xref: /linux/fs/xfs/scrub/inode.c (revision b477ff98d903618a1ab8247861f2ea6e70c0f0f8)
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. */
31 static inline int
xchk_prepare_iscrub(struct xfs_scrub * sc)32 xchk_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. */
52 static inline int
xchk_install_handle_iscrub(struct xfs_scrub * sc,struct xfs_inode * ip)53 xchk_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 	/*
64 	 * Don't allow scrubbing by handle of any non-directory inode records
65 	 * in the metadata directory tree.  We don't know if any of the scans
66 	 * launched by this scrubber will end up indirectly trying to lock this
67 	 * file.
68 	 *
69 	 * Scrubbers of inode-rooted metadata files (e.g. quota files) will
70 	 * attach all the resources needed to scrub the inode and call
71 	 * xchk_inode directly.  Userspace cannot call this directly.
72 	 */
73 	if (xfs_is_metadir_inode(ip) && !S_ISDIR(VFS_I(ip)->i_mode)) {
74 		xchk_irele(sc, ip);
75 		sc->ip = NULL;
76 		return -ENOENT;
77 	}
78 
79 	return xchk_prepare_iscrub(sc);
80 }
81 
82 /*
83  * Grab total control of the inode metadata.  In the best case, we grab the
84  * incore inode and take all locks on it.  If the incore inode cannot be
85  * constructed due to corruption problems, lock the AGI so that we can single
86  * step the loading process to fix everything that can go wrong.
87  */
88 int
xchk_setup_inode(struct xfs_scrub * sc)89 xchk_setup_inode(
90 	struct xfs_scrub	*sc)
91 {
92 	struct xfs_imap		imap;
93 	struct xfs_inode	*ip;
94 	struct xfs_mount	*mp = sc->mp;
95 	struct xfs_inode	*ip_in = XFS_I(file_inode(sc->file));
96 	struct xfs_buf		*agi_bp;
97 	struct xfs_perag	*pag;
98 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, sc->sm->sm_ino);
99 	int			error;
100 
101 	if (xchk_need_intent_drain(sc))
102 		xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN);
103 
104 	/* We want to scan the opened inode, so lock it and exit. */
105 	if (sc->sm->sm_ino == 0 || sc->sm->sm_ino == ip_in->i_ino) {
106 		error = xchk_install_live_inode(sc, ip_in);
107 		if (error)
108 			return error;
109 
110 		return xchk_prepare_iscrub(sc);
111 	}
112 
113 	/*
114 	 * On pre-metadir filesystems, reject internal metadata files.  For
115 	 * metadir filesystems, limited scrubbing of any file in the metadata
116 	 * directory tree by handle is allowed, because that is the only way to
117 	 * validate the lack of parent pointers in the sb-root metadata inodes.
118 	 */
119 	if (!xfs_has_metadir(mp) && xfs_is_sb_inum(mp, sc->sm->sm_ino))
120 		return -ENOENT;
121 	/* Reject obviously bad inode numbers. */
122 	if (!xfs_verify_ino(sc->mp, sc->sm->sm_ino))
123 		return -ENOENT;
124 
125 	/* Try a safe untrusted iget. */
126 	error = xchk_iget_safe(sc, sc->sm->sm_ino, &ip);
127 	if (!error)
128 		return xchk_install_handle_iscrub(sc, ip);
129 	if (error == -ENOENT)
130 		return error;
131 	if (error != -EFSCORRUPTED && error != -EFSBADCRC && error != -EINVAL)
132 		goto out_error;
133 
134 	/*
135 	 * EINVAL with IGET_UNTRUSTED probably means one of several things:
136 	 * userspace gave us an inode number that doesn't correspond to fs
137 	 * space; the inode btree lacks a record for this inode; or there is
138 	 * a record, and it says this inode is free.
139 	 *
140 	 * EFSCORRUPTED/EFSBADCRC could mean that the inode was mappable, but
141 	 * some other metadata corruption (e.g. inode forks) prevented
142 	 * instantiation of the incore inode.  Or it could mean the inobt is
143 	 * corrupt.
144 	 *
145 	 * We want to look up this inode in the inobt directly to distinguish
146 	 * three different scenarios: (1) the inobt says the inode is free,
147 	 * in which case there's nothing to do; (2) the inobt is corrupt so we
148 	 * should flag the corruption and exit to userspace to let it fix the
149 	 * inobt; and (3) the inobt says the inode is allocated, but loading it
150 	 * failed due to corruption.
151 	 *
152 	 * Allocate a transaction and grab the AGI to prevent inobt activity in
153 	 * this AG.  Retry the iget in case someone allocated a new inode after
154 	 * the first iget failed.
155 	 */
156 	error = xchk_trans_alloc(sc, 0);
157 	if (error)
158 		goto out_error;
159 
160 	error = xchk_iget_agi(sc, sc->sm->sm_ino, &agi_bp, &ip);
161 	if (error == 0) {
162 		/* Actually got the incore inode, so install it and proceed. */
163 		xchk_trans_cancel(sc);
164 		return xchk_install_handle_iscrub(sc, ip);
165 	}
166 	if (error == -ENOENT)
167 		goto out_gone;
168 	if (error != -EFSCORRUPTED && error != -EFSBADCRC && error != -EINVAL)
169 		goto out_cancel;
170 
171 	/* Ensure that we have protected against inode allocation/freeing. */
172 	if (agi_bp == NULL) {
173 		ASSERT(agi_bp != NULL);
174 		error = -ECANCELED;
175 		goto out_cancel;
176 	}
177 
178 	/*
179 	 * Untrusted iget failed a second time.  Let's try an inobt lookup.
180 	 * If the inobt doesn't think this is an allocated inode then we'll
181 	 * return ENOENT to signal that the check can be skipped.
182 	 *
183 	 * If the lookup signals corruption, we'll mark this inode corrupt and
184 	 * exit to userspace.  There's little chance of fixing anything until
185 	 * the inobt is straightened out, but there's nothing we can do here.
186 	 *
187 	 * If the lookup encounters a runtime error, exit to userspace.
188 	 */
189 	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sc->sm->sm_ino));
190 	if (!pag) {
191 		error = -EFSCORRUPTED;
192 		goto out_cancel;
193 	}
194 
195 	error = xfs_imap(pag, sc->tp, sc->sm->sm_ino, &imap,
196 			XFS_IGET_UNTRUSTED);
197 	xfs_perag_put(pag);
198 	if (error == -EINVAL || error == -ENOENT)
199 		goto out_gone;
200 	if (error)
201 		goto out_cancel;
202 
203 	/*
204 	 * The lookup succeeded.  Chances are the ondisk inode is corrupt and
205 	 * preventing iget from reading it.  Retain the scrub transaction and
206 	 * the AGI buffer to prevent anyone from allocating or freeing inodes.
207 	 * This ensures that we preserve the inconsistency between the inobt
208 	 * saying the inode is allocated and the icache being unable to load
209 	 * the inode until we can flag the corruption in xchk_inode.  The
210 	 * scrub function has to note the corruption, since we're not really
211 	 * supposed to do that from the setup function.  Save the mapping to
212 	 * make repairs to the ondisk inode buffer.
213 	 */
214 	if (xchk_could_repair(sc))
215 		xrep_setup_inode(sc, &imap);
216 	return 0;
217 
218 out_cancel:
219 	xchk_trans_cancel(sc);
220 out_error:
221 	trace_xchk_op_error(sc, agno, XFS_INO_TO_AGBNO(mp, sc->sm->sm_ino),
222 			error, __return_address);
223 	return error;
224 out_gone:
225 	/* The file is gone, so there's nothing to check. */
226 	xchk_trans_cancel(sc);
227 	return -ENOENT;
228 }
229 
230 /* Inode core */
231 
232 /* Validate di_extsize hint. */
233 STATIC void
xchk_inode_extsize(struct xfs_scrub * sc,struct xfs_dinode * dip,xfs_ino_t ino,uint16_t mode,uint16_t flags)234 xchk_inode_extsize(
235 	struct xfs_scrub	*sc,
236 	struct xfs_dinode	*dip,
237 	xfs_ino_t		ino,
238 	uint16_t		mode,
239 	uint16_t		flags)
240 {
241 	xfs_failaddr_t		fa;
242 	uint32_t		value = be32_to_cpu(dip->di_extsize);
243 
244 	fa = xfs_inode_validate_extsize(sc->mp, value, mode, flags);
245 	if (fa)
246 		xchk_ino_set_corrupt(sc, ino);
247 
248 	/*
249 	 * XFS allows a sysadmin to change the rt extent size when adding a rt
250 	 * section to a filesystem after formatting.  If there are any
251 	 * directories with extszinherit and rtinherit set, the hint could
252 	 * become misaligned with the new rextsize.  The verifier doesn't check
253 	 * this, because we allow rtinherit directories even without an rt
254 	 * device.  Flag this as an administrative warning since we will clean
255 	 * this up eventually.
256 	 */
257 	if ((flags & XFS_DIFLAG_RTINHERIT) &&
258 	    (flags & XFS_DIFLAG_EXTSZINHERIT) &&
259 	    xfs_extlen_to_rtxmod(sc->mp, value) > 0)
260 		xchk_ino_set_warning(sc, ino);
261 }
262 
263 /* Validate di_cowextsize hint. */
264 STATIC void
xchk_inode_cowextsize(struct xfs_scrub * sc,struct xfs_dinode * dip,xfs_ino_t ino,uint16_t mode,uint16_t flags,uint64_t flags2)265 xchk_inode_cowextsize(
266 	struct xfs_scrub	*sc,
267 	struct xfs_dinode	*dip,
268 	xfs_ino_t		ino,
269 	uint16_t		mode,
270 	uint16_t		flags,
271 	uint64_t		flags2)
272 {
273 	xfs_failaddr_t		fa;
274 	uint32_t		value = be32_to_cpu(dip->di_cowextsize);
275 
276 	fa = xfs_inode_validate_cowextsize(sc->mp, value, mode, flags, flags2);
277 	if (fa)
278 		xchk_ino_set_corrupt(sc, ino);
279 
280 	/*
281 	 * XFS allows a sysadmin to change the rt extent size when adding a rt
282 	 * section to a filesystem after formatting.  If there are any
283 	 * directories with cowextsize and rtinherit set, the hint could become
284 	 * misaligned with the new rextsize.  The verifier doesn't check this,
285 	 * because we allow rtinherit directories even without an rt device.
286 	 * Flag this as an administrative warning since we will clean this up
287 	 * eventually.
288 	 */
289 	if ((flags & XFS_DIFLAG_RTINHERIT) &&
290 	    (flags2 & XFS_DIFLAG2_COWEXTSIZE) &&
291 	    value % sc->mp->m_sb.sb_rextsize > 0)
292 		xchk_ino_set_warning(sc, ino);
293 }
294 
295 /* Make sure the di_flags make sense for the inode. */
296 STATIC void
xchk_inode_flags(struct xfs_scrub * sc,struct xfs_dinode * dip,xfs_ino_t ino,uint16_t mode,uint16_t flags)297 xchk_inode_flags(
298 	struct xfs_scrub	*sc,
299 	struct xfs_dinode	*dip,
300 	xfs_ino_t		ino,
301 	uint16_t		mode,
302 	uint16_t		flags)
303 {
304 	struct xfs_mount	*mp = sc->mp;
305 
306 	/* di_flags are all taken, last bit cannot be used */
307 	if (flags & ~XFS_DIFLAG_ANY)
308 		goto bad;
309 
310 	/* rt flags require rt device */
311 	if ((flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
312 		goto bad;
313 
314 	/* new rt bitmap flag only valid for rbmino */
315 	if ((flags & XFS_DIFLAG_NEWRTBM) && ino != mp->m_sb.sb_rbmino)
316 		goto bad;
317 
318 	/* directory-only flags */
319 	if ((flags & (XFS_DIFLAG_RTINHERIT |
320 		     XFS_DIFLAG_EXTSZINHERIT |
321 		     XFS_DIFLAG_PROJINHERIT |
322 		     XFS_DIFLAG_NOSYMLINKS)) &&
323 	    !S_ISDIR(mode))
324 		goto bad;
325 
326 	/* file-only flags */
327 	if ((flags & (XFS_DIFLAG_REALTIME | FS_XFLAG_EXTSIZE)) &&
328 	    !S_ISREG(mode))
329 		goto bad;
330 
331 	/* filestreams and rt make no sense */
332 	if ((flags & XFS_DIFLAG_FILESTREAM) && (flags & XFS_DIFLAG_REALTIME))
333 		goto bad;
334 
335 	return;
336 bad:
337 	xchk_ino_set_corrupt(sc, ino);
338 }
339 
340 /* Make sure the di_flags2 make sense for the inode. */
341 STATIC void
xchk_inode_flags2(struct xfs_scrub * sc,struct xfs_dinode * dip,xfs_ino_t ino,uint16_t mode,uint16_t flags,uint64_t flags2)342 xchk_inode_flags2(
343 	struct xfs_scrub	*sc,
344 	struct xfs_dinode	*dip,
345 	xfs_ino_t		ino,
346 	uint16_t		mode,
347 	uint16_t		flags,
348 	uint64_t		flags2)
349 {
350 	struct xfs_mount	*mp = sc->mp;
351 
352 	/* Unknown di_flags2 could be from a future kernel */
353 	if (flags2 & ~XFS_DIFLAG2_ANY)
354 		xchk_ino_set_warning(sc, ino);
355 
356 	/* reflink flag requires reflink feature */
357 	if ((flags2 & XFS_DIFLAG2_REFLINK) &&
358 	    !xfs_has_reflink(mp))
359 		goto bad;
360 
361 	/* cowextsize flag is checked w.r.t. mode separately */
362 
363 	/* file/dir-only flags */
364 	if ((flags2 & XFS_DIFLAG2_DAX) && !(S_ISREG(mode) || S_ISDIR(mode)))
365 		goto bad;
366 
367 	/* file-only flags */
368 	if ((flags2 & XFS_DIFLAG2_REFLINK) && !S_ISREG(mode))
369 		goto bad;
370 
371 	/* realtime and reflink don't always go together */
372 	if ((flags & XFS_DIFLAG_REALTIME) && (flags2 & XFS_DIFLAG2_REFLINK) &&
373 	    !xfs_has_rtreflink(mp))
374 		goto bad;
375 
376 	/* no bigtime iflag without the bigtime feature */
377 	if (xfs_dinode_has_bigtime(dip) && !xfs_has_bigtime(mp))
378 		goto bad;
379 
380 	/* no large extent counts without the filesystem feature */
381 	if ((flags2 & XFS_DIFLAG2_NREXT64) && !xfs_has_large_extent_counts(mp))
382 		goto bad;
383 
384 	return;
385 bad:
386 	xchk_ino_set_corrupt(sc, ino);
387 }
388 
389 static inline void
xchk_dinode_nsec(struct xfs_scrub * sc,xfs_ino_t ino,struct xfs_dinode * dip,const xfs_timestamp_t ts)390 xchk_dinode_nsec(
391 	struct xfs_scrub	*sc,
392 	xfs_ino_t		ino,
393 	struct xfs_dinode	*dip,
394 	const xfs_timestamp_t	ts)
395 {
396 	struct timespec64	tv;
397 
398 	tv = xfs_inode_from_disk_ts(dip, ts);
399 	if (tv.tv_nsec < 0 || tv.tv_nsec >= NSEC_PER_SEC)
400 		xchk_ino_set_corrupt(sc, ino);
401 }
402 
403 /* Scrub all the ondisk inode fields. */
404 STATIC void
xchk_dinode(struct xfs_scrub * sc,struct xfs_dinode * dip,xfs_ino_t ino)405 xchk_dinode(
406 	struct xfs_scrub	*sc,
407 	struct xfs_dinode	*dip,
408 	xfs_ino_t		ino)
409 {
410 	struct xfs_mount	*mp = sc->mp;
411 	size_t			fork_recs;
412 	unsigned long long	isize;
413 	uint64_t		flags2;
414 	xfs_extnum_t		nextents;
415 	xfs_extnum_t		naextents;
416 	prid_t			prid;
417 	uint16_t		flags;
418 	uint16_t		mode;
419 
420 	flags = be16_to_cpu(dip->di_flags);
421 	if (dip->di_version >= 3)
422 		flags2 = be64_to_cpu(dip->di_flags2);
423 	else
424 		flags2 = 0;
425 
426 	/* di_mode */
427 	mode = be16_to_cpu(dip->di_mode);
428 	switch (mode & S_IFMT) {
429 	case S_IFLNK:
430 	case S_IFREG:
431 	case S_IFDIR:
432 	case S_IFCHR:
433 	case S_IFBLK:
434 	case S_IFIFO:
435 	case S_IFSOCK:
436 		/* mode is recognized */
437 		break;
438 	default:
439 		xchk_ino_set_corrupt(sc, ino);
440 		break;
441 	}
442 
443 	/* v1/v2 fields */
444 	switch (dip->di_version) {
445 	case 1:
446 		/*
447 		 * We autoconvert v1 inodes into v2 inodes on writeout,
448 		 * so just mark this inode for preening.
449 		 */
450 		xchk_ino_set_preen(sc, ino);
451 		prid = 0;
452 		break;
453 	case 2:
454 	case 3:
455 		if (xfs_dinode_is_metadir(dip)) {
456 			if (be16_to_cpu(dip->di_metatype) >= XFS_METAFILE_MAX)
457 				xchk_ino_set_corrupt(sc, ino);
458 		} else {
459 			if (dip->di_metatype != 0)
460 				xchk_ino_set_corrupt(sc, ino);
461 		}
462 
463 		if (dip->di_mode == 0 && sc->ip)
464 			xchk_ino_set_corrupt(sc, ino);
465 
466 		if (dip->di_projid_hi != 0 &&
467 		    !xfs_has_projid32(mp))
468 			xchk_ino_set_corrupt(sc, ino);
469 
470 		prid = be16_to_cpu(dip->di_projid_lo);
471 		break;
472 	default:
473 		xchk_ino_set_corrupt(sc, ino);
474 		return;
475 	}
476 
477 	if (xfs_has_projid32(mp))
478 		prid |= (prid_t)be16_to_cpu(dip->di_projid_hi) << 16;
479 
480 	/*
481 	 * di_uid/di_gid -- -1 isn't invalid, but there's no way that
482 	 * userspace could have created that.
483 	 */
484 	if (dip->di_uid == cpu_to_be32(-1U) ||
485 	    dip->di_gid == cpu_to_be32(-1U))
486 		xchk_ino_set_warning(sc, ino);
487 
488 	/*
489 	 * project id of -1 isn't supposed to be valid, but the kernel didn't
490 	 * always validate that.
491 	 */
492 	if (prid == -1U)
493 		xchk_ino_set_warning(sc, ino);
494 
495 	/* di_format */
496 	switch (dip->di_format) {
497 	case XFS_DINODE_FMT_DEV:
498 		if (!S_ISCHR(mode) && !S_ISBLK(mode) &&
499 		    !S_ISFIFO(mode) && !S_ISSOCK(mode))
500 			xchk_ino_set_corrupt(sc, ino);
501 		break;
502 	case XFS_DINODE_FMT_LOCAL:
503 		if (!S_ISDIR(mode) && !S_ISLNK(mode))
504 			xchk_ino_set_corrupt(sc, ino);
505 		break;
506 	case XFS_DINODE_FMT_EXTENTS:
507 		if (!S_ISREG(mode) && !S_ISDIR(mode) && !S_ISLNK(mode))
508 			xchk_ino_set_corrupt(sc, ino);
509 		break;
510 	case XFS_DINODE_FMT_BTREE:
511 		if (!S_ISREG(mode) && !S_ISDIR(mode))
512 			xchk_ino_set_corrupt(sc, ino);
513 		break;
514 	case XFS_DINODE_FMT_META_BTREE:
515 		if (!S_ISREG(mode))
516 			xchk_ino_set_corrupt(sc, ino);
517 		break;
518 	case XFS_DINODE_FMT_UUID:
519 	default:
520 		xchk_ino_set_corrupt(sc, ino);
521 		break;
522 	}
523 
524 	/* di_[amc]time.nsec */
525 	xchk_dinode_nsec(sc, ino, dip, dip->di_atime);
526 	xchk_dinode_nsec(sc, ino, dip, dip->di_mtime);
527 	xchk_dinode_nsec(sc, ino, dip, dip->di_ctime);
528 
529 	/*
530 	 * di_size.  xfs_dinode_verify checks for things that screw up
531 	 * the VFS such as the upper bit being set and zero-length
532 	 * symlinks/directories, but we can do more here.
533 	 */
534 	isize = be64_to_cpu(dip->di_size);
535 	if (isize & (1ULL << 63))
536 		xchk_ino_set_corrupt(sc, ino);
537 
538 	/* Devices, fifos, and sockets must have zero size */
539 	if (!S_ISDIR(mode) && !S_ISREG(mode) && !S_ISLNK(mode) && isize != 0)
540 		xchk_ino_set_corrupt(sc, ino);
541 
542 	/* Directories can't be larger than the data section size (32G) */
543 	if (S_ISDIR(mode) && (isize == 0 || isize >= XFS_DIR2_SPACE_SIZE))
544 		xchk_ino_set_corrupt(sc, ino);
545 
546 	/* Symlinks can't be larger than SYMLINK_MAXLEN */
547 	if (S_ISLNK(mode) && (isize == 0 || isize >= XFS_SYMLINK_MAXLEN))
548 		xchk_ino_set_corrupt(sc, ino);
549 
550 	/*
551 	 * Warn if the running kernel can't handle the kinds of offsets
552 	 * needed to deal with the file size.  In other words, if the
553 	 * pagecache can't cache all the blocks in this file due to
554 	 * overly large offsets, flag the inode for admin review.
555 	 */
556 	if (isize > mp->m_super->s_maxbytes)
557 		xchk_ino_set_warning(sc, ino);
558 
559 	/* di_nblocks */
560 	if (flags2 & XFS_DIFLAG2_REFLINK) {
561 		; /* nblocks can exceed dblocks */
562 	} else if (flags & XFS_DIFLAG_REALTIME) {
563 		/*
564 		 * nblocks is the sum of data extents (in the rtdev),
565 		 * attr extents (in the datadev), and both forks' bmbt
566 		 * blocks (in the datadev).  This clumsy check is the
567 		 * best we can do without cross-referencing with the
568 		 * inode forks.
569 		 */
570 		if (be64_to_cpu(dip->di_nblocks) >=
571 		    mp->m_sb.sb_dblocks + mp->m_sb.sb_rblocks)
572 			xchk_ino_set_corrupt(sc, ino);
573 	} else {
574 		if (be64_to_cpu(dip->di_nblocks) >= mp->m_sb.sb_dblocks)
575 			xchk_ino_set_corrupt(sc, ino);
576 	}
577 
578 	xchk_inode_flags(sc, dip, ino, mode, flags);
579 
580 	xchk_inode_extsize(sc, dip, ino, mode, flags);
581 
582 	nextents = xfs_dfork_data_extents(dip);
583 	naextents = xfs_dfork_attr_extents(dip);
584 
585 	/* di_nextents */
586 	fork_recs =  XFS_DFORK_DSIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
587 	switch (dip->di_format) {
588 	case XFS_DINODE_FMT_EXTENTS:
589 		if (nextents > fork_recs)
590 			xchk_ino_set_corrupt(sc, ino);
591 		break;
592 	case XFS_DINODE_FMT_BTREE:
593 		if (nextents <= fork_recs)
594 			xchk_ino_set_corrupt(sc, ino);
595 		break;
596 	default:
597 		if (nextents != 0)
598 			xchk_ino_set_corrupt(sc, ino);
599 		break;
600 	}
601 
602 	/* di_forkoff */
603 	if (XFS_DFORK_BOFF(dip) >= mp->m_sb.sb_inodesize)
604 		xchk_ino_set_corrupt(sc, ino);
605 	if (naextents != 0 && dip->di_forkoff == 0)
606 		xchk_ino_set_corrupt(sc, ino);
607 	if (dip->di_forkoff == 0 && dip->di_aformat != XFS_DINODE_FMT_EXTENTS)
608 		xchk_ino_set_corrupt(sc, ino);
609 
610 	/* di_aformat */
611 	if (dip->di_aformat != XFS_DINODE_FMT_LOCAL &&
612 	    dip->di_aformat != XFS_DINODE_FMT_EXTENTS &&
613 	    dip->di_aformat != XFS_DINODE_FMT_BTREE)
614 		xchk_ino_set_corrupt(sc, ino);
615 
616 	/* di_anextents */
617 	fork_recs =  XFS_DFORK_ASIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
618 	switch (dip->di_aformat) {
619 	case XFS_DINODE_FMT_EXTENTS:
620 		if (naextents > fork_recs)
621 			xchk_ino_set_corrupt(sc, ino);
622 		break;
623 	case XFS_DINODE_FMT_BTREE:
624 		if (naextents <= fork_recs)
625 			xchk_ino_set_corrupt(sc, ino);
626 		break;
627 	default:
628 		if (naextents != 0)
629 			xchk_ino_set_corrupt(sc, ino);
630 	}
631 
632 	if (dip->di_version >= 3) {
633 		xchk_dinode_nsec(sc, ino, dip, dip->di_crtime);
634 		xchk_inode_flags2(sc, dip, ino, mode, flags, flags2);
635 		xchk_inode_cowextsize(sc, dip, ino, mode, flags,
636 				flags2);
637 	}
638 }
639 
640 /*
641  * Make sure the finobt doesn't think this inode is free.
642  * We don't have to check the inobt ourselves because we got the inode via
643  * IGET_UNTRUSTED, which checks the inobt for us.
644  */
645 static void
xchk_inode_xref_finobt(struct xfs_scrub * sc,xfs_ino_t ino)646 xchk_inode_xref_finobt(
647 	struct xfs_scrub		*sc,
648 	xfs_ino_t			ino)
649 {
650 	struct xfs_inobt_rec_incore	rec;
651 	xfs_agino_t			agino;
652 	int				has_record;
653 	int				error;
654 
655 	if (!sc->sa.fino_cur || xchk_skip_xref(sc->sm))
656 		return;
657 
658 	agino = XFS_INO_TO_AGINO(sc->mp, ino);
659 
660 	/*
661 	 * Try to get the finobt record.  If we can't get it, then we're
662 	 * in good shape.
663 	 */
664 	error = xfs_inobt_lookup(sc->sa.fino_cur, agino, XFS_LOOKUP_LE,
665 			&has_record);
666 	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
667 	    !has_record)
668 		return;
669 
670 	error = xfs_inobt_get_rec(sc->sa.fino_cur, &rec, &has_record);
671 	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
672 	    !has_record)
673 		return;
674 
675 	/*
676 	 * Otherwise, make sure this record either doesn't cover this inode,
677 	 * or that it does but it's marked present.
678 	 */
679 	if (rec.ir_startino > agino ||
680 	    rec.ir_startino + XFS_INODES_PER_CHUNK <= agino)
681 		return;
682 
683 	if (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino))
684 		xchk_btree_xref_set_corrupt(sc, sc->sa.fino_cur, 0);
685 }
686 
687 /* Cross reference the inode fields with the forks. */
688 STATIC void
xchk_inode_xref_bmap(struct xfs_scrub * sc,struct xfs_dinode * dip)689 xchk_inode_xref_bmap(
690 	struct xfs_scrub	*sc,
691 	struct xfs_dinode	*dip)
692 {
693 	xfs_extnum_t		nextents;
694 	xfs_filblks_t		count;
695 	xfs_filblks_t		acount;
696 	int			error;
697 
698 	if (xchk_skip_xref(sc->sm))
699 		return;
700 
701 	/* Walk all the extents to check nextents/naextents/nblocks. */
702 	error = xchk_inode_count_blocks(sc, XFS_DATA_FORK, &nextents, &count);
703 	if (!xchk_should_check_xref(sc, &error, NULL))
704 		return;
705 	if (nextents < xfs_dfork_data_extents(dip))
706 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
707 
708 	error = xchk_inode_count_blocks(sc, XFS_ATTR_FORK, &nextents, &acount);
709 	if (!xchk_should_check_xref(sc, &error, NULL))
710 		return;
711 	if (nextents != xfs_dfork_attr_extents(dip))
712 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
713 
714 	/* Check nblocks against the inode. */
715 	if (count + acount != be64_to_cpu(dip->di_nblocks))
716 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
717 }
718 
719 /* Cross-reference with the other btrees. */
720 STATIC void
xchk_inode_xref(struct xfs_scrub * sc,xfs_ino_t ino,struct xfs_dinode * dip)721 xchk_inode_xref(
722 	struct xfs_scrub	*sc,
723 	xfs_ino_t		ino,
724 	struct xfs_dinode	*dip)
725 {
726 	xfs_agnumber_t		agno;
727 	xfs_agblock_t		agbno;
728 	int			error;
729 
730 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
731 		return;
732 
733 	agno = XFS_INO_TO_AGNO(sc->mp, ino);
734 	agbno = XFS_INO_TO_AGBNO(sc->mp, ino);
735 
736 	error = xchk_ag_init_existing(sc, agno, &sc->sa);
737 	if (!xchk_xref_process_error(sc, agno, agbno, &error))
738 		goto out_free;
739 
740 	xchk_xref_is_used_space(sc, agbno, 1);
741 	xchk_inode_xref_finobt(sc, ino);
742 	xchk_xref_is_only_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_INODES);
743 	xchk_xref_is_not_shared(sc, agbno, 1);
744 	xchk_xref_is_not_cow_staging(sc, agbno, 1);
745 	xchk_inode_xref_bmap(sc, dip);
746 
747 out_free:
748 	xchk_ag_free(sc, &sc->sa);
749 }
750 
751 /*
752  * If the reflink iflag disagrees with a scan for shared data fork extents,
753  * either flag an error (shared extents w/ no flag) or a preen (flag set w/o
754  * any shared extents).  We already checked for reflink iflag set on a non
755  * reflink filesystem.
756  */
757 static void
xchk_inode_check_reflink_iflag(struct xfs_scrub * sc,xfs_ino_t ino)758 xchk_inode_check_reflink_iflag(
759 	struct xfs_scrub	*sc,
760 	xfs_ino_t		ino)
761 {
762 	struct xfs_mount	*mp = sc->mp;
763 	bool			has_shared;
764 	int			error;
765 
766 	if (!xfs_has_reflink(mp))
767 		return;
768 
769 	error = xfs_reflink_inode_has_shared_extents(sc->tp, sc->ip,
770 			&has_shared);
771 	if (!xchk_xref_process_error(sc, XFS_INO_TO_AGNO(mp, ino),
772 			XFS_INO_TO_AGBNO(mp, ino), &error))
773 		return;
774 	if (xfs_is_reflink_inode(sc->ip) && !has_shared)
775 		xchk_ino_set_preen(sc, ino);
776 	else if (!xfs_is_reflink_inode(sc->ip) && has_shared)
777 		xchk_ino_set_corrupt(sc, ino);
778 }
779 
780 /*
781  * If this inode has zero link count, it must be on the unlinked list.  If
782  * it has nonzero link count, it must not be on the unlinked list.
783  */
784 STATIC void
xchk_inode_check_unlinked(struct xfs_scrub * sc)785 xchk_inode_check_unlinked(
786 	struct xfs_scrub	*sc)
787 {
788 	if (VFS_I(sc->ip)->i_nlink == 0) {
789 		if (!xfs_inode_on_unlinked_list(sc->ip))
790 			xchk_ino_set_corrupt(sc, sc->ip->i_ino);
791 	} else {
792 		if (xfs_inode_on_unlinked_list(sc->ip))
793 			xchk_ino_set_corrupt(sc, sc->ip->i_ino);
794 	}
795 }
796 
797 /* Scrub an inode. */
798 int
xchk_inode(struct xfs_scrub * sc)799 xchk_inode(
800 	struct xfs_scrub	*sc)
801 {
802 	struct xfs_dinode	di;
803 	int			error = 0;
804 
805 	/*
806 	 * If sc->ip is NULL, that means that the setup function called
807 	 * xfs_iget to look up the inode.  xfs_iget returned a EFSCORRUPTED
808 	 * and a NULL inode, so flag the corruption error and return.
809 	 */
810 	if (!sc->ip) {
811 		xchk_ino_set_corrupt(sc, sc->sm->sm_ino);
812 		return 0;
813 	}
814 
815 	/* Scrub the inode core. */
816 	xfs_inode_to_disk(sc->ip, &di, 0);
817 	xchk_dinode(sc, &di, sc->ip->i_ino);
818 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
819 		goto out;
820 
821 	/*
822 	 * Look for discrepancies between file's data blocks and the reflink
823 	 * iflag.  We already checked the iflag against the file mode when
824 	 * we scrubbed the dinode.
825 	 */
826 	if (S_ISREG(VFS_I(sc->ip)->i_mode))
827 		xchk_inode_check_reflink_iflag(sc, sc->ip->i_ino);
828 
829 	xchk_inode_check_unlinked(sc);
830 
831 	xchk_inode_xref(sc, sc->ip->i_ino, &di);
832 out:
833 	return error;
834 }
835