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=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 BF965C6783B for ; Wed, 12 Dec 2018 20:13:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E09C20851 for ; Wed, 12 Dec 2018 20:13:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E09C20851 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 S1727913AbeLLUN0 (ORCPT ); Wed, 12 Dec 2018 15:13:26 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57088 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726247AbeLLUN0 (ORCPT ); Wed, 12 Dec 2018 15:13:26 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AEB853154871; Wed, 12 Dec 2018 20:13:25 +0000 (UTC) Received: from oldenburg2.str.redhat.com (ovpn-116-48.ams2.redhat.com [10.36.116.48]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 332F06012B; Wed, 12 Dec 2018 20:13:18 +0000 (UTC) From: Florian Weimer To: James Morris Cc: =?utf-8?Q?Micka=C3=ABl_Sala=C3=BCn?= , linux-kernel@vger.kernel.org, Al Viro , Jonathan Corbet , Kees Cook , Matthew Garrett , Michael Kerrisk , =?utf-8?Q?Micka=C3=ABl_Sala=C3=BCn?= , Mimi Zohar , Philippe =?utf-8?Q?Tr=C3=A9buchet?= , Shuah Khan , Thibaut Sautereau , Vincent Strubel , Yves-Alexis Perez , kernel-hardening@lists.openwall.com, linux-api@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFC PATCH v1 0/5] Add support for O_MAYEXEC References: <20181212081712.32347-1-mic@digikod.net> Date: Wed, 12 Dec 2018 21:13:16 +0100 In-Reply-To: (James Morris's message of "Thu, 13 Dec 2018 06:51:53 +1100 (AEDT)") Message-ID: <87lg4upkpv.fsf@oldenburg2.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Wed, 12 Dec 2018 20:13:26 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * James Morris: > If you're depending on the script interpreter to flag that the user may > execute code, this seems to be equivalent in security terms to depending > on the user. e.g. what if the user uses ptrace and clears O_MAYEXEC? The argument I've heard is this: Using ptrace (and adding the +x attribute) are auditable events. Florian