diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/xfs/scrub/dir.c | 850 |
1 files changed, 850 insertions, 0 deletions
diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c new file mode 100644 index 000000000..33dfcba72 --- /dev/null +++ b/fs/xfs/scrub/dir.c @@ -0,0 +1,850 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2017 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <darrick.wong@oracle.com> + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_defer.h" +#include "xfs_btree.h" +#include "xfs_bit.h" +#include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_inode.h" +#include "xfs_icache.h" +#include "xfs_itable.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_dir2.h" +#include "xfs_dir2_priv.h" +#include "xfs_ialloc.h" +#include "scrub/xfs_scrub.h" +#include "scrub/scrub.h" +#include "scrub/common.h" +#include "scrub/trace.h" +#include "scrub/dabtree.h" + +/* Set us up to scrub directories. */ +int +xchk_setup_directory( + struct xfs_scrub *sc, + struct xfs_inode *ip) +{ + return xchk_setup_inode_contents(sc, ip, 0); +} + +/* Directories */ + +/* Scrub a directory entry. */ + +struct xchk_dir_ctx { + /* VFS fill-directory iterator */ + struct dir_context dir_iter; + + struct xfs_scrub *sc; +}; + +/* Check that an inode's mode matches a given DT_ type. */ +STATIC int +xchk_dir_check_ftype( + struct xchk_dir_ctx *sdc, + xfs_fileoff_t offset, + xfs_ino_t inum, + int dtype) +{ + struct xfs_mount *mp = sdc->sc->mp; + struct xfs_inode *ip; + int ino_dtype; + int error = 0; + + if (!xfs_sb_version_hasftype(&mp->m_sb)) { + if (dtype != DT_UNKNOWN && dtype != DT_DIR) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, + offset); + goto out; + } + + /* + * Grab the inode pointed to by the dirent. We release the + * inode before we cancel the scrub transaction. Since we're + * don't know a priori that releasing the inode won't trigger + * eofblocks cleanup (which allocates what would be a nested + * transaction), we can't use DONTCACHE here because DONTCACHE + * inodes can trigger immediate inactive cleanup of the inode. + */ + error = xfs_iget(mp, sdc->sc->tp, inum, 0, 0, &ip); + if (!xchk_fblock_xref_process_error(sdc->sc, XFS_DATA_FORK, offset, + &error)) + goto out; + + /* Convert mode to the DT_* values that dir_emit uses. */ + ino_dtype = xfs_dir3_get_dtype(mp, + xfs_mode_to_ftype(VFS_I(ip)->i_mode)); + if (ino_dtype != dtype) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset); + xfs_irele(ip); +out: + return error; +} + +/* + * Scrub a single directory entry. + * + * We use the VFS directory iterator (i.e. readdir) to call this + * function for every directory entry in a directory. Once we're here, + * we check the inode number to make sure it's sane, then we check that + * we can look up this filename. Finally, we check the ftype. + */ +STATIC int +xchk_dir_actor( + struct dir_context *dir_iter, + const char *name, + int namelen, + loff_t pos, + u64 ino, + unsigned type) +{ + struct xfs_mount *mp; + struct xfs_inode *ip; + struct xchk_dir_ctx *sdc; + struct xfs_name xname; + xfs_ino_t lookup_ino; + xfs_dablk_t offset; + int error = 0; + + sdc = container_of(dir_iter, struct xchk_dir_ctx, dir_iter); + ip = sdc->sc->ip; + mp = ip->i_mount; + offset = xfs_dir2_db_to_da(mp->m_dir_geo, + xfs_dir2_dataptr_to_db(mp->m_dir_geo, pos)); + + /* Does this inode number make sense? */ + if (!xfs_verify_dir_ino(mp, ino)) { + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset); + goto out; + } + + if (!strncmp(".", name, namelen)) { + /* If this is "." then check that the inum matches the dir. */ + if (xfs_sb_version_hasftype(&mp->m_sb) && type != DT_DIR) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, + offset); + if (ino != ip->i_ino) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, + offset); + } else if (!strncmp("..", name, namelen)) { + /* + * If this is ".." in the root inode, check that the inum + * matches this dir. + */ + if (xfs_sb_version_hasftype(&mp->m_sb) && type != DT_DIR) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, + offset); + if (ip->i_ino == mp->m_sb.sb_rootino && ino != ip->i_ino) + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, + offset); + } + + /* Verify that we can look up this name by hash. */ + xname.name = name; + xname.len = namelen; + xname.type = XFS_DIR3_FT_UNKNOWN; + + error = xfs_dir_lookup(sdc->sc->tp, ip, &xname, &lookup_ino, NULL); + /* ENOENT means the hash lookup failed and the dir is corrupt */ + if (error == -ENOENT) + error = -EFSCORRUPTED; + if (!xchk_fblock_process_error(sdc->sc, XFS_DATA_FORK, offset, + &error)) + goto out; + if (lookup_ino != ino) { + xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset); + goto out; + } + + /* Verify the file type. This function absorbs error codes. */ + error = xchk_dir_check_ftype(sdc, offset, lookup_ino, type); + if (error) + goto out; +out: + /* + * A negative error code returned here is supposed to cause the + * dir_emit caller (xfs_readdir) to abort the directory iteration + * and return zero to xchk_directory. + */ + if (error == 0 && sdc->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return -EFSCORRUPTED; + return error; +} + +/* Scrub a directory btree record. */ +STATIC int +xchk_dir_rec( + struct xchk_da_btree *ds, + int level, + void *rec) +{ + struct xfs_mount *mp = ds->state->mp; + struct xfs_dir2_leaf_entry *ent = rec; + struct xfs_inode *dp = ds->dargs.dp; + struct xfs_dir2_data_entry *dent; + struct xfs_buf *bp; + char *p, *endp; + xfs_ino_t ino; + xfs_dablk_t rec_bno; + xfs_dir2_db_t db; + xfs_dir2_data_aoff_t off; + xfs_dir2_dataptr_t ptr; + xfs_dahash_t calc_hash; + xfs_dahash_t hash; + unsigned int tag; + int error; + + /* Check the hash of the entry. */ + error = xchk_da_btree_hash(ds, level, &ent->hashval); + if (error) + goto out; + + /* Valid hash pointer? */ + ptr = be32_to_cpu(ent->address); + if (ptr == 0) + return 0; + + /* Find the directory entry's location. */ + db = xfs_dir2_dataptr_to_db(mp->m_dir_geo, ptr); + off = xfs_dir2_dataptr_to_off(mp->m_dir_geo, ptr); + rec_bno = xfs_dir2_db_to_da(mp->m_dir_geo, db); + + if (rec_bno >= mp->m_dir_geo->leafblk) { + xchk_da_set_corrupt(ds, level); + goto out; + } + error = xfs_dir3_data_read(ds->dargs.trans, dp, rec_bno, -2, &bp); + if (!xchk_fblock_process_error(ds->sc, XFS_DATA_FORK, rec_bno, + &error)) + goto out; + if (!bp) { + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + goto out; + } + xchk_buffer_recheck(ds->sc, bp); + + if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out_relse; + + dent = (struct xfs_dir2_data_entry *)(((char *)bp->b_addr) + off); + + /* Make sure we got a real directory entry. */ + p = (char *)mp->m_dir_inode_ops->data_entry_p(bp->b_addr); + endp = xfs_dir3_data_endp(mp->m_dir_geo, bp->b_addr); + if (!endp) { + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + goto out_relse; + } + while (p < endp) { + struct xfs_dir2_data_entry *dep; + struct xfs_dir2_data_unused *dup; + + dup = (struct xfs_dir2_data_unused *)p; + if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { + p += be16_to_cpu(dup->length); + continue; + } + dep = (struct xfs_dir2_data_entry *)p; + if (dep == dent) + break; + p += mp->m_dir_inode_ops->data_entsize(dep->namelen); + } + if (p >= endp) { + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + goto out_relse; + } + + /* Retrieve the entry, sanity check it, and compare hashes. */ + ino = be64_to_cpu(dent->inumber); + hash = be32_to_cpu(ent->hashval); + tag = be16_to_cpup(dp->d_ops->data_entry_tag_p(dent)); + if (!xfs_verify_dir_ino(mp, ino) || tag != off) + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + if (dent->namelen == 0) { + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + goto out_relse; + } + calc_hash = xfs_da_hashname(dent->name, dent->namelen); + if (calc_hash != hash) + xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno); + +out_relse: + xfs_trans_brelse(ds->dargs.trans, bp); +out: + return error; +} + +/* + * Is this unused entry either in the bestfree or smaller than all of + * them? We've already checked that the bestfrees are sorted longest to + * shortest, and that there aren't any bogus entries. + */ +STATIC void +xchk_directory_check_free_entry( + struct xfs_scrub *sc, + xfs_dablk_t lblk, + struct xfs_dir2_data_free *bf, + struct xfs_dir2_data_unused *dup) +{ + struct xfs_dir2_data_free *dfp; + unsigned int dup_length; + + dup_length = be16_to_cpu(dup->length); + + /* Unused entry is shorter than any of the bestfrees */ + if (dup_length < be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length)) + return; + + for (dfp = &bf[XFS_DIR2_DATA_FD_COUNT - 1]; dfp >= bf; dfp--) + if (dup_length == be16_to_cpu(dfp->length)) + return; + + /* Unused entry should be in the bestfrees but wasn't found. */ + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); +} + +/* Check free space info in a directory data block. */ +STATIC int +xchk_directory_data_bestfree( + struct xfs_scrub *sc, + xfs_dablk_t lblk, + bool is_block) +{ + struct xfs_dir2_data_unused *dup; + struct xfs_dir2_data_free *dfp; + struct xfs_buf *bp; + struct xfs_dir2_data_free *bf; + struct xfs_mount *mp = sc->mp; + const struct xfs_dir_ops *d_ops; + char *ptr; + char *endptr; + u16 tag; + unsigned int nr_bestfrees = 0; + unsigned int nr_frees = 0; + unsigned int smallest_bestfree; + int newlen; + int offset; + int error; + + d_ops = sc->ip->d_ops; + + if (is_block) { + /* dir block format */ + if (lblk != XFS_B_TO_FSBT(mp, XFS_DIR2_DATA_OFFSET)) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + error = xfs_dir3_block_read(sc->tp, sc->ip, &bp); + } else { + /* dir data format */ + error = xfs_dir3_data_read(sc->tp, sc->ip, lblk, -1, &bp); + } + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error)) + goto out; + xchk_buffer_recheck(sc, bp); + + /* XXX: Check xfs_dir3_data_hdr.pad is zero once we start setting it. */ + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out_buf; + + /* Do the bestfrees correspond to actual free space? */ + bf = d_ops->data_bestfree_p(bp->b_addr); + smallest_bestfree = UINT_MAX; + for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { + offset = be16_to_cpu(dfp->offset); + if (offset == 0) + continue; + if (offset >= mp->m_dir_geo->blksize) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out_buf; + } + dup = (struct xfs_dir2_data_unused *)(bp->b_addr + offset); + tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)); + + /* bestfree doesn't match the entry it points at? */ + if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG) || + be16_to_cpu(dup->length) != be16_to_cpu(dfp->length) || + tag != ((char *)dup - (char *)bp->b_addr)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out_buf; + } + + /* bestfree records should be ordered largest to smallest */ + if (smallest_bestfree < be16_to_cpu(dfp->length)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out_buf; + } + + smallest_bestfree = be16_to_cpu(dfp->length); + nr_bestfrees++; + } + + /* Make sure the bestfrees are actually the best free spaces. */ + ptr = (char *)d_ops->data_entry_p(bp->b_addr); + endptr = xfs_dir3_data_endp(mp->m_dir_geo, bp->b_addr); + + /* Iterate the entries, stopping when we hit or go past the end. */ + while (ptr < endptr) { + dup = (struct xfs_dir2_data_unused *)ptr; + /* Skip real entries */ + if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG)) { + struct xfs_dir2_data_entry *dep; + + dep = (struct xfs_dir2_data_entry *)ptr; + newlen = d_ops->data_entsize(dep->namelen); + if (newlen <= 0) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, + lblk); + goto out_buf; + } + ptr += newlen; + continue; + } + + /* Spot check this free entry */ + tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)); + if (tag != ((char *)dup - (char *)bp->b_addr)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out_buf; + } + + /* + * Either this entry is a bestfree or it's smaller than + * any of the bestfrees. + */ + xchk_directory_check_free_entry(sc, lblk, bf, dup); + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out_buf; + + /* Move on. */ + newlen = be16_to_cpu(dup->length); + if (newlen <= 0) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out_buf; + } + ptr += newlen; + if (ptr <= endptr) + nr_frees++; + } + + /* We're required to fill all the space. */ + if (ptr != endptr) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + + /* Did we see at least as many free slots as there are bestfrees? */ + if (nr_frees < nr_bestfrees) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); +out_buf: + xfs_trans_brelse(sc->tp, bp); +out: + return error; +} + +/* + * Does the free space length in the free space index block ($len) match + * the longest length in the directory data block's bestfree array? + * Assume that we've already checked that the data block's bestfree + * array is in order. + */ +STATIC void +xchk_directory_check_freesp( + struct xfs_scrub *sc, + xfs_dablk_t lblk, + struct xfs_buf *dbp, + unsigned int len) +{ + struct xfs_dir2_data_free *dfp; + + dfp = sc->ip->d_ops->data_bestfree_p(dbp->b_addr); + + if (len != be16_to_cpu(dfp->length)) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + + if (len > 0 && be16_to_cpu(dfp->offset) == 0) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); +} + +/* Check free space info in a directory leaf1 block. */ +STATIC int +xchk_directory_leaf1_bestfree( + struct xfs_scrub *sc, + struct xfs_da_args *args, + xfs_dablk_t lblk) +{ + struct xfs_dir3_icleaf_hdr leafhdr; + struct xfs_dir2_leaf_entry *ents; + struct xfs_dir2_leaf_tail *ltp; + struct xfs_dir2_leaf *leaf; + struct xfs_buf *dbp; + struct xfs_buf *bp; + const struct xfs_dir_ops *d_ops = sc->ip->d_ops; + struct xfs_da_geometry *geo = sc->mp->m_dir_geo; + __be16 *bestp; + __u16 best; + __u32 hash; + __u32 lasthash = 0; + __u32 bestcount; + unsigned int stale = 0; + int i; + int error; + + /* Read the free space block. */ + error = xfs_dir3_leaf_read(sc->tp, sc->ip, lblk, -1, &bp); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error)) + goto out; + xchk_buffer_recheck(sc, bp); + + leaf = bp->b_addr; + d_ops->leaf_hdr_from_disk(&leafhdr, leaf); + ents = d_ops->leaf_ents_p(leaf); + ltp = xfs_dir2_leaf_tail_p(geo, leaf); + bestcount = be32_to_cpu(ltp->bestcount); + bestp = xfs_dir2_leaf_bests_p(ltp); + + if (xfs_sb_version_hascrc(&sc->mp->m_sb)) { + struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr; + + if (hdr3->pad != cpu_to_be32(0)) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + } + + /* + * There should be as many bestfree slots as there are dir data + * blocks that can fit under i_size. + */ + if (bestcount != xfs_dir2_byte_to_db(geo, sc->ip->i_d.di_size)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + + /* Is the leaf count even remotely sane? */ + if (leafhdr.count > d_ops->leaf_max_ents(geo)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + + /* Leaves and bests don't overlap in leaf format. */ + if ((char *)&ents[leafhdr.count] > (char *)bestp) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + + /* Check hash value order, count stale entries. */ + for (i = 0; i < leafhdr.count; i++) { + hash = be32_to_cpu(ents[i].hashval); + if (i > 0 && lasthash > hash) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + lasthash = hash; + if (ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) + stale++; + } + if (leafhdr.stale != stale) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out; + + /* Check all the bestfree entries. */ + for (i = 0; i < bestcount; i++, bestp++) { + best = be16_to_cpu(*bestp); + if (best == NULLDATAOFF) + continue; + error = xfs_dir3_data_read(sc->tp, sc->ip, + i * args->geo->fsbcount, -1, &dbp); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, + &error)) + break; + xchk_directory_check_freesp(sc, lblk, dbp, best); + xfs_trans_brelse(sc->tp, dbp); + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out; + } +out: + return error; +} + +/* Check free space info in a directory freespace block. */ +STATIC int +xchk_directory_free_bestfree( + struct xfs_scrub *sc, + struct xfs_da_args *args, + xfs_dablk_t lblk) +{ + struct xfs_dir3_icfree_hdr freehdr; + struct xfs_buf *dbp; + struct xfs_buf *bp; + __be16 *bestp; + __u16 best; + unsigned int stale = 0; + int i; + int error; + + /* Read the free space block */ + error = xfs_dir2_free_read(sc->tp, sc->ip, lblk, &bp); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error)) + goto out; + xchk_buffer_recheck(sc, bp); + + if (xfs_sb_version_hascrc(&sc->mp->m_sb)) { + struct xfs_dir3_free_hdr *hdr3 = bp->b_addr; + + if (hdr3->pad != cpu_to_be32(0)) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + } + + /* Check all the entries. */ + sc->ip->d_ops->free_hdr_from_disk(&freehdr, bp->b_addr); + bestp = sc->ip->d_ops->free_bests_p(bp->b_addr); + for (i = 0; i < freehdr.nvalid; i++, bestp++) { + best = be16_to_cpu(*bestp); + if (best == NULLDATAOFF) { + stale++; + continue; + } + error = xfs_dir3_data_read(sc->tp, sc->ip, + (freehdr.firstdb + i) * args->geo->fsbcount, + -1, &dbp); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, + &error)) + break; + xchk_directory_check_freesp(sc, lblk, dbp, best); + xfs_trans_brelse(sc->tp, dbp); + } + + if (freehdr.nused + stale != freehdr.nvalid) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); +out: + return error; +} + +/* Check free space information in directories. */ +STATIC int +xchk_directory_blocks( + struct xfs_scrub *sc) +{ + struct xfs_bmbt_irec got; + struct xfs_da_args args; + struct xfs_ifork *ifp; + struct xfs_mount *mp = sc->mp; + xfs_fileoff_t leaf_lblk; + xfs_fileoff_t free_lblk; + xfs_fileoff_t lblk; + struct xfs_iext_cursor icur; + xfs_dablk_t dabno; + bool found; + int is_block = 0; + int error; + + /* Ignore local format directories. */ + if (sc->ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS && + sc->ip->i_d.di_format != XFS_DINODE_FMT_BTREE) + return 0; + + ifp = XFS_IFORK_PTR(sc->ip, XFS_DATA_FORK); + lblk = XFS_B_TO_FSB(mp, XFS_DIR2_DATA_OFFSET); + leaf_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_LEAF_OFFSET); + free_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_FREE_OFFSET); + + /* Is this a block dir? */ + args.dp = sc->ip; + args.geo = mp->m_dir_geo; + args.trans = sc->tp; + error = xfs_dir2_isblock(&args, &is_block); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error)) + goto out; + + /* Iterate all the data extents in the directory... */ + found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got); + while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) { + /* Block directories only have a single block at offset 0. */ + if (is_block && + (got.br_startoff > 0 || + got.br_blockcount != args.geo->fsbcount)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, + got.br_startoff); + break; + } + + /* No more data blocks... */ + if (got.br_startoff >= leaf_lblk) + break; + + /* + * Check each data block's bestfree data. + * + * Iterate all the fsbcount-aligned block offsets in + * this directory. The directory block reading code is + * smart enough to do its own bmap lookups to handle + * discontiguous directory blocks. When we're done + * with the extent record, re-query the bmap at the + * next fsbcount-aligned offset to avoid redundant + * block checks. + */ + for (lblk = roundup((xfs_dablk_t)got.br_startoff, + args.geo->fsbcount); + lblk < got.br_startoff + got.br_blockcount; + lblk += args.geo->fsbcount) { + error = xchk_directory_data_bestfree(sc, lblk, + is_block); + if (error) + goto out; + } + dabno = got.br_startoff + got.br_blockcount; + lblk = roundup(dabno, args.geo->fsbcount); + found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got); + } + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out; + + /* Look for a leaf1 block, which has free info. */ + if (xfs_iext_lookup_extent(sc->ip, ifp, leaf_lblk, &icur, &got) && + got.br_startoff == leaf_lblk && + got.br_blockcount == args.geo->fsbcount && + !xfs_iext_next_extent(ifp, &icur, &got)) { + if (is_block) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + error = xchk_directory_leaf1_bestfree(sc, &args, + leaf_lblk); + if (error) + goto out; + } + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + goto out; + + /* Scan for free blocks */ + lblk = free_lblk; + found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got); + while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) { + /* + * Dirs can't have blocks mapped above 2^32. + * Single-block dirs shouldn't even be here. + */ + lblk = got.br_startoff; + if (lblk & ~0xFFFFFFFFULL) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + if (is_block) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk); + goto out; + } + + /* + * Check each dir free block's bestfree data. + * + * Iterate all the fsbcount-aligned block offsets in + * this directory. The directory block reading code is + * smart enough to do its own bmap lookups to handle + * discontiguous directory blocks. When we're done + * with the extent record, re-query the bmap at the + * next fsbcount-aligned offset to avoid redundant + * block checks. + */ + for (lblk = roundup((xfs_dablk_t)got.br_startoff, + args.geo->fsbcount); + lblk < got.br_startoff + got.br_blockcount; + lblk += args.geo->fsbcount) { + error = xchk_directory_free_bestfree(sc, &args, + lblk); + if (error) + goto out; + } + dabno = got.br_startoff + got.br_blockcount; + lblk = roundup(dabno, args.geo->fsbcount); + found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got); + } +out: + return error; +} + +/* Scrub a whole directory. */ +int +xchk_directory( + struct xfs_scrub *sc) +{ + struct xchk_dir_ctx sdc = { + .dir_iter.actor = xchk_dir_actor, + .dir_iter.pos = 0, + .sc = sc, + }; + size_t bufsize; + loff_t oldpos; + int error = 0; + + if (!S_ISDIR(VFS_I(sc->ip)->i_mode)) + return -ENOENT; + + /* Plausible size? */ + if (sc->ip->i_d.di_size < xfs_dir2_sf_hdr_size(0)) { + xchk_ino_set_corrupt(sc, sc->ip->i_ino); + goto out; + } + + /* Check directory tree structure */ + error = xchk_da_btree(sc, XFS_DATA_FORK, xchk_dir_rec, NULL); + if (error) + return error; + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return error; + + /* Check the freespace. */ + error = xchk_directory_blocks(sc); + if (error) + return error; + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return error; + + /* + * Check that every dirent we see can also be looked up by hash. + * Userspace usually asks for a 32k buffer, so we will too. + */ + bufsize = (size_t)min_t(loff_t, XFS_READDIR_BUFSIZE, + sc->ip->i_d.di_size); + + /* + * Look up every name in this directory by hash. + * + * Use the xfs_readdir function to call xchk_dir_actor on + * every directory entry in this directory. In _actor, we check + * the name, inode number, and ftype (if applicable) of the + * entry. xfs_readdir uses the VFS filldir functions to provide + * iteration context. + * + * The VFS grabs a read or write lock via i_rwsem before it reads + * or writes to a directory. If we've gotten this far we've + * already obtained IOLOCK_EXCL, which (since 4.10) is the same as + * getting a write lock on i_rwsem. Therefore, it is safe for us + * to drop the ILOCK here in order to reuse the _readdir and + * _dir_lookup routines, which do their own ILOCK locking. + */ + oldpos = 0; + sc->ilock_flags &= ~XFS_ILOCK_EXCL; + xfs_iunlock(sc->ip, XFS_ILOCK_EXCL); + while (true) { + error = xfs_readdir(sc->tp, sc->ip, &sdc.dir_iter, bufsize); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, + &error)) + goto out; + if (oldpos == sdc.dir_iter.pos) + break; + oldpos = sdc.dir_iter.pos; + } + +out: + return error; +} |