Pavel Emelyanov wrote:

Deleting a timer with del_timer doesn't guarantee, that the
timer function is not running at the moment of deletion. Thus
in the xt_hashlimit case we can get into a ticklish situation
when the htable_gc rearms the timer back and we'll actually
delete an entry with a pending timer.

Fix it with using del_timer_sync().

AFAIK del_timer_sync checks for the timer to be pending by
itself, so I remove the check.

Also applied, thanks.