Description

In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: avoid referencing uninit memory in ath9k_wmi_ctrl_rx For the reasons also described in commit b383e8abed41 ("wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg()"), ath9k_htc_rx_msg() should validate pkt_len before accessing the SKB. For example, the obtained SKB may have been badly constructed with pkt_len = 8. In this case, the SKB can only contain a valid htc_frame_hdr but after being processed in ath9k_htc_rx_msg() and passed to ath9k_wmi_ctrl_rx() endpoint RX handler, it is expected to have a WMI command header which should be located inside its data payload. Implement sanity checking inside ath9k_wmi_ctrl_rx(). Otherwise, uninit memory can be referenced. Tested on Qualcomm Atheros Communications AR9271 802.11n . Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

References 9

• git.kernel.org https://git.kernel.org/stable/c/0bc12e41af4e3ae1f0efecc377f0514459df0707
• git.kernel.org https://git.kernel.org/stable/c/250efb4d3f5b32a115ea6bf25437ba44a1b3c04f
• git.kernel.org https://git.kernel.org/stable/c/28259ce4f1f1f9ab37fa817756c89098213d2fc0
• git.kernel.org https://git.kernel.org/stable/c/75acec91aeaa07375cd5f418069e61b16d39bbad
• git.kernel.org https://git.kernel.org/stable/c/8ed572e52714593b209e3aa352406aff84481179
• git.kernel.org https://git.kernel.org/stable/c/90e3c10177573b8662ac9858abd9bf731d5d98e0
• git.kernel.org https://git.kernel.org/stable/c/ad5425e70789c29b93acafb5bb4629e4eb908296
• git.kernel.org https://git.kernel.org/stable/c/d1c2ff2bd84c3692c9df267a2b991ce92bfca8ef
• git.kernel.org https://git.kernel.org/stable/c/f24292e827088bba8de7158501ac25a59b064953

Remediation