media: imon: Fix null-ptr-deref in imon_probe

commit 58fd55e838276a0c13d1dc7c387f90f25063cbf3 upstream.

It seems that the return value of usb_ifnum_to_if() can be NULL and
needs to be checked.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
index 3f175eb..3fb5949 100644 (file)
--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -2318,6 +2318,11 @@ static int __devinit imon_probe(struct usb_interface *interface,
        mutex_lock(&driver_lock);
 
        first_if = usb_ifnum_to_if(usbdev, 0);
+       if (!first_if) {
+               ret = -ENODEV;
+               goto fail;
+       }
+
        first_if_ctx = usb_get_intfdata(first_if);
 
        if (ifnum == 0) {