Commit 0dc68cab authored Mar 21, 2018 by Kieran Bingham Committed by Mauro Carvalho Chehab Jun 05, 2018

media: uvcvideo: Prevent setting unavailable flags



The addition of an extra operation to use the GET_INFO command
overwrites all existing flags from the uvc_ctrls table. This includes
setting all controls as supporting GET_MIN, GET_MAX, GET_RES, and
GET_DEF regardless of whether they do or not.

Move the initialisation of these control capabilities directly to the
uvc_ctrl_fill_xu_info() call where they were originally located in that
use case, and ensure that the new functionality in uvc_ctrl_get_flags()
will only set flags based on their reported capability from the GET_INFO
call.

Fixes: 859086ae ("media: uvcvideo: Apply flags from device to actual properties")

Cc: stable@vger.kernel.org
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Tested-by: Guennadi Liakhovetski <guennadi.liakhovetski@intel.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

parent a00031c1

drivers/media/usb/uvc/uvc_ctrl.c

+9 −8

Original line number	Diff line number	Diff line
		@@ -1607,9 +1607,7 @@ static int uvc_ctrl_get_flags(struct uvc_device *dev,
		ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id, dev->intfnum,
		info->selector, data, 1);
		if (!ret)
		info->flags = UVC_CTRL_FLAG_GET_MIN \| UVC_CTRL_FLAG_GET_MAX
		\| UVC_CTRL_FLAG_GET_RES \| UVC_CTRL_FLAG_GET_DEF
		\| (data[0] & UVC_CONTROL_CAP_GET ?
		info->flags \|= (data[0] & UVC_CONTROL_CAP_GET ?
		UVC_CTRL_FLAG_GET_CUR : 0)
		\| (data[0] & UVC_CONTROL_CAP_SET ?
		UVC_CTRL_FLAG_SET_CUR : 0)
		@@ -1689,6 +1687,9 @@ static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,

		info->size = le16_to_cpup((__le16 *)data);

		info->flags = UVC_CTRL_FLAG_GET_MIN \| UVC_CTRL_FLAG_GET_MAX
		\| UVC_CTRL_FLAG_GET_RES \| UVC_CTRL_FLAG_GET_DEF;

		ret = uvc_ctrl_get_flags(dev, ctrl, info);
		if (ret < 0) {
		uvc_trace(UVC_TRACE_CONTROL,