copy_to_user() returns number of not copied bytes, not error code.
Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
                        retval = io_res;
                else {
                        io_res = copy_to_user(user_buffer, buffer, dev->report_size);
-                       if (io_res < 0)
+                       if (io_res)
                                retval = -EFAULT;
                }
                break;
                        }
                        io_res = copy_to_user((struct iowarrior_info __user *)arg, &info,
                                         sizeof(struct iowarrior_info));
-                       if (io_res < 0)
+                       if (io_res)
                                retval = -EFAULT;
                        break;
                }