fs/xfs/scrub/inode.c

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