The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6c3b047fa2d2286d5e438bcb470c7b1a49f415f6 Mon Sep 17 00:00:00 2001
From: Johan Hovold johan@kernel.org Date: Thu, 21 Sep 2017 05:40:18 -0300 Subject: [PATCH] [media] cx231xx-cards: fix NULL-deref on missing association descriptor
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")
Cc: stable stable@vger.kernel.org # 2.6.30 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
diff --git a/drivers/media/usb/cx231xx/cx231xx-cards.c b/drivers/media/usb/cx231xx/cx231xx-cards.c index e0daa9b6c2a0..9b742d569fb5 100644 --- a/drivers/media/usb/cx231xx/cx231xx-cards.c +++ b/drivers/media/usb/cx231xx/cx231xx-cards.c @@ -1684,7 +1684,7 @@ 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;