From patchwork Mon Jun 24 09:02:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Igor Mammedov X-Patchwork-Id: 11012639 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3C1A9924 for ; Mon, 24 Jun 2019 09:02:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DFF528A1D for ; Mon, 24 Jun 2019 09:02:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 220AE28B4C; Mon, 24 Jun 2019 09:02:54 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D08A528A1D for ; Mon, 24 Jun 2019 09:02:53 +0000 (UTC) Received: from localhost ([::1]:48909 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hfKsH-0004oL-2Q for patchwork-qemu-devel@patchwork.kernel.org; Mon, 24 Jun 2019 05:02:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48632) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hfKri-0003ut-2D for qemu-devel@nongnu.org; Mon, 24 Jun 2019 05:02:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hfKrh-0002SH-1S for qemu-devel@nongnu.org; Mon, 24 Jun 2019 05:02:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39782) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hfKrg-00023a-Pg for qemu-devel@nongnu.org; Mon, 24 Jun 2019 05:02:16 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 00D1C308FEE2; Mon, 24 Jun 2019 09:02:07 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq.redhat.com (dell-r430-03.lab.eng.brq.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 132B85D9CC; Mon, 24 Jun 2019 09:02:02 +0000 (UTC) From: Igor Mammedov To: qemu-devel@nongnu.org Date: Mon, 24 Jun 2019 05:02:00 -0400 Message-Id: <20190624090200.5383-1-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Mon, 24 Jun 2019 09:02:12 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2] pc: fix possible NULL pointer dereference in pc_machine_get_device_memory_region_size() 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: pbonzini@redhat.com, rth@twiddle.net, ehabkost@redhat.com, armbru@redhat.com, mst@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP QEMU will crash when device-memory-region-size property is read if ms->device_memory wasn't initialized yet. Crash can be reproduced with: $QEMU -preconfig -qmp unix:qmp_socket,server,nowait & ./scripts/qmp/qom-get -s qmp_socket /machine.device-memory-region-size Instead of crashing return 0 if ms->device_memory hasn't been initialized. Signed-off-by: Igor Mammedov Reviewed-by: Philippe Mathieu-Daudé --- v2: * fix missing return value assignment (Eduardo Habkost ) --- hw/i386/pc.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index e96360b47a..552f3401e2 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -2458,7 +2458,11 @@ pc_machine_get_device_memory_region_size(Object *obj, Visitor *v, Error **errp) { MachineState *ms = MACHINE(obj); - int64_t value = memory_region_size(&ms->device_memory->mr); + int64_t value = 0; + + if (ms->device_memory) { + value = memory_region_size(&ms->device_memory->mr); + } visit_type_int(v, name, &value, errp); }