media: v4l2-ctrls: v4l2_ctrl_g/s_ctrl*(): don't continue when WARN_ON

If the v4l2_ctrl_g_ctrl*() or __v4l2_ctrl_s_ctrl*() functions
are called for the wrong control type then they call WARN_ON
since that is a driver error. But they still continue, potentially
overwriting data. Change this to return an error (s_ctrl) or 0
(g_ctrl), just to be safe.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/v4l2-core/v4l2-ctrls.c

@@ -3799,7 +3799,8 @@ s32 v4l2_ctrl_g_ctrl(struct v4l2_ctrl *ctrl)
 	struct v4l2_ext_control c;
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(!ctrl->is_int);
+	if (WARN_ON(!ctrl->is_int))
+		return 0;
 	c.value = 0;
 	get_ctrl(ctrl, &c);
 	return c.value;
@@ -3811,7 +3812,8 @@ s64 v4l2_ctrl_g_ctrl_int64(struct v4l2_ctrl *ctrl)
 	struct v4l2_ext_control c;
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(ctrl->is_ptr || ctrl->type != V4L2_CTRL_TYPE_INTEGER64);
+	if (WARN_ON(ctrl->is_ptr || ctrl->type != V4L2_CTRL_TYPE_INTEGER64))
+		return 0;
 	c.value64 = 0;
 	get_ctrl(ctrl, &c);
 	return c.value64;
@@ -4220,7 +4222,8 @@ int __v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val)
 	lockdep_assert_held(ctrl->handler->lock);
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(!ctrl->is_int);
+	if (WARN_ON(!ctrl->is_int))
+		return -EINVAL;
 	ctrl->val = val;
 	return set_ctrl(NULL, ctrl, 0);
 }
@@ -4231,7 +4234,8 @@ int __v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val)
 	lockdep_assert_held(ctrl->handler->lock);
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(ctrl->is_ptr || ctrl->type != V4L2_CTRL_TYPE_INTEGER64);
+	if (WARN_ON(ctrl->is_ptr || ctrl->type != V4L2_CTRL_TYPE_INTEGER64))
+		return -EINVAL;
 	*ctrl->p_new.p_s64 = val;
 	return set_ctrl(NULL, ctrl, 0);
 }
@@ -4242,7 +4246,8 @@ int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
 	lockdep_assert_held(ctrl->handler->lock);
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(ctrl->type != V4L2_CTRL_TYPE_STRING);
+	if (WARN_ON(ctrl->type != V4L2_CTRL_TYPE_STRING))
+		return -EINVAL;
 	strscpy(ctrl->p_new.p_char, s, ctrl->maximum + 1);
 	return set_ctrl(NULL, ctrl, 0);
 }
@@ -4254,7 +4259,8 @@ int __v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
 	lockdep_assert_held(ctrl->handler->lock);
 
 	/* It's a driver bug if this happens. */
-	WARN_ON(ctrl->type != V4L2_CTRL_TYPE_AREA);
+	if (WARN_ON(ctrl->type != V4L2_CTRL_TYPE_AREA))
+		return -EINVAL;
 	*ctrl->p_new.p_area = *area;
 	return set_ctrl(NULL, ctrl, 0);
 }