From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0C7DC433DF for ; Mon, 13 Jul 2020 12:46:13 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 995C82072D for ; Mon, 13 Jul 2020 12:46:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FCX3e2t4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 995C82072D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49580 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1juxqW-0008SN-UN for qemu-devel@archiver.kernel.org; Mon, 13 Jul 2020 08:46:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38056) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1juxpt-00080J-BH for qemu-devel@nongnu.org; Mon, 13 Jul 2020 08:45:33 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:32786 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1juxpr-0002hX-U5 for qemu-devel@nongnu.org; Mon, 13 Jul 2020 08:45:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1594644330; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:content-type:content-type; bh=LONTUp8NUv0Dvbr8PRvKUQdw1nxlPMBo58bws25E+ms=; b=FCX3e2t4RX5p6xWXcWxqocmufid3ASp0WvzPP93cuHdXylNRlpshjAs+JR3bPLrsjisOIG OiPV7p08sBBsTZ5MCchVvLFBu5TjmdQFxlsfBC3DVEsbKs6GAYIy2pTWbS4enz0qx7UA8Y dilan2KMyH8yV03vjxVmdwZKmnJVnj8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-416-3yiOv0_dMgKMCQg7wZkW4w-1; Mon, 13 Jul 2020 08:45:28 -0400 X-MC-Unique: 3yiOv0_dMgKMCQg7wZkW4w-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3EC1F1080 for ; Mon, 13 Jul 2020 12:45:27 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-115-89.ams2.redhat.com [10.36.115.89]) by smtp.corp.redhat.com (Postfix) with ESMTP id F415E5C221; Mon, 13 Jul 2020 12:45:20 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 246EE3F119; Mon, 13 Jul 2020 14:45:20 +0200 (CEST) From: Gerd Hoffmann To: qemu-devel@nongnu.org Subject: [PATCH] vfio: fix use-after-free in display Date: Mon, 13 Jul 2020 14:45:20 +0200 Message-Id: <20200713124520.23266-1-kraxel@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Received-SPF: pass client-ip=205.139.110.120; envelope-from=kraxel@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/13 03:20:22 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alex Williamson , Gerd Hoffmann Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Calling ramfb_display_update() might replace the DisplaySurface with the boot display, which in turn will free the currently active DisplaySurface. So clear our DisplaySurface pinter (dpy->region.surface pointer) to (a) avoid use-after-free and (b) force replacing the boot display with the real display when switching back. Signed-off-by: Gerd Hoffmann --- hw/vfio/display.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/vfio/display.c b/hw/vfio/display.c index a57a22674d62..342054193b3c 100644 --- a/hw/vfio/display.c +++ b/hw/vfio/display.c @@ -405,6 +405,7 @@ static void vfio_display_region_update(void *opaque) if (!plane.drm_format || !plane.size) { if (dpy->ramfb) { ramfb_display_update(dpy->con, dpy->ramfb); + dpy->region.surface = NULL; } return; } -- 2.18.4