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) <rostedt@goodmis.org>
Acked-by: Pavel Machek <pavel@ucw.cz> [ LED ]
Acked-by: Kalle Valo <kvalo@kernel.org> [ wireless ]
Acked-by: Paolo Abeni <pabeni@redhat.com> [ networking ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 8 insertions, 8 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c
index f9f18ff451ea..7ea2631b8069 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/btcoex.c
@@ -394,7 +394,7 @@ void brcmf_btcoex_detach(struct brcmf_cfg80211_info *cfg)
 
 	if (cfg->btcoex->timer_on) {
 		cfg->btcoex->timer_on = false;
-		del_timer_sync(&cfg->btcoex->timer);
+		timer_shutdown_sync(&cfg->btcoex->timer);
 	}
 
 	cancel_work_sync(&cfg->btcoex->work);
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
index 6d6c12999645..48e7376a5fea 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
@@ -371,7 +371,7 @@ void iwl_dbg_tlv_del_timers(struct iwl_trans *trans)
 	struct iwl_dbg_tlv_timer_node *node, *tmp;
 
 	list_for_each_entry_safe(node, tmp, timer_list, list) {
-		del_timer_sync(&node->timer);
+		timer_shutdown_sync(&node->timer);
 		list_del(&node->list);
 		kfree(node);
 	}
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 6c9c5d6e7783..69634fb82a9b 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2835,7 +2835,7 @@ int iwl_mvm_sta_rx_agg(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
 
 		/* synchronize all rx queues so we can safely delete */
 		iwl_mvm_free_reorder(mvm, baid_data);
-		del_timer_sync(&baid_data->session_timer);
+		timer_shutdown_sync(&baid_data->session_timer);
 		RCU_INIT_POINTER(mvm->baid_map[baid], NULL);
 		kfree_rcu(baid_data, rcu_head);
 		IWL_DEBUG_HT(mvm, "BAID %d is free\n", baid);
diff --git a/drivers/net/wireless/intersil/hostap/hostap_ap.c b/drivers/net/wireless/intersil/hostap/hostap_ap.c
index 462ccc7d7d1a..9b546a71e7a2 100644
--- a/drivers/net/wireless/intersil/hostap/hostap_ap.c
+++ b/drivers/net/wireless/intersil/hostap/hostap_ap.c
@@ -135,7 +135,7 @@ static void ap_free_sta(struct ap_data *ap, struct sta_info *sta)
 
 	if (!sta->ap)
 		kfree(sta->u.sta.challenge);
-	del_timer_sync(&sta->timer);
+	timer_shutdown_sync(&sta->timer);
 #endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */
 
 	kfree(sta);
diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index da2e6557e684..ea22a08e6c08 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c
@@ -123,7 +123,7 @@ static int mwifiex_unregister(struct mwifiex_adapter *adapter)
 	if (adapter->if_ops.cleanup_if)
 		adapter->if_ops.cleanup_if(adapter);
 
-	del_timer_sync(&adapter->cmd_timer);
+	timer_shutdown_sync(&adapter->cmd_timer);
 
 	/* Free private structures */
 	for (i = 0; i < adapter->priv_num; i++) {
diff --git a/drivers/net/wireless/microchip/wilc1000/hif.c b/drivers/net/wireless/microchip/wilc1000/hif.c
index 67df8221b5ae..5adc69d5bcae 100644
--- a/drivers/net/wireless/microchip/wilc1000/hif.c
+++ b/drivers/net/wireless/microchip/wilc1000/hif.c
@@ -1531,10 +1531,10 @@ int wilc_deinit(struct wilc_vif *vif)
 
 	mutex_lock(&vif->wilc->deinit_lock);
 
-	del_timer_sync(&hif_drv->scan_timer);
-	del_timer_sync(&hif_drv->connect_timer);
+	timer_shutdown_sync(&hif_drv->scan_timer);
+	timer_shutdown_sync(&hif_drv->connect_timer);
 	del_timer_sync(&vif->periodic_rssi);
-	del_timer_sync(&hif_drv->remain_on_ch_timer);
+	timer_shutdown_sync(&hif_drv->remain_on_ch_timer);
 
 	if (hif_drv->usr_scan_req.scan_result) {
 		hif_drv->usr_scan_req.scan_result(SCAN_EVENT_ABORTED, NULL,