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>

4 files changed, 4 insertions, 4 deletions

diff --git a/drivers/leds/trigger/ledtrig-activity.c b/drivers/leds/trigger/ledtrig-activity.c
index 30bc9df03636..33cbf8413658 100644
--- a/drivers/leds/trigger/ledtrig-activity.c
+++ b/drivers/leds/trigger/ledtrig-activity.c
@@ -208,7 +208,7 @@ static void activity_deactivate(struct led_classdev *led_cdev)
 {
 	struct activity_data *activity_data = led_get_trigger_data(led_cdev);
 
-	del_timer_sync(&activity_data->timer);
+	timer_shutdown_sync(&activity_data->timer);
 	kfree(activity_data);
 	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
 }
diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c
index 7fe0a05574d2..393b3ae832f4 100644
--- a/drivers/leds/trigger/ledtrig-heartbeat.c
+++ b/drivers/leds/trigger/ledtrig-heartbeat.c
@@ -151,7 +151,7 @@ static void heartbeat_trig_deactivate(struct led_classdev *led_cdev)
 	struct heartbeat_trig_data *heartbeat_data =
 		led_get_trigger_data(led_cdev);
 
-	del_timer_sync(&heartbeat_data->timer);
+	timer_shutdown_sync(&heartbeat_data->timer);
 	kfree(heartbeat_data);
 	clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
 }
diff --git a/drivers/leds/trigger/ledtrig-pattern.c b/drivers/leds/trigger/ledtrig-pattern.c
index 885ca63f383f..fadd87dbe993 100644
--- a/drivers/leds/trigger/ledtrig-pattern.c
+++ b/drivers/leds/trigger/ledtrig-pattern.c
@@ -430,7 +430,7 @@ static void pattern_trig_deactivate(struct led_classdev *led_cdev)
 	if (led_cdev->pattern_clear)
 		led_cdev->pattern_clear(led_cdev);
 
-	del_timer_sync(&data->timer);
+	timer_shutdown_sync(&data->timer);
 
 	led_set_brightness(led_cdev, LED_OFF);
 	kfree(data);
diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c
index 80635183fac8..f111fa7635e5 100644
--- a/drivers/leds/trigger/ledtrig-transient.c
+++ b/drivers/leds/trigger/ledtrig-transient.c
@@ -180,7 +180,7 @@ static void transient_trig_deactivate(struct led_classdev *led_cdev)
 {
 	struct transient_trig_data *transient_data = led_get_trigger_data(led_cdev);
 
-	del_timer_sync(&transient_data->timer);
+	timer_shutdown_sync(&transient_data->timer);
 	led_set_brightness_nosleep(led_cdev, transient_data->restore_state);
 	kfree(transient_data);
 }