From: Kevin Wolf <kwolf@redhat.com>
Date: Wed, 18 Apr 2012 14:18:14 +0000 (+0200)
Subject: qcow2: Fix error handling in qcow2_alloc_cluster_offset
X-Git-Tag: TizenStudio_2.0_p2.3.2~208^2~4219^2~29
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8dc0a5e7a06c059683f9c379c0a4b0bbc20d5c74;p=sdk%2Femulator%2Fqemu.git

qcow2: Fix error handling in qcow2_alloc_cluster_offset

If do_alloc_cluster_offset() fails, the error handling code tried to
remove the request from the in-flight queue, to which it wasn't added
yet, resulting in a NULL pointer dereference.

m->nb_clusters really only becomes != 0 when the request is in the list.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---

diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index cbd224d..dcf70a2 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -931,7 +931,7 @@ again:
 fail:
     qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
 fail_put:
-    if (nb_clusters > 0) {
+    if (m->nb_clusters > 0) {
         QLIST_REMOVE(m, next_in_flight);
     }
     return ret;