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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>,
        Andy Lutomirski <luto@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org,
        kernel list <linux-kernel@vger.kernel.org>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Akinobu Mita <akinobu.mita@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Jeff Layton <jlayton@poochiereds.net>,
        Ingo Molnar <mingo@kernel.org>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        aniel Micay <danielmicay@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>, bfields@fieldses.org,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Solar Designer <solar@openwall.com>,
        "Dmitry V. Levin" <ldv@altlinux.org>,
        Djalal Harouni <tixxdz@gmail.com>
Subject: Re: [PATCH v5 7/7] proc: add option to mount only a pids subset
Message-ID: <20180514090117.GC28179@comp-core-i7-2640m-0182e6>
References: <20180511093707.GA1403@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