From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56507) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YAe9o-0000fg-BL for qemu-devel@nongnu.org; Mon, 12 Jan 2015 07:31:45 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YAe9i-0002IC-7B for qemu-devel@nongnu.org; Mon, 12 Jan 2015 07:31:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45706) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YAe9h-0002I0-W6 for qemu-devel@nongnu.org; Mon, 12 Jan 2015 07:31:38 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t0CCVbNj030322 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Mon, 12 Jan 2015 07:31:37 -0500 From: Stefan Hajnoczi Date: Mon, 12 Jan 2015 12:31:32 +0000 Message-Id: <1421065893-18875-2-git-send-email-stefanha@redhat.com> In-Reply-To: <1421065893-18875-1-git-send-email-stefanha@redhat.com> References: <1421065893-18875-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PATCH 1/2] qed: check for header size overflow List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , mreitz@redhat.com Header size is denoted in clusters. The maximum cluster size is 64 MB but there is no limit on header size. Check for uint32_t overflow in case the header size field has a whacky value. Signed-off-by: Stefan Hajnoczi --- block/qed.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/qed.c b/block/qed.c index 80f18d8..d2c6045 100644 --- a/block/qed.c +++ b/block/qed.c @@ -440,6 +440,12 @@ static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags, s->l2_mask = s->table_nelems - 1; s->l1_shift = s->l2_shift + ffs(s->table_nelems) - 1; + /* Header size calculation must not overflow uint32_t */ + if ((uint64_t)s->header.cluster_size * s->header.header_size != + s->header.cluster_size * s->header.header_size) { + return -EINVAL; + } + if ((s->header.features & QED_F_BACKING_FILE)) { if ((uint64_t)s->header.backing_filename_offset + s->header.backing_filename_size > -- 2.1.0