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_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 2A4BFC73C53 for ; Tue, 9 Jul 2019 17:09:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0AEBA20651 for ; Tue, 9 Jul 2019 17:09:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726444AbfGIRJT (ORCPT ); Tue, 9 Jul 2019 13:09:19 -0400 Received: from mga14.intel.com ([192.55.52.115]:24541 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726335AbfGIRJT (ORCPT ); Tue, 9 Jul 2019 13:09:19 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Jul 2019 10:09:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,470,1557212400"; d="scan'208";a="173621923" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.165]) by FMSMGA003.fm.intel.com with ESMTP; 09 Jul 2019 10:09:17 -0700 Date: Tue, 9 Jul 2019 10:09:17 -0700 From: Sean Christopherson To: Jarkko Sakkinen Cc: linux-sgx@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, Bill Roberts , Casey Schaufler , James Morris , Dave Hansen , Cedric Xing , Andy Lutomirski , Jethro Beekman , "Dr . Greg Wettstein" , Stephen Smalley Subject: Re: [RFC PATCH v4 00/12] security: x86/sgx: SGX vs. LSM Message-ID: <20190709170917.GD25369@linux.intel.com> References: <20190619222401.14942-1-sean.j.christopherson@intel.com> <20190705160549.tzsck5ho5kvtdhit@linux.intel.com> <20190708172930.GA20791@linux.intel.com> <20190709162203.gzyvulah5u7eksip@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190709162203.gzyvulah5u7eksip@linux.intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org On Tue, Jul 09, 2019 at 07:22:03PM +0300, Jarkko Sakkinen wrote: > On Mon, Jul 08, 2019 at 10:29:30AM -0700, Sean Christopherson wrote: > > On Fri, Jul 05, 2019 at 07:05:49PM +0300, Jarkko Sakkinen wrote: > > > On Wed, Jun 19, 2019 at 03:23:49PM -0700, Sean Christopherson wrote: > > > > > > I still don't get why we need this whole mess and do not simply admit > > > that there are two distinct roles: > > > > > > 1. Creator > > > 2. User > > > > Because SELinux has existing concepts of EXECMEM and EXECMOD. > > What is the official documentation for those? I've only found some > explanations from discussions and some RHEL sysadmin guides. No clue. My knowledge was gleaned from the code and from Stephen's feedback. The high level breakdown: - FILE__EXECUTE: required to gain X on a mapping to a regular file - FILE__EXECUTE + FILE__WRITE: required to gain WX or W->X on a shared mapping to a regular file - FILE__EXECMOD: required to gain W->X on a private mapping of a regular file - PROCESS__EXECMEM: required to gain WX on a private mapping to a regular file, OR to gain X on an anonymous mapping. Translating those to SGX, with a lot of input from Stephen, I ended up with the following: - FILE__ENCLAVE_EXECUTE: equivalent to FILE__EXECUTE, required to gain X on an enclave page loaded from a regular file - PROCESS2__ENCLAVE_EXECDIRTY: hybrid of EXECMOD and EXECUTE+WRITE, required to gain W->X on an enclave page - PROCESS2__ENCLAVE_EXECANON: subset of EXECMEM, required to gain X on an enclave page that is loaded from an anonymous mapping - PROCESS2__ENCLAVE_MAPWX: subset of EXECMEM, required to gain WX on an enclave page > > That being said, we can do so without functional changes to the SGX uapi, > > e.g. add reserved fields so that the initial uapi can be extended *if* we > > decide to go with the "userspace provides maximal protections" path, and > > use the EPCM permissions as the maximal protections for the initial > > upstreaming. > > > > That'd give us a minimal implemenation for initial upstreaming and would > > eliminate Cedric's blocking complaint. The "whole mess" of whitelisting, > > blacklisting and SGX2 support would be deferred until post-upstreaming. > > I'd like that approach more too. > > /Jarkko