From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51693) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eyLBy-0000Kj-7b for qemu-devel@nongnu.org; Tue, 20 Mar 2018 13:36:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eyLBv-0000VM-Ix for qemu-devel@nongnu.org; Tue, 20 Mar 2018 13:36:58 -0400 From: Kevin Wolf Date: Tue, 20 Mar 2018 18:36:27 +0100 Message-Id: <20180320173632.25480-8-kwolf@redhat.com> In-Reply-To: <20180320173632.25480-1-kwolf@redhat.com> References: <20180320173632.25480-1-kwolf@redhat.com> Subject: [Qemu-devel] [PATCH for-2.12 07/12] parallels: Check maximum cluster size on create List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, mreitz@redhat.com, den@openvz.org, jcody@redhat.com, eblake@redhat.com, berrange@redhat.com, qemu-devel@nongnu.org It's unclear what the real maximum cluster size is for the Parallels format, but let's at least make sure that we don't get integer overflows in our .bdrv_co_create implementation. Signed-off-by: Kevin Wolf --- block/parallels.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/block/parallels.c b/block/parallels.c index 2da5e56a9d..e4ca018c2e 100644 --- a/block/parallels.c +++ b/block/parallels.c @@ -526,6 +526,11 @@ static int coroutine_fn parallels_co_create(BlockdevCreateOptions* opts, cl_size = DEFAULT_CLUSTER_SIZE; } + /* XXX What is the real limit here? This is an insanely large maximum. */ + if (cl_size >= UINT64_MAX / MAX_PARALLELS_IMAGE_FACTOR) { + error_setg(errp, "Cluster size is too large"); + return -EINVAL; + } if (total_size >= MAX_PARALLELS_IMAGE_FACTOR * cl_size) { error_setg(errp, "Image size is too large for this cluster size"); return -E2BIG; -- 2.13.6