Re: [PATCH v6 01/17] media: v4l2-ioctl: check_ext_ctrls: Fix multiclass V4L2_CTRL_WHICH_DEF_VAL

[Hans Verkuil <hverkuil-cisco@xs4all.nl>]

Hi Ricardo,

On 17/03/2021 17:44, Ricardo Ribalda wrote:
> Drivers that do not use the ctrl-framework use this function instead.
> 
> - Do not check for multiple classes when getting the DEF_VAL.
> 
> Fixes v4l2-compliance:
> Control ioctls (Input 0):
> 		fail: v4l2-test-controls.cpp(813): doioctl(node, VIDIOC_G_EXT_CTRLS, &ctrls)
> 	test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL

Can you merge patches 1-4 into a single patch? It's really one big fix since
this code was never updated when new 'which' values were added. So keeping it
together is, for once, actually preferred.

You can add my:

Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

after these 4 patches are merged. It looks much nicer now.

Regards,

	Hans

> 
> Cc: stable@vger.kernel.org
> Fixes: 6fa6f831f095 ("media: v4l2-ctrls: add core request support")
> Suggested-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/media/v4l2-core/v4l2-ioctl.c | 47 ++++++++++++++++------------
>  1 file changed, 27 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 31d1342e61e8..403f957a1012 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -908,7 +908,7 @@ static void v4l_print_default(const void *arg, bool write_only)
>  	pr_cont("driver-specific ioctl\n");
>  }
>  
> -static int check_ext_ctrls(struct v4l2_ext_controls *c, int allow_priv)
> +static bool check_ext_ctrls(struct v4l2_ext_controls *c, unsigned long ioctl)
>  {
>  	__u32 i;
>  
> @@ -917,23 +917,30 @@ static int check_ext_ctrls(struct v4l2_ext_controls *c, int allow_priv)
>  	for (i = 0; i < c->count; i++)
>  		c->controls[i].reserved2[0] = 0;
>  
> -	/* V4L2_CID_PRIVATE_BASE cannot be used as control class
> -	   when using extended controls.
> -	   Only when passed in through VIDIOC_G_CTRL and VIDIOC_S_CTRL
> -	   is it allowed for backwards compatibility.
> -	 */
> -	if (!allow_priv && c->which == V4L2_CID_PRIVATE_BASE)
> -		return 0;
> -	if (!c->which)
> -		return 1;
> +	switch (c->which) {
> +	case V4L2_CID_PRIVATE_BASE:
> +		/*
> +		 * V4L2_CID_PRIVATE_BASE cannot be used as control class
> +		 * when using extended controls.
> +		 * Only when passed in through VIDIOC_G_CTRL and VIDIOC_S_CTRL
> +		 * is it allowed for backwards compatibility.
> +		 */
> +		if (ioctl == VIDIOC_G_CTRL || ioctl == VIDIOC_S_CROP)
> +			return false;
> +		break;
> +	case V4L2_CTRL_WHICH_DEF_VAL:
> +	case V4L2_CTRL_WHICH_CUR_VAL:
> +		return true;
> +	}
> +
>  	/* Check that all controls are from the same control class. */
>  	for (i = 0; i < c->count; i++) {
>  		if (V4L2_CTRL_ID2WHICH(c->controls[i].id) != c->which) {
>  			c->error_idx = i;
> -			return 0;
> +			return false;
>  		}
>  	}
> -	return 1;
> +	return true;
>  }
>  
>  static int check_fmt(struct file *file, enum v4l2_buf_type type)
> @@ -2229,7 +2236,7 @@ static int v4l_g_ctrl(const struct v4l2_ioctl_ops *ops,
>  	ctrls.controls = &ctrl;
>  	ctrl.id = p->id;
>  	ctrl.value = p->value;
> -	if (check_ext_ctrls(&ctrls, 1)) {
> +	if (check_ext_ctrls(&ctrls, VIDIOC_G_CTRL)) {
>  		int ret = ops->vidioc_g_ext_ctrls(file, fh, &ctrls);
>  
>  		if (ret == 0)
> @@ -2263,7 +2270,7 @@ static int v4l_s_ctrl(const struct v4l2_ioctl_ops *ops,
>  	ctrls.controls = &ctrl;
>  	ctrl.id = p->id;
>  	ctrl.value = p->value;
> -	if (check_ext_ctrls(&ctrls, 1))
> +	if (check_ext_ctrls(&ctrls, VIDIOC_S_CTRL))
>  		return ops->vidioc_s_ext_ctrls(file, fh, &ctrls);
>  	return -EINVAL;
>  }
> @@ -2285,8 +2292,8 @@ static int v4l_g_ext_ctrls(const struct v4l2_ioctl_ops *ops,
>  					vfd, vfd->v4l2_dev->mdev, p);
>  	if (ops->vidioc_g_ext_ctrls == NULL)
>  		return -ENOTTY;
> -	return check_ext_ctrls(p, 0) ? ops->vidioc_g_ext_ctrls(file, fh, p) :
> -					-EINVAL;
> +	return check_ext_ctrls(p, VIDIOC_G_EXT_CTRLS) ?
> +				ops->vidioc_g_ext_ctrls(file, fh, p) : -EINVAL;
>  }
>  
>  static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> @@ -2306,8 +2313,8 @@ static int v4l_s_ext_ctrls(const struct v4l2_ioctl_ops *ops,
>  					vfd, vfd->v4l2_dev->mdev, p);
>  	if (ops->vidioc_s_ext_ctrls == NULL)
>  		return -ENOTTY;
> -	return check_ext_ctrls(p, 0) ? ops->vidioc_s_ext_ctrls(file, fh, p) :
> -					-EINVAL;
> +	return check_ext_ctrls(p, VIDIOC_S_EXT_CTRLS) ?
> +				ops->vidioc_s_ext_ctrls(file, fh, p) : -EINVAL;
>  }
>  
>  static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops,
> @@ -2327,8 +2334,8 @@ static int v4l_try_ext_ctrls(const struct v4l2_ioctl_ops *ops,
>  					  vfd, vfd->v4l2_dev->mdev, p);
>  	if (ops->vidioc_try_ext_ctrls == NULL)
>  		return -ENOTTY;
> -	return check_ext_ctrls(p, 0) ? ops->vidioc_try_ext_ctrls(file, fh, p) :
> -					-EINVAL;
> +	return check_ext_ctrls(p, VIDIOC_TRY_EXT_CTRLS) ?
> +			ops->vidioc_try_ext_ctrls(file, fh, p) : -EINVAL;
>  }
>  
>  /*
>