Hello Ryder Lee,
The patch 402a695b1ae6: "mt76: mt7615: fix CSA notification for DBDC"
from Feb 27, 2021, leads to the following static checker warning:
drivers/net/wireless/mediatek/mt76/mt7615/mcu.c:385 mt7615_mcu_rx_csa_notify()
error: undefined (user controlled) shift '(((1))) << (c->omac_idx)'
drivers/net/wireless/mediatek/mt76/mt7615/mcu.c
376 static void
377 mt7615_mcu_rx_csa_notify(struct mt7615_dev *dev, struct sk_buff *skb)
378 {
379 struct mt7615_phy *ext_phy = mt7615_ext_phy(dev);
380 struct mt76_phy *mphy = &dev->mt76.phy;
381 struct mt7615_mcu_csa_notify *c;
382
383 c = (struct mt7615_mcu_csa_notify *)skb->data;
^ ^^^^^^^^^
c is random data from the network
384
385 if (ext_phy && ext_phy->omac_mask & BIT_ULL(c->omac_idx))
^^^^^^^^^^^
Any value more than 61 will lead to undefined behavior. (shift wrapping
mostly).
386 mphy = dev->mt76.phy2;
387
388 ieee80211_iterate_active_interfaces_atomic(mphy->hw,
389 IEEE80211_IFACE_ITER_RESUME_ALL,
390 mt7615_mcu_csa_finish, mphy->hw);
391 }
regards,
dan carpenter
