summaryrefslogtreecommitdiffstats
path: root/fs/xfs
diff options
context:
space:
mode:
authorDarrick J. Wong <darrick.wong@oracle.com>2017-11-02 15:58:36 -0700
committerDarrick J. Wong <darrick.wong@oracle.com>2017-11-09 19:27:32 -0800
commitd44b47fdd1c13f79a9b50a07576929f1c6c33c7f (patch)
tree3f35c3d80779536ba1109cccba016e470628826b /fs/xfs
parent65a7935ddc9a1f0c723842776259d76394b4bd11 (diff)
downloadlinux-d44b47fdd1c13f79a9b50a07576929f1c6c33c7f.tar.bz2
xfs: check the uniqueness of the AGFL entries
Make sure we don't list a block twice in the agfl by copying the contents of the AGFL to an array, sorting it, and looking for duplicates. We can easily check that the number of agfl entries we see actually matches the flcount, so do that too. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Dave Chinner <dchinner@redhat.com>
Diffstat (limited to 'fs/xfs')
-rw-r--r--fs/xfs/scrub/agheader.c63
1 files changed, 61 insertions, 2 deletions
diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 5495aa50002c..2a9b4f9e93c6 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -476,6 +476,12 @@ out:
/* AGFL */
+struct xfs_scrub_agfl_info {
+ unsigned int sz_entries;
+ unsigned int nr_entries;
+ xfs_agblock_t *entries;
+};
+
/* Scrub an AGFL block. */
STATIC int
xfs_scrub_agfl_block(
@@ -484,20 +490,39 @@ xfs_scrub_agfl_block(
void *priv)
{
struct xfs_mount *mp = sc->mp;
+ struct xfs_scrub_agfl_info *sai = priv;
xfs_agnumber_t agno = sc->sa.agno;
- if (!xfs_verify_agbno(mp, agno, agbno))
+ if (xfs_verify_agbno(mp, agno, agbno) &&
+ sai->nr_entries < sai->sz_entries)
+ sai->entries[sai->nr_entries++] = agbno;
+ else
xfs_scrub_block_set_corrupt(sc, sc->sa.agfl_bp);
return 0;
}
+static int
+xfs_scrub_agblock_cmp(
+ const void *pa,
+ const void *pb)
+{
+ const xfs_agblock_t *a = pa;
+ const xfs_agblock_t *b = pb;
+
+ return (int)*a - (int)*b;
+}
+
/* Scrub the AGFL. */
int
xfs_scrub_agfl(
struct xfs_scrub_context *sc)
{
+ struct xfs_scrub_agfl_info sai = { 0 };
+ struct xfs_agf *agf;
xfs_agnumber_t agno;
+ unsigned int agflcount;
+ unsigned int i;
int error;
agno = sc->sa.agno = sc->sm->sm_agno;
@@ -508,8 +533,42 @@ xfs_scrub_agfl(
if (!sc->sa.agf_bp)
return -EFSCORRUPTED;
+ /* Allocate buffer to ensure uniqueness of AGFL entries. */
+ agf = XFS_BUF_TO_AGF(sc->sa.agf_bp);
+ agflcount = be32_to_cpu(agf->agf_flcount);
+ if (agflcount > XFS_AGFL_SIZE(sc->mp)) {
+ xfs_scrub_block_set_corrupt(sc, sc->sa.agf_bp);
+ goto out;
+ }
+ sai.sz_entries = agflcount;
+ sai.entries = kmem_zalloc(sizeof(xfs_agblock_t) * agflcount, KM_NOFS);
+ if (!sai.entries) {
+ error = -ENOMEM;
+ goto out;
+ }
+
/* Check the blocks in the AGFL. */
- return xfs_scrub_walk_agfl(sc, xfs_scrub_agfl_block, NULL);
+ error = xfs_scrub_walk_agfl(sc, xfs_scrub_agfl_block, &sai);
+ if (error)
+ goto out_free;
+
+ if (agflcount != sai.nr_entries) {
+ xfs_scrub_block_set_corrupt(sc, sc->sa.agf_bp);
+ goto out_free;
+ }
+
+ /* Sort entries, check for duplicates. */
+ sort(sai.entries, sai.nr_entries, sizeof(sai.entries[0]),
+ xfs_scrub_agblock_cmp, NULL);
+ for (i = 1; i < sai.nr_entries; i++) {
+ if (sai.entries[i] == sai.entries[i - 1]) {
+ xfs_scrub_block_set_corrupt(sc, sc->sa.agf_bp);
+ break;
+ }
+ }
+
+out_free:
+ kmem_free(sai.entries);
out:
return error;
}