From nobody Mon Apr 29 02:30:50 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 148593818685360.64299992200745; Wed, 1 Feb 2017 00:36:26 -0800 (PST) Received: from localhost ([::1]:43271 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cYqOt-0007yS-P1 for importer@patchew.org; Wed, 01 Feb 2017 03:36:23 -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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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 CirrusVGAStat= e *s, } if (pitch < 0) { int64_t min =3D addr - + ((int64_t)s->cirrus_blt_height-1) * pitch; - int32_t max =3D 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 >=3D s->vga.vram_size) { return true; } } else { --=20 1.8.3.1