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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 C8666C2BC61 for ; Tue, 30 Oct 2018 16:39:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F56120823 for ; Tue, 30 Oct 2018 16:39:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7F56120823 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727710AbeJaBdm (ORCPT ); Tue, 30 Oct 2018 21:33:42 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33416 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726501AbeJaBdm (ORCPT ); Tue, 30 Oct 2018 21:33:42 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4AD024E90D; Tue, 30 Oct 2018 16:39:30 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.31]) by smtp.corp.redhat.com (Postfix) with SMTP id B9A0D5D757; Tue, 30 Oct 2018 16:39:27 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Tue, 30 Oct 2018 17:39:29 +0100 (CET) Date: Tue, 30 Oct 2018 17:39:26 +0100 From: Oleg Nesterov To: Tycho Andersen Cc: Kees Cook , Andy Lutomirski , "Eric W . Biederman" , "Serge E . Hallyn" , Christian Brauner , Tyler Hicks , Akihiro Suda , Aleksa Sarai , linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, linux-api@vger.kernel.org Subject: Re: [PATCH v8 1/2] seccomp: add a return code to trap to userspace Message-ID: <20181030163926.GC7643@redhat.com> References: <20181029224031.29809-1-tycho@tycho.ws> <20181029224031.29809-2-tycho@tycho.ws> <20181030150254.GB3385@redhat.com> <20181030155403.GC7343@cisco> <20181030162752.GB7643@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181030162752.GB7643@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 30 Oct 2018 16:39:30 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/30, Oleg Nesterov wrote: > > On 10/30, Tycho Andersen wrote: > > > > @@ -828,6 +823,11 @@ static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, > > */ > > rmb(); > > > > + if (!sd) { > > + populate_seccomp_data(&sd_local); > > + sd = &sd_local; > > + } > > + > > To me it would be more clean to remove the "if (!sd)" check, case(SECCOMP_RET_TRACE) > in __seccomp_filter() can simply do populate_seccomp_data(&sd_local) unconditionally > and pass &sd_local to __seccomp_filter(). Ah, please ignore, emulate_vsyscall() does secure_computing(NULL). Btw. why __seccomp_filter() doesn't return a boolean? Or at least, why can't case(SECCOMP_RET_TRACE) simply do return __seccomp_filter(this_syscall, NULL, true); ? Oleg.