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=-2.2 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 4976DC67839 for ; Thu, 13 Dec 2018 03:02:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0CC9A20851 for ; Thu, 13 Dec 2018 03:02:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gB/wt+5I" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0CC9A20851 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-security-module-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726510AbeLMDCe (ORCPT ); Wed, 12 Dec 2018 22:02:34 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:45556 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726380AbeLMDCe (ORCPT ); Wed, 12 Dec 2018 22:02:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Transfer-Encoding :Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=wkjviKf3aN2mLDkPF2pxE5QaInJ9Yf6kITrXLVMxCPw=; b=gB/wt+5Im+cEhdT9AemjcOfZgN Am+dd4FhSjE6bAz1t0Kj8e0CCLIOY+aojdW69PA0iFtcde0CWfM8BDMuELOKQtL/FF8WO7WwNr/zF rJueWqQVAA/bg+FMm/FfpbTmTBqM8/0RDr6UxB6f/9FqoXa3D6+Oj+WWzWdA7/nvaZGUMkJwTCWJ9 rKVS13MR5qHNp/U4eHK/73A5HZ3ai/CwpR4NtmwjMD497WTi3aMHOpBC3GSrS7iG92wnBdAWDsssG lh+XRq62T7WqeR4cB/dPkGY98P59txz7nJwcxG7c3hxS5yn2Itvq4ZXyHhNPIzlO0mzUOGl+DUGsI bdwp70Tw==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gXHGe-0006LC-Ht; Thu, 13 Dec 2018 03:02:28 +0000 Date: Wed, 12 Dec 2018 19:02:28 -0800 From: Matthew Wilcox To: =?iso-8859-1?Q?Micka=EBl_Sala=FCn?= Cc: linux-kernel@vger.kernel.org, Al Viro , James Morris , Jonathan Corbet , Kees Cook , Matthew Garrett , Michael Kerrisk , =?iso-8859-1?Q?Micka=EBl_Sala=FCn?= , Mimi Zohar , Philippe =?iso-8859-1?Q?Tr=E9buchet?= , 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 Message-ID: <20181213030228.GM6830@bombadil.infradead.org> References: <20181212081712.32347-1-mic@digikod.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20181212081712.32347-1-mic@digikod.net> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Wed, Dec 12, 2018 at 09:17:07AM +0100, Mickaël Salaün wrote: > The goal of this patch series is to control script interpretation. A > new O_MAYEXEC flag used by sys_open() is added to enable userland script > interpreter to delegate to the kernel (and thus the system security > policy) the permission to interpret scripts or other files containing > what can be seen as commands. I don't have a problem with the concept, but we're running low on O_ bits. Does this have to be done before the process gets a file descriptor, or could we have a new syscall? Since we're going to be changing the interpreters anyway, it doesn't seem like too much of an imposition to ask them to use: int verify_for_exec(int fd) instead of adding an O_MAYEXEC.