[PATCH v2 6/6] drm: add drm_mode_atomic_commit event

[Steven Rostedt]

On Tue, 13 Feb 2024 16:50:31 +0100
Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer at amd.com> wrote:

> @@ -1503,6 +1504,24 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
>  		drm_mode_object_put(obj);
>  	}
>  
> +	if (trace_drm_mode_atomic_commit_enabled()) {
> +		struct drm_crtc_state *crtc_state;
> +		struct drm_crtc *crtc;
> +		int *crtcs;
> +		int i, num_crtcs;
> +
> +		crtcs = kcalloc(dev->mode_config.num_crtc, sizeof(int),
> +				GFP_KERNEL);

If the above allocation fails, this will cause a NULL kernel dereference.

-- Steve

> +
> +		num_crtcs = 0;
> +		for_each_new_crtc_in_state(state, crtc, crtc_state, i)
> +			crtcs[num_crtcs++] = drm_crtc_index(crtc);
> +
> +		trace_drm_mode_atomic_commit(file_priv, crtcs, num_crtcs, arg->flags);
> +
> +		kfree(crtcs);
> +	}
> +
>  	ret = prepare_signaling(dev, state, arg, file_priv, &fence_state,
>  				&num_fences);
>  	if (ret)