Re: [PATCH] dma-mapping: Add BUG_ON for uninitialized dma_ops

[Michal Simek <monstr@monstr.eu>]

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On 06/19/2013 05:20 PM, Arnd Bergmann wrote:
> On Friday 14 June 2013, James Bottomley wrote:
>> This is the MMAP_PAGE_ZERO exploit.  The original exploit relied on a
>> leaky personality capability clearing mask and was fixed in 2.6.31 by
>>
>> commit f9fabcb58a6d26d6efde842d1703ac7cfa9427b6
>> Author: Julien Tinnes <jt@cr0.org>
>> Date:   Fri Jun 26 20:27:40 2009 +0200
>>
>>     personality: fix PER_CLEAR_ON_SETID
>>
>> So it's not really relevant to 3.x kernels, is it?
> 
> Probably not. There is always a risk that something like this
> can turn into an exploit, but it needs a combination with a couple
> of other bugs.

ok. Let me refresh this thread.
We have middle solution where some functions have this checking
and some not.
Based on get_maintainer scripts Arnd should do that decision
to accept or reject this patch.

Arnd: Can you please decide if you want it or not?
Based on that you can just add this one or we can create new one
which remove BUG_ON(!ops) from that file.

Thanks,
Michal


-- 
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/
Maintainer of Linux kernel - Xilinx Zynq ARM architecture
Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform



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