wifi: mt76: mt7925: prevent NULL pointer dereference in mt7925_tx_check_aggr()

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

Fixes: 44eb173bdd4f ("wifi: mt76: mt7925: add link handling in mt7925_txwi_free")
Signed-off-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250904030649.655436-4-mingyen.hsieh@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
index 63e58c177d6567bd3890c782a81bd59b8d2c698e..33cd5e85a31d702b005934450b53d683beabf97a 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
@@ -846,11 +846,14 @@ 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;