[PATCH stable 4.9 16/21] media: dvb_frontend: be sure to init dvb_frontend_handle_ioctl() return code

[Florian Fainelli]

From: Mauro Carvalho Chehab <mche...@s-opensource.com>

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: sta...@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mche...@s-opensource.com>
Tested-by: Daniel Scheller <d.schel...@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mche...@s-opensource.com>
Signed-off-by: Florian Fainelli <f.faine...@gmail.com>
---
 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 a9ae9e509205..6f9ee78a1870 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;
        }
 
-- 
2.17.1