Re: [RFC 0/8] Aufs2 documents

[Matthew Wilcox <matthew@wil.cx>]

On Wed, Feb 25, 2009 at 12:50:54PM -0500, David P. Quigley wrote:
> I think it would be useful to see the source code for AUFS2 posted to
> LKML. One of the questions I have not which doesn't seem to be addressed
> in these documents is how robust is your xattr support and are you
> making the appropriate LSM calls to make this usable with SELinux and
> Smack. Also from a labeling perspective you have a very interesting
> question of which label do you select when unifying directories. If you
> have a/foo and b/foo each with different labels which do you choose.
> Based on the history of Union type file systems I would suspect the
> answer is whichever branch is listed first. 

That would provide an interesting way to bypass security protections on
a directory.  I suspect it should deny access if *any* of the unioned
directories would deny access.

-- 
Matthew Wilcox				Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."