From patchwork Wed Dec 10 10:34:26 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 419575 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id EA3F21400DE for ; Wed, 10 Dec 2014 22:05:21 +1100 (AEDT) Received: from localhost ([::1]:44717 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xyf56-0001E8-1I for incoming@patchwork.ozlabs.org; Wed, 10 Dec 2014 06:05:20 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59416) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XyecU-0000qK-9c for qemu-devel@nongnu.org; Wed, 10 Dec 2014 05:35:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XyecO-0008Nd-Hv for qemu-devel@nongnu.org; Wed, 10 Dec 2014 05:35:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39606) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XyecO-0008NR-3S for qemu-devel@nongnu.org; Wed, 10 Dec 2014 05:35:40 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sBAAZdNB007466 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Wed, 10 Dec 2014 05:35:39 -0500 Received: from noname.str.redhat.com (dhcp-192-197.str.redhat.com [10.33.192.197]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sBAAYeSf016328; Wed, 10 Dec 2014 05:35:38 -0500 From: Kevin Wolf To: qemu-devel@nongnu.org Date: Wed, 10 Dec 2014 11:34:26 +0100 Message-Id: <1418207679-32260-61-git-send-email-kwolf@redhat.com> In-Reply-To: <1418207679-32260-1-git-send-email-kwolf@redhat.com> References: <1418207679-32260-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com Subject: [Qemu-devel] [PULL 60/73] qcow2: Prevent numerical overflow X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Max Reitz In qcow2_alloc_cluster_offset(), *num is limited to INT_MAX >> BDRV_SECTOR_BITS by all callers. However, since remaining is of type uint64_t, we might as well cast *num to that type before performing the shift. Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- block/qcow2-cluster.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index df0b2c9..1fea514 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1263,7 +1263,7 @@ int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, again: start = offset; - remaining = *num << BDRV_SECTOR_BITS; + remaining = (uint64_t)*num << BDRV_SECTOR_BITS; cluster_offset = 0; *host_offset = 0; cur_bytes = 0;