From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752216AbbCJCgU (ORCPT <rfc822;w@1wt.eu>);
	Mon, 9 Mar 2015 22:36:20 -0400
Received: from mga01.intel.com ([192.55.52.88]:55822 "EHLO mga01.intel.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751295AbbCJCgP (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Mon, 9 Mar 2015 22:36:15 -0400
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.11,371,1422950400"; 
   d="scan'208";a="689517998"
Message-ID: <54FE589C.1050705@linux.intel.com>
Date: Mon, 09 Mar 2015 19:36:12 -0700
From: Dave Hansen <dave.hansen@linux.intel.com>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0
MIME-Version: 1.0
To: Andy Lutomirski <luto@amacapital.net>, Kees Cook <keescook@chromium.org>
CC: "Kirill A. Shutemov" <kirill@shutemov.name>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Linux-MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Pavel Emelyanov <xemul@parallels.com>,
        Konstantin Khlebnikov <khlebnikov@openvz.org>,
        Mark Seaborn <mseaborn@chromium.org>
Subject: Re: [RFC, PATCH] pagemap: do not leak physical addresses to non-privileged
 userspace
References: <1425935472-17949-1-git-send-email-kirill@shutemov.name> <CAGXu5jLvHa0fAV9sBwW5AvzkJY1AvQyhBmrRHLZWAtw5=-9aZg@mail.gmail.com> <CALCETrU_3FS6B7LtkAwdC3e8xfiwdhPjkVWPgxP1Vy2uPeqMtA@mail.gmail.com>
In-Reply-To: <CALCETrU_3FS6B7LtkAwdC3e8xfiwdhPjkVWPgxP1Vy2uPeqMtA@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 03/09/2015 05:19 PM, Andy Lutomirski wrote:
> per-pidns like this is no good.  You shouldn't be able to create a
> non-paranoid pidns if your parent is paranoid.

That sounds like a reasonable addition that shouldn't be hard to add.

> Also, at some point we need actual per-ns controls.  This mount option
> stuff is hideous.

So,

	per-pidns == bad
	per-ns == good

If the pid namespace is the wrong place, which namespace is the right place?