qcow2: Fix qcow2_alloc_cluster_abort() for external data file

For external data file, cluster allocations return an offset in the data
file and are not refcounted. In this case, there is nothing to do for
qcow2_alloc_cluster_abort(). Freeing the same offset in the qcow2 file
is wrong and causes crashes in the better case or image corruption in
the worse case.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200211094900.17315-3-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2020-02-11 10:48:59 +01:00
parent dea9052ef1
commit c3b6658c1a

View file

@ -1026,8 +1026,11 @@ err:
void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m)
{
BDRVQcow2State *s = bs->opaque;
qcow2_free_clusters(bs, m->alloc_offset, m->nb_clusters << s->cluster_bits,
QCOW2_DISCARD_NEVER);
if (!has_data_file(bs)) {
qcow2_free_clusters(bs, m->alloc_offset,
m->nb_clusters << s->cluster_bits,
QCOW2_DISCARD_NEVER);
}
}
/*