From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754970Ab1ILVeN (ORCPT ); Mon, 12 Sep 2011 17:34:13 -0400 Received: from nm12-vm0.access.bullet.mail.mud.yahoo.com ([66.94.236.11]:32498 "HELO nm12-vm0.access.bullet.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754638Ab1ILVeK (ORCPT ); Mon, 12 Sep 2011 17:34:10 -0400 X-Yahoo-Newman-Id: 192362.21172.bm@smtp103.biz.mail.bf1.yahoo.com X-Yahoo-Newman-Property: ymail-3 X-YMail-OSG: Z5PfZO4VM1lX8ksU2sUmT0an39aQJVsIj3KcQ3.Ui9vEHo8 mg05hFOROQYYMhR0d_RNdayuSDdv8k1M4tzyYZe8sdkngAgZgX83htkjRmWL QP0bTpyFjBHWhcKIxykyIbDqyd6ZPqshzgHyxNy62Lhrr_s6l2vOOJAfZckI 06hb17pMGH2fSilnZjRn4x00qbseOda6vUto2ypiRl10RlJF_EtsjiFWeuKI rYnaF.ZByAwPhtPDAWbWoa9FhFo.ZJZd0EYQWhjclBP045T0NZxMRt0EUZAe oY9XFAiMezbVp2Ya7QnXtZpaMk.v.8uG7NJJYVyRZc9cEaVo4I7ffoQu074e 1zwh8kybNSXV4WtHYcDY9vJPc5HsDacAHNtyRspUR03VKOD7DsMrmX_HvEm5 w500.zCJy X-Yahoo-SMTP: OIJXglSswBDfgLtXluJ6wiAYv6_cnw-- Message-ID: <4E6E7ACC.8040003@schaufler-ca.com> Date: Mon, 12 Sep 2011 14:34:04 -0700 From: Casey Schaufler User-Agent: Mozilla/5.0 (Windows NT 6.0; rv:6.0.2) Gecko/20110902 Thunderbird/6.0.2 MIME-Version: 1.0 To: Valdis.Kletnieks@vt.edu CC: "Aneesh Kumar K.V" , agruen@kernel.org, bfields@fieldses.org, akpm@linux-foundation.org, dhowells@redhat.com, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, LSM , Casey Schaufler Subject: Re: [PATCH -V6 00/26] New ACL format for better NFSv4 acl interoperability References: <1315243548-18664-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <4E655049.6060507@schaufler-ca.com> <108028.1315442771@turing-police.cc.vt.edu> In-Reply-To: <108028.1315442771@turing-police.cc.vt.edu> X-Enigmail-Version: 1.3.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/7/2011 5:46 PM, Valdis.Kletnieks@vt.edu wrote: > On Mon, 05 Sep 2011 15:42:17 PDT, Casey Schaufler said: >> On 9/5/2011 10:25 AM, Aneesh Kumar K.V wrote: >>> The following set of patches implements VFS and ext4 changes needed to implement >>> a new acl model for linux. Rich ACLs are an implementation of NFSv4 ACLs, >>> extended by file( masks to fit into the standard POSIX file permission model. >>> They are designed to work seamlessly locally as well as across the NFSv4 and >>> CIFS/SMB2 network file system protocols. >> >> POSIX ACLs predate the LSM and can't be done as an LSM due to >> the interactions between mode bits and ACLs as defined by the >> POSIX DRAFT specification. Is there a reason that "rich" ACLs >> can not be done as an LSM? > > Well, if it was done as an LSM, it would mean that if I wanted to build a > system where I have a few hundred terabytes of disk exported via Samba, and I > wanted Samba to save the CIFS permission ACL, I couldn't also run Selinux or > SMACK or anything like that - unless somebody actually snuck in the "LSMs are > stackable" patch while I wasn't looking? > True, but not an acceptable argument for not doing it as an LSM. It is an argument in favor of LSM stacking, and after the Linux Security Summit this past week it seems only a matter of time before we have that. This could be the compelling use case that we've been missing for LSM stacking. So at this point, unless there is another reason why it can't be an LSM it should be an LSM.