wifi: mt76: mt7925: validate mlink in sta_hdr_trans_tlv()

Replace the dead wcid NULL check in mt7925_mcu_sta_hdr_trans_tlv() with
a WARN_ON_ONCE() guard on mlink before dereferencing mlink->wcid.

wcid is always derived from mlink, so mlink is the only meaningful
object to validate here.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Link: https://patch.msgid.link/20260306232238.2039675-9-sean.wang@kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
index 476aec8337a9fdb259cfac24918ab69376eec133..ba471341e8d0792e972d64ef8964d7e125950f4a 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
@@ -1082,11 +1082,11 @@ mt7925_mcu_sta_hdr_trans_tlv(struct sk_buff *skb,
        else
                hdr_trans->from_ds = true;
 
-       wcid = &mlink->wcid;
-
-       if (!wcid)
+       if (WARN_ON_ONCE(!mlink))
                return;
 
+       wcid = &mlink->wcid;
+
        hdr_trans->dis_rx_hdr_tran = !test_bit(MT_WCID_FLAG_HDR_TRANS, &wcid->flags);
        if (test_bit(MT_WCID_FLAG_4ADDR, &wcid->flags)) {
                hdr_trans->to_ds = true;