CVE-2026-68193

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

wifi: mt76: mt7925: drop TXRX_NOTIFY on non-mmio buses

PKTTYPETXRXNOTIFY is an mmio-only event, but mt7925rxcheck() and mt7925queuerxskb() dispatch it to mt7925mactxfree() on every bus. mt7925mactxfree() cleans the DMA tx queues with mt76queuetxcleanup(), which calls queueops->txcleanup(). Only the mmio queue ops implement that callback; on USB it is NULL, so a TXRXNOTIFY there calls a NULL pointer in the RX worker:

BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Call Trace: mt7925mactxfree+0x58/0x350 [mt7925common] mt7925rxcheck+0xe2/0x130 [mt7925common] mt76urxworker+0x1b9/0x620 [mt76usb]

Drop the event on non-mmio buses via mt76ismmio(), as in commit 5683e1488aa9 ("wifi: mt76: connac: do not check WED status for non-mmio devices").