From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45010) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UyfJj-0000Iw-3d for qemu-devel@nongnu.org; Mon, 15 Jul 2013 05:43:43 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UyfJf-0002vE-Eo for qemu-devel@nongnu.org; Mon, 15 Jul 2013 05:43:39 -0400 Received: from mail-pd0-x230.google.com ([2607:f8b0:400e:c02::230]:41621) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UyfJe-0002ur-Tm for qemu-devel@nongnu.org; Mon, 15 Jul 2013 05:43:35 -0400 Received: by mail-pd0-f176.google.com with SMTP id t12so10542537pdi.35 for ; Mon, 15 Jul 2013 02:43:34 -0700 (PDT) From: Xu Wang Date: Mon, 15 Jul 2013 05:42:35 -0400 Message-Id: <1373881356-3294-7-git-send-email-cngesaint@gmail.com> In-Reply-To: <1373881356-3294-1-git-send-email-cngesaint@gmail.com> References: <1373881356-3294-1-git-send-email-cngesaint@gmail.com> Subject: [Qemu-devel] [PATCH V3 6/7] block: Add backing file loop check in qcow2_change_backing_file() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, famz@redhat.com, stefanha@gmail.com, wdongxu@linux.vnet.ibm.com, Xu Wang , xiawenc@linux.vnet.ibm.com Add backing file loop check before execute change backing file for qcow2 format. Signed-off-by: Xu Wang --- block/qcow2.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/qcow2.c b/block/qcow2.c index 0eceefe..01bd7d5 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1195,6 +1195,12 @@ fail: static int qcow2_change_backing_file(BlockDriverState *bs, const char *backing_file, const char *backing_fmt) { + /* Check if loop exists in backing files chain after changed */ + if (bdrv_backing_file_loop_check(bs->filename, + bs->drv ? bs->drv->format_name : NULL, + backing_file, backing_fmt)) { + return -EIO; + } pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); -- 1.8.1.4