Message-ID: <48916DAE.3020406@cn.fujitsu.com>
Date: Thu, 31 Jul 2008 15:45:50 +0800
From: Lai Jiangshan <laijs@cn.fujitsu.com>
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To: Li Zefan <lizf@cn.fujitsu.com>
CC: Andrew Morton <akpm@linux-foundation.org>, Paul Jackson <pj@sgi.com>,
       Paul Menage <menage@google.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] cpuset: make ntasks to be a monotonic increasing value
References: <48912FDD.8060006@cn.fujitsu.com> <48916557.8070508@cn.fujitsu.com>
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Er, I can't. But this attack is existence theoretically indeed.
And IMO a monotonic increasing value is very helpful for this loop.


Li Zefan wrote:
> Lai Jiangshan wrote:
>> ntasks is not a monotonic increasing value,
>> So maybe fudge+1 processes are created when kmalloc and killed
>> when kfree in every loop. And the loop will not end or
>> repetition a long time.
>>
>> This patch prevent this kind of attack.
>>
> 
> Could you demonstrate how to manage to do this so-called attack in
> real-life?
> 
> 
> 
> 


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