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: Thu, 17 Oct 2019 21:05:30 -0700	[thread overview]
Message-ID: <20191018040530.GA28167@roeck-us.net> (raw)
In-Reply-To: <87ftlgqw42.fsf@kamboji.qca.qualcomm.com>

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 ?

Thanks,
Guenter