Re: [PATCH] drm: Use kvzalloc for allocating blob property memory

From: Michel DÃnzer
Date: Fri Jun 29 2018 - 12:27:37 EST


On 2018-06-29 06:12 PM, Ville SyrjÃlà wrote:
> On Fri, Jun 29, 2018 at 04:27:10PM +0200, Michel DÃnzer wrote:
>> From: Michel DÃnzer <michel.daenzer@xxxxxxx>
>>
>> The property size may be controlled by userspace, can be large (I've
>> seen failure with order 4, i.e. 16 pages / 64 KB) and doesn't need to be
>> physically contiguous.
>
> I wonder if we should enforce some kind of reasonable limit
> on the blob size. Looks like we allow anything up to
> ULONG_MAX currently. We can't tell at createblob time how
> the thing is going to be used, so can't have any kind
> of property specific limit unfortunately.

The failure I was seeing was for a gamma LUT, so a size limit alone
cannot solve the issue.


--
Earthling Michel DÃnzer | http://www.amd.com
Libre software enthusiast | Mesa and X developer