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Date: Sun, 23 Oct 2011 16:21:59 +1100
From: Kevin Easton <kevin@guarana.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Roland McGrath <roland@hack.frob.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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        John Johansen <john.johansen@canonical.com>,
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Subject: Re: [PATCH 1/2] LSM: Do not apply mmap_min_addr check to PROT_NONE
 mappings
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Quoting Linus Torvalds <torvalds@linux-foundation.org>:

> [ Resent, this seems to have gotten dropped by something. Sorry if it
> shows up twice  ]

My fault, looks like lkml.org trims the CC list to an unreasonably small
value.

> On Sun, Oct 23, 2011 at 2:08 AM, Kevin Easton <kevin@guarana.org> wrote:
>>
>> Won't this still allow silent probing, because the malicious user can
>> just try to create the mapping, then check in /proc/self/maps to see
>> if it really worked?
>
> Yup, right you are.
>
> So we shouldn't do that either, and probably just leave the current
> semantics, unless Roland (or others) can convince me that complicating
> the kernel  mmap security model really is worth it.
>
>             Linus