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/media/usb/pvrusb2/pvrusb2-hdw.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'drivers/media/usb/pvrusb2') diff --git a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c index 62ff1fa1c753..75c89b07e86a 100644 --- a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c +++ b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c @@ -2605,10 +2605,10 @@ struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf, return hdw; fail: if (hdw) { - del_timer_sync(&hdw->quiescent_timer); - del_timer_sync(&hdw->decoder_stabilization_timer); - del_timer_sync(&hdw->encoder_run_timer); - del_timer_sync(&hdw->encoder_wait_timer); + timer_shutdown_sync(&hdw->quiescent_timer); + timer_shutdown_sync(&hdw->decoder_stabilization_timer); + timer_shutdown_sync(&hdw->encoder_run_timer); + timer_shutdown_sync(&hdw->encoder_wait_timer); flush_work(&hdw->workpoll); v4l2_device_unregister(&hdw->v4l2_dev); usb_free_urb(hdw->ctl_read_urb); @@ -2668,10 +2668,10 @@ void pvr2_hdw_destroy(struct pvr2_hdw *hdw) if (!hdw) return; pvr2_trace(PVR2_TRACE_INIT,"pvr2_hdw_destroy: hdw=%p",hdw); flush_work(&hdw->workpoll); - del_timer_sync(&hdw->quiescent_timer); - del_timer_sync(&hdw->decoder_stabilization_timer); - del_timer_sync(&hdw->encoder_run_timer); - del_timer_sync(&hdw->encoder_wait_timer); + timer_shutdown_sync(&hdw->quiescent_timer); + timer_shutdown_sync(&hdw->decoder_stabilization_timer); + timer_shutdown_sync(&hdw->encoder_run_timer); + timer_shutdown_sync(&hdw->encoder_wait_timer); if (hdw->fw_buffer) { kfree(hdw->fw_buffer); hdw->fw_buffer = NULL; -- cgit v1.2.3