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From:   Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
To:     Fedor Pchelkin <pchelkin@ispras.ru>, Kalle Vallo <kvalo@kernel.org>
Cc:     Fedor Pchelkin <pchelkin@ispras.ru>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Senthil Balasubramanian <senthilkumar@atheros.com>,
        "John W. Linville" <linville@tuxdriver.com>,
        Vasanthakumar Thiagarajan <vasanth@atheros.com>,
        Sujith <Sujith.Manoharan@atheros.com>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Alexey Khoroshilov <khoroshilov@ispras.ru>,
        lvc-project@linuxtesting.org,
        syzbot+f2cb6e0ffdb961921e4d@syzkaller.appspotmail.com
Subject: Re: [PATCH v2] wifi: ath9k: avoid referencing uninit memory in
 ath9k_wmi_ctrl_rx
In-Reply-To: <20230424183348.111355-1-pchelkin@ispras.ru>
References: <20230424183348.111355-1-pchelkin@ispras.ru>
Date:   Tue, 25 Apr 2023 13:14:43 +0200
Message-ID: <87sfcojjrw.fsf@toke.dk>
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Fedor Pchelkin <pchelkin@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 =3D 8. In this case, the SKB can only contain a valid htc_frame_h=
dr
> 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.=20
>
> 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@syzkaller.appspotmail=
.com
> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>

Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen <toke@toke.dk>