[PATCH 5.13 489/800] mt76: fix possible NULL pointer dereference in mt76_tx

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:42:58 EST


From: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>

[ Upstream commit d7400a2f3e295b8cee692c7a66e10f60015a3c37 ]

Even if this is not a real issue since mt76_tx is never run with wcid set
to NULL, fix a theoretical NULL pointer dereference in mt76_tx routine

Fixes: db9f11d3433f7 ("mt76: store wcid tx rate info in one u32 reduce locking")
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/mediatek/mt76/tx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/tx.c b/drivers/net/wireless/mediatek/mt76/tx.c
index 53ea8de82df0..441d06e30b1a 100644
--- a/drivers/net/wireless/mediatek/mt76/tx.c
+++ b/drivers/net/wireless/mediatek/mt76/tx.c
@@ -285,7 +285,7 @@ mt76_tx(struct mt76_phy *phy, struct ieee80211_sta *sta,
skb_set_queue_mapping(skb, qid);
}

- if (!(wcid->tx_info & MT_WCID_TX_INFO_SET))
+ if (wcid && !(wcid->tx_info & MT_WCID_TX_INFO_SET))
ieee80211_get_tx_rates(info->control.vif, sta, skb,
info->control.rates, 1);

--
2.30.2