From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
In xchk_iallocbt_rec, check the alignment of ir_startino by converting
the inode cluster block alignment into units of inodes instead of the
other way around (converting ir_startino to blocks). This prevents us
from tripping over off-by-one errors in ir_startino which are obscured
by the inode -> block conversion.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/scrub/ialloc.c | 56 ++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 50 insertions(+), 6 deletions(-)
diff --git a/fs/xfs/scrub/ialloc.c b/fs/xfs/scrub/ialloc.c
index fd431682db0b..1c6fef9b3799 100644
--- a/fs/xfs/scrub/ialloc.c
+++ b/fs/xfs/scrub/ialloc.c
@@ -265,6 +265,53 @@ xchk_iallocbt_check_freemask(
return error;
}
+/*
+ * Make sure this inode btree record is aligned properly. Because a fs block
+ * contains multiple inodes, we check that the inobt record is aligned to the
+ * correct inode, not just the correct block on disk. This results in a finer
+ * grained corruption check.
+ */
+STATIC void
+xchk_iallocbt_rec_alignment(
+ struct xchk_btree *bs,
+ struct xfs_inobt_rec_incore *irec)
+{
+ struct xfs_mount *mp = bs->sc->mp;
+
+ /*
+ * finobt records have different positioning requirements than inobt
+ * records: each finobt record must have a corresponding inobt record.
+ * That is checked in the xref function, so for now we only catch the
+ * obvious case where the record isn't at all aligned properly.
+ *
+ * Note that if a fs block contains more than a single chunk of inodes,
+ * we will have finobt records only for those chunks containing free
+ * inodes, and therefore expect chunk alignment of finobt records.
+ * Otherwise, we expect that the finobt record is aligned to the
+ * cluster alignment as told by the superblock.
+ */
+ if (bs->cur->bc_btnum == XFS_BTNUM_FINO) {
+ unsigned int imask;
+
+ imask = min_t(unsigned int, XFS_INODES_PER_CHUNK,
+ mp->m_cluster_align_inodes) - 1;
+ if (irec->ir_startino & imask)
+ xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+ return;
+ }
+
+ /* inobt records must be aligned to cluster and inoalignmnt size. */
+ if (irec->ir_startino & (mp->m_cluster_align_inodes - 1)) {
+ xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+ return;
+ }
+
+ if (irec->ir_startino & (mp->m_inodes_per_cluster - 1)) {
+ xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+ return;
+ }
+}
+
/* Scrub an inobt/finobt record. */
STATIC int
xchk_iallocbt_rec(
@@ -277,7 +324,6 @@ xchk_iallocbt_rec(
uint64_t holes;
xfs_agnumber_t agno = bs->cur->bc_private.a.agno;
xfs_agino_t agino;
- xfs_agblock_t agbno;
xfs_extlen_t len;
int holecount;
int i;
@@ -304,11 +350,9 @@ xchk_iallocbt_rec(
goto out;
}
- /* Make sure this record is aligned to cluster and inoalignmnt size. */
- agbno = XFS_AGINO_TO_AGBNO(mp, irec.ir_startino);
- if ((agbno & (mp->m_cluster_align - 1)) ||
- (agbno & (mp->m_blocks_per_cluster - 1)))
- xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+ xchk_iallocbt_rec_alignment(bs, &irec);
+ if (bs->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out;
iabt->inodes += irec.ir_count;
