xref: /openbmc/linux/fs/xfs/scrub/inode.c (revision 7280feda)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
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_defer.h"
13 #include "xfs_btree.h"
14 #include "xfs_bit.h"
15 #include "xfs_log_format.h"
16 #include "xfs_trans.h"
17 #include "xfs_sb.h"
18 #include "xfs_inode.h"
19 #include "xfs_icache.h"
20 #include "xfs_inode_buf.h"
21 #include "xfs_inode_fork.h"
22 #include "xfs_ialloc.h"
23 #include "xfs_da_format.h"
24 #include "xfs_reflink.h"
25 #include "xfs_rmap.h"
26 #include "xfs_bmap.h"
27 #include "xfs_bmap_util.h"
28 #include "scrub/xfs_scrub.h"
29 #include "scrub/scrub.h"
30 #include "scrub/common.h"
31 #include "scrub/btree.h"
32 #include "scrub/trace.h"
33 
34 /*
35  * Grab total control of the inode metadata.  It doesn't matter here if
36  * the file data is still changing; exclusive access to the metadata is
37  * the goal.
38  */
39 int
40 xchk_setup_inode(
41 	struct xfs_scrub	*sc,
42 	struct xfs_inode	*ip)
43 {
44 	int			error;
45 
46 	/*
47 	 * Try to get the inode.  If the verifiers fail, we try again
48 	 * in raw mode.
49 	 */
50 	error = xchk_get_inode(sc, ip);
51 	switch (error) {
52 	case 0:
53 		break;
54 	case -EFSCORRUPTED:
55 	case -EFSBADCRC:
56 		return xchk_trans_alloc(sc, 0);
57 	default:
58 		return error;
59 	}
60 
61 	/* Got the inode, lock it and we're ready to go. */
62 	sc->ilock_flags = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL;
63 	xfs_ilock(sc->ip, sc->ilock_flags);
64 	error = xchk_trans_alloc(sc, 0);
65 	if (error)
66 		goto out;
67 	sc->ilock_flags |= XFS_ILOCK_EXCL;
68 	xfs_ilock(sc->ip, XFS_ILOCK_EXCL);
69 
70 out:
71 	/* scrub teardown will unlock and release the inode for us */
72 	return error;
73 }
74 
75 /* Inode core */
76 
77 /* Validate di_extsize hint. */
78 STATIC void
79 xchk_inode_extsize(
80 	struct xfs_scrub	*sc,
81 	struct xfs_dinode	*dip,
82 	xfs_ino_t		ino,
83 	uint16_t		mode,
84 	uint16_t		flags)
85 {
86 	xfs_failaddr_t		fa;
87 
88 	fa = xfs_inode_validate_extsize(sc->mp, be32_to_cpu(dip->di_extsize),
89 			mode, flags);
90 	if (fa)
91 		xchk_ino_set_corrupt(sc, ino);
92 }
93 
94 /*
95  * Validate di_cowextsize hint.
96  *
97  * The rules are documented at xfs_ioctl_setattr_check_cowextsize().
98  * These functions must be kept in sync with each other.
99  */
100 STATIC void
101 xchk_inode_cowextsize(
102 	struct xfs_scrub	*sc,
103 	struct xfs_dinode	*dip,
104 	xfs_ino_t		ino,
105 	uint16_t		mode,
106 	uint16_t		flags,
107 	uint64_t		flags2)
108 {
109 	xfs_failaddr_t		fa;
110 
111 	fa = xfs_inode_validate_cowextsize(sc->mp,
112 			be32_to_cpu(dip->di_cowextsize), mode, flags,
113 			flags2);
114 	if (fa)
115 		xchk_ino_set_corrupt(sc, ino);
116 }
117 
118 /* Make sure the di_flags make sense for the inode. */
119 STATIC void
120 xchk_inode_flags(
121 	struct xfs_scrub	*sc,
122 	struct xfs_dinode	*dip,
123 	xfs_ino_t		ino,
124 	uint16_t		mode,
125 	uint16_t		flags)
126 {
127 	struct xfs_mount	*mp = sc->mp;
128 
129 	/* di_flags are all taken, last bit cannot be used */
130 	if (flags & ~XFS_DIFLAG_ANY)
131 		goto bad;
132 
133 	/* rt flags require rt device */
134 	if ((flags & (XFS_DIFLAG_REALTIME | XFS_DIFLAG_RTINHERIT)) &&
135 	    !mp->m_rtdev_targp)
136 		goto bad;
137 
138 	/* new rt bitmap flag only valid for rbmino */
139 	if ((flags & XFS_DIFLAG_NEWRTBM) && ino != mp->m_sb.sb_rbmino)
140 		goto bad;
141 
142 	/* directory-only flags */
143 	if ((flags & (XFS_DIFLAG_RTINHERIT |
144 		     XFS_DIFLAG_EXTSZINHERIT |
145 		     XFS_DIFLAG_PROJINHERIT |
146 		     XFS_DIFLAG_NOSYMLINKS)) &&
147 	    !S_ISDIR(mode))
148 		goto bad;
149 
150 	/* file-only flags */
151 	if ((flags & (XFS_DIFLAG_REALTIME | FS_XFLAG_EXTSIZE)) &&
152 	    !S_ISREG(mode))
153 		goto bad;
154 
155 	/* filestreams and rt make no sense */
156 	if ((flags & XFS_DIFLAG_FILESTREAM) && (flags & XFS_DIFLAG_REALTIME))
157 		goto bad;
158 
159 	return;
160 bad:
161 	xchk_ino_set_corrupt(sc, ino);
162 }
163 
164 /* Make sure the di_flags2 make sense for the inode. */
165 STATIC void
166 xchk_inode_flags2(
167 	struct xfs_scrub	*sc,
168 	struct xfs_dinode	*dip,
169 	xfs_ino_t		ino,
170 	uint16_t		mode,
171 	uint16_t		flags,
172 	uint64_t		flags2)
173 {
174 	struct xfs_mount	*mp = sc->mp;
175 
176 	/* Unknown di_flags2 could be from a future kernel */
177 	if (flags2 & ~XFS_DIFLAG2_ANY)
178 		xchk_ino_set_warning(sc, ino);
179 
180 	/* reflink flag requires reflink feature */
181 	if ((flags2 & XFS_DIFLAG2_REFLINK) &&
182 	    !xfs_sb_version_hasreflink(&mp->m_sb))
183 		goto bad;
184 
185 	/* cowextsize flag is checked w.r.t. mode separately */
186 
187 	/* file/dir-only flags */
188 	if ((flags2 & XFS_DIFLAG2_DAX) && !(S_ISREG(mode) || S_ISDIR(mode)))
189 		goto bad;
190 
191 	/* file-only flags */
192 	if ((flags2 & XFS_DIFLAG2_REFLINK) && !S_ISREG(mode))
193 		goto bad;
194 
195 	/* realtime and reflink make no sense, currently */
196 	if ((flags & XFS_DIFLAG_REALTIME) && (flags2 & XFS_DIFLAG2_REFLINK))
197 		goto bad;
198 
199 	/* dax and reflink make no sense, currently */
200 	if ((flags2 & XFS_DIFLAG2_DAX) && (flags2 & XFS_DIFLAG2_REFLINK))
201 		goto bad;
202 
203 	return;
204 bad:
205 	xchk_ino_set_corrupt(sc, ino);
206 }
207 
208 /* Scrub all the ondisk inode fields. */
209 STATIC void
210 xchk_dinode(
211 	struct xfs_scrub	*sc,
212 	struct xfs_dinode	*dip,
213 	xfs_ino_t		ino)
214 {
215 	struct xfs_mount	*mp = sc->mp;
216 	size_t			fork_recs;
217 	unsigned long long	isize;
218 	uint64_t		flags2;
219 	uint32_t		nextents;
220 	uint16_t		flags;
221 	uint16_t		mode;
222 
223 	flags = be16_to_cpu(dip->di_flags);
224 	if (dip->di_version >= 3)
225 		flags2 = be64_to_cpu(dip->di_flags2);
226 	else
227 		flags2 = 0;
228 
229 	/* di_mode */
230 	mode = be16_to_cpu(dip->di_mode);
231 	switch (mode & S_IFMT) {
232 	case S_IFLNK:
233 	case S_IFREG:
234 	case S_IFDIR:
235 	case S_IFCHR:
236 	case S_IFBLK:
237 	case S_IFIFO:
238 	case S_IFSOCK:
239 		/* mode is recognized */
240 		break;
241 	default:
242 		xchk_ino_set_corrupt(sc, ino);
243 		break;
244 	}
245 
246 	/* v1/v2 fields */
247 	switch (dip->di_version) {
248 	case 1:
249 		/*
250 		 * We autoconvert v1 inodes into v2 inodes on writeout,
251 		 * so just mark this inode for preening.
252 		 */
253 		xchk_ino_set_preen(sc, ino);
254 		break;
255 	case 2:
256 	case 3:
257 		if (dip->di_onlink != 0)
258 			xchk_ino_set_corrupt(sc, ino);
259 
260 		if (dip->di_mode == 0 && sc->ip)
261 			xchk_ino_set_corrupt(sc, ino);
262 
263 		if (dip->di_projid_hi != 0 &&
264 		    !xfs_sb_version_hasprojid32bit(&mp->m_sb))
265 			xchk_ino_set_corrupt(sc, ino);
266 		break;
267 	default:
268 		xchk_ino_set_corrupt(sc, ino);
269 		return;
270 	}
271 
272 	/*
273 	 * di_uid/di_gid -- -1 isn't invalid, but there's no way that
274 	 * userspace could have created that.
275 	 */
276 	if (dip->di_uid == cpu_to_be32(-1U) ||
277 	    dip->di_gid == cpu_to_be32(-1U))
278 		xchk_ino_set_warning(sc, ino);
279 
280 	/* di_format */
281 	switch (dip->di_format) {
282 	case XFS_DINODE_FMT_DEV:
283 		if (!S_ISCHR(mode) && !S_ISBLK(mode) &&
284 		    !S_ISFIFO(mode) && !S_ISSOCK(mode))
285 			xchk_ino_set_corrupt(sc, ino);
286 		break;
287 	case XFS_DINODE_FMT_LOCAL:
288 		if (!S_ISDIR(mode) && !S_ISLNK(mode))
289 			xchk_ino_set_corrupt(sc, ino);
290 		break;
291 	case XFS_DINODE_FMT_EXTENTS:
292 		if (!S_ISREG(mode) && !S_ISDIR(mode) && !S_ISLNK(mode))
293 			xchk_ino_set_corrupt(sc, ino);
294 		break;
295 	case XFS_DINODE_FMT_BTREE:
296 		if (!S_ISREG(mode) && !S_ISDIR(mode))
297 			xchk_ino_set_corrupt(sc, ino);
298 		break;
299 	case XFS_DINODE_FMT_UUID:
300 	default:
301 		xchk_ino_set_corrupt(sc, ino);
302 		break;
303 	}
304 
305 	/* di_[amc]time.nsec */
306 	if (be32_to_cpu(dip->di_atime.t_nsec) >= NSEC_PER_SEC)
307 		xchk_ino_set_corrupt(sc, ino);
308 	if (be32_to_cpu(dip->di_mtime.t_nsec) >= NSEC_PER_SEC)
309 		xchk_ino_set_corrupt(sc, ino);
310 	if (be32_to_cpu(dip->di_ctime.t_nsec) >= NSEC_PER_SEC)
311 		xchk_ino_set_corrupt(sc, ino);
312 
313 	/*
314 	 * di_size.  xfs_dinode_verify checks for things that screw up
315 	 * the VFS such as the upper bit being set and zero-length
316 	 * symlinks/directories, but we can do more here.
317 	 */
318 	isize = be64_to_cpu(dip->di_size);
319 	if (isize & (1ULL << 63))
320 		xchk_ino_set_corrupt(sc, ino);
321 
322 	/* Devices, fifos, and sockets must have zero size */
323 	if (!S_ISDIR(mode) && !S_ISREG(mode) && !S_ISLNK(mode) && isize != 0)
324 		xchk_ino_set_corrupt(sc, ino);
325 
326 	/* Directories can't be larger than the data section size (32G) */
327 	if (S_ISDIR(mode) && (isize == 0 || isize >= XFS_DIR2_SPACE_SIZE))
328 		xchk_ino_set_corrupt(sc, ino);
329 
330 	/* Symlinks can't be larger than SYMLINK_MAXLEN */
331 	if (S_ISLNK(mode) && (isize == 0 || isize >= XFS_SYMLINK_MAXLEN))
332 		xchk_ino_set_corrupt(sc, ino);
333 
334 	/*
335 	 * Warn if the running kernel can't handle the kinds of offsets
336 	 * needed to deal with the file size.  In other words, if the
337 	 * pagecache can't cache all the blocks in this file due to
338 	 * overly large offsets, flag the inode for admin review.
339 	 */
340 	if (isize >= mp->m_super->s_maxbytes)
341 		xchk_ino_set_warning(sc, ino);
342 
343 	/* di_nblocks */
344 	if (flags2 & XFS_DIFLAG2_REFLINK) {
345 		; /* nblocks can exceed dblocks */
346 	} else if (flags & XFS_DIFLAG_REALTIME) {
347 		/*
348 		 * nblocks is the sum of data extents (in the rtdev),
349 		 * attr extents (in the datadev), and both forks' bmbt
350 		 * blocks (in the datadev).  This clumsy check is the
351 		 * best we can do without cross-referencing with the
352 		 * inode forks.
353 		 */
354 		if (be64_to_cpu(dip->di_nblocks) >=
355 		    mp->m_sb.sb_dblocks + mp->m_sb.sb_rblocks)
356 			xchk_ino_set_corrupt(sc, ino);
357 	} else {
358 		if (be64_to_cpu(dip->di_nblocks) >= mp->m_sb.sb_dblocks)
359 			xchk_ino_set_corrupt(sc, ino);
360 	}
361 
362 	xchk_inode_flags(sc, dip, ino, mode, flags);
363 
364 	xchk_inode_extsize(sc, dip, ino, mode, flags);
365 
366 	/* di_nextents */
367 	nextents = be32_to_cpu(dip->di_nextents);
368 	fork_recs =  XFS_DFORK_DSIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
369 	switch (dip->di_format) {
370 	case XFS_DINODE_FMT_EXTENTS:
371 		if (nextents > fork_recs)
372 			xchk_ino_set_corrupt(sc, ino);
373 		break;
374 	case XFS_DINODE_FMT_BTREE:
375 		if (nextents <= fork_recs)
376 			xchk_ino_set_corrupt(sc, ino);
377 		break;
378 	default:
379 		if (nextents != 0)
380 			xchk_ino_set_corrupt(sc, ino);
381 		break;
382 	}
383 
384 	/* di_forkoff */
385 	if (XFS_DFORK_APTR(dip) >= (char *)dip + mp->m_sb.sb_inodesize)
386 		xchk_ino_set_corrupt(sc, ino);
387 	if (dip->di_anextents != 0 && dip->di_forkoff == 0)
388 		xchk_ino_set_corrupt(sc, ino);
389 	if (dip->di_forkoff == 0 && dip->di_aformat != XFS_DINODE_FMT_EXTENTS)
390 		xchk_ino_set_corrupt(sc, ino);
391 
392 	/* di_aformat */
393 	if (dip->di_aformat != XFS_DINODE_FMT_LOCAL &&
394 	    dip->di_aformat != XFS_DINODE_FMT_EXTENTS &&
395 	    dip->di_aformat != XFS_DINODE_FMT_BTREE)
396 		xchk_ino_set_corrupt(sc, ino);
397 
398 	/* di_anextents */
399 	nextents = be16_to_cpu(dip->di_anextents);
400 	fork_recs =  XFS_DFORK_ASIZE(dip, mp) / sizeof(struct xfs_bmbt_rec);
401 	switch (dip->di_aformat) {
402 	case XFS_DINODE_FMT_EXTENTS:
403 		if (nextents > fork_recs)
404 			xchk_ino_set_corrupt(sc, ino);
405 		break;
406 	case XFS_DINODE_FMT_BTREE:
407 		if (nextents <= fork_recs)
408 			xchk_ino_set_corrupt(sc, ino);
409 		break;
410 	default:
411 		if (nextents != 0)
412 			xchk_ino_set_corrupt(sc, ino);
413 	}
414 
415 	if (dip->di_version >= 3) {
416 		if (be32_to_cpu(dip->di_crtime.t_nsec) >= NSEC_PER_SEC)
417 			xchk_ino_set_corrupt(sc, ino);
418 		xchk_inode_flags2(sc, dip, ino, mode, flags, flags2);
419 		xchk_inode_cowextsize(sc, dip, ino, mode, flags,
420 				flags2);
421 	}
422 }
423 
424 /*
425  * Make sure the finobt doesn't think this inode is free.
426  * We don't have to check the inobt ourselves because we got the inode via
427  * IGET_UNTRUSTED, which checks the inobt for us.
428  */
429 static void
430 xchk_inode_xref_finobt(
431 	struct xfs_scrub		*sc,
432 	xfs_ino_t			ino)
433 {
434 	struct xfs_inobt_rec_incore	rec;
435 	xfs_agino_t			agino;
436 	int				has_record;
437 	int				error;
438 
439 	if (!sc->sa.fino_cur || xchk_skip_xref(sc->sm))
440 		return;
441 
442 	agino = XFS_INO_TO_AGINO(sc->mp, ino);
443 
444 	/*
445 	 * Try to get the finobt record.  If we can't get it, then we're
446 	 * in good shape.
447 	 */
448 	error = xfs_inobt_lookup(sc->sa.fino_cur, agino, XFS_LOOKUP_LE,
449 			&has_record);
450 	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
451 	    !has_record)
452 		return;
453 
454 	error = xfs_inobt_get_rec(sc->sa.fino_cur, &rec, &has_record);
455 	if (!xchk_should_check_xref(sc, &error, &sc->sa.fino_cur) ||
456 	    !has_record)
457 		return;
458 
459 	/*
460 	 * Otherwise, make sure this record either doesn't cover this inode,
461 	 * or that it does but it's marked present.
462 	 */
463 	if (rec.ir_startino > agino ||
464 	    rec.ir_startino + XFS_INODES_PER_CHUNK <= agino)
465 		return;
466 
467 	if (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino))
468 		xchk_btree_xref_set_corrupt(sc, sc->sa.fino_cur, 0);
469 }
470 
471 /* Cross reference the inode fields with the forks. */
472 STATIC void
473 xchk_inode_xref_bmap(
474 	struct xfs_scrub	*sc,
475 	struct xfs_dinode	*dip)
476 {
477 	xfs_extnum_t		nextents;
478 	xfs_filblks_t		count;
479 	xfs_filblks_t		acount;
480 	int			error;
481 
482 	if (xchk_skip_xref(sc->sm))
483 		return;
484 
485 	/* Walk all the extents to check nextents/naextents/nblocks. */
486 	error = xfs_bmap_count_blocks(sc->tp, sc->ip, XFS_DATA_FORK,
487 			&nextents, &count);
488 	if (!xchk_should_check_xref(sc, &error, NULL))
489 		return;
490 	if (nextents < be32_to_cpu(dip->di_nextents))
491 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
492 
493 	error = xfs_bmap_count_blocks(sc->tp, sc->ip, XFS_ATTR_FORK,
494 			&nextents, &acount);
495 	if (!xchk_should_check_xref(sc, &error, NULL))
496 		return;
497 	if (nextents != be16_to_cpu(dip->di_anextents))
498 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
499 
500 	/* Check nblocks against the inode. */
501 	if (count + acount != be64_to_cpu(dip->di_nblocks))
502 		xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
503 }
504 
505 /* Cross-reference with the other btrees. */
506 STATIC void
507 xchk_inode_xref(
508 	struct xfs_scrub	*sc,
509 	xfs_ino_t		ino,
510 	struct xfs_dinode	*dip)
511 {
512 	xfs_agnumber_t		agno;
513 	xfs_agblock_t		agbno;
514 	int			error;
515 
516 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
517 		return;
518 
519 	agno = XFS_INO_TO_AGNO(sc->mp, ino);
520 	agbno = XFS_INO_TO_AGBNO(sc->mp, ino);
521 
522 	error = xchk_ag_init(sc, agno, &sc->sa);
523 	if (!xchk_xref_process_error(sc, agno, agbno, &error))
524 		return;
525 
526 	xchk_xref_is_used_space(sc, agbno, 1);
527 	xchk_inode_xref_finobt(sc, ino);
528 	xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_INODES);
529 	xchk_xref_is_not_shared(sc, agbno, 1);
530 	xchk_inode_xref_bmap(sc, dip);
531 
532 	xchk_ag_free(sc, &sc->sa);
533 }
534 
535 /*
536  * If the reflink iflag disagrees with a scan for shared data fork extents,
537  * either flag an error (shared extents w/ no flag) or a preen (flag set w/o
538  * any shared extents).  We already checked for reflink iflag set on a non
539  * reflink filesystem.
540  */
541 static void
542 xchk_inode_check_reflink_iflag(
543 	struct xfs_scrub	*sc,
544 	xfs_ino_t		ino)
545 {
546 	struct xfs_mount	*mp = sc->mp;
547 	bool			has_shared;
548 	int			error;
549 
550 	if (!xfs_sb_version_hasreflink(&mp->m_sb))
551 		return;
552 
553 	error = xfs_reflink_inode_has_shared_extents(sc->tp, sc->ip,
554 			&has_shared);
555 	if (!xchk_xref_process_error(sc, XFS_INO_TO_AGNO(mp, ino),
556 			XFS_INO_TO_AGBNO(mp, ino), &error))
557 		return;
558 	if (xfs_is_reflink_inode(sc->ip) && !has_shared)
559 		xchk_ino_set_preen(sc, ino);
560 	else if (!xfs_is_reflink_inode(sc->ip) && has_shared)
561 		xchk_ino_set_corrupt(sc, ino);
562 }
563 
564 /* Scrub an inode. */
565 int
566 xchk_inode(
567 	struct xfs_scrub	*sc)
568 {
569 	struct xfs_dinode	di;
570 	int			error = 0;
571 
572 	/*
573 	 * If sc->ip is NULL, that means that the setup function called
574 	 * xfs_iget to look up the inode.  xfs_iget returned a EFSCORRUPTED
575 	 * and a NULL inode, so flag the corruption error and return.
576 	 */
577 	if (!sc->ip) {
578 		xchk_ino_set_corrupt(sc, sc->sm->sm_ino);
579 		return 0;
580 	}
581 
582 	/* Scrub the inode core. */
583 	xfs_inode_to_disk(sc->ip, &di, 0);
584 	xchk_dinode(sc, &di, sc->ip->i_ino);
585 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
586 		goto out;
587 
588 	/*
589 	 * Look for discrepancies between file's data blocks and the reflink
590 	 * iflag.  We already checked the iflag against the file mode when
591 	 * we scrubbed the dinode.
592 	 */
593 	if (S_ISREG(VFS_I(sc->ip)->i_mode))
594 		xchk_inode_check_reflink_iflag(sc, sc->ip->i_ino);
595 
596 	xchk_inode_xref(sc, sc->ip->i_ino, &di);
597 out:
598 	return error;
599 }
600