[PATCH 4.15 150/202] media: dvb_frontend: be sure to init dvb_frontend_handle_ioctl() return code

[Greg Kroah-Hartman]

4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>

commit a9cb97c3e628902e37583d8a40bb28cf76522cf1 upstream.

As smatch warned:
	drivers/media/dvb-core/dvb_frontend.c:2468 dvb_frontend_handle_ioctl() error: uninitialized symbol 'err'.

The ioctl handler actually got a regression here: before changeset
d73dcf0cdb95 ("media: dvb_frontend: cleanup ioctl handling logic"),
the code used to return -EOPNOTSUPP if an ioctl handler was not
implemented on a driver. After the change, it may return a random
value.

Fixes: d73dcf0cdb95 ("media: dvb_frontend: cleanup ioctl handling logic")
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Tested-by: Daniel Scheller <d.scheller@xxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/media/dvb-core/dvb_frontend.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -2110,7 +2110,7 @@ static int dvb_frontend_handle_ioctl(str
 	struct dvb_frontend *fe = dvbdev->priv;
 	struct dvb_frontend_private *fepriv = fe->frontend_priv;
 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
-	int i, err;
+	int i, err = -EOPNOTSUPP;
 
 	dev_dbg(fe->dvb->device, "%s:\n", __func__);
 
@@ -2145,6 +2145,7 @@ static int dvb_frontend_handle_ioctl(str
 			}
 		}
 		kfree(tvp);
+		err = 0;
 		break;
 	}
 	case FE_GET_PROPERTY: {
@@ -2196,6 +2197,7 @@ static int dvb_frontend_handle_ioctl(str
 			return -EFAULT;
 		}
 		kfree(tvp);
+		err = 0;
 		break;
 	}