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Date: Mon, 14 May 2018 11:01:17 +0200
From: Alexey Gladkov <gladkov.alexey@gmail.com>
To: Jann Horn <jannh@google.com>
Cc: Kees Cook <keescook@chromium.org>,
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Subject: Re: [PATCH v5 7/7] proc: add option to mount only a pids subset
Message-ID: <20180514090117.GC28179@comp-core-i7-2640m-0182e6>
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On Fri, May 11, 2018 at 03:58:39PM +0200, Jann Horn wrote:
> On Fri, May 11, 2018 at 11:37 AM, Alexey Gladkov
> <gladkov.alexey@gmail.com> wrote:
> > This allows to hide all files and directories in the procfs that are not
> > related to tasks.
> 
> /proc/$pid/net and /proc/$pid/task/$tid/net aren't in scope for this
> protection, even though they contain information about the whole
> network namespace of the task, right?

Yes. The pidonly makes visible only pids subset. You can still access the
process namespaces via /proc/$pid/ns.

We can think of additional constraints since the parameters are not
stored in the pid namespace anymore.

-- 
Rgrds, legion