[PATCH] media: cxusb: Initialize medion after checking intf

[Edward Adam Davis <eadavis@qq.com>]

dvb_usb_device_exit() is entered because the number of alternate setting
is less than 2. Check the USB interface in advance to avoid unnecessary
dvb device initialization and exit.

Reported-by: syzbot+0dcc341ee61fc9e4032f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0dcc341ee61fc9e4032f
Tested-by: syzbot+0dcc341ee61fc9e4032f@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 drivers/media/usb/dvb-usb/cxusb.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/media/usb/dvb-usb/cxusb.c b/drivers/media/usb/dvb-usb/cxusb.c
index f44529b40989..df86ae7106c1 100644
--- a/drivers/media/usb/dvb-usb/cxusb.c
+++ b/drivers/media/usb/dvb-usb/cxusb.c
@@ -1601,13 +1601,9 @@ static int cxusb_probe(struct usb_interface *intf,
 	int ret;
 
 	/* Medion 95700 */
-	if (!dvb_usb_device_init(intf, &cxusb_medion_properties,
+	if (cxusb_medion_check_intf(intf) &&
+	    !dvb_usb_device_init(intf, &cxusb_medion_properties,
 				 THIS_MODULE, &dvbdev, adapter_nr)) {
-		if (!cxusb_medion_check_intf(intf)) {
-			ret = -ENODEV;
-			goto ret_uninit;
-		}
-
 		_cxusb_power_ctrl(dvbdev, 1);
 		ret = cxusb_medion_set_mode(dvbdev, false);
 		if (ret)
-- 
2.43.0