Re: [PATCH v3] wifi: ath9k: hif_usb: clean up skbs if ath9k_hif_usb_rx_stream() fails

[Toke Høiland-Jørgensen]

Fedor Pchelkin <pchelkin@xxxxxxxxx> writes:

> Syzkaller detected a memory leak of skbs in ath9k_hif_usb_rx_stream().
> While processing skbs in ath9k_hif_usb_rx_stream(), the already allocated
> skbs in skb_pool are not freed if ath9k_hif_usb_rx_stream() fails. If we
> have an incorrect pkt_len or pkt_tag, the input skb is considered invalid
> and dropped. All the associated packets already in skb_pool should be
> dropped and freed. Added a comment describing this issue.
>
> The patch also makes remain_skb NULL after being processed so that it
> cannot be referenced after potential free. The initialization of hif_dev
> fields which are associated with remain_skb (rx_remain_len,
> rx_transfer_len and rx_pad_len) is moved after a new remain_skb is
> allocated. 
>
> Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
>
> Fixes: 6ce708f54cc8 ("ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream")
> Fixes: 44b23b488d44 ("ath9k: hif_usb: Reduce indent 1 column")
> Reported-by: syzbot+e9632e3eb038d93d6bc6@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
> Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>

Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxx>