From patchwork Wed Feb 1 08:35:01 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gerd Hoffmann X-Patchwork-Id: 9549069 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6C7E260425 for ; Wed, 1 Feb 2017 08:35:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5F66B2811C for ; Wed, 1 Feb 2017 08:35:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 53F55280FC; Wed, 1 Feb 2017 08:35:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 66404280FC for ; Wed, 1 Feb 2017 08:35:45 +0000 (UTC) Received: from localhost ([::1]:43269 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cYqOG-0007Zs-1u for patchwork-qemu-devel@patchwork.kernel.org; Wed, 01 Feb 2017 03:35:44 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58904) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cYqNv-0007Zm-8g for qemu-devel@nongnu.org; Wed, 01 Feb 2017 03:35:24 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cYqNr-0001Mo-BO for qemu-devel@nongnu.org; Wed, 01 Feb 2017 03:35:23 -0500 Received: from mx1.redhat.com ([209.132.183.28]:38322) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cYqNr-0001MV-60; Wed, 01 Feb 2017 03:35:19 -0500 Received: from smtp.corp.redhat.com (int-mx16.intmail.prod.int.phx2.redhat.com [10.5.11.28]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2FAF761BA2; Wed, 1 Feb 2017 08:35:19 +0000 (UTC) Received: from nilsson.home.kraxel.org (ovpn-116-59.ams2.redhat.com [10.36.116.59]) by smtp.corp.redhat.com (Postfix) with ESMTP id 29A3A1BE863; Wed, 1 Feb 2017 08:35:17 +0000 (UTC) Received: by nilsson.home.kraxel.org (Postfix, from userid 500) id 55C0380D7D; Wed, 1 Feb 2017 09:35:10 +0100 (CET) From: Gerd Hoffmann To: qemu-devel@nongnu.org Date: Wed, 1 Feb 2017 09:35:01 +0100 Message-Id: <1485938101-26602-1-git-send-email-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.74 on 10.5.11.28 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 01 Feb 2017 08:35:19 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3] cirrus: fix oob access issue (CVE-2017-2615) X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Wolfgang Bumiller , Li Qiang , qemu-stable@nongnu.org, P J P , Gerd Hoffmann , Paolo Bonzini , Laszlo Ersek Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Li Qiang When doing bitblt copy in backward mode, we should minus the blt width first just like the adding in the forward mode. This can avoid the oob access of the front of vga's vram. Signed-off-by: Li Qiang Message-id: 5887254f.863a240a.2c122.5500@mx.google.com { kraxel: with backward blits (negative pitch) addr is the topmost address, so check it as-is against vram size ] Cc: qemu-stable@nongnu.org Cc: P J P Cc: Laszlo Ersek Cc: Paolo Bonzini Cc: Wolfgang Bumiller Fixes: d3532a0db02296e687711b8cdc7791924efccea0 (CVE-2014-8106) Signed-off-by: Gerd Hoffmann Reviewed-by: Laszlo Ersek --- hw/display/cirrus_vga.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c index 95873ae..3961712 100644 --- a/hw/display/cirrus_vga.c +++ b/hw/display/cirrus_vga.c @@ -277,10 +277,9 @@ static bool blit_region_is_unsafe(struct CirrusVGAState *s, } if (pitch < 0) { int64_t min = addr - + ((int64_t)s->cirrus_blt_height-1) * pitch; - int32_t max = addr - + s->cirrus_blt_width; - if (min < 0 || max > s->vga.vram_size) { + + ((int64_t)s->cirrus_blt_height - 1) * pitch + - s->cirrus_blt_width; + if (min < -1 || addr >= s->vga.vram_size) { return true; } } else {