Subject: Re: [AppArmor 39/45] AppArmor: Profile loading and manipulation,
	pathname matching
From: Stephen Smalley <sds@tycho.nsa.gov>
To: Lars Marowsky-Bree <lmb@suse.de>
Cc: James Morris <jmorris@namei.org>, Pavel Machek <pavel@ucw.cz>,
       Crispin Cowan <crispin@novell.com>, Greg KH <greg@kroah.com>,
       Andreas Gruenbacher <agruen@suse.de>, jjohansen@suse.de,
       linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org,
       linux-fsdevel@vger.kernel.org
In-Reply-To: <20070621211743.GN20105@marowsky-bree.de>
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Content-Type: text/plain
Organization: National Security Agency
Date: Fri, 22 Jun 2007 07:19:39 -0400
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On Thu, 2007-06-21 at 23:17 +0200, Lars Marowsky-Bree wrote:
> On 2007-06-21T16:59:54, Stephen Smalley <sds@tycho.nsa.gov> wrote:
> 
> > Or can access the data under a different path to which their profile
> > does give them access, whether in its final destination or in some
> > temporary file processed along the way.
> 
> Well, yes. That is intentional.
> 
> Your point is?

It may very well be unintentional access, especially when taking into
account wildcards in profiles and user-writable directories.

> > The emphasis on never modifying applications for security in AA likewise
> > has an adverse impact here, as you will ultimately have to deal with
> > application mediation of access to their own objects and operations not
> > directly visible to the kernel (as we have already done in SELinux for
> > D-BUS and others and are doing for X).  Otherwise, your "protection" of
> > desktop applications is easily subverted.
> 
> That is an interesting argument, but not what we're discussing here.
> We're arguing filesystem access mediation.

IOW, anything that AA cannot protect against is "out of scope".  An easy
escape from any criticism.

> > Um, no.  It might not be able to directly open files via that path, but
> > showing that it can never read or write your mail is a rather different
> > matter.
> 
> Yes. Your use case is different than mine.

My use case is being able to protect data reliably.  Yours?

-- 
Stephen Smalley
National Security Agency

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