[PATCH 1/3] powerpc/mm: Don't alias user region to other regions below PAGE_OFFSET

[Aneesh Kumar K.V]

Paul Mackerras <paulus at ozlabs.org> writes:

> On Fri, Sep 02, 2016 at 05:52:16PM +0530, Aneesh Kumar K.V wrote:
>> 
>> Hi Paul,
>> 
>> Really nice catch. Was this found by code analysis or do we have any
>> reported issue around this ?
>
> I found it by code analysis.
>
> I haven't been able to find any really bad consequence, beyond leaking
> some information about kernel memory.  Can you find any worse
> consequence?
>

No, considering linux page table entry is not going to have a mapping
for this address.

-aneesh