fs/xfs/scrub/dir.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2017-2023 Oracle.  All Rights Reserved.
   4  * Author: Darrick J. Wong <[email protected]>
   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_log_format.h"
  13 #include "xfs_trans.h"
  14 #include "xfs_inode.h"
  15 #include "xfs_icache.h"
  16 #include "xfs_dir2.h"
  17 #include "xfs_dir2_priv.h"
  18 #include "scrub/scrub.h"
  19 #include "scrub/common.h"
  20 #include "scrub/dabtree.h"
  21 #include "scrub/readdir.h"
  22
  23 /* Set us up to scrub directories. */
  24 int
  25 xchk_setup_directory(
  26         struct xfs_scrub        *sc)
  27 {
  28         return xchk_setup_inode_contents(sc, 0);
  29 }
  30
  31 /* Directories */
  32
  33 /* Scrub a directory entry. */
  34
  35 /* Check that an inode's mode matches a given XFS_DIR3_FT_* type. */
  36 STATIC void
  37 xchk_dir_check_ftype(
  38         struct xfs_scrub        *sc,
  39         xfs_fileoff_t           offset,
  40         struct xfs_inode        *ip,
  41         int                     ftype)
  42 {
  43         struct xfs_mount        *mp = sc->mp;
  44
  45         if (!xfs_has_ftype(mp)) {
  46                 if (ftype != XFS_DIR3_FT_UNKNOWN && ftype != XFS_DIR3_FT_DIR)
  47                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
  48                 return;
  49         }
  50
  51         if (xfs_mode_to_ftype(VFS_I(ip)->i_mode) != ftype)
  52                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
  53 }
  54
  55 /*
  56  * Scrub a single directory entry.
  57  *
  58  * Check the inode number to make sure it's sane, then we check that we can
  59  * look up this filename.  Finally, we check the ftype.
  60  */
  61 STATIC int
  62 xchk_dir_actor(
  63         struct xfs_scrub        *sc,
  64         struct xfs_inode        *dp,
  65         xfs_dir2_dataptr_t      dapos,
  66         const struct xfs_name   *name,
  67         xfs_ino_t               ino,
  68         void                    *priv)
  69 {
  70         struct xfs_mount        *mp = dp->i_mount;
  71         struct xfs_inode        *ip;
  72         xfs_ino_t               lookup_ino;
  73         xfs_dablk_t             offset;
  74         int                     error = 0;
  75
  76         offset = xfs_dir2_db_to_da(mp->m_dir_geo,
  77                         xfs_dir2_dataptr_to_db(mp->m_dir_geo, dapos));
  78
  79         if (xchk_should_terminate(sc, &error))
  80                 return error;
  81
  82         /* Does this inode number make sense? */
  83         if (!xfs_verify_dir_ino(mp, ino)) {
  84                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
  85                 return -ECANCELED;
  86         }
  87
  88         /* Does this name make sense? */
  89         if (!xfs_dir2_namecheck(name->name, name->len)) {
  90                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
  91                 return -ECANCELED;
  92         }
  93
  94         if (!strncmp(".", name->name, name->len)) {
  95                 /* If this is "." then check that the inum matches the dir. */
  96                 if (ino != dp->i_ino)
  97                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
  98         } else if (!strncmp("..", name->name, name->len)) {
  99                 /*
 100                  * If this is ".." in the root inode, check that the inum
 101                  * matches this dir.
 102                  */
 103                 if (dp->i_ino == mp->m_sb.sb_rootino && ino != dp->i_ino)
 104                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
 105         }
 106
 107         /* Verify that we can look up this name by hash. */
 108         error = xchk_dir_lookup(sc, dp, name, &lookup_ino);
 109         /* ENOENT means the hash lookup failed and the dir is corrupt */
 110         if (error == -ENOENT)
 111                 error = -EFSCORRUPTED;
 112         if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, offset, &error))
 113                 goto out;
 114         if (lookup_ino != ino) {
 115                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
 116                 return -ECANCELED;
 117         }
 118
 119         /*
 120          * Grab the inode pointed to by the dirent.  We release the inode
 121          * before we cancel the scrub transaction.
 122          *
 123          * If _iget returns -EINVAL or -ENOENT then the child inode number is
 124          * garbage and the directory is corrupt.  If the _iget returns
 125          * -EFSCORRUPTED or -EFSBADCRC then the child is corrupt which is a
 126          *  cross referencing error.  Any other error is an operational error.
 127          */
 128         error = xchk_iget(sc, ino, &ip);
 129         if (error == -EINVAL || error == -ENOENT) {
 130                 error = -EFSCORRUPTED;
 131                 xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error);
 132                 goto out;
 133         }
 134         if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, offset, &error))
 135                 goto out;
 136
 137         xchk_dir_check_ftype(sc, offset, ip, name->type);
 138         xchk_irele(sc, ip);
 139 out:
 140         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 141                 return -ECANCELED;
 142         return error;
 143 }
 144
 145 /* Scrub a directory btree record. */
 146 STATIC int
 147 xchk_dir_rec(
 148         struct xchk_da_btree            *ds,
 149         int                             level)
 150 {
 151         struct xfs_name                 dname = { };
 152         struct xfs_da_state_blk         *blk = &ds->state->path.blk[level];
 153         struct xfs_mount                *mp = ds->state->mp;
 154         struct xfs_inode                *dp = ds->dargs.dp;
 155         struct xfs_da_geometry          *geo = mp->m_dir_geo;
 156         struct xfs_dir2_data_entry      *dent;
 157         struct xfs_buf                  *bp;
 158         struct xfs_dir2_leaf_entry      *ent;
 159         unsigned int                    end;
 160         unsigned int                    iter_off;
 161         xfs_ino_t                       ino;
 162         xfs_dablk_t                     rec_bno;
 163         xfs_dir2_db_t                   db;
 164         xfs_dir2_data_aoff_t            off;
 165         xfs_dir2_dataptr_t              ptr;
 166         xfs_dahash_t                    calc_hash;
 167         xfs_dahash_t                    hash;
 168         struct xfs_dir3_icleaf_hdr      hdr;
 169         unsigned int                    tag;
 170         int                             error;
 171
 172         ASSERT(blk->magic == XFS_DIR2_LEAF1_MAGIC ||
 173                blk->magic == XFS_DIR2_LEAFN_MAGIC);
 174
 175         xfs_dir2_leaf_hdr_from_disk(mp, &hdr, blk->bp->b_addr);
 176         ent = hdr.ents + blk->index;
 177
 178         /* Check the hash of the entry. */
 179         error = xchk_da_btree_hash(ds, level, &ent->hashval);
 180         if (error)
 181                 goto out;
 182
 183         /* Valid hash pointer? */
 184         ptr = be32_to_cpu(ent->address);
 185         if (ptr == 0)
 186                 return 0;
 187
 188         /* Find the directory entry's location. */
 189         db = xfs_dir2_dataptr_to_db(geo, ptr);
 190         off = xfs_dir2_dataptr_to_off(geo, ptr);
 191         rec_bno = xfs_dir2_db_to_da(geo, db);
 192
 193         if (rec_bno >= geo->leafblk) {
 194                 xchk_da_set_corrupt(ds, level);
 195                 goto out;
 196         }
 197         error = xfs_dir3_data_read(ds->dargs.trans, dp, rec_bno,
 198                         XFS_DABUF_MAP_HOLE_OK, &bp);
 199         if (!xchk_fblock_process_error(ds->sc, XFS_DATA_FORK, rec_bno,
 200                         &error))
 201                 goto out;
 202         if (!bp) {
 203                 xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 204                 goto out;
 205         }
 206         xchk_buffer_recheck(ds->sc, bp);
 207
 208         if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 209                 goto out_relse;
 210
 211         dent = bp->b_addr + off;
 212
 213         /* Make sure we got a real directory entry. */
 214         iter_off = geo->data_entry_offset;
 215         end = xfs_dir3_data_end_offset(geo, bp->b_addr);
 216         if (!end) {
 217                 xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 218                 goto out_relse;
 219         }
 220         for (;;) {
 221                 struct xfs_dir2_data_entry      *dep = bp->b_addr + iter_off;
 222                 struct xfs_dir2_data_unused     *dup = bp->b_addr + iter_off;
 223
 224                 if (iter_off >= end) {
 225                         xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 226                         goto out_relse;
 227                 }
 228
 229                 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
 230                         iter_off += be16_to_cpu(dup->length);
 231                         continue;
 232                 }
 233                 if (dep == dent)
 234                         break;
 235                 iter_off += xfs_dir2_data_entsize(mp, dep->namelen);
 236         }
 237
 238         /* Retrieve the entry, sanity check it, and compare hashes. */
 239         ino = be64_to_cpu(dent->inumber);
 240         hash = be32_to_cpu(ent->hashval);
 241         tag = be16_to_cpup(xfs_dir2_data_entry_tag_p(mp, dent));
 242         if (!xfs_verify_dir_ino(mp, ino) || tag != off)
 243                 xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 244         if (dent->namelen == 0) {
 245                 xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 246                 goto out_relse;
 247         }
 248
 249         /* Does the directory hash match? */
 250         dname.name = dent->name;
 251         dname.len = dent->namelen;
 252         calc_hash = xfs_dir2_hashname(mp, &dname);
 253         if (calc_hash != hash)
 254                 xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
 255
 256 out_relse:
 257         xfs_trans_brelse(ds->dargs.trans, bp);
 258 out:
 259         return error;
 260 }
 261
 262 /*
 263  * Is this unused entry either in the bestfree or smaller than all of
 264  * them?  We've already checked that the bestfrees are sorted longest to
 265  * shortest, and that there aren't any bogus entries.
 266  */
 267 STATIC void
 268 xchk_directory_check_free_entry(
 269         struct xfs_scrub                *sc,
 270         xfs_dablk_t                     lblk,
 271         struct xfs_dir2_data_free       *bf,
 272         struct xfs_dir2_data_unused     *dup)
 273 {
 274         struct xfs_dir2_data_free       *dfp;
 275         unsigned int                    dup_length;
 276
 277         dup_length = be16_to_cpu(dup->length);
 278
 279         /* Unused entry is shorter than any of the bestfrees */
 280         if (dup_length < be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length))
 281                 return;
 282
 283         for (dfp = &bf[XFS_DIR2_DATA_FD_COUNT - 1]; dfp >= bf; dfp--)
 284                 if (dup_length == be16_to_cpu(dfp->length))
 285                         return;
 286
 287         /* Unused entry should be in the bestfrees but wasn't found. */
 288         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 289 }
 290
 291 /* Check free space info in a directory data block. */
 292 STATIC int
 293 xchk_directory_data_bestfree(
 294         struct xfs_scrub                *sc,
 295         xfs_dablk_t                     lblk,
 296         bool                            is_block)
 297 {
 298         struct xfs_dir2_data_unused     *dup;
 299         struct xfs_dir2_data_free       *dfp;
 300         struct xfs_buf                  *bp;
 301         struct xfs_dir2_data_free       *bf;
 302         struct xfs_mount                *mp = sc->mp;
 303         u16                             tag;
 304         unsigned int                    nr_bestfrees = 0;
 305         unsigned int                    nr_frees = 0;
 306         unsigned int                    smallest_bestfree;
 307         int                             newlen;
 308         unsigned int                    offset;
 309         unsigned int                    end;
 310         int                             error;
 311
 312         if (is_block) {
 313                 /* dir block format */
 314                 if (lblk != XFS_B_TO_FSBT(mp, XFS_DIR2_DATA_OFFSET))
 315                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 316                 error = xfs_dir3_block_read(sc->tp, sc->ip, &bp);
 317         } else {
 318                 /* dir data format */
 319                 error = xfs_dir3_data_read(sc->tp, sc->ip, lblk, 0, &bp);
 320         }
 321         if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 322                 goto out;
 323         xchk_buffer_recheck(sc, bp);
 324
 325         /* XXX: Check xfs_dir3_data_hdr.pad is zero once we start setting it. */
 326
 327         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 328                 goto out_buf;
 329
 330         /* Do the bestfrees correspond to actual free space? */
 331         bf = xfs_dir2_data_bestfree_p(mp, bp->b_addr);
 332         smallest_bestfree = UINT_MAX;
 333         for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
 334                 offset = be16_to_cpu(dfp->offset);
 335                 if (offset == 0)
 336                         continue;
 337                 if (offset >= mp->m_dir_geo->blksize) {
 338                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 339                         goto out_buf;
 340                 }
 341                 dup = bp->b_addr + offset;
 342                 tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup));
 343
 344                 /* bestfree doesn't match the entry it points at? */
 345                 if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG) ||
 346                     be16_to_cpu(dup->length) != be16_to_cpu(dfp->length) ||
 347                     tag != offset) {
 348                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 349                         goto out_buf;
 350                 }
 351
 352                 /* bestfree records should be ordered largest to smallest */
 353                 if (smallest_bestfree < be16_to_cpu(dfp->length)) {
 354                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 355                         goto out_buf;
 356                 }
 357
 358                 smallest_bestfree = be16_to_cpu(dfp->length);
 359                 nr_bestfrees++;
 360         }
 361
 362         /* Make sure the bestfrees are actually the best free spaces. */
 363         offset = mp->m_dir_geo->data_entry_offset;
 364         end = xfs_dir3_data_end_offset(mp->m_dir_geo, bp->b_addr);
 365
 366         /* Iterate the entries, stopping when we hit or go past the end. */
 367         while (offset < end) {
 368                 dup = bp->b_addr + offset;
 369
 370                 /* Skip real entries */
 371                 if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG)) {
 372                         struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
 373
 374                         newlen = xfs_dir2_data_entsize(mp, dep->namelen);
 375                         if (newlen <= 0) {
 376                                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK,
 377                                                 lblk);
 378                                 goto out_buf;
 379                         }
 380                         offset += newlen;
 381                         continue;
 382                 }
 383
 384                 /* Spot check this free entry */
 385                 tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup));
 386                 if (tag != offset) {
 387                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 388                         goto out_buf;
 389                 }
 390
 391                 /*
 392                  * Either this entry is a bestfree or it's smaller than
 393                  * any of the bestfrees.
 394                  */
 395                 xchk_directory_check_free_entry(sc, lblk, bf, dup);
 396                 if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 397                         goto out_buf;
 398
 399                 /* Move on. */
 400                 newlen = be16_to_cpu(dup->length);
 401                 if (newlen <= 0) {
 402                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 403                         goto out_buf;
 404                 }
 405                 offset += newlen;
 406                 if (offset <= end)
 407                         nr_frees++;
 408         }
 409
 410         /* We're required to fill all the space. */
 411         if (offset != end)
 412                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 413
 414         /* Did we see at least as many free slots as there are bestfrees? */
 415         if (nr_frees < nr_bestfrees)
 416                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 417 out_buf:
 418         xfs_trans_brelse(sc->tp, bp);
 419 out:
 420         return error;
 421 }
 422
 423 /*
 424  * Does the free space length in the free space index block ($len) match
 425  * the longest length in the directory data block's bestfree array?
 426  * Assume that we've already checked that the data block's bestfree
 427  * array is in order.
 428  */
 429 STATIC void
 430 xchk_directory_check_freesp(
 431         struct xfs_scrub                *sc,
 432         xfs_dablk_t                     lblk,
 433         struct xfs_buf                  *dbp,
 434         unsigned int                    len)
 435 {
 436         struct xfs_dir2_data_free       *dfp;
 437
 438         dfp = xfs_dir2_data_bestfree_p(sc->mp, dbp->b_addr);
 439
 440         if (len != be16_to_cpu(dfp->length))
 441                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 442
 443         if (len > 0 && be16_to_cpu(dfp->offset) == 0)
 444                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 445 }
 446
 447 /* Check free space info in a directory leaf1 block. */
 448 STATIC int
 449 xchk_directory_leaf1_bestfree(
 450         struct xfs_scrub                *sc,
 451         struct xfs_da_args              *args,
 452         xfs_dir2_db_t                   last_data_db,
 453         xfs_dablk_t                     lblk)
 454 {
 455         struct xfs_dir3_icleaf_hdr      leafhdr;
 456         struct xfs_dir2_leaf_tail       *ltp;
 457         struct xfs_dir2_leaf            *leaf;
 458         struct xfs_buf                  *dbp;
 459         struct xfs_buf                  *bp;
 460         struct xfs_da_geometry          *geo = sc->mp->m_dir_geo;
 461         __be16                          *bestp;
 462         __u16                           best;
 463         __u32                           hash;
 464         __u32                           lasthash = 0;
 465         __u32                           bestcount;
 466         unsigned int                    stale = 0;
 467         int                             i;
 468         int                             error;
 469
 470         /* Read the free space block. */
 471         error = xfs_dir3_leaf_read(sc->tp, sc->ip, lblk, &bp);
 472         if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 473                 return error;
 474         xchk_buffer_recheck(sc, bp);
 475
 476         leaf = bp->b_addr;
 477         xfs_dir2_leaf_hdr_from_disk(sc->ip->i_mount, &leafhdr, leaf);
 478         ltp = xfs_dir2_leaf_tail_p(geo, leaf);
 479         bestcount = be32_to_cpu(ltp->bestcount);
 480         bestp = xfs_dir2_leaf_bests_p(ltp);
 481
 482         if (xfs_has_crc(sc->mp)) {
 483                 struct xfs_dir3_leaf_hdr        *hdr3 = bp->b_addr;
 484
 485                 if (hdr3->pad != cpu_to_be32(0))
 486                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 487         }
 488
 489         /*
 490          * There must be enough bestfree slots to cover all the directory data
 491          * blocks that we scanned.  It is possible for there to be a hole
 492          * between the last data block and i_disk_size.  This seems like an
 493          * oversight to the scrub author, but as we have been writing out
 494          * directories like this (and xfs_repair doesn't mind them) for years,
 495          * that's what we have to check.
 496          */
 497         if (bestcount != last_data_db + 1) {
 498                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 499                 goto out;
 500         }
 501
 502         /* Is the leaf count even remotely sane? */
 503         if (leafhdr.count > geo->leaf_max_ents) {
 504                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 505                 goto out;
 506         }
 507
 508         /* Leaves and bests don't overlap in leaf format. */
 509         if ((char *)&leafhdr.ents[leafhdr.count] > (char *)bestp) {
 510                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 511                 goto out;
 512         }
 513
 514         /* Check hash value order, count stale entries.  */
 515         for (i = 0; i < leafhdr.count; i++) {
 516                 hash = be32_to_cpu(leafhdr.ents[i].hashval);
 517                 if (i > 0 && lasthash > hash)
 518                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 519                 lasthash = hash;
 520                 if (leafhdr.ents[i].address ==
 521                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
 522                         stale++;
 523         }
 524         if (leafhdr.stale != stale)
 525                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 526         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 527                 goto out;
 528
 529         /* Check all the bestfree entries. */
 530         for (i = 0; i < bestcount; i++, bestp++) {
 531                 best = be16_to_cpu(*bestp);
 532                 error = xfs_dir3_data_read(sc->tp, sc->ip,
 533                                 xfs_dir2_db_to_da(args->geo, i),
 534                                 XFS_DABUF_MAP_HOLE_OK,
 535                                 &dbp);
 536                 if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
 537                                 &error))
 538                         break;
 539
 540                 if (!dbp) {
 541                         if (best != NULLDATAOFF) {
 542                                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK,
 543                                                 lblk);
 544                                 break;
 545                         }
 546                         continue;
 547                 }
 548
 549                 if (best == NULLDATAOFF)
 550                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 551                 else
 552                         xchk_directory_check_freesp(sc, lblk, dbp, best);
 553                 xfs_trans_brelse(sc->tp, dbp);
 554                 if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 555                         break;
 556         }
 557 out:
 558         xfs_trans_brelse(sc->tp, bp);
 559         return error;
 560 }
 561
 562 /* Check free space info in a directory freespace block. */
 563 STATIC int
 564 xchk_directory_free_bestfree(
 565         struct xfs_scrub                *sc,
 566         struct xfs_da_args              *args,
 567         xfs_dablk_t                     lblk)
 568 {
 569         struct xfs_dir3_icfree_hdr      freehdr;
 570         struct xfs_buf                  *dbp;
 571         struct xfs_buf                  *bp;
 572         __u16                           best;
 573         unsigned int                    stale = 0;
 574         int                             i;
 575         int                             error;
 576
 577         /* Read the free space block */
 578         error = xfs_dir2_free_read(sc->tp, sc->ip, lblk, &bp);
 579         if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 580                 return error;
 581         xchk_buffer_recheck(sc, bp);
 582
 583         if (xfs_has_crc(sc->mp)) {
 584                 struct xfs_dir3_free_hdr        *hdr3 = bp->b_addr;
 585
 586                 if (hdr3->pad != cpu_to_be32(0))
 587                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 588         }
 589
 590         /* Check all the entries. */
 591         xfs_dir2_free_hdr_from_disk(sc->ip->i_mount, &freehdr, bp->b_addr);
 592         for (i = 0; i < freehdr.nvalid; i++) {
 593                 best = be16_to_cpu(freehdr.bests[i]);
 594                 if (best == NULLDATAOFF) {
 595                         stale++;
 596                         continue;
 597                 }
 598                 error = xfs_dir3_data_read(sc->tp, sc->ip,
 599                                 (freehdr.firstdb + i) * args->geo->fsbcount,
 600                                 0, &dbp);
 601                 if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
 602                                 &error))
 603                         goto out;
 604                 xchk_directory_check_freesp(sc, lblk, dbp, best);
 605                 xfs_trans_brelse(sc->tp, dbp);
 606         }
 607
 608         if (freehdr.nused + stale != freehdr.nvalid)
 609                 xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 610 out:
 611         xfs_trans_brelse(sc->tp, bp);
 612         return error;
 613 }
 614
 615 /* Check free space information in directories. */
 616 STATIC int
 617 xchk_directory_blocks(
 618         struct xfs_scrub        *sc)
 619 {
 620         struct xfs_bmbt_irec    got;
 621         struct xfs_da_args      args = {
 622                 .dp             = sc ->ip,
 623                 .whichfork      = XFS_DATA_FORK,
 624                 .geo            = sc->mp->m_dir_geo,
 625                 .trans          = sc->tp,
 626         };
 627         struct xfs_ifork        *ifp = xfs_ifork_ptr(sc->ip, XFS_DATA_FORK);
 628         struct xfs_mount        *mp = sc->mp;
 629         xfs_fileoff_t           leaf_lblk;
 630         xfs_fileoff_t           free_lblk;
 631         xfs_fileoff_t           lblk;
 632         struct xfs_iext_cursor  icur;
 633         xfs_dablk_t             dabno;
 634         xfs_dir2_db_t           last_data_db = 0;
 635         bool                    found;
 636         bool                    is_block = false;
 637         int                     error;
 638
 639         /* Ignore local format directories. */
 640         if (ifp->if_format != XFS_DINODE_FMT_EXTENTS &&
 641             ifp->if_format != XFS_DINODE_FMT_BTREE)
 642                 return 0;
 643
 644         lblk = XFS_B_TO_FSB(mp, XFS_DIR2_DATA_OFFSET);
 645         leaf_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_LEAF_OFFSET);
 646         free_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_FREE_OFFSET);
 647
 648         /* Is this a block dir? */
 649         error = xfs_dir2_isblock(&args, &is_block);
 650         if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 651                 goto out;
 652
 653         /* Iterate all the data extents in the directory... */
 654         found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
 655         while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
 656                 /* No more data blocks... */
 657                 if (got.br_startoff >= leaf_lblk)
 658                         break;
 659
 660                 /*
 661                  * Check each data block's bestfree data.
 662                  *
 663                  * Iterate all the fsbcount-aligned block offsets in
 664                  * this directory.  The directory block reading code is
 665                  * smart enough to do its own bmap lookups to handle
 666                  * discontiguous directory blocks.  When we're done
 667                  * with the extent record, re-query the bmap at the
 668                  * next fsbcount-aligned offset to avoid redundant
 669                  * block checks.
 670                  */
 671                 for (lblk = roundup((xfs_dablk_t)got.br_startoff,
 672                                 args.geo->fsbcount);
 673                      lblk < got.br_startoff + got.br_blockcount;
 674                      lblk += args.geo->fsbcount) {
 675                         last_data_db = xfs_dir2_da_to_db(args.geo, lblk);
 676                         error = xchk_directory_data_bestfree(sc, lblk,
 677                                         is_block);
 678                         if (error)
 679                                 goto out;
 680                 }
 681                 dabno = got.br_startoff + got.br_blockcount;
 682                 lblk = roundup(dabno, args.geo->fsbcount);
 683                 found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
 684         }
 685
 686         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 687                 goto out;
 688
 689         /* Look for a leaf1 block, which has free info. */
 690         if (xfs_iext_lookup_extent(sc->ip, ifp, leaf_lblk, &icur, &got) &&
 691             got.br_startoff == leaf_lblk &&
 692             got.br_blockcount == args.geo->fsbcount &&
 693             !xfs_iext_next_extent(ifp, &icur, &got)) {
 694                 if (is_block) {
 695                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 696                         goto out;
 697                 }
 698                 error = xchk_directory_leaf1_bestfree(sc, &args, last_data_db,
 699                                 leaf_lblk);
 700                 if (error)
 701                         goto out;
 702         }
 703
 704         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 705                 goto out;
 706
 707         /* Scan for free blocks */
 708         lblk = free_lblk;
 709         found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
 710         while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
 711                 /*
 712                  * Dirs can't have blocks mapped above 2^32.
 713                  * Single-block dirs shouldn't even be here.
 714                  */
 715                 lblk = got.br_startoff;
 716                 if (lblk & ~0xFFFFFFFFULL) {
 717                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 718                         goto out;
 719                 }
 720                 if (is_block) {
 721                         xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
 722                         goto out;
 723                 }
 724
 725                 /*
 726                  * Check each dir free block's bestfree data.
 727                  *
 728                  * Iterate all the fsbcount-aligned block offsets in
 729                  * this directory.  The directory block reading code is
 730                  * smart enough to do its own bmap lookups to handle
 731                  * discontiguous directory blocks.  When we're done
 732                  * with the extent record, re-query the bmap at the
 733                  * next fsbcount-aligned offset to avoid redundant
 734                  * block checks.
 735                  */
 736                 for (lblk = roundup((xfs_dablk_t)got.br_startoff,
 737                                 args.geo->fsbcount);
 738                      lblk < got.br_startoff + got.br_blockcount;
 739                      lblk += args.geo->fsbcount) {
 740                         error = xchk_directory_free_bestfree(sc, &args,
 741                                         lblk);
 742                         if (error)
 743                                 goto out;
 744                 }
 745                 dabno = got.br_startoff + got.br_blockcount;
 746                 lblk = roundup(dabno, args.geo->fsbcount);
 747                 found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
 748         }
 749 out:
 750         return error;
 751 }
 752
 753 /* Scrub a whole directory. */
 754 int
 755 xchk_directory(
 756         struct xfs_scrub        *sc)
 757 {
 758         int                     error;
 759
 760         if (!S_ISDIR(VFS_I(sc->ip)->i_mode))
 761                 return -ENOENT;
 762
 763         /* Plausible size? */
 764         if (sc->ip->i_disk_size < xfs_dir2_sf_hdr_size(0)) {
 765                 xchk_ino_set_corrupt(sc, sc->ip->i_ino);
 766                 return 0;
 767         }
 768
 769         /* Check directory tree structure */
 770         error = xchk_da_btree(sc, XFS_DATA_FORK, xchk_dir_rec, NULL);
 771         if (error)
 772                 return error;
 773
 774         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 775                 return 0;
 776
 777         /* Check the freespace. */
 778         error = xchk_directory_blocks(sc);
 779         if (error)
 780                 return error;
 781
 782         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
 783                 return 0;
 784
 785         /* Look up every name in this directory by hash. */
 786         error = xchk_dir_walk(sc, sc->ip, xchk_dir_actor, NULL);
 787         if (error == -ECANCELED)
 788                 error = 0;
 789         return error;
 790 }