From 292a089d78d3e2f7944e60bb897c977785a321e3 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Tue, 20 Dec 2022 13:45:19 -0500 Subject: 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) Acked-by: Pavel Machek [ LED ] Acked-by: Kalle Valo [ wireless ] Acked-by: Paolo Abeni [ networking ] Signed-off-by: Linus Torvalds --- drivers/nfc/pn533/pn533.c | 2 +- drivers/nfc/pn533/uart.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/nfc') diff --git a/drivers/nfc/pn533/pn533.c b/drivers/nfc/pn533/pn533.c index f0cac1900552..b19c39dcfbd9 100644 --- a/drivers/nfc/pn533/pn533.c +++ b/drivers/nfc/pn533/pn533.c @@ -2792,7 +2792,7 @@ void pn53x_common_clean(struct pn533 *priv) struct pn533_cmd *cmd, *n; /* delete the timer before cleanup the worker */ - del_timer_sync(&priv->listen_timer); + timer_shutdown_sync(&priv->listen_timer); flush_delayed_work(&priv->poll_work); destroy_workqueue(priv->wq); diff --git a/drivers/nfc/pn533/uart.c b/drivers/nfc/pn533/uart.c index 07596bf5f7d6..a556acdb947b 100644 --- a/drivers/nfc/pn533/uart.c +++ b/drivers/nfc/pn533/uart.c @@ -310,7 +310,7 @@ static void pn532_uart_remove(struct serdev_device *serdev) pn53x_unregister_nfc(pn532->priv); serdev_device_close(serdev); pn53x_common_clean(pn532->priv); - del_timer_sync(&pn532->cmd_timeout); + timer_shutdown_sync(&pn532->cmd_timeout); kfree_skb(pn532->recv_skb); kfree(pn532); } -- cgit v1.2.3