watchdog: pcwd_usb: fix NULL-deref at probe
authorJohan Hovold <johan@kernel.org>
Mon, 13 Mar 2017 12:49:45 +0000 (13:49 +0100)
committerWim Van Sebroeck <wim@iguana.be>
Thu, 18 May 2017 16:51:34 +0000 (18:51 +0200)
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/pcwd_usb.c

index 99ebf6e..5615f40 100644 (file)
@@ -630,6 +630,9 @@ static int usb_pcwd_probe(struct usb_interface *interface,
                return -ENODEV;
        }
 
+       if (iface_desc->desc.bNumEndpoints < 1)
+               return -ENODEV;
+
        /* check out the endpoint: it has to be Interrupt & IN */
        endpoint = &iface_desc->endpoint[0].desc;