From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56868) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e0Uyk-0001YE-TP for qemu-devel@nongnu.org; Fri, 06 Oct 2017 11:56:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e0Uyh-0004X8-0H for qemu-devel@nongnu.org; Fri, 06 Oct 2017 11:55:58 -0400 From: Kevin Wolf Date: Fri, 6 Oct 2017 17:54:22 +0200 Message-Id: <20171006155422.10135-55-kwolf@redhat.com> In-Reply-To: <20171006155422.10135-1-kwolf@redhat.com> References: <20171006155422.10135-1-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 54/54] block/mirror: check backing in bdrv_mirror_top_flush List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Vladimir Sementsov-Ogievskiy Backing may be zero after failed bdrv_append in mirror_start_job, which leads to SIGSEGV. Signed-off-by: Vladimir Sementsov-Ogievskiy Message-id: 20170929152255.5431-1-vsementsov@virtuozzo.com Signed-off-by: Max Reitz --- block/mirror.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block/mirror.c b/block/mirror.c index 3b6f0c5772..153758ca9f 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -1041,6 +1041,10 @@ 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); } -- 2.13.6