Re: [PATCH 2/2] Fix a NULL-ptr-deref bug in ath10k_usb_alloc_urb_from_pipe

From: Guenter Roeck <linux@roeck-us.net>
To: Kalle Valo <kvalo@codeaurora.org>
Cc: Hui Peng <benquike@gmail.com>,
	davem@davemloft.net, Mathias Payer <mathias.payer@nebelwelt.net>,
	ath10k@lists.infradead.org, linux-wireless@vger.kernel.org,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] Fix a NULL-ptr-deref bug in ath10k_usb_alloc_urb_from_pipe
Date: Fri, 18 Oct 2019 06:35:46 -0700	[thread overview]
Message-ID: <5e0e1760-07ee-efa1-1c33-3276dc81cc67@roeck-us.net> (raw)
In-Reply-To: <875zkmxz6f.fsf@kamboji.qca.qualcomm.com>

On 10/18/19 12:58 AM, Kalle Valo wrote:
> Guenter Roeck <linux@roeck-us.net> writes:
> 
>> On Sun, Sep 01, 2019 at 11:06:05AM +0300, Kalle Valo wrote:
>>> Guenter Roeck <linux@roeck-us.net> writes:
>>>
>>>> Hi,
>>>>
>>>> On Sat, Aug 03, 2019 at 08:31:01PM -0400, Hui Peng wrote:
>>>>> The `ar_usb` field of `ath10k_usb_pipe_usb_pipe` objects
>>>>> are initialized to point to the containing `ath10k_usb` object
>>>>> according to endpoint descriptors read from the device side, as shown
>>>>> below in `ath10k_usb_setup_pipe_resources`:
>>>>>
>>>>> for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
>>>>>          endpoint = &iface_desc->endpoint[i].desc;
>>>>>
>>>>>          // get the address from endpoint descriptor
>>>>>          pipe_num = ath10k_usb_get_logical_pipe_num(ar_usb,
>>>>>                                                  endpoint->bEndpointAddress,
>>>>>                                                  &urbcount);
>>>>>          ......
>>>>>          // select the pipe object
>>>>>          pipe = &ar_usb->pipes[pipe_num];
>>>>>
>>>>>          // initialize the ar_usb field
>>>>>          pipe->ar_usb = ar_usb;
>>>>> }
>>>>>
>>>>> The driver assumes that the addresses reported in endpoint
>>>>> descriptors from device side  to be complete. If a device is
>>>>> malicious and does not report complete addresses, it may trigger
>>>>> NULL-ptr-deref `ath10k_usb_alloc_urb_from_pipe` and
>>>>> `ath10k_usb_free_urb_to_pipe`.
>>>>>
>>>>> This patch fixes the bug by preventing potential NULL-ptr-deref.
>>>>>
>>>>> Signed-off-by: Hui Peng <benquike@gmail.com>
>>>>> Reported-by: Hui Peng <benquike@gmail.com>
>>>>> Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
>>>>
>>>> This patch fixes CVE-2019-15099, which has CVSS scores of 7.5 (CVSS 3.0)
>>>> and 7.8 (CVSS 2.0). Yet, I don't find it in the upstream kernel or in Linux
>>>> next.
>>>>
>>>> Is the patch going to be applied to the upstream kernel anytime soon ?
>>>
>>> Same answer as in patch 1:
>>>
>>> https://patchwork.kernel.org/patch/11074655/
>>>
>>
>> Sorry to bring this up again. The ath6k patch made it into the upstream
>> kernel, but the ath10k patch didn't. Did it get lost, or was there a
>> reason not to apply this patch ?
> 
> This patch had a build warning, you can see it from patchwork:
> 
> https://patchwork.kernel.org/patch/11074657/
> 
> Can someone fix it and resend the patch, please?
> 

Done.

Guenter