Fix NULL-pointer dereference in open() should a malicious device lack
the expected endpoints:
Unable to handle kernel NULL pointer dereference at virtual address 
00000030
..
[<
bf06a6b0>] (ti_open [ti_usb_3410_5052]) from [<
bf02e118>] (serial_port_activate+0x68/0x98 [usbserial])
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
                goto free_tdev;
        }
 
+       if (serial->num_bulk_in < serial->num_ports ||
+                       serial->num_bulk_out < serial->num_ports) {
+               dev_err(&serial->interface->dev, "missing endpoints\n");
+               status = -ENODEV;
+               goto free_tdev;
+       }
+
        return 0;
 
 free_tdev: