Re: [PATCH 2.6.13.1] Patch for invisible threads

Daniel Jacobowitz
2005-09-16T18:05:46Z

On Fri, Sep 16, 2005 at 08:46:06AM +0100, Al Viro wrote:
> > Further, about actual permission checks that we are doing, can we say: "A
> > process should be able to see /proc/<pid>/task/* of another process only if
> > they both belong to same uid or reader is root"? But any such change will
> > change the behavior of commands like 'ps', right?
>
> Right. The real question is whether the current behaviour makes any sense.
> I've no objections to your patch + modification above, but I really wonder
> if we should keep current rules in that area.

Why should there be any more restrictions on /proc/<pid>/task than
there are in /proc? Threads are not listed in the latter, but that's
strictly for performance/usability; you can enumerate threads in /proc
by just trying all the valid PIDs.

--
Daniel Jacobowitz
CodeSourcery, LLC