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=-0.8 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 CC80FC67837 for ; Thu, 11 Oct 2018 23:48:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 927AA2077C for ; Thu, 11 Oct 2018 23:48:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 927AA2077C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=canonical.com 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 S1727248AbeJLHSC (ORCPT ); Fri, 12 Oct 2018 03:18:02 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:58814 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725830AbeJLHSC (ORCPT ); Fri, 12 Oct 2018 03:18:02 -0400 Received: from static-50-53-48-205.bvtn.or.frontiernet.net ([50.53.48.205] helo=[192.168.192.153]) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1gAkgn-0002fR-UF; Thu, 11 Oct 2018 23:48:22 +0000 Subject: Re: [PATCH security-next v5 00/30] LSM: Explict ordering To: Kees Cook , Jordan Glover Cc: James Morris , Casey Schaufler , Stephen Smalley , Paul Moore , Tetsuo Handa , Mimi Zohar , Randy Dunlap , LSM , "open list:DOCUMENTATION" , linux-arch , LKML References: <20181011001846.30964-1-keescook@chromium.org> From: John Johansen Openpgp: preference=signencrypt Autocrypt: addr=john.johansen@canonical.com; prefer-encrypt=mutual; keydata= xsFNBE5mrPoBEADAk19PsgVgBKkImmR2isPQ6o7KJhTTKjJdwVbkWSnNn+o6Up5knKP1f49E BQlceWg1yp/NwbR8ad+eSEO/uma/K+PqWvBptKC9SWD97FG4uB4/caomLEU97sLQMtnvGWdx rxVRGM4anzWYMgzz5TZmIiVTZ43Ou5VpaS1Vz1ZSxP3h/xKNZr/TcW5WQai8u3PWVnbkjhSZ PHv1BghN69qxEPomrJBm1gmtx3ZiVmFXluwTmTgJOkpFol7nbJ0ilnYHrA7SX3CtR1upeUpM a/WIanVO96WdTjHHIa43fbhmQube4txS3FcQLOJVqQsx6lE9B7qAppm9hQ10qPWwdfPy/+0W 6AWtNu5ASiGVCInWzl2HBqYd/Zll93zUq+NIoCn8sDAM9iH+wtaGDcJywIGIn+edKNtK72AM gChTg/j1ZoWH6ZeWPjuUfubVzZto1FMoGJ/SF4MmdQG1iQNtf4sFZbEgXuy9cGi2bomF0zvy BJSANpxlKNBDYKzN6Kz09HUAkjlFMNgomL/cjqgABtAx59L+dVIZfaF281pIcUZzwvh5+JoG eOW5uBSMbE7L38nszooykIJ5XrAchkJxNfz7k+FnQeKEkNzEd2LWc3QF4BQZYRT6PHHga3Rg ykW5+1wTMqJILdmtaPbXrF3FvnV0LRPcv4xKx7B3fGm7ygdoowARAQABzR1Kb2huIEpvaGFu c2VuIDxqb2huQGpqbXgubmV0PsLBegQTAQoAJAIbAwULCQgHAwUVCgkICwUWAgMBAAIeAQIX gAUCTo0YVwIZAQAKCRAFLzZwGNXD2LxJD/9TJZCpwlncTgYeraEMeDfkWv8c1IsM1j0AmE4V tL+fE780ZVP9gkjgkdYSxt7ecETPTKMaZSisrl1RwqU0oogXdXQSpxrGH01icu/2n0jcYSqY KggPxy78BGs2LZq4XPfJTZmHZGnXGq/eDr/mSnj0aavBJmMZ6jbiPz6yHtBYPZ9fdo8btczw P41YeWoIu26/8II6f0Xm3VC5oAa8v7Rd+RWZa8TMwlhzHExxel3jtI7IzzOsnmE9/8Dm0ARD 5iTLCXwR1cwI/J9BF/S1Xv8PN1huT3ItCNdatgp8zqoJkgPVjmvyL64Q3fEkYbfHOWsaba9/ kAVtBNz9RTFh7IHDfECVaToujBd7BtPqr+qIjWFadJD3I5eLCVJvVrrolrCATlFtN3YkQs6J n1AiIVIU3bHR8Gjevgz5Ll6SCGHgRrkyRpnSYaU/uLgn37N6AYxi/QAL+by3CyEFLjzWAEvy Q8bq3Iucn7JEbhS/J//dUqLoeUf8tsGi00zmrITZYeFYARhQMtsfizIrVDtz1iPf/ZMp5gRB niyjpXn131cm3M3gv6HrQsAGnn8AJru8GDi5XJYIco/1+x/qEiN2nClaAOpbhzN2eUvPDY5W 0q3bA/Zp2mfG52vbRI+tQ0Br1Hd/vsntUHO903mMZep2NzN3BZ5qEvPvG4rW5Zq2DpybWc7B TQROZqz6ARAAoqw6kkBhWyM1fvgamAVjeZ6nKEfnRWbkC94L1EsJLup3Wb2X0ABNOHSkbSD4 pAuC2tKF/EGBt5CP7QdVKRGcQzAd6b2c1Idy9RLw6w4gi+nn/d1Pm1kkYhkSi5zWaIg0m5RQ Uk+El8zkf5tcE/1N0Z5OK2JhjwFu5bX0a0l4cFGWVQEciVMDKRtxMjEtk3SxFalm6ZdQ2pp2 822clnq4zZ9mWu1d2waxiz+b5Ia4weDYa7n41URcBEUbJAgnicJkJtCTwyIxIW2KnVyOrjvk QzIBvaP0FdP2vvZoPMdlCIzOlIkPLgxE0IWueTXeBJhNs01pb8bLqmTIMlu4LvBELA/veiaj j5s8y542H/aHsfBf4MQUhHxO/BZV7h06KSUfIaY7OgAgKuGNB3UiaIUS5+a9gnEOQLDxKRy/ a7Q1v9S+Nvx+7j8iH3jkQJhxT6ZBhZGRx0gkH3T+F0nNDm5NaJUsaswgJrqFZkUGd2Mrm1qn KwXiAt8SIcENdq33R0KKKRC80Xgwj8Jn30vXLSG+NO1GH0UMcAxMwy/pvk6LU5JGjZR73J5U LVhH4MLbDggD3mPaiG8+fotTrJUPqqhg9hyUEPpYG7sqt74Xn79+CEZcjLHzyl6vAFE2W0kx lLtQtUZUHO36afFv8qGpO3ZqPvjBUuatXF6tvUQCwf3H6XMAEQEAAcLBXwQYAQoACQUCTmas +gIbDAAKCRAFLzZwGNXD2D/XD/0ddM/4ai1b+Tl1jznKajX3kG+MeEYeI4f40vco3rOLrnRG FOcbyyfVF69MKepie4OwoI1jcTU0ADecnbWnDNHpr0SczxBMro3bnrLhsmvjunTYIvssBZtB 4aVJjuLILPUlnhFqa7fbVq0ZQjbiV/rt2jBENdm9pbJZ6GjnpYIcAbPCCa/ffL4/SQRSYHXo hGiiS4y5jBTmK5ltfewLOw02fkexH+IJFrrGBXDSg6n2Sgxnn++NF34fXcm9piaw3mKsICm+ 0hdNh4afGZ6IWV8PG2teooVDp4dYih++xX/XS8zBCc1O9w4nzlP2gKzlqSWbhiWpifRJBFa4 WtAeJTdXYd37j/BI4RWWhnyw7aAPNGj33ytGHNUf6Ro2/jtj4tF1y/QFXqjJG/wGjpdtRfbt UjqLHIsvfPNNJq/958p74ndACidlWSHzj+Op26KpbFnmwNO0psiUsnhvHFwPO/vAbl3RsR5+ 0Ro+hvs2cEmQuv9r/bDlCfpzp2t3cK+rhxUqisOx8DZfz1BnkaoCRFbvvvk+7L/fomPntGPk qJciYE8TGHkZw1hOku+4OoM2GB5nEDlj+2TF/jLQ+EipX9PkPJYvxfRlC6dK8PKKfX9KdfmA IcgHfnV1jSn+8yH2djBPtKiqW0J69aIsyx7iV/03paPCjJh7Xq9vAzydN5U/UA== Organization: Canonical Message-ID: Date: Thu, 11 Oct 2018 16:48:14 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On 10/11/2018 04:09 PM, Kees Cook wrote: > On Thu, Oct 11, 2018 at 3:58 PM, Jordan Glover > wrote: >> On Thursday, October 11, 2018 7:57 PM, Kees Cook wrote: >>> To switch to SELinux at boot time with >>> "CONFIG_LSM=yama,loadpin,integrity,apparmor", the old way continues to >>> work: >>> >>> selinux=1 security=selinux >>> >>> This will work still, since it will enable selinux (selinux=1) and >>> disable all other major LSMs (security=selinux). >>> >>> The new way to enable selinux would be using >>> "lsm=yama,loadpin,integrity,selinux". >>> >> >> It seems to me that legacy way is more user friendly than the new one. >> AppArmor and SElinux are households names but the rest may be enigmatic >> for most users and the need for explicit passing them all may be >> troublesome. Especially when the new ones like sara,landlock or cows :) >> will be incoming. Moreover to knew what you have to pass there, you need >> to look at CONFIG_LSM in kernel config (which will vary across distros >> and also mean copy-paste from the web source may won't work as expected) >> which again most users don't do. >> >> I think there is risk that users will end up with "lsm=selinux" without >> realizing that they may disable something along the way. >> >> I would prefer for "lsm=" to work as override to "CONFIG_LSM=" with >> below assumptions: >> >> I. lsm="$lsm" will append "$lsm" at the end of string. Before extreme >> stacking it will also remove the other major (explicit) lsm from it. >> >> II. lsm="!$lsm" will remove "$lsm" from the string. >> >> III. If "$lsm" already exist in the string, it's moved at the end of it >> (this will cover ordering). > > We've had things sort of like this proposed, but if you can convince > James and others, I'm all for it. I think the standing objection from > James and John about this is that the results of booting with > "lsm=something" ends up depending on CONFIG_LSM= for that distro. So > you end up with different behaviors instead of a consistent behavior > across all distros. > Its certainly a point that could confuse the user. I do have concerns about it, but not something that is on a must haves list > Now, in the future blob and extreme stacking world, having the > explicit lsm= list shouldn't be too bad since LSMs will effectively > ALL be initialized -- but they'll be inactive since they have no > policy loaded. > you are more optimistic about this than I am, but there will be at least some movement towards this. > But I still agree with you: I'd like a friendlier way to > disable/enable specific LSMs, but an explicit lsm= seems to be the > only way. > Hrmmm, I don't know about the only way, but a way to provide the explicit list, and also set a specific set as the default in the Kconfig is a hard requirement. The initial lsm.ebable, lsm.disable had too many issues, and for various reasons I never managed to get back to kees' proposal for using +. That said, I do think the right approach for the initial pass is the explicit list. It moves the arguments to the side and allows this work to move forward. >> It's possible that something lime this was discussed already >> but without full examples it was hard to me for tracking things. > > It's been a painful thread. ;) > Indeed