xfs: ignore leaf attr ichdr.count in verifier during log replay

commit 2e1d23370e upstream.

When we create a new attribute, we first create a shortform
attribute, and try to fit the new attribute into it.
If that fails, we copy the (empty) attribute into a leaf attribute,
and do the copy again.  Thus there can be a transient state where
we have an empty leaf attribute.

If we encounter this during log replay, the verifier will fail.
So add a test to ignore this part of the leaf attr verification
during log replay.

Thanks as usual to dchinner for spotting the problem.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eric Sandeen 2017-01-09 16:38:58 +01:00 committed by Greg Kroah-Hartman
parent c00203386d
commit 3c382dda47

View file

@ -253,6 +253,7 @@ xfs_attr3_leaf_verify(
{
struct xfs_mount *mp = bp->b_target->bt_mount;
struct xfs_attr_leafblock *leaf = bp->b_addr;
struct xfs_perag *pag = bp->b_pag;
struct xfs_attr3_icleaf_hdr ichdr;
xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
@ -273,7 +274,12 @@ xfs_attr3_leaf_verify(
if (ichdr.magic != XFS_ATTR_LEAF_MAGIC)
return false;
}
if (ichdr.count == 0)
/*
* In recovery there is a transient state where count == 0 is valid
* because we may have transitioned an empty shortform attr to a leaf
* if the attr didn't fit in shortform.
*/
if (pag && pag->pagf_init && ichdr.count == 0)
return false;
/* XXX: need to range check rest of attr header values */