[PATCH] media: rtl28xxu: fix SDR platform device leak

[Guangshuo Li]

rtl2832u_tuner_attach() registers an rtl2832_sdr platform device, but
if registration succeeds without a bound driver, it breaks out without
unregistering the device.

dev->platform_device_sdr is assigned only after a driver is bound, so
rtl28xxu_tuner_detach() cannot unregister the unbound device later.
This leaves the registered platform device and its associated resources
allocated.

Split the registration failure and driver binding checks. Unregister
the successfully registered platform device when no driver is bound
before leaving the switch.

The issue was identified by a static analysis tool I developed and
confirmed by manual review.

Fixes: a2f7f220df5e ("[media] rtl28xxu: switch SDR module to platform driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 drivers/media/usb/dvb-usb-v2/rtl28xxu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
index 487c6ab784ab..3603d0cf638b 100644
--- a/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
+++ b/drivers/media/usb/dvb-usb-v2/rtl28xxu.c
@@ -1391,8 +1391,12 @@ static int rtl2832u_tuner_attach(struct dvb_usb_adapter *adap)
 						     "rtl2832_sdr",
 						     PLATFORM_DEVID_AUTO,
 						     &pdata, sizeof(pdata));
-		if (IS_ERR(pdev) || pdev->dev.driver == NULL)
+		if (IS_ERR(pdev))
 			break;
+		if (!pdev->dev.driver) {
+			platform_device_unregister(pdev);
+			break;
+		}
 		dev->platform_device_sdr = pdev;
 		break;
 	default:
-- 
2.43.0