linux/drivers/isdn
Steven Rostedt (Google) 292a089d78 treewide: Convert del_timer*() to timer_shutdown*()
Due to several bugs caused by timers being re-armed after they are
shutdown and just before they are freed, a new state of timers was added
called "shutdown".  After a timer is set to this state, then it can no
longer be re-armed.

The following script was run to find all the trivial locations where
del_timer() or del_timer_sync() is called in the same function that the
object holding the timer is freed.  It also ignores any locations where
the timer->function is modified between the del_timer*() and the free(),
as that is not considered a "trivial" case.

This was created by using a coccinelle script and the following
commands:

    $ cat timer.cocci
    @@
    expression ptr, slab;
    identifier timer, rfield;
    @@
    (
    -       del_timer(&ptr->timer);
    +       timer_shutdown(&ptr->timer);
    |
    -       del_timer_sync(&ptr->timer);
    +       timer_shutdown_sync(&ptr->timer);
    )
      ... when strict
          when != ptr->timer
    (
            kfree_rcu(ptr, rfield);
    |
            kmem_cache_free(slab, ptr);
    |
            kfree(ptr);
    )

    $ spatch timer.cocci . > /tmp/t.patch
    $ patch -p1 < /tmp/t.patch

Link: https://lore.kernel.org/lkml/20221123201306.823305113@linutronix.de/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-25 13:38:09 -08:00
..
capi isdn: move from strlcpy with unused retval to strscpy 2022-08-22 17:54:03 -07:00
hardware mISDN: hfcmulti: don't call dev_kfree_skb/kfree_skb() under spin_lock_irqsave() 2022-12-13 19:24:52 -08:00
mISDN treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile isdn: capi: dead code removal 2019-12-11 09:12:38 +01:00