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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 0AED5C33CA2 for ; Wed, 8 Jan 2020 18:59:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E132320678 for ; Wed, 8 Jan 2020 18:59:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729668AbgAHS7H (ORCPT ); Wed, 8 Jan 2020 13:59:07 -0500 Received: from namei.org ([65.99.196.166]:56264 "EHLO namei.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726401AbgAHS7G (ORCPT ); Wed, 8 Jan 2020 13:59:06 -0500 Received: from localhost (localhost [127.0.0.1]) by namei.org (8.14.4/8.14.4) with ESMTP id 008IwTZG029133; Wed, 8 Jan 2020 18:58:29 GMT Date: Thu, 9 Jan 2020 05:58:29 +1100 (AEDT) From: James Morris To: Stephen Smalley cc: Kees Cook , KP Singh , Casey Schaufler , open list , bpf , linux-security-module@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Thomas Garnier , Michael Halcrow , Paul Turner , Brendan Gregg , Jann Horn , Matthew Garrett , Christian Brauner , =?ISO-8859-15?Q?Micka=EBl_Sala=FCn?= , Florent Revest , Brendan Jackman , Martin KaFai Lau , Song Liu , Yonghong Song , "Serge E. Hallyn" , Mauro Carvalho Chehab , "David S. Miller" , Greg Kroah-Hartman , Nicolas Ferre , Stanislav Fomichev , Quentin Monnet , Andrey Ignatov , Joe Stringer , Paul Moore Subject: Re: [PATCH bpf-next v1 00/13] MAC and Audit policy using eBPF (KRSI) In-Reply-To: Message-ID: References: <20191220154208.15895-1-kpsingh@chromium.org> <95036040-6b1c-116c-bd6b-684f00174b4f@schaufler-ca.com> <201912301112.A1A63A4@keescook> User-Agent: Alpine 2.21 (LRH 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 8 Jan 2020, Stephen Smalley wrote: > This appears to impose a very different standard to this eBPF-based LSM than > has been applied to the existing LSMs, e.g. we are required to preserve > SELinux policy compatibility all the way back to Linux 2.6.0 such that new > kernel with old policy does not break userspace. If that standard isn't being > applied to the eBPF-based LSM, it seems to inhibit its use in major Linux > distros, since otherwise users will in fact start experiencing breakage on the > first such incompatible change. Not arguing for or against, just trying to > make sure I understand correctly... A different standard would be applied here vs. a standard LSM like SELinux, which are retrofitted access control systems. I see KRSI as being more of a debugging / analytical API, rather than an access control system. You could of course build such a system with KRSI but it would need to provide a layer of abstraction for general purpose users. So yes this would be a special case, as its real value is in being a special case, i.e. dynamic security telemetry. -- James Morris