[PATCH 3.16 042/366] media: rc: oops in ir_timer_keyup after device unplug

Ben Hutchings
2018-10-14T23:37:23Z

From: Sean Young <sean@mess.org>

commit 8d4068810d9926250dd2435719a080b889eb44c3 upstream.

If there is IR in the raw kfifo when ir_raw_event_unregister() is called,
then kthread_stop() causes ir_raw_event_thread to be scheduled, decode
some scancodes and re-arm timer_keyup. The timer_keyup then fires when
the rc device is long gone.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
[bwh: Backported to 3.16:
- There's no timer_repeat to move
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -1427,13 +1427,13 @@ void rc_unregister_device(struct rc_dev
if (!dev)
return;

- del_timer_sync(&dev->timer_keyup);
-
clear_bit(dev->devno, ir_core_dev_number);

if (dev->driver_type == RC_DRIVER_IR_RAW)
ir_raw_event_unregister(dev);

+ del_timer_sync(&dev->timer_keyup);
+
/* Freeing the table should also call the stop callback */
ir_free_table(&dev->rc_map);
IR_dprintk(1, "Freed keycode table\n");