| Message ID | nycvar.YFH.7.76.2202152037000.11721@cbobk.fhfr.pm |
|---|---|
| State | New |
| Headers | show |
| Series | rtw89: fix RCU usage in rtw89_core_txq_push() | expand |
Jiri Kosina <jkosina@suse.cz> wrote: > From: Jiri Kosina <jkosina@suse.cz> > Subject: [PATCH] rtw89: fix RCU usage in rtw89_core_txq_push() > > ieee80211_tx_h_select_key() is performing a series of RCU dereferences, > but rtw89_core_txq_push() is calling it (via ieee80211_tx_dequeue_ni()) > without RCU read-side lock held; fix that. > > This addresses the splat below. > > ============================= > WARNING: suspicious RCU usage > 5.17.0-rc4-00003-gccad664b7f14 #3 Tainted: G E > ----------------------------- > net/mac80211/tx.c:593 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > rcu_scheduler_active = 2, debug_locks = 1 > 2 locks held by kworker/u33:0/184: > #0: ffff9c0b14811d38 ((wq_completion)rtw89_tx_wq){+.+.}-{0:0}, at: process_one_work+0x258/0x660 > #1: ffffb97380cf3e78 ((work_completion)(&rtwdev->txq_work)){+.+.}-{0:0}, at: process_one_work+0x258/0x660 > > stack backtrace: > CPU: 8 PID: 184 Comm: kworker/u33:0 Tainted: G E 5.17.0-rc4-00003-gccad664b7f14 #3 473b49ab0e7c2d6af2900c756bfd04efd7a9de13 > Hardware name: LENOVO 20UJS2B905/20UJS2B905, BIOS R1CET63W(1.32 ) 04/09/2021 > Workqueue: rtw89_tx_wq rtw89_core_txq_work [rtw89_core] > Call Trace: > <TASK> > dump_stack_lvl+0x58/0x71 > ieee80211_tx_h_select_key+0x2c0/0x530 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365] > ieee80211_tx_dequeue+0x1a7/0x1260 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365] > rtw89_core_txq_work+0x1a6/0x420 [rtw89_core b39ba493f2e517ad75e0f8187ecc24edf58bbbea] > process_one_work+0x2d8/0x660 > worker_thread+0x39/0x3e0 > ? process_one_work+0x660/0x660 > kthread+0xe5/0x110 > ? kthread_complete_and_exit+0x20/0x20 > ret_from_fork+0x22/0x30 > </TASK> > > ============================= > WARNING: suspicious RCU usage > 5.17.0-rc4-00003-gccad664b7f14 #3 Tainted: G E > ----------------------------- > net/mac80211/tx.c:607 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > rcu_scheduler_active = 2, debug_locks = 1 > 2 locks held by kworker/u33:0/184: > #0: ffff9c0b14811d38 ((wq_completion)rtw89_tx_wq){+.+.}-{0:0}, at: process_one_work+0x258/0x660 > #1: ffffb97380cf3e78 ((work_completion)(&rtwdev->txq_work)){+.+.}-{0:0}, at: process_one_work+0x258/0x660 > > stack backtrace: > CPU: 8 PID: 184 Comm: kworker/u33:0 Tainted: G E 5.17.0-rc4-00003-gccad664b7f14 #3 473b49ab0e7c2d6af2900c756bfd04efd7a9de13 > Hardware name: LENOVO 20UJS2B905/20UJS2B905, BIOS R1CET63W(1.32 ) 04/09/2021 > Workqueue: rtw89_tx_wq rtw89_core_txq_work [rtw89_core] > Call Trace: > <TASK> > dump_stack_lvl+0x58/0x71 > ieee80211_tx_h_select_key+0x464/0x530 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365] > ieee80211_tx_dequeue+0x1a7/0x1260 [mac80211 911c23e2351c0ae60b597a67b1204a5ea955e365] > rtw89_core_txq_work+0x1a6/0x420 [rtw89_core b39ba493f2e517ad75e0f8187ecc24edf58bbbea] > process_one_work+0x2d8/0x660 > worker_thread+0x39/0x3e0 > ? process_one_work+0x660/0x660 > kthread+0xe5/0x110 > ? kthread_complete_and_exit+0x20/0x20 > ret_from_fork+0x22/0x30 > </TASK> > > Signed-off-by: Jiri Kosina <jkosina@suse.cz> > Acked-by: Ping-Ke Shih <pkshih@realtek.com> Patch applied to wireless-next.git, thanks. f3d825a35920 rtw89: fix RCU usage in rtw89_core_txq_push()
diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wireless/realtek/rtw89/core.c index a0737eea9f81..9632e7f218dd 100644 --- a/drivers/net/wireless/realtek/rtw89/core.c +++ b/drivers/net/wireless/realtek/rtw89/core.c @@ -1509,11 +1509,12 @@ static void rtw89_core_txq_push(struct rtw89_dev *rtwdev, unsigned long i; int ret; + rcu_read_lock(); for (i = 0; i < frame_cnt; i++) { skb = ieee80211_tx_dequeue_ni(rtwdev->hw, txq); if (!skb) { rtw89_debug(rtwdev, RTW89_DBG_TXRX, "dequeue a NULL skb\n"); - return; + goto out; } rtw89_core_txq_check_agg(rtwdev, rtwtxq, skb); ret = rtw89_core_tx_write(rtwdev, vif, sta, skb, NULL); @@ -1523,6 +1524,8 @@ static void rtw89_core_txq_push(struct rtw89_dev *rtwdev, break; } } +out: + rcu_read_unlock(); } static u32 rtw89_check_and_reclaim_tx_resource(struct rtw89_dev *rtwdev, u8 tid)