From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50680) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WSmc9-0002FS-QD for qemu-devel@nongnu.org; Wed, 26 Mar 2014 08:07:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WSmc3-0004EQ-Rm for qemu-devel@nongnu.org; Wed, 26 Mar 2014 08:07:25 -0400 From: Stefan Hajnoczi Date: Wed, 26 Mar 2014 13:06:02 +0100 Message-Id: <1395835569-21193-41-git-send-email-stefanha@redhat.com> In-Reply-To: <1395835569-21193-1-git-send-email-stefanha@redhat.com> References: <1395835569-21193-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PATCH for-2.0 40/47] block: Limit request size (CVE-2014-0143) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , pmatouse@redhat.com, qemu-stable@nongnu.org From: Kevin Wolf Limiting the size of a single request to INT_MAX not only fixes a direct integer overflow in bdrv_check_request() (which would only trigger bad behaviour with ridiculously huge images, as in close to 2^64 bytes), but can also prevent overflows in all block drivers. Signed-off-by: Kevin Wolf --- block.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block.c b/block.c index acb70fd..7a90a1b 100644 --- a/block.c +++ b/block.c @@ -2588,6 +2588,10 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, int nb_sectors) { + if (nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) { + return -EIO; + } + return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE, nb_sectors * BDRV_SECTOR_SIZE); } -- 1.8.5.3