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 --- sound/i2c/other/ak4117.c | 2 +- sound/synth/emux/emux.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'sound') diff --git a/sound/i2c/other/ak4117.c b/sound/i2c/other/ak4117.c index 1bc43e927d82..640501bb3ca6 100644 --- a/sound/i2c/other/ak4117.c +++ b/sound/i2c/other/ak4117.c @@ -47,7 +47,7 @@ static void reg_dump(struct ak4117 *ak4117) static void snd_ak4117_free(struct ak4117 *chip) { - del_timer_sync(&chip->timer); + timer_shutdown_sync(&chip->timer); kfree(chip); } diff --git a/sound/synth/emux/emux.c b/sound/synth/emux/emux.c index a870759d179e..0006c3ddb51d 100644 --- a/sound/synth/emux/emux.c +++ b/sound/synth/emux/emux.c @@ -129,7 +129,7 @@ int snd_emux_free(struct snd_emux *emu) if (! emu) return -EINVAL; - del_timer_sync(&emu->tlist); + timer_shutdown_sync(&emu->tlist); snd_emux_proc_free(emu); snd_emux_delete_virmidi(emu); -- cgit v1.2.3