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Date: Fri, 16 Sep 2005 14:05:35 -0400
From: Daniel Jacobowitz <dan@debian.org>
To: Al Viro <viro@ftp.linux.org.uk>
Cc: Sripathi Kodi <sripathik@in.ibm.com>, Al Viro <viro@ZenIV.linux.org.uk>,
       Linus Torvalds <torvalds@osdl.org>, Andrew Morton <akpm@osdl.org>,
       linux-kernel@vger.kernel.org, patrics@interia.pl,
       Ingo Molnar <mingo@elte.hu>, Roland McGrath <roland@redhat.com>
Subject: Re: [PATCH 2.6.13.1] Patch for invisible threads
Message-ID: <20050916180535.GA10430@nevyn.them.org>
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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
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