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 --- net/802/garp.c | 2 +- net/802/mrp.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'net/802') diff --git a/net/802/garp.c b/net/802/garp.c index 77aac2763835..ab24b21fbb49 100644 --- a/net/802/garp.c +++ b/net/802/garp.c @@ -618,7 +618,7 @@ void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl /* Delete timer and generate a final TRANSMIT_PDU event to flush out * all pending messages before the applicant is gone. */ - del_timer_sync(&app->join_timer); + timer_shutdown_sync(&app->join_timer); spin_lock_bh(&app->lock); garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU); diff --git a/net/802/mrp.c b/net/802/mrp.c index 66fcbf23b486..eafc21ecc287 100644 --- a/net/802/mrp.c +++ b/net/802/mrp.c @@ -911,8 +911,8 @@ void mrp_uninit_applicant(struct net_device *dev, struct mrp_application *appl) /* Delete timer and generate a final TX event to flush out * all pending messages before the applicant is gone. */ - del_timer_sync(&app->join_timer); - del_timer_sync(&app->periodic_timer); + timer_shutdown_sync(&app->join_timer); + timer_shutdown_sync(&app->periodic_timer); spin_lock_bh(&app->lock); mrp_mad_event(app, MRP_EVENT_TX); -- cgit v1.2.3