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From: Yann Droneaud <ydroneaud@opteya.com>
To: stable@vger.kernel.org
Cc: Will Deacon <will.deacon@arm.com>,
	Matthias Brugger <mbrugger@suse.com>
Date: Wed, 15 Jul 2015 11:54:19 +0200
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Subject: Re: arm64/mm: Remove hack in mmap randomize layout
Sender: stable-owner@vger.kernel.org
List-ID: <stable.vger.kernel.org>

Hi,

Le lundi 13 juillet 2015 à 17:07 +0200, Matthias Brugger a écrit :
> 
> Commit d6c763afab14 "arm64/mm: Remove hack in mmap randomize layout" 
> fixes a security issue which reduces the entropy for mmap base 
> address by half [1].
> A attempt to guess where the stack is mapped via brute-force needs 
> just half the attempts.
> 
> I found this patch was added to v3.19-rc1 but should be added as well 
> to:
> v3.18, v3.14, v3.12 and v3.10
> 

I agree.

The issue fixed by commit d6c763afab142a85e4770b4bc2a5f40f256d5c5d is
present since v3.7-rc1.

> [1] http://hmarco.org/bugs/linux-ASLR-reducing-mmap-by-half.html

Regards.

-- 
Yann Droneaud
OPTEYA