[lvc-project] [PATCH v2] wifi: ath9k: avoid referencing uninit memory in ath9k_wmi_ctrl_rx

[Toke Høiland-Jørgensen]

Fedor Pchelkin <pchelkin at ispras.ru> writes:

> 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.
>
> Fixes: fb9987d0f748 ("ath9k_htc: Support for AR9271 chipset.")
> Reported-and-tested-by: syzbot+f2cb6e0ffdb961921e4d at syzkaller.appspotmail.com
> Signed-off-by: Fedor Pchelkin <pchelkin at ispras.ru>

Acked-by: Toke Høiland-Jørgensen <toke at toke.dk>