Re: Security: information leaks in /proc enable keystroke recovery

[Arjan van de Ven]

On Mon, 17 Aug 2009 12:45:45 +1000 (EST)
James Morris <jmorris@xxxxxxxxx> wrote:

> On Sun, 16 Aug 2009, Theodore Tso wrote:
> 
> > On Mon, Aug 17, 2009 at 12:31:38AM +0000, David Wagner wrote:
> > > 
> > > OK.  What about this:
> > > 
> > > (a) Remove ESP and EIP from /proc/$pid/stat{,us} entirely.  Put
> > > them in some other file that is only readable by root and by the
> > > owner of the process, but is not world-readable.  We know that
> > > ESP and EIP can be used for keystroke recovery, and they are not
> > > usually used by administrators, so the first step is to lock them
> > > down tightly: there is no downside.
> > 
> > Agreed.
> 
> It might be best to require a capability for this if not root.
> 
> The candidates seem to be CAP_SYS_ADMIN and CAP_SYS_PTRACE.

I would suggest we just use the "can ptrace" permission function
altogether... (after all, if you can ptrace an app you already own all
its keys)


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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