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 --- fs/ext4/super.c | 2 +- fs/nilfs2/segment.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'fs') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 16a343e8047d..260c1b3e3ef2 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1225,7 +1225,7 @@ static void ext4_put_super(struct super_block *sb) } ext4_es_unregister_shrinker(sbi); - del_timer_sync(&sbi->s_err_report); + timer_shutdown_sync(&sbi->s_err_report); ext4_release_system_zone(sb); ext4_mb_release(sb); ext4_ext_release(sb); diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index 3335ef352915..76c3bd88b858 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2752,7 +2752,7 @@ static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) down_write(&nilfs->ns_segctor_sem); - del_timer_sync(&sci->sc_timer); + timer_shutdown_sync(&sci->sc_timer); kfree(sci); } -- cgit v1.2.3