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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 F2D0EC433DB for ; Thu, 4 Mar 2021 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 94B1664F2B for ; Thu, 4 Mar 2021 10:38:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94B1664F2B 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]:43424 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lHlMu-0006tc-Js for qemu-devel@archiver.kernel.org; Thu, 04 Mar 2021 05:38:08 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53880) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lHlM3-0006Ss-I6 for qemu-devel@nongnu.org; Thu, 04 Mar 2021 05:37:15 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:27285) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lHlM1-0002Xs-T0 for qemu-devel@nongnu.org; Thu, 04 Mar 2021 05:37:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614854233; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3Roq+e5ho9PiYSTbzwlWTn8T6D9zPApFFxhcs7RzPWw=; b=F7lZzIaRzoIXWjqHgwHiAnu9hQV4ZN0OlBKi51OfSYNqw4wTX9BSntGbMX9iTAvanpxPnM KMoVtDa3eDfIZhhlIl1v7XQE6p0/Wz3E7xjxH3FyIDsUYrgVkrI3M0XZPo7Xmt/vbtLUD2 DVtl7v3v5GNwjbuEGAgIg4/GsZKr05E= 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-167-1YsN3SrHN-CVEJcJIqvI4A-1; Thu, 04 Mar 2021 05:37:08 -0500 X-MC-Unique: 1YsN3SrHN-CVEJcJIqvI4A-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7CF4D108BD13; Thu, 4 Mar 2021 10:37:07 +0000 (UTC) Received: from redhat.com (ovpn-115-33.ams2.redhat.com [10.36.115.33]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5952319C48; Thu, 4 Mar 2021 10:37:06 +0000 (UTC) Date: Thu, 4 Mar 2021 10:37:03 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Daniele Buono Subject: Re: [PATCH] meson: Stop if cfi is enabled with system slirp Message-ID: References: <20210304025939.9164-1-dbuono@linux.vnet.ibm.com> MIME-Version: 1.0 In-Reply-To: <20210304025939.9164-1-dbuono@linux.vnet.ibm.com> User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Paolo Bonzini , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Mar 03, 2021 at 09:59:38PM -0500, Daniele Buono wrote: > For CFI, we need to compile slirp as a static library together with qemu. > This is because we register slirp functions as callbacks for QEMU Timers. > When using a system-wide shared libslirp, the type information for the > callback is missing and the timer call produces a false positive with CFI. Is there work being done, or at least an active plan, for fixing this ? Distros generally won't want to static link slirp to QEMU when there is a shared slirp available. It increases the security burden to maintain slirp twice, especially as slirp has a history of CVEs. IOW, the inability to use shared slirp may well prevent CFI from being used in distros. > > With this patch, meson will stop if CFI is enabled with system-wide slirp > > Signed-off-by: Daniele Buono > --- > meson.build | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/meson.build b/meson.build > index f3db83e974..e1ec5020ac 100644 > --- a/meson.build > +++ b/meson.build > @@ -1569,6 +1569,18 @@ if have_system > endif > endif > > +# For CFI, we need to compile slirp as a static library together with qemu. > +# This is because we register slirp functions as callbacks for QEMU Timers. > +# When using a system-wide shared libslirp, the type information for the > +# callback is missing and the timer call produces a false positive with CFI. > +# > +# Now that slirp_opt has been defined, check if the selected slirp is compatible > +# with control-flow integrity. > +if get_option('cfi') and slirp_opt == 'system' > + error('Control-Flow Integrity is not compatible with system-wide slirp.' \ > + + ' Please configure with --enable-slirp=git') > +endif Reviewed-by: Daniel P. Berrangé Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|