[PATCH 4.9 113/191] media: dvb_frontend: be sure to init dvb_frontend_handle_ioctl() return code
From: Sasha Levin
Date:  Mon Jun 29 2020 - 15:27:33 EST
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")
Cc: stable@xxxxxxxxxxxxxxx
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: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/media/dvb-core/dvb_frontend.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index a9ae9e5092050..6f9ee78a18703 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -2113,7 +2113,7 @@ static int dvb_frontend_handle_ioctl(struct file *file,
 	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__);
 
@@ -2148,6 +2148,7 @@ static int dvb_frontend_handle_ioctl(struct file *file,
 			}
 		}
 		kfree(tvp);
+		err = 0;
 		break;
 	}
 	case FE_GET_PROPERTY: {
@@ -2198,6 +2199,7 @@ static int dvb_frontend_handle_ioctl(struct file *file,
 			return -EFAULT;
 		}
 		kfree(tvp);
+		err = 0;
 		break;
 	}
 
-- 
2.25.1