Re: [PATCH v6 1/3] media: v4l2-subdev: Verify arguments in v4l2_subdev_call()

[Sakari Ailus]

Hi Janusz,

On Wed, May 15, 2019 at 12:48:21AM +0200, Janusz Krzysztofik wrote:
> -static int check_crop(struct v4l2_subdev *sd, struct v4l2_subdev_crop *crop)
> +static inline int check_pad(struct v4l2_subdev *sd, __u32 pad)
>  {
> -	if (crop->which != V4L2_SUBDEV_FORMAT_TRY &&
> -	    crop->which != V4L2_SUBDEV_FORMAT_ACTIVE)
> +#if defined(CONFIG_MEDIA_CONTROLLER)
> +	if (sd->entity.num_pads && pad >= sd->entity.num_pads)

One more comment.

The num_pads doesn't really tell whether a given op is valid for a device.
Well, in this case it would have to be a bug in the driver, but those do
happen. How about checking for sd->entity.graph_obj.mdev instead? It's
non-NULL if the entity is registered with a media device, i.e. when these
callback functions are supposed to be called.

-- 
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx