From patchwork Tue Jul 8 17:18:30 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 368090 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 10F5E140087 for ; Wed, 9 Jul 2014 13:46:05 +1000 (EST) Received: from localhost ([::1]:58889 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4ipX-0000nh-4O for incoming@patchwork.ozlabs.org; Tue, 08 Jul 2014 23:46:03 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41704) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4Z72-0004xq-1s for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:24:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X4Z6G-0000ys-2r for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:23:27 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:50705) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4Z6F-0000yL-UD for qemu-devel@nongnu.org; Tue, 08 Jul 2014 13:22:39 -0400 Received: from /spool/local by e7.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 8 Jul 2014 13:22:39 -0400 Received: from d01dlp03.pok.ibm.com (9.56.250.168) by e7.ny.us.ibm.com (192.168.1.107) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Tue, 8 Jul 2014 13:22:38 -0400 Received: from b01cxnp22036.gho.pok.ibm.com (b01cxnp22036.gho.pok.ibm.com [9.57.198.26]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id D6E8EC90040; Tue, 8 Jul 2014 13:22:30 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by b01cxnp22036.gho.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s68HMb9r58720398; Tue, 8 Jul 2014 17:22:37 GMT Received: from d01av03.pok.ibm.com (localhost [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s68HMbnk006291; Tue, 8 Jul 2014 13:22:37 -0400 Received: from localhost ([9.41.105.211]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id s68HMaKK006240; Tue, 8 Jul 2014 13:22:36 -0400 From: Michael Roth To: qemu-devel@nongnu.org Date: Tue, 8 Jul 2014 12:18:30 -0500 Message-Id: <1404839947-1086-120-git-send-email-mdroth@linux.vnet.ibm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1404839947-1086-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1404839947-1086-1-git-send-email-mdroth@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14070817-5806-0000-0000-00002556D2BC X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 32.97.182.137 Cc: qemu-stable@nongnu.org Subject: [Qemu-devel] [PATCH 119/156] qcow1: Validate image size (CVE-2014-0223) 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: Kevin Wolf A huge image size could cause s->l1_size to overflow. Make sure that images never require a L1 table larger than what fits in s->l1_size. This cannot only cause unbounded allocations, but also the allocation of a too small L1 table, resulting in out-of-bounds array accesses (both reads and writes). Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf (cherry picked from commit 46485de0cb357b57373e1ca895adedf1f3ed46ec) Signed-off-by: Michael Roth --- block/qcow.c | 16 ++++++++++++++-- tests/qemu-iotests/092 | 9 +++++++++ tests/qemu-iotests/092.out | 7 +++++++ 3 files changed, 30 insertions(+), 2 deletions(-) diff --git a/block/qcow.c b/block/qcow.c index 73a96a0..2840386 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -61,7 +61,7 @@ typedef struct BDRVQcowState { int cluster_sectors; int l2_bits; int l2_size; - int l1_size; + unsigned int l1_size; uint64_t cluster_offset_mask; uint64_t l1_table_offset; uint64_t *l1_table; @@ -163,7 +163,19 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, /* read the level 1 table */ shift = s->cluster_bits + s->l2_bits; - s->l1_size = (header.size + (1LL << shift) - 1) >> shift; + if (header.size > UINT64_MAX - (1LL << shift)) { + error_setg(errp, "Image too large"); + ret = -EINVAL; + goto fail; + } else { + uint64_t l1_size = (header.size + (1LL << shift) - 1) >> shift; + if (l1_size > INT_MAX / sizeof(uint64_t)) { + error_setg(errp, "Image too large"); + ret = -EINVAL; + goto fail; + } + s->l1_size = l1_size; + } s->l1_table_offset = header.l1_table_offset; s->l1_table = g_malloc(s->l1_size * sizeof(uint64_t)); diff --git a/tests/qemu-iotests/092 b/tests/qemu-iotests/092 index fb8bacc..ae6ca76 100755 --- a/tests/qemu-iotests/092 +++ b/tests/qemu-iotests/092 @@ -43,6 +43,7 @@ _supported_fmt qcow _supported_proto generic _supported_os Linux +offset_size=24 offset_cluster_bits=32 offset_l2_bits=33 @@ -72,6 +73,14 @@ poke_file "$TEST_IMG" "$offset_l2_bits" "\x0e" poke_file "$TEST_IMG" "$offset_l2_bits" "\x1b" { $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir +echo +echo "== Invalid size ==" +_make_test_img 64M +poke_file "$TEST_IMG" "$offset_size" "\xee\xee\xee\xee\xee\xee\xee\xee" +{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir +poke_file "$TEST_IMG" "$offset_size" "\x7f\xff\xff\xff\xff\xff\xff\xff" +{ $QEMU_IO -c "write 0 64M" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/092.out b/tests/qemu-iotests/092.out index 73918b3..ac03302 100644 --- a/tests/qemu-iotests/092.out +++ b/tests/qemu-iotests/092.out @@ -21,4 +21,11 @@ qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 an no file open, try 'help open' qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 and 64k no file open, try 'help open' + +== Invalid size == +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 +qemu-io: can't open device TEST_DIR/t.qcow: Image too large +no file open, try 'help open' +qemu-io: can't open device TEST_DIR/t.qcow: Image too large +no file open, try 'help open' *** done