[PATCH 1/3] drm/amdgpu: Add NULL ptr check for non userq fences

[Christian König]

Am 20.11.24 um 10:26 schrieb Arunpravin Paneer Selvam:
> We are observing a NULL value in the non userq fences,
> thus added a NULL pointer check just to avoid the
> NULL pointer dereference crash.
>
> v2: Moved the NULL check above the non userq check.
>
> Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> index 6157a540c929..76f7babd7a54 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c
> @@ -815,6 +815,9 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data,
>   			struct amdgpu_userq_fence *userq_fence;
>   			u32 index;
>   
> +			if (!fences[i])
> +				continue;

That should never ever happen in the first place.

All fences in the array either come from some reservation object or 
drm_syncobj. If any of those are NULL then there is a bug somewhere else.

Regards,
Christian.

> +
>   			userq_fence = to_amdgpu_userq_fence(fences[i]);
>   			if (!userq_fence) {
>   				/*