xfs: sanitize sb_inopblock in xfs_mount_validate_sb

xfs_mount_validate_sb doesn't check sb_inopblock for sanity
(as does its xfs_repair counterpart, FWIW).

If it's out of bounds, we can go off the rails in i.e.
xfs_inode_buf_verify(), which uses sb_inopblock as a loop
limit when stepping through a metadata buffer.

The problem can be demonstrated easily by corrupting
sb_inopblock with xfs_db and trying to mount the result:

# mkfs.xfs -dfile,name=fsfile,size=1g
# xfs_db -x fsfile
xfs_db> sb 0
xfs_db> write inopblock 512
inopblock = 512
xfs_db> quit

# mount -o loop fsfile  mnt
and we blow up in xfs_inode_buf_verify().

With this patch, we get a (very noisy) corruption error,
and fail the mount as we should.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Eric Sandeen 2014-02-07 15:26:11 +11:00 committed by Dave Chinner
parent c6f9726444
commit 392c6de98a

View file

@ -288,6 +288,7 @@ xfs_mount_validate_sb(
sbp->sb_inodelog < XFS_DINODE_MIN_LOG ||
sbp->sb_inodelog > XFS_DINODE_MAX_LOG ||
sbp->sb_inodesize != (1 << sbp->sb_inodelog) ||
sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) ||
(sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) ||
(sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) ||
(sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) ||