[PATCH] media: stkwebcam: Use usb_get_dev() for the reference count of udev

[Cai Huoqing <caihuoqing@baidu.com>]

Use usb_get_dev() to increment the reference count of the usb device
structure in order to avoid releasing the structure while it is still in
use. And use usb_put_dev() to decrement the reference count and thus,
when it will be equal to 0 the structure will be released.

Reported-by: Salah Triki <salah.triki@gmail.com>
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
---
 drivers/media/usb/stkwebcam/stk-webcam.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c
index 0e231e576dc3..b54a23c6842e 100644
--- a/drivers/media/usb/stkwebcam/stk-webcam.c
+++ b/drivers/media/usb/stkwebcam/stk-webcam.c
@@ -1234,6 +1234,7 @@ static void stk_v4l_dev_release(struct video_device *vd)
 	if (dev->sio_bufs != NULL || dev->isobufs != NULL)
 		pr_err("We are leaking memory\n");
 	usb_put_intf(dev->interface);
+	usb_put_dev(dev->udev);
 }
 
 static const struct video_device stk_v4l_data = {
@@ -1309,7 +1310,7 @@ static int stk_camera_probe(struct usb_interface *interface,
 	init_waitqueue_head(&dev->wait_frame);
 	dev->first_init = 1; /* webcam LED management */
 
-	dev->udev = udev;
+	dev->udev = usb_get_dev(udev);
 	dev->interface = interface;
 	usb_get_intf(interface);
 
-- 
2.25.1