In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7603: initialize global station WCID mt7603 uses a drive

In the Linux kernel, the following vulnerability has been resolved:

wifi: mt76: mt7603: initialize global station WCID

mt7603 uses a driver-private global station WCID for frames that have
neither a station nor a vif, including frames injected through a monitor
interface. Unlike the core global WCID initialized by
mt76_register_device(), this WCID is published without ever being passed
to mt76_wcid_init().

Since commit 0335c034e726 ("wifi: mt76: fix race condition related to
checking tx queue fill status"), mt76_tx() queues every such frame on the
WCID's tx_pending or tx_offchannel queue and links its tx_list. The first
injected frame therefore reaches __skb_queue_tail() with an uninitialized
sk_buff_head and dereferences a NULL prev pointer.

Initialize the WCID before publishing it.

The fix was tested on an MT7603 PCIe device. Three wildcard probe requests
were injected through a monitor interface. The hardware queue head and tail
advanced from 0 to 3 and a second radio captured the third request over the
air. No oops or reset occurred. After restoring AP mode, a 150 MB transfer
also completed without a reset.