[PATCH] drm/prime: Fix drm_gem_prime_mmap() stack use

[Noralf Trønnes]

Den 22.11.2018 10.06, skrev Daniel Vetter:
> On Wed, Nov 21, 2018 at 07:02:15PM +0100, Noralf Trønnes wrote:
>>     drivers/gpu/drm/drm_prime.c: In function 'drm_gem_prime_mmap':
>>>> drivers/gpu/drm/drm_prime.c:688:1: warning: the frame size of 1592 bytes is larger than 1024 bytes [-Wframe-larger-than=]
>> Fix by allocating on the heap.
>>
>> Fixes: 7698799f9554 ("drm/prime: Add drm_gem_prime_mmap()")
>> Reported-by: kbuild test robot <lkp at intel.com>
>> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
>> Cc: Christian König <christian.koenig at amd.com>
>> Signed-off-by: Noralf Trønnes <noralf at tronnes.org>
> Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>


Thanks Daniel, applied to drm-misc-next.


Noralf.


>
>> ---
>>   drivers/gpu/drm/drm_prime.c | 31 ++++++++++++++++++++-----------
>>   1 file changed, 20 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
>> index 5737cb8c6f03..231e3f6d5f41 100644
>> --- a/drivers/gpu/drm/drm_prime.c
>> +++ b/drivers/gpu/drm/drm_prime.c
>> @@ -663,24 +663,33 @@ EXPORT_SYMBOL(drm_gem_prime_handle_to_fd);
>>    */
>>   int drm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
>>   {
>> -	/* Used by drm_gem_mmap() to lookup the GEM object */
>> -	struct drm_file priv = {
>> -		.minor = obj->dev->primary,
>> -	};
>> -	struct file fil = {
>> -		.private_data = &priv,
>> -	};
>> +	struct drm_file *priv;
>> +	struct file *fil;
>>   	int ret;
>>   
>> -	ret = drm_vma_node_allow(&obj->vma_node, &priv);
>> +	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
>> +	fil = kzalloc(sizeof(*fil), GFP_KERNEL);
>> +	if (!priv || !fil) {
>> +		ret = -ENOMEM;
>> +		goto out;
>> +	}
>> +
>> +	/* Used by drm_gem_mmap() to lookup the GEM object */
>> +	priv->minor = obj->dev->primary;
>> +	fil->private_data = priv;
>> +
>> +	ret = drm_vma_node_allow(&obj->vma_node, priv);
>>   	if (ret)
>> -		return ret;
>> +		goto out;
>>   
>>   	vma->vm_pgoff += drm_vma_node_start(&obj->vma_node);
>>   
>> -	ret = obj->dev->driver->fops->mmap(&fil, vma);
>> +	ret = obj->dev->driver->fops->mmap(fil, vma);
>>   
>> -	drm_vma_node_revoke(&obj->vma_node, &priv);
>> +	drm_vma_node_revoke(&obj->vma_node, priv);
>> +out:
>> +	kfree(priv);
>> +	kfree(fil);
>>   
>>   	return ret;
>>   }
>> -- 
>> 2.15.1
>>