From: Johan Hovold <johan@kernel.org>
Date: Thu, 21 Sep 2017 08:40:18 +0000 (-0300)
Subject: cx231xx-cards: fix NULL-deref on missing association descriptor
X-Git-Tag: v4.9.66~57
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=38c043d26c97a04332df960200a389bc4141ff21;p=platform%2Fkernel%2Flinux-amlogic.git

cx231xx-cards: fix NULL-deref on missing association descriptor

commit 6c3b047fa2d2286d5e438bcb470c7b1a49f415f6 upstream.

Make sure to check that we actually have an Interface Association
Descriptor before dereferencing it during probe to avoid dereferencing a
NULL-pointer.

Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/media/usb/cx231xx/cx231xx-cards.c b/drivers/media/usb/cx231xx/cx231xx-cards.c
index be9e3335dcb7..921cf1edb3b1 100644
--- a/drivers/media/usb/cx231xx/cx231xx-cards.c
+++ b/drivers/media/usb/cx231xx/cx231xx-cards.c
@@ -1622,7 +1622,7 @@ static int cx231xx_usb_probe(struct usb_interface *interface,
 	nr = dev->devno;
 
 	assoc_desc = udev->actconfig->intf_assoc[0];
-	if (assoc_desc->bFirstInterface != ifnum) {
+	if (!assoc_desc || assoc_desc->bFirstInterface != ifnum) {
 		dev_err(d, "Not found matching IAD interface\n");
 		retval = -ENODEV;
 		goto err_if;