[PATCHv2 5/6] v4l2-ctrls: check for REQUIRES_REQUESTS flag

[Hans Verkuil]

Attempts to get/try/set controls that require requests
without actually specifying a request are now rejected.

Signed-off-by: Hans Verkuil <hverkuil-ci...@xs4all.nl>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c 
b/drivers/media/v4l2-core/v4l2-ctrls.c
index 99308dac2daa..25f80f0eba69 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -3150,6 +3150,9 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler 
*hdl,
                ctrl = ref->ctrl;
                if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)
                        return -EINVAL;
+               if ((ctrl->flags & V4L2_CTRL_FLAG_REQUIRES_REQUESTS) &&
+                   !hdl->req_obj.req)
+                       return -EACCES;
 
                if (ctrl->cluster[0]->ncontrols > 1)
                        have_clusters = true;
-- 
2.20.1