From patchwork Mon Jan 11 05:31:12 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 565645 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 826A41402BF for ; Mon, 11 Jan 2016 16:44:28 +1100 (AEDT) Received: from localhost ([::1]:51726 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aIVHG-0006Kz-G3 for incoming@patchwork.ozlabs.org; Mon, 11 Jan 2016 00:44:26 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36656) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aIV6v-00030U-R3 for qemu-devel@nongnu.org; Mon, 11 Jan 2016 00:33:46 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aIV6v-0008SF-1e for qemu-devel@nongnu.org; Mon, 11 Jan 2016 00:33:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35461) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aIV6u-0008SB-T0; Mon, 11 Jan 2016 00:33:44 -0500 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 849843B715; Mon, 11 Jan 2016 05:33:44 +0000 (UTC) Received: from jason-ThinkPad-T430s.nay.redhat.com (dhcp-15-133.nay.redhat.com [10.66.15.133]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u0B5VfLm018161; Mon, 11 Jan 2016 00:33:40 -0500 From: Jason Wang To: peter.maydell@linaro.org, qemu-devel@nongnu.org Date: Mon, 11 Jan 2016 13:31:12 +0800 Message-Id: <1452490275-18217-22-git-send-email-jasowang@redhat.com> In-Reply-To: <1452490275-18217-1-git-send-email-jasowang@redhat.com> References: <1452490275-18217-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Jason Wang , Prasad J Pandit , qemu-stable@nongnu.org Subject: [Qemu-devel] [PULL 21/24] net: rocker: fix an incorrect array bounds check 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: Prasad J Pandit While processing transmit(tx) descriptors in 'tx_consume' routine the switch emulator suffers from an off-by-one error, if a descriptor was to have more than allowed(ROCKER_TX_FRAGS_MAX=16) fragments. Fix an incorrect bounds check to avoid it. Reported-by: Qinghao Tang Cc: qemu-stable@nongnu.org Signed-off-by: Prasad J Pandit Signed-off-by: Jason Wang --- hw/net/rocker/rocker.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/hw/net/rocker/rocker.c b/hw/net/rocker/rocker.c index c57f1a6..2e77e50 100644 --- a/hw/net/rocker/rocker.c +++ b/hw/net/rocker/rocker.c @@ -232,6 +232,9 @@ static int tx_consume(Rocker *r, DescInfo *info) frag_addr = rocker_tlv_get_le64(tlvs[ROCKER_TLV_TX_FRAG_ATTR_ADDR]); frag_len = rocker_tlv_get_le16(tlvs[ROCKER_TLV_TX_FRAG_ATTR_LEN]); + if (iovcnt >= ROCKER_TX_FRAGS_MAX) { + goto err_too_many_frags; + } iov[iovcnt].iov_len = frag_len; iov[iovcnt].iov_base = g_malloc(frag_len); if (!iov[iovcnt].iov_base) { @@ -244,10 +247,7 @@ static int tx_consume(Rocker *r, DescInfo *info) err = -ROCKER_ENXIO; goto err_bad_io; } - - if (++iovcnt > ROCKER_TX_FRAGS_MAX) { - goto err_too_many_frags; - } + iovcnt++; } if (iovcnt) {