[PATCH] drm/amdkfd: Integer overflows in ioctl

Felix Kuehling felix.kuehling at amd.com
Wed Apr 25 16:05:40 UTC 2018

On 2018-04-25 05:21 AM, Dan Carpenter wrote:
> On Tue, Apr 24, 2018 at 02:58:10PM -0400, Felix Kuehling wrote:
>> Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com>
>> We could probably add a sanity check for n_devices to avoid user mode
>> causing excessive memory allocations in the kernel. There is no good
>> reason for this to be bigger than the number of GPUs in the system. The
>> maximum number of GPUs supported due to device minor limit in DRM is 128.
> 128 is sort of a magic number.  Is there a MAX_GPU define or something?
Actually, looking at drm_minor_alloc in drm_file.c, the maximum is only
64 GPUs. It's just a magic number in the code. There is no #define or
enum for this.


> regards,
> dan carpenter

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