From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zombie.ncsc.mil (zombie.ncsc.mil [144.51.88.131]) by tarius.tycho.ncsc.mil (8.13.1/8.13.1) with ESMTP id m0FMNG46024562 for ; Tue, 15 Jan 2008 17:23:16 -0500 Received: from web36614.mail.mud.yahoo.com (jazzdrum.ncsc.mil [144.51.5.7]) by zombie.ncsc.mil (8.12.10/8.12.10) with SMTP id m0FMNEJK002070 for ; Tue, 15 Jan 2008 22:23:14 GMT Date: Tue, 15 Jan 2008 14:23:14 -0800 (PST) From: Casey Schaufler Reply-To: casey@schaufler-ca.com Subject: Re: [PATCH 08/28] SECURITY: Allow kernel services to override LSM settings for task actions [try #2] To: David Howells , Stephen Smalley Cc: dhowells@redhat.com, casey@schaufler-ca.com, Daniel J Walsh , linux-kernel@vger.kernel.org, selinux@tycho.nsa.gov, linux-security-module@vger.kernel.org In-Reply-To: <6778.1200434110@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Message-ID: <372376.51168.qm@web36614.mail.mud.yahoo.com> Sender: owner-selinux@tycho.nsa.gov List-Id: selinux@tycho.nsa.gov --- David Howells wrote: > Stephen Smalley wrote: > > > The cache files are created by the cachefiles kernel module, not by the > > userspace daemon, and the userspace daemon doesn't need to directly > > read/write them at all > > That is correct. > > > (but I think it does need to be able to unlink them?). > > Indeed. > > > The userspace daemon merely identifies the directory where the cache should > > live as part of configuring the cache when enabling it. > > That is the way it currently works, yes. > > > Hence, it is fine to use a fixed label for the cache files (systemhigh > > in a MLS world), and to let the directory's label serve as the basis for > > it. > > That is what I currently do. SELinux rules are provided to grant the > appropriate file accesses to the override label used by the kernel module, so > that it can't go and stamp on files with the wrong label. > > > Only the cachefiles kernel module directly reads and writes the files. > > Correct. Well, my bad, and thank you for clearing up my misunderstanding. Casey Schaufler casey@schaufler-ca.com -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@tycho.nsa.gov with the words "unsubscribe selinux" without quotes as the message. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759275AbYAOWXa (ORCPT ); Tue, 15 Jan 2008 17:23:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753843AbYAOWXU (ORCPT ); Tue, 15 Jan 2008 17:23:20 -0500 Received: from web36614.mail.mud.yahoo.com ([209.191.85.31]:47494 "HELO web36614.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1758567AbYAOWXS (ORCPT ); Tue, 15 Jan 2008 17:23:18 -0500 X-YMail-OSG: VSHNMgAVM1k7jx7w..EY4QHFulFKzEWOXabF4XNPDI8mFztPlIvdLG5bX72o5GZT8.FlXBr_wQ-- X-RocketYMMF: rancidfat Date: Tue, 15 Jan 2008 14:23:14 -0800 (PST) From: Casey Schaufler Reply-To: casey@schaufler-ca.com Subject: Re: [PATCH 08/28] SECURITY: Allow kernel services to override LSM settings for task actions [try #2] To: David Howells , Stephen Smalley Cc: dhowells@redhat.com, casey@schaufler-ca.com, Daniel J Walsh , linux-kernel@vger.kernel.org, selinux@tycho.nsa.gov, linux-security-module@vger.kernel.org In-Reply-To: <6778.1200434110@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Message-ID: <372376.51168.qm@web36614.mail.mud.yahoo.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --- David Howells wrote: > Stephen Smalley wrote: > > > The cache files are created by the cachefiles kernel module, not by the > > userspace daemon, and the userspace daemon doesn't need to directly > > read/write them at all > > That is correct. > > > (but I think it does need to be able to unlink them?). > > Indeed. > > > The userspace daemon merely identifies the directory where the cache should > > live as part of configuring the cache when enabling it. > > That is the way it currently works, yes. > > > Hence, it is fine to use a fixed label for the cache files (systemhigh > > in a MLS world), and to let the directory's label serve as the basis for > > it. > > That is what I currently do. SELinux rules are provided to grant the > appropriate file accesses to the override label used by the kernel module, so > that it can't go and stamp on files with the wrong label. > > > Only the cachefiles kernel module directly reads and writes the files. > > Correct. Well, my bad, and thank you for clearing up my misunderstanding. Casey Schaufler casey@schaufler-ca.com