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/isdn/mISDN/l1oip_core.c | 4 ++-- drivers/isdn/mISDN/timerdev.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/isdn/mISDN') diff --git a/drivers/isdn/mISDN/l1oip_core.c b/drivers/isdn/mISDN/l1oip_core.c index c24771336f61..f010b35a0531 100644 --- a/drivers/isdn/mISDN/l1oip_core.c +++ b/drivers/isdn/mISDN/l1oip_core.c @@ -1236,8 +1236,8 @@ release_card(struct l1oip *hc) hc->shutdown = true; - del_timer_sync(&hc->keep_tl); - del_timer_sync(&hc->timeout_tl); + timer_shutdown_sync(&hc->keep_tl); + timer_shutdown_sync(&hc->timeout_tl); cancel_work_sync(&hc->workq); diff --git a/drivers/isdn/mISDN/timerdev.c b/drivers/isdn/mISDN/timerdev.c index abdf36ac3bee..83d6b484d3c6 100644 --- a/drivers/isdn/mISDN/timerdev.c +++ b/drivers/isdn/mISDN/timerdev.c @@ -74,7 +74,7 @@ mISDN_close(struct inode *ino, struct file *filep) while (!list_empty(list)) { timer = list_first_entry(list, struct mISDNtimer, list); spin_unlock_irq(&dev->lock); - del_timer_sync(&timer->tl); + timer_shutdown_sync(&timer->tl); spin_lock_irq(&dev->lock); /* it might have been moved to ->expired */ list_del(&timer->list); @@ -204,7 +204,7 @@ misdn_del_timer(struct mISDNtimerdev *dev, int id) list_del_init(&timer->list); timer->id = -1; spin_unlock_irq(&dev->lock); - del_timer_sync(&timer->tl); + timer_shutdown_sync(&timer->tl); kfree(timer); return id; } -- cgit v1.2.3