Re: Nokia N900: refcount_t underflow, use after free

[Suman Anna]

On 05/24/2018 06:05 AM, Pavel Machek wrote:
> Hi!
> 
>>>>
>>>> OK, see if the following fixes the issue for you, only build tested.
>>>
>>> Word-wrapped, so I applied by hand. And yes, the oops at boot is
>>> gone. Thanks!
>>
>> Sorry about that, have to check my mail settings. Anyway will post the
>> patch again, glad that it fixed your issue.
> 
> Any news here? AFAICT the bug creeped into v4.17-rcX in the
> meantime...
>

The patch has been on linux-next for sometime now.

regards
Suman

> 								Pavel
> 
>> regards
>> Suman
>>
>>>
>>> (Camera still does not work in -next... kills system. Oh well. Lets
>>> debug that some other day.)
>>>
>>>> 8< ---------------------
>>>> >From bac9a48fb646dc51f2030d676a0dbe3298c3b134 Mon Sep 17 00:00:00 2001
>>>> From: Suman Anna <s-anna@xxxxxx>
>>>> Date: Fri, 9 Mar 2018 16:39:59 -0600
>>>> Subject: [PATCH] media: omap3isp: fix unbalanced dma_iommu_mapping
>>>>
>>>> The OMAP3 ISP driver manages its MMU mappings through the IOMMU-aware
>>>> ARM DMA backend. The current code creates a dma_iommu_mapping and
>>>> attaches this to the ISP device, but never detaches the mapping in
>>>> either the probe failure paths or the driver remove path resulting
>>>> in an unbalanced mapping refcount and a memory leak. Fix this properly.
>>>>
>>>> Reported-by: Pavel Machek <pavel@xxxxxx>
>>>> Signed-off-by: Suman Anna <s-anna@xxxxxx>
>>>
>>> Tested-by: Pavel Machek <pavel@xxxxxx>
>>> 									Pavel
>>>
>