From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59193) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yt4au-0005bl-8c for qemu-devel@nongnu.org; Thu, 14 May 2015 21:39:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yt4at-0005Hv-Ie for qemu-devel@nongnu.org; Thu, 14 May 2015 21:39:20 -0400 From: Fam Zheng Date: Fri, 15 May 2015 09:39:10 +0800 Message-Id: <1431653951-28178-2-git-send-email-famz@redhat.com> In-Reply-To: <1431653951-28178-1-git-send-email-famz@redhat.com> References: <1431653951-28178-1-git-send-email-famz@redhat.com> Subject: [Qemu-devel] [PATCH 1/2] block: Detect multiplication overflow in bdrv_getlength List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , qemu-block@nongnu.org Bogus image may have a large total_sectors that will overflow the multiplication. For cleanness, fix the return code so the error message will be meaningful. Reported-by: Richard W.M. Jones Signed-off-by: Fam Zheng --- block.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block.c b/block.c index 7904098..5ee3fdf 100644 --- a/block.c +++ b/block.c @@ -2330,6 +2330,7 @@ int64_t bdrv_getlength(BlockDriverState *bs) { int64_t ret = bdrv_nb_sectors(bs); + ret = (int64_t)(ret * BDRV_SECTOR_SIZE) < 0 ? -EFBIG : ret; return ret < 0 ? ret : ret * BDRV_SECTOR_SIZE; } -- 2.4.0