media: dvbdev: Fix memory leak in dvb_media_device_free()

commit bf9a40ae8d722f281a2721779595d6df1c33a0bf upstream.

dvb_media_device_free() is leaking memory. Free `dvbdev->adapter->conn`
before setting it to NULL, as documented in include/media/media-device.h:
"The media_entity instance itself must be freed explicitly by the driver
if required."

Link: https://syzkaller.appspot.com/bug?id=9bbe4b842c98f0ed05c5eed77a226e9de33bf298
Link: https://lore.kernel.org/linux-media/20201211083039.521617-1-yepeilin.cs@gmail.com
Cc: stable@vger.kernel.org
Fixes: 0230d60e4661 ("[media] dvbdev: Add RF connector if needed")
Reported-by: syzbot+7f09440acc069a0d38ac@syzkaller.appspotmail.com
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/media/dvb-core/dvbdev.c b/drivers/media/dvb-core/dvbdev.c
index a1cc1c1e5318299bf1d82f7e931f6ee7590d9961..fb1284051d0547244545056187e92205e9a7d773 100644 (file)
--- a/drivers/media/dvb-core/dvbdev.c
+++ b/drivers/media/dvb-core/dvbdev.c
@@ -216,6 +216,7 @@ static void dvb_media_device_free(struct dvb_device *dvbdev)
 
        if (dvbdev->adapter->conn) {
                media_device_unregister_entity(dvbdev->adapter->conn);
+               kfree(dvbdev->adapter->conn);
                dvbdev->adapter->conn = NULL;
                kfree(dvbdev->adapter->conn_pads);
                dvbdev->adapter->conn_pads = NULL;