recognized */
406		break;
407	default:
408		xchk_ino_set_corrupt(sc, ino);
409		break;
410	}
411
412	/* v1/v2 fields */
413	switch (dip->di_version) {
414	case 1:
415		/*
416		 * We autoconvert v1 inodes into v2 inodes on writeout,
417		 * so just mark this inode for preening.
418		 */
419		xchk_ino_set_preen(sc, ino);
420		prid = 0;
421		break;
422	case 2:
423	case 3:
424		if (dip->di_onlink != 0)
425			xchk_ino_set_corrupt(sc, ino);
426
427		if (dip->di_mode == 0 && sc->ip)
428			xchk_ino_set_corrupt(sc, ino);
429
430		if (dip->di_projid_hi != 0 &&
431		    !xfs_has_projid32(mp))
432			xchk_ino_set_corrupt(sc, ino);
433
434		prid = be16_to_cpu(dip->di_projid_lo);
435		break;
436	default:
437		xchk_ino_set_corrupt(sc, ino);
438		return;
439	}
440
441	if (xfs_has_projid32(mp))
442		prid |= (prid_t)be16_to_cpu(dip->di_projid_hi) << 16;
443
444	/*
445	 * di_uid/di_gid -- -1 isn't invalid, but there's no way that
446	 * userspace could have created that.
447	 */
448	if (dip->di_uid == cpu_to_be32(-1U) ||
449	    dip->di_gid == cpu_to_be32(-1U))
450		xchk_ino_set_warning(sc, ino);
451
452	/*
453	 * project id of -1 isn't supposed to be valid, but the kernel didn't
454	 * always validate that.
455	 */
456	if (prid == -1U)
457		xchk_ino_set_warning(sc, ino);
458
459	/* di_format */
460	switch (dip->di_format) {
461	case XFS_DINODE_FMT_DEV:
462		if (!S_ISCHR(mode) && !S_ISBLK(mode) &&
463		    !S_ISFIFO(mode) && !S_ISSOCK(mode))
464			xchk_ino_set_corrupt(sc, ino);
465		break;
466	case XFS_DINODE_FMT_LOCAL:
467		if (!S_ISDIR(mode) && !S_ISLNK(mode))
468			xchk_ino_set_corrupt(sc, ino);
469		break;
470	case XFS_DINODE_FMT_EXTENTS:
471		if (!S_ISREG(mode) && !S_ISDIR(mode) && !S_ISLNK(mode))
472			xchk_ino_set_corrupt(sc, ino);
473		break;
474	case XFS_DINODE_FMT_BTREE:
475		if (!S_ISREG(mode) && !S_ISDIR(mode))
476			xchk_ino_set_corrupt(sc, ino);
477		break;
478	case XFS_DINODE_FMT_UUID:
479	default:
480		xchk_ino_set_corrupt(sc, ino);
481		break;
482	}
483
484	/* di_[amc]time.nsec */
485	xchk_dinode_nsec(sc, ino, dip, dip->di_atime);
486	xchk_dinode_nsec(sc, ino, dip, dip->di_mtime);
487	xchk_dinode_nsec(sc, ino, dip, dip->di_ctime);
488
489	/*
490	 * di_size.  xfs_dinode_verify checks for things that screw up
491	 * the VFS such as the upper bit being set and zero-length
492	 * symlinks/directories, but we can do more here.
493	 */
494	isize = be64_to_cpu(dip->di_size);
495	if (isize & (1ULL << 63))
496		xchk_ino_set_corrupt(sc, ino);
497
498	/* Devices, fifos, and sockets must have zero size */
499	if (!S_ISDIR(mode) && !S_ISREG(mode) && !S_ISLNK(mode) && isize != 0)
500		xchk_ino_set_corrupt(sc, ino);
501
502	/* Directories can't be larger than the data section size (32G) */
503	if (S_ISDIR(mode) && (isize == 0 || isize >= XFS_DIR2_SPACE_SIZE))
504		xchk_ino_set_corrupt(sc, ino);
505
506	/* Symlinks can't be larger than SYMLINK_MAXLEN */
507	if (S_ISLNK(mode) && (isize == 0 || isize >= XFS_SYMLINK_MAXLEN))
508		xchk_ino_set_corrupt(sc, ino);
509
510	/*
511	 * Warn if the running kernel can't handle the kinds of offsets
512	 * needed to deal with the file size.  In other words, if the
513	 * pagecache can't cache all the blocks in this file due to
514	 * overly large offsets, flag the inode for admin review.
515	 */
516	if (isize > mp->m_super->s_maxbytes)
517		xchk_ino_set_warning(sc, ino);
518
519	/* di_nblocks */
520	if (flags2 & XFS_DIFLAG2_REFLINK) {
521		; /* nblocks can exceed dblocks */
522	} else if (flags & XFS_DIFLAG_REALTIME) {
523		/*
524		 * nblocks is the sum of data extents (in the rtdev),
525		 * attr extents (in the datadev), and both forks' bmbt
526		 * blocks (in the datadev).  This clumsy check is the
527		 * best we can do without cross-referencing with the
528		 * inode forks.
529		 */
530		if (be64_to_cpu(dip->di_nblocks) >=
531		    mp->m_sb.sb_dblocks + mp->m_sb.sb_rblocks)
532			xchk_ino_set_corrupt(sc, ino);
533	} else {
534		if (be64_to_cpu(dip->di_nblocks) >= mp->m_sb.sb_dblocks)
535			xchk_ino_set_corrupt(sc, ino);
536	}
537
538	xchk_inode_flags(sc, dip, ino, mode, flags);
539
540	xchk_inode_extsize(sc, dip, ino, mode, flags);
541
542	nextents = xfs_dfork_data_extents(dip);
543	naextents = xfs_dfork_attr_extents(dip);
544
545	/* di_nextents */
546	fork_recs =  XFS_DFORK_DSIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
547	switch (dip->di_format) {
548	case XFS_DINODE_FMT_EXTENTS:
549		if (nextents > fork_recs)
550			xchk_ino_set_corrupt(sc, ino);
551		break;
552	case XFS_DINODE_FMT_BTREE:
553		if (nextents <= fork_recs)
554			xchk_ino_set_corrupt(sc, ino);
555		break;
556	default:
557		if (nextents != 0)
558			xchk_ino_set_corrupt(sc, ino);
559		break;
560	}
561
562	/* di_forkoff */
563	if (XFS_DFORK_BOFF(dip) >= mp->m_sb.sb_inodesize)
564		xchk_ino_set_corrupt(sc, ino);
565	if (naextents != 0 && dip->di_forkoff == 0)
566		xchk_ino_set_corrupt(sc, ino);
567	if (dip->di_forkoff == 0 && dip->di_aformat != XFS_DINODE_FMT_EXTENTS)
568		xchk_ino_set_corrupt(sc, ino);
569
570	/* di_aformat */
571	if (dip->di_aformat != XFS_DINODE_FMT_LOCAL &&
572	    dip->di_aformat != XFS_DINODE_FMT_EXTENTS &&
573	    dip->di_aformat != XFS_DINODE_FMT_BTREE)
574		xchk_ino_set_corrupt(sc, ino);
575
576	/* di_anextents */
577	fork_recs =  XFS_DFORK_ASIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
578	switch (dip->di_aformat) {
579	case XFS_DINODE_FMT_EXTENTS:
580		if (naextents > fork_recs)
581			xchk_ino_set_corrupt(sc, ino);
582		break;
583	case XFS_DINODE_FMT_BTREE:
584		if (naextents <= fork_recs)
585			xchk_ino_set_corrupt(sc, ino);
586		break;
587	default:
588		if (naextents != 0)
589			xchk_ino_set_corrupt(sc, ino);
590	}
591
592	if (dip->di_version >= 3) {
593		xchk_dinode_nsec(sc, ino, dip, dip->di_crtime);
594		xchk_inode_flags2(sc, dip, ino, mode, flags, flags2);
595		xchk_inode_cowextsize(sc, dip, ino, mode, flags,
596				flags2);
597	}
598}
599
600/*
601 * Make sure the finobt doesn't think this inode is free.
602 * We don't have to check the inobt ourselves because we got the inode via
603 * IGET_UNTRUSTED, which checks the inobt for us.
604 */
605static void
606xchk_inode_xref_finobt(
607	struct xfs_scrub		*sc,
608	xfs_ino_t			ino)
609{
610	struct xfs_inobt_rec_incore	rec;
611	xfs_agino_t			agino;
612	int				has_record;
613	int				error;
614
615	if (!sc->sa.fino_cur || xchk_skip_xref(sc->sm))
616		return;
617
618	agino = XFS_INO_TO_AGINO(sc->mp, ino);
619
620	/*
621	 * Try to get the finobt record.  If we can't get it, then we're
622	 * in good shape.
623	 */
624	error = xfs_inobt_lookup(sc->sa.fino_cur, agino, XFS_LOOKUP_LE,
625			&has_record);
626	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
627	    !has_record)
628		return;
629
630	error = xfs_inobt_get_rec(sc->sa.fino_cur, &rec, &has_record);
631	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
632	    !has_record)
633		return;
634
635	/*
636	 * Otherwise, make sure this record either doesn't cover this inode,
637	 * or that it does but it's marked present.
638	 */
639	if (rec.ir_startino > agino ||
640	    rec.ir_startino + XFS_INODES_PER_CHUNK <= agino)
641		return;
642
643	if (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino))
644		xchk_btree_xref_set_corrupt(sc, sc->sa.fino_cur, 0);
645}
646
647/* Cross reference the inode fields with the forks. */
648STATIC void
649xchk_inode_xref_bmap(
650	struct xfs_scrub	*sc,
651	struct xfs_dinode	*dip)
652{
653	xfs_extnum_t		nextents;
654	xfs_filblks_t		count;
655	xfs_filblks_t		acount;
656	int			error;
657
658	if (xchk_skip_xref(sc->sm))
659		return;
660
661	/* Walk all the extents to check nextents/naextents/nblocks. */
662	error = xfs_bmap_count_blocks(sc->tp, sc->ip, XFS_DATA_FORK,
663			&nextents, &count);
664	if (!xchk_should_check_xref(sc, &error, NULL))
665		return;
666	if (nextents < xfs_dfork_data_extents(dip))
667		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
668
669	error = xfs_bmap_count_blocks(sc->tp, sc->ip, XFS_ATTR_FORK,
670			&nextents, &acount);
671	if (!xchk_should_check_xref(sc, &error, NULL))
672		return;
673	if (nextents != xfs_dfork_attr_extents(dip))
674		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
675
676	/* Check nblocks against the inode. */
677	if (count + acount != be64_to_cpu(dip->di_nblocks))
678		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
679}
680
681/* Cross-reference with the other btrees. */
682STATIC void
683xchk_inode_xref(
684	struct xfs_scrub	*sc,
685	xfs_ino_t		ino,
686	struct xfs_dinode	*dip)
687{
688	xfs_agnumber_t		agno;
689	xfs_agblock_t		agbno;
690	int			error;
691
692	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
693		return;
694
695	agno = XFS_INO_TO_AGNO(sc->mp, ino);
696	agbno = XFS_INO_TO_AGBNO(sc->mp, ino);
697
698	error = xchk_ag_init_existing(sc, agno, &sc->sa);
699	if (!xchk_xref_process_error(sc, agno, agbno, &error))
700		goto out_free;
701
702	xchk_xref_is_used_space(sc, agbno, 1);
703	xchk_inode_xref_finobt(sc, ino);
704	xchk_xref_is_only_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_INODES);
705	xchk_xref_is_not_shared(sc, agbno, 1);
706	xchk_xref_is_not_cow_staging(sc, agbno, 1);
707	xchk_inode_xref_bmap(sc, dip);
708
709out_free:
710	xchk_ag_free(sc, &sc->sa);
711}
712
713/*
714 * If the reflink iflag disagrees with a scan for shared data fork extents,
715 * either flag an error (shared extents w/ no flag) or a preen (flag set w/o
716 * any shared extents).  We already checked for reflink iflag set on a non
717 * reflink filesystem.
718 */
719static void
720xchk_inode_check_reflink_iflag(
721	struct xfs_scrub	*sc,
722	xfs_ino_t		ino)
723{
724	struct xfs_mount	*mp = sc->mp;
725	bool			has_shared;
726	int			error;
727
728	if (!xfs_has_reflink(mp))
729		return;
730
731	error = xfs_reflink_inode_has_shared_extents(sc->tp, sc->ip,
732			&has_shared);
733	if (!xchk_xref_process_error(sc, XFS_INO_TO_AGNO(mp, ino),
734			XFS_INO_TO_AGBNO(mp, ino), &error))
735		return;
736	if (xfs_is_reflink_inode(sc->ip) && !has_shared)
737		xchk_ino_set_preen(sc, ino);
738	else if (!xfs_is_reflink_inode(sc->ip) && has_shared)
739		xchk_ino_set_corrupt(sc, ino);
740}
741
742/* Scrub an inode. */
743int
744xchk_inode(
745	struct xfs_scrub	*sc)
746{
747	struct xfs_dinode	di;
748	int			error = 0;
749
750	/*
751	 * If sc->ip is NULL, that means that the setup function called
752	 * xfs_iget to look up the inode.  xfs_iget returned a EFSCORRUPTED
753	 * and a NULL inode, so flag the corruption error and return.
754	 */
755	if (!sc->ip) {
756		xchk_ino_set_corrupt(sc, sc->sm->sm_ino);
757		return 0;
758	}
759
760	/* Scrub the inode core. */
761	xfs_inode_to_disk(sc->ip, &di, 0);
762	xchk_dinode(sc, &di, sc->ip->i_ino);
763	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
764		goto out;
765
766	/*
767	 * Look for discrepancies between file's data blocks and the reflink
768	 * iflag.  We already checked the iflag against the file mode when
769	 * we scrubbed the dinode.
770	 */
771	if (S_ISREG(VFS_I(sc->ip)->i_mode))
772		xchk_inode_check_reflink_iflag(sc, sc->ip->i_ino);
773
774	xchk_inode_xref(sc, sc->ip->i_ino, &di);
775out:
776	return error;
777}
778