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Date: Fri, 03 Jul 2009 10:38:48 +0800
From: Li Zefan <lizf@cn.fujitsu.com>
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To: "Serge E. Hallyn" <serge@hallyn.com>
CC: Andrew Morton <akpm@linux-foundation.org>, Paul Menage <menage@google.com>,
       Linux Containers <containers@lists.linux-foundation.org>,
       Benjamin Blum <bblum@google.com>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] cgroups: fix pid namespace bug, fix
References: <4A4D61C7.4090409@cn.fujitsu.com> <20090703024304.GA27802@hallyn.com>
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>>  	cp->cgrp = cgrp;
>> -	cp->pid_ns = pid_ns;
>> +	cp->ns = ns;
> 
> Why not just do
> 
> 	cp->ns = get_pid_ns(ns);
> 
> here instead of getting and putting at (1) and (2) ?
> 
> Both are correct, but this way will take a bit more
> work to verify every time someone comes to look at this.
> 
> In fact, (just noticed) yours isn't right, because at (3) you
> will leak the pidns reference.
> 

My bad. :(

I did the quick fix without thinking it more.

And I noticed seemingly the similar bug exists in Benjamin's patch...