Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
> This is a static checker fix, not something I have tested. The issue
> is that on the second iteration through the loop, we jump forward by
> le32_to_cpu(auth_req->length) bytes. The problem is that if the length
> is more than "buflen" then we end up with a negative "buflen". A
> negative buflen is type promoted to a high positive value and the loop
> continues but it's accessing beyond the end of the buffer.
>
> I believe the "auth_req->length" comes from the firmware and if the
> firmware is malicious or buggy, you're already toasted so the impact of
> this bug is probably not very severe.
>
> Fixes: 030645aceb3d ("rndis_wlan: handle 802.11 indications from device")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>
> diff --git a/drivers/net/wireless/rndis_wlan.c b/drivers/net/wireless/rndis_wlan.c
> index 9935bd09db1f..d4947e3a909e 100644
> --- a/drivers/net/wireless/rndis_wlan.c
> +++ b/drivers/net/wireless/rndis_wlan.c
> @@ -2928,6 +2928,8 @@ static void rndis_wlan_auth_indication(struct usbnet *usbdev,
>
> while (buflen >= sizeof(*auth_req)) {
> auth_req = (void *)buf;
> + if (buflen < le32_to_cpu(auth_req->length))
> + return;
> type = "unknown";
> flags = le32_to_cpu(auth_req->flags);
> pairwise_error = false;
Patch applied to wireless-drivers-next.git, thanks.
ae636fb15548 rndis_wlan: potential buffer overflow in rndis_wlan_auth_indication()
--
https://patchwork.kernel.org/patch/10448061/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
