← CVE Intelligence

CVE-2026-68194

wifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses PUBLISHED

Description (CNA)

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7921: drop TXRX_NOTIFY on non-mmio buses PKT_TYPE_TXRX_NOTIFY is an mmio-only event, but mt7921_rx_check() and mt7921_queue_rx_skb() dispatch it to mt7921_mac_tx_free() on every bus. mt7921_mac_tx_free() cleans the DMA tx queues with mt76_queue_tx_cleanup(), which calls queue_ops->tx_cleanup(). Only the mmio queue ops implement that callback; on USB and SDIO it is NULL, so a TXRX_NOTIFY there calls a NULL pointer in the RX worker: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Call Trace: mt7921_mac_tx_free+0x64/0x310 [mt7921_common] mt7921_rx_check+0x5f/0xf0 [mt7921_common] mt76u_rx_worker+0x1b9/0x620 [mt76_usb] Drop the event on non-mmio buses via mt76_is_mmio(), as in commit 5683e1488aa9 ("wifi: mt76: connac: do not check WED status for non-mmio devices").

Affected (CNA)

Vendor / productVersions
Linux / Linuxaffected 48fab5bbef4092d925ab3214773ad12e68807223 before 7003a2cbddd7917933c1f169c7874cfa6ab852c3; affected 48fab5bbef4092d925ab3214773ad12e68807223 before ef2ee5f820c3ef87643b51e960c20b4a14d8336b; affected 48fab5bbef4092d925ab3214773ad12e68807223 before ecf995b828191829ba4a87169bccabcbeb5c9c32; affected 48fab5bbef4092d925ab3214773ad12e68807223 before 263816e92e8d66c81c98ccab2b5d2191ed08ec71; affected 48fab5bbef4092d925ab3214773ad12e68807223 before 24475d2ddc8d8dfd82f4d2be0d951401f86911a6; affected 48fab5bbef4092d925ab3214773ad12e68807223 before da4082e91acabc1498611ed8ccc53f0610baefc6
Linux / Linuxaffected 5.16; unaffected 0 before 5.16; unaffected 6.1.183 through 6.1.*; unaffected 6.6.148 through 6.6.*; unaffected 6.12.101 through 6.12.*; unaffected 6.18.42 through 6.18.*; unaffected 7.1.6 through 7.1.*; unaffected 7.2 through *

CWE

No CWE identifiers supplied.

References