From: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Backing may be zero after failed bdrv_append in mirror_start_job,
which leads to SIGSEGV.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Message-id: 20170929152255.5431-1-vsement...@virtuozzo.com
Signed-off-by: Max Reitz <mre...@redhat.com>
(cherry picked from commit ce960aa9062a407d0ca15aee3dcd3bd84a4e24f9)
Signed-off-by: Michael Roth <mdr...@linux.vnet.ibm.com>
---
block/mirror.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/block/mirror.c b/block/mirror.c
index 429751b9fe..03fc6d63b7 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -1056,6 +1056,10 @@ static int coroutine_fn
bdrv_mirror_top_pwritev(BlockDriverState *bs,
static int coroutine_fn bdrv_mirror_top_flush(BlockDriverState *bs)
{
+ if (bs->backing == NULL) {
+ /* we can be here after failed bdrv_append in mirror_start_job */
+ return 0;
+ }
return bdrv_co_flush(bs->backing->bs);
}
--
2.11.0
