[PATCH 5.10 0/2] ath9k_htc: fix NULL pointer dereferences at ath9k_htc_rxep() and ath9k_htc_tx_get_packet()
Syzkaller reports NULL pointer dereference issues at ath9k_htc_rxep() and ath9k_htc_tx_get_packet() in 5.10 stable releases. The problems have been fixed by the following patch series which can be cleanly applied to the 5.10 branch.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp
commit b0ec7e55fce65f125bd1d7f02e2dc4de62abee34 upstream.
syzbot is reporting lockdep warning followed by kernel panic at ath9k_htc_rxep() [1], for ath9k_htc_rxep() depends on ath9k_rx_init() being already completed.
Since ath9k_htc_rxep() is set by ath9k_htc_connect_svc(WMI_BEACON_SVC) from ath9k_init_htc_services(), it is possible that ath9k_htc_rxep() is called via timer interrupt before ath9k_rx_init() from ath9k_init_device() is called.
Since we can't call ath9k_init_device() before ath9k_init_htc_services(), let's hold ath9k_htc_rxep() no-op until ath9k_rx_init() completes.
Link: https://syzkaller.appspot.com/bug?extid=4d2d56175b934b9a7bf9 [1] Reported-by: syzbot syzbot+4d2d56175b934b9a7bf9@syzkaller.appspotmail.com Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Tested-by: syzbot syzbot+4d2d56175b934b9a7bf9@syzkaller.appspotmail.com Signed-off-by: Kalle Valo quic_kvalo@quicinc.com Link: https://lore.kernel.org/r/2b88f416-b2cb-7a18-d688-951e6dc3fe92@i-love.sakura... Signed-off-by: Fedor Pchelkin pchelkin@ispras.ru --- drivers/net/wireless/ath/ath9k/htc.h | 1 + drivers/net/wireless/ath/ath9k/htc_drv_txrx.c | 8 ++++++++ 2 files changed, 9 insertions(+)
diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h index 0a1634238e67..4f71e962279a 100644 --- a/drivers/net/wireless/ath/ath9k/htc.h +++ b/drivers/net/wireless/ath/ath9k/htc.h @@ -281,6 +281,7 @@ struct ath9k_htc_rxbuf { struct ath9k_htc_rx { struct list_head rxbuf; spinlock_t rxbuflock; + bool initialized; };
#define ATH9K_HTC_TX_CLEANUP_INTERVAL 50 /* ms */ diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c index 30ddf333e04d..592034ea4b68 100644 --- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c +++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c @@ -1133,6 +1133,10 @@ void ath9k_htc_rxep(void *drv_priv, struct sk_buff *skb, struct ath9k_htc_rxbuf *rxbuf = NULL, *tmp_buf = NULL; unsigned long flags;
+ /* Check if ath9k_rx_init() completed. */ + if (!data_race(priv->rx.initialized)) + goto err; + spin_lock_irqsave(&priv->rx.rxbuflock, flags); list_for_each_entry(tmp_buf, &priv->rx.rxbuf, list) { if (!tmp_buf->in_process) { @@ -1188,6 +1192,10 @@ int ath9k_rx_init(struct ath9k_htc_priv *priv) list_add_tail(&rxbuf->list, &priv->rx.rxbuf); }
+ /* Allow ath9k_htc_rxep() to operate. */ + smp_wmb(); + priv->rx.initialized = true; + return 0;
err:
From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp
commit 8b3046abc99eefe11438090bcc4ec3a3994b55d0 upstream.
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... Signed-off-by: Fedor Pchelkin pchelkin@ispras.ru --- drivers/net/wireless/ath/ath9k/htc.h | 1 + drivers/net/wireless/ath/ath9k/htc_drv_txrx.c | 5 +++++ drivers/net/wireless/ath/ath9k/wmi.c | 4 ++++ 3 files changed, 10 insertions(+)
diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h index 4f71e962279a..6b45e63fae4b 100644 --- a/drivers/net/wireless/ath/ath9k/htc.h +++ b/drivers/net/wireless/ath/ath9k/htc.h @@ -306,6 +306,7 @@ struct ath9k_htc_tx { DECLARE_BITMAP(tx_slot, MAX_TX_BUF_NUM); struct timer_list cleanup_timer; spinlock_t tx_lock; + bool initialized; };
struct ath9k_htc_tx_ctl { diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c index 592034ea4b68..43a743ec9d9e 100644 --- a/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c +++ b/drivers/net/wireless/ath/ath9k/htc_drv_txrx.c @@ -808,6 +808,11 @@ 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_vo_queue); 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; }
diff --git a/drivers/net/wireless/ath/ath9k/wmi.c b/drivers/net/wireless/ath/ath9k/wmi.c index fe29ad4b9023..f315c54bd3ac 100644 --- a/drivers/net/wireless/ath/ath9k/wmi.c +++ b/drivers/net/wireless/ath/ath9k/wmi.c @@ -169,6 +169,10 @@ void ath9k_wmi_event_tasklet(struct tasklet_struct *t) &wmi->drv_priv->fatal_work); break; case WMI_TXSTATUS_EVENTID: + /* Check if ath9k_tx_init() completed. */ + if (!data_race(priv->tx.initialized)) + break; + spin_lock_bh(&priv->tx.tx_lock); if (priv->tx.flags & ATH9K_HTC_OP_TX_DRAIN) { spin_unlock_bh(&priv->tx.tx_lock);
linux-stable-mirror@lists.linaro.org
-
Fedor Pchelkin