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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 087DBC76192 for ; Wed, 17 Jul 2019 10:38:09 +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 D39762077C for ; Wed, 17 Jul 2019 10:38:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D39762077C 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]:55808 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hnhK4-0006QR-30 for qemu-devel@archiver.kernel.org; Wed, 17 Jul 2019 06:38:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56525) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hnhJu-0005zv-FM for qemu-devel@nongnu.org; Wed, 17 Jul 2019 06:37:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hnhJt-0002bh-IM for qemu-devel@nongnu.org; Wed, 17 Jul 2019 06:37:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54636) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hnhJt-0002bQ-Cp for qemu-devel@nongnu.org; Wed, 17 Jul 2019 06:37:57 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id B67D35AFE9; Wed, 17 Jul 2019 10:37:56 +0000 (UTC) Received: from redhat.com (ovpn-120-247.rdu2.redhat.com [10.10.120.247]) by smtp.corp.redhat.com (Postfix) with SMTP id 53D375C26B; Wed, 17 Jul 2019 10:37:54 +0000 (UTC) Date: Wed, 17 Jul 2019 06:37:47 -0400 From: "Michael S. Tsirkin" To: Igor Mammedov Message-ID: <20190717063733-mutt-send-email-mst@kernel.org> References: <20190624090200.5383-1-imammedo@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190624090200.5383-1-imammedo@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 17 Jul 2019 10:37:56 +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: Re: [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, qemu-devel@nongnu.org, armbru@redhat.com, ehabkost@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Jun 24, 2019 at 05:02:00AM -0400, Igor Mammedov wrote: > 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 queued, thanks! > --- > > 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); > } > -- > 2.18.1