From c050fdfeb575a57ba955427142469b2d2e5f7ac2 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 1 Feb 2019 09:08:50 -0800 Subject: xfs: check the ir_startino alignment directly 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 Reviewed-by: Brian Foster --- fs/xfs/scrub/ialloc.c | 56 +++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 50 insertions(+), 6 deletions(-) (limited to 'fs/xfs/scrub') 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; -- cgit v1.2.3