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>

3 files changed, 4 insertions, 4 deletions

diff --git a/drivers/usb/gadget/udc/m66592-udc.c b/drivers/usb/gadget/udc/m66592-udc.c
index 931e6362a13d..c7e421b449f3 100644
--- a/drivers/usb/gadget/udc/m66592-udc.c
+++ b/drivers/usb/gadget/udc/m66592-udc.c
@@ -1519,7 +1519,7 @@ static int m66592_remove(struct platform_device *pdev)
 
 	usb_del_gadget_udc(&m66592->gadget);
 
-	del_timer_sync(&m66592->timer);
+	timer_shutdown_sync(&m66592->timer);
 	iounmap(m66592->reg);
 	free_irq(platform_get_irq(pdev, 0), m66592);
 	m66592_free_request(&m66592->ep[0].ep, m66592->ep0_req);
diff --git a/drivers/usb/serial/garmin_gps.c b/drivers/usb/serial/garmin_gps.c
index f1a8d8343623..670e942fdaaa 100644
--- a/drivers/usb/serial/garmin_gps.c
+++ b/drivers/usb/serial/garmin_gps.c
@@ -1405,7 +1405,7 @@ static void garmin_port_remove(struct usb_serial_port *port)
 
 	usb_kill_anchored_urbs(&garmin_data_p->write_urbs);
 	usb_kill_urb(port->interrupt_in_urb);
-	del_timer_sync(&garmin_data_p->timer);
+	timer_shutdown_sync(&garmin_data_p->timer);
 	kfree(garmin_data_p);
 }
 
diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index 6b12bb4648b8..73370eaae0ab 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1725,8 +1725,8 @@ static void mos7840_port_remove(struct usb_serial_port *port)
 		/* Turn off LED */
 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
 
-		del_timer_sync(&mos7840_port->led_timer1);
-		del_timer_sync(&mos7840_port->led_timer2);
+		timer_shutdown_sync(&mos7840_port->led_timer1);
+		timer_shutdown_sync(&mos7840_port->led_timer2);
 
 		usb_kill_urb(mos7840_port->led_urb);
 		usb_free_urb(mos7840_port->led_urb);