public-mirrors/linux
1
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-05-24 10:39:52 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

ath9k_htc: fix NULL pointer dereference at ath9k_htc_tx_get_packet()

Browse source 
syzbot is reporting lockdep warning at ath9k_wmi_event_tasklet() followed
by kernel panic at get_htc_epid_queue() from ath9k_htc_tx_get_packet() from
ath9k_htc_txstatus() [1], for ath9k_wmi_event_tasklet(WMI_TXSTATUS_EVENTID)
depends on spin_lock_init() from ath9k_init_priv() being already completed.

Since ath9k_wmi_event_tasklet() is set by ath9k_init_wmi() from
ath9k_htc_probe_device(), it is possible that ath9k_wmi_event_tasklet() is
called via tasklet interrupt before spin_lock_init() from ath9k_init_priv()
 from ath9k_init_device() from ath9k_htc_probe_device() is called.

Let's hold ath9k_wmi_event_tasklet(WMI_TXSTATUS_EVENTID) no-op until
ath9k_tx_init() completes.

Link: https://syzkaller.appspot.com/bug?extid=31d54c60c5b254d6f75b [1]
Reported-by: syzbot <syzbot+31d54c60c5b254d6f75b@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+31d54c60c5b254d6f75b@syzkaller.appspotmail.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/77b76ac8-2bee-6444-d26c-8c30858b8daa@i-love.sakura.ne.jp
This commit is contained in:
Tetsuo Handa 2021-09-21 22:06:26 +09:00 • committed by Kalle Valo
parent b0ec7e55fc
commit 8b3046abc9
3 changed files with 10 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
drivers/net/wireless/ath/ath9k/htc.h
View file

@ -306,6 +306,7 @@ struct ath9k_htc_tx {
DECLARE_BITMAP(tx_slot, MAX_TX_BUF_NUM); DECLARE_BITMAP(tx_slot, MAX_TX_BUF_NUM);
struct timer_list cleanup_timer; struct timer_list cleanup_timer;
spinlock_t tx_lock; spinlock_t tx_lock;
bool initialized;
}; };
struct ath9k_htc_tx_ctl { struct ath9k_htc_tx_ctl {

5
drivers/net/wireless/ath/ath9k/htc_drv_txrx.c
View file

@ -813,6 +813,11 @@ int ath9k_tx_init(struct ath9k_htc_priv *priv)
skb_queue_head_init(&priv->tx.data_vi_queue); skb_queue_head_init(&priv->tx.data_vi_queue);
skb_queue_head_init(&priv->tx.data_vo_queue); skb_queue_head_init(&priv->tx.data_vo_queue);
skb_queue_head_init(&priv->tx.tx_failed); skb_queue_head_init(&priv->tx.tx_failed);
/* Allow ath9k_wmi_event_tasklet(WMI_TXSTATUS_EVENTID) to operate. */
smp_wmb();
priv->tx.initialized = true;
return 0; return 0;
} }

4
drivers/net/wireless/ath/ath9k/wmi.c
View file

@ -169,6 +169,10 @@ void ath9k_wmi_event_tasklet(struct tasklet_struct *t)
&wmi->drv_priv->fatal_work); &wmi->drv_priv->fatal_work);
break; break;
case WMI_TXSTATUS_EVENTID: case WMI_TXSTATUS_EVENTID:
/* Check if ath9k_tx_init() completed. */
if (!data_race(priv->tx.initialized))
break;
spin_lock_bh(&priv->tx.tx_lock); spin_lock_bh(&priv->tx.tx_lock);
if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) { if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) {
spin_unlock_bh(&priv->tx.tx_lock); spin_unlock_bh(&priv->tx.tx_lock);