Re: [Umbrella-devel] Re: Getting full path from dentry in LSM hooks

["Kristian Sørensen" <ks@cs.aau.dk>]

Christoph Hellwig wrote:
> On Fri, Sep 03, 2004 at 09:54:23PM +0200, Kristian Sørensen wrote:
> 
>>>>We are working on a project called Umbrella, (umbrella.sf.net) which 
>>>>implements processbased mandatory accesscontrol in the Linux kernel. 
>>>>This access control is controlled by "restriction", e.g. by restricting 
>>>> some process from accessing any given file or directory.
>>>>
>>>>E.g. if a root owned process is restricted from accessing /var/www, and 
>>>>the process is compromised by an attacker, no mater what he does, he 
>>>>would not be able to access this directory.
>>>
>>>
>>>mount --bind /var/www /home/joe/p0rn/, and then?
>>
>>Actually this "attack" is avoided, because restrictions are enherited, 
>>from parent proces to its children.
> 
> 
> If you restrict your process on the path /var/ww/ but the same objects
> are also available below a different path, what does that have to do with
> child processes?
Well nothing :-) The point was, that links and mount bindings are 
handled, and if the parent is restricted from accessing a file, the 
child is too.

KS.