Subject: Re: [PATCH v2 1/2] mm: mmap: Add new /proc tunable for mmap_base
 ASLR.
To: "Eric W. Biederman" <ebiederm@xmission.com>,
        Michal Hocko <mhocko@kernel.org>
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 <877flxo9j5.fsf@x220.int.ebiederm.org>
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From: Daniel Cashman <dcashman@android.com>
Message-ID: <563A5E27.2060607@android.com>
Date: Wed, 4 Nov 2015 11:36:07 -0800
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On 11/4/15 11:21 AM, Eric W. Biederman wrote:
> Michal Hocko <mhocko@kernel.org> writes:
> 
>> On Tue 03-11-15 10:10:03, Daniel Cashman wrote:
>> [...]
>>> +This value can be changed after boot using the
>>> +/proc/sys/kernel/mmap_rnd_bits tunable
>>
>> Why is this not sitting in /proc/sys/vm/ where we already have
>> mmap_min_addr. These two sound like they should sit together, no?
> 
> Ugh.  Yes.  Moving that file before it becomes part of the ABI sounds
> like a good idea.  Daniel when you get around to v3 please move the
> file.

To answer the first question: it was put there because that's where
randomize_va_space is located, which seemed to me to be the
most-related/similar option.  That being said, moving it under vm works
too.  Will change for patch-set 3.

Thank You,
Dan

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