[PATCH] wifi: mt76: scan: Fix 'mlink' dereferenced before IS_ERR_OR_NULL check

[jiangfeng]

From: Feng Jiang <jiangfeng@xxxxxxxxxx>

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://lore.kernel.org/r/202504011739.HvUKtUUe-lkp@xxxxxxxxx/
Fixes: 3ba20af886d1 ("wifi: mt76: scan: set vif offchannel link for scanning/roc")
Signed-off-by: Feng Jiang <jiangfeng@xxxxxxxxxx>
---
 drivers/net/wireless/mediatek/mt76/channel.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/channel.c b/drivers/net/wireless/mediatek/mt76/channel.c
index e7b839e74290..cc2d888e3f17 100644
--- a/drivers/net/wireless/mediatek/mt76/channel.c
+++ b/drivers/net/wireless/mediatek/mt76/channel.c
@@ -302,11 +302,13 @@ void mt76_put_vif_phy_link(struct mt76_phy *phy, struct ieee80211_vif *vif,
 			   struct mt76_vif_link *mlink)
 {
 	struct mt76_dev *dev = phy->dev;
-	struct mt76_vif_data *mvif = mlink->mvif;
+	struct mt76_vif_data *mvif;
 
 	if (IS_ERR_OR_NULL(mlink) || !mlink->offchannel)
 		return;
 
+	mvif = mlink->mvif;
+
 	rcu_assign_pointer(mvif->offchannel_link, NULL);
 	dev->drv->vif_link_remove(phy, vif, &vif->bss_conf, mlink);
 	kfree(mlink);
-- 
2.25.1