[PATCH 5.3 20/48] Input: ff-memless - kill timer in destroy()

[Greg Kroah-Hartman]

From: Oliver Neukum <oneukum@xxxxxxxx>

commit fa3a5a1880c91bb92594ad42dfe9eedad7996b86 upstream.

No timer must be left running when the device goes away.

Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Reported-and-tested-by: syzbot+b6c55daa701fc389e286@xxxxxxxxxxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/1573726121.17351.3.camel@xxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/input/ff-memless.c |    9 +++++++++
 1 file changed, 9 insertions(+)

--- a/drivers/input/ff-memless.c
+++ b/drivers/input/ff-memless.c
@@ -489,6 +489,15 @@ static void ml_ff_destroy(struct ff_devi
 {
 	struct ml_device *ml = ff->private;
 
+	/*
+	 * Even though we stop all playing effects when tearing down
+	 * an input device (via input_device_flush() that calls into
+	 * input_ff_flush() that stops and erases all effects), we
+	 * do not actually stop the timer, and therefore we should
+	 * do it here.
+	 */
+	del_timer_sync(&ml->timer);
+
 	kfree(ml->private);
 }