[PATCH 3/4] wifi: mt76: mt7925: prevent NULL pointer dereference in mt7925_tx_check_aggr()

[Mingyen Hsieh]

From: Ming Yen Hsieh <mingyen.hsieh at mediatek.com>

Move the NULL check for 'sta' before dereferencing it to prevent a
possible crash.

Signed-off-by: Ming Yen Hsieh <mingyen.hsieh at mediatek.com>
---
 drivers/net/wireless/mediatek/mt76/mt7925/mac.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
index 122aa6e9070a..ff9f628ba005 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
@@ -845,11 +845,14 @@ static void mt7925_tx_check_aggr(struct ieee80211_sta *sta, struct sk_buff *skb,
 	bool is_8023;
 	u16 fc, tid;
 
+	if (!sta)
+		return;
+
 	link_sta = rcu_dereference(sta->link[wcid->link_id]);
 	if (!link_sta)
 		return;
 
-	if (!sta || !(link_sta->ht_cap.ht_supported || link_sta->he_cap.has_he))
+	if (!(link_sta->ht_cap.ht_supported || link_sta->he_cap.has_he))
 		return;
 
 	tid = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
-- 
2.34.1