Message-ID: <43F99586.9050308@sw.ru>
Date: Mon, 20 Feb 2006 13:10:14 +0300
From: Kirill Korotaev <dev@sw.ru>
User-Agent: Mozilla/5.0 (X11; U; Linux i686; ru-RU; rv:1.2.1) Gecko/20030426
MIME-Version: 1.0
To: Dave Hansen <haveblue@us.ibm.com>
CC: Herbert Poetzl <herbert@13thfloor.at>,
       "Eric W. Biederman" <ebiederm@xmission.com>,
       "Serge E. Hallyn" <serue@us.ibm.com>, linux-kernel@vger.kernel.org,
       vserver@list.linux-vserver.org, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Arjan van de Ven <arjan@infradead.org>,
       Suleiman Souhlal <ssouhlal@FreeBSD.org>,
       Hubertus Franke <frankeh@watson.ibm.com>,
       Cedric Le Goater <clg@fr.ibm.com>, Kyle Moffett <mrmacman_g4@mac.com>,
       Greg <gkurz@fr.ibm.com>, Linus Torvalds <torvalds@osdl.org>,
       Andrew Morton <akpm@osdl.org>, Greg KH <greg@kroah.com>,
       Rik van Riel <riel@redhat.com>, Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
       Andrey Savochkin <saw@sawoct.com>, Kirill Korotaev <dev@openvz.org>,
       Andi Kleen <ak@suse.de>,
       Benjamin Herrenschmidt <benh@kernel.crashing.org>,
       Jeff Garzik <jgarzik@pobox.com>,
       Trond Myklebust <trond.myklebust@fys.uio.no>,
       Jes Sorensen <jes@sgi.com>
Subject: Re: (pspace,pid) vs true pid virtualization
References: <20060215145942.GA9274@sergelap.austin.ibm.com>	 <m11wy4s24i.fsf@ebiederm.dsl.xmission.com>	 <20060216143030.GA27585@MAIL.13thfloor.at> <1140111692.21383.2.camel@localhost.localdomain>
In-Reply-To: <1140111692.21383.2.camel@localhost.localdomain>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 841
Lines: 21

>>this is mandatory, as it is required to kill any process
>>from the host (admin) context, without entering the pid
>>space (which would lead to all kind of security issues) 
> 
> 
> Giving admin processes the ability to enter pid spaces seems like it
> solves an entire class of problems, right?.  Could you explain a bit
> what kinds of security issues it introduces?
Enter is not always possible.
For example when you have exhausted your resources in VPS.
(e.g. hit process limit inside).
And you can't make enter without resource limitations, since it will be 
a security hole then.

Kirill

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/