Input: cm109 - validate number of endpoints before using them
authorJohan Hovold <johan@kernel.org>
Thu, 16 Mar 2017 18:35:12 +0000 (11:35 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 30 Mar 2017 07:35:15 +0000 (09:35 +0200)
commit ac2ee9ba953afe88f7a673e1c0c839227b1d7891 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: c04148f915e5 ("Input: add driver for USB VoIP phones with CM109...")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/input/misc/cm109.c

index 9365535ba7f157b98138f6f0defb14d9e1ae782a..50a7faa504f722a9157a65b6ef76ccc900b77e0d 100644 (file)
@@ -675,6 +675,10 @@ static int cm109_usb_probe(struct usb_interface *intf,
        int error = -ENOMEM;
 
        interface = intf->cur_altsetting;
+
+       if (interface->desc.bNumEndpoints < 1)
+               return -ENODEV;
+
        endpoint = &interface->endpoint[0].desc;
 
        if (!usb_endpoint_is_int_in(endpoint))