diff --git a/src/pty/ntapi_pty_query.c b/src/pty/ntapi_pty_query.c
index 6754c77..7550ad3 100644
--- a/src/pty/ntapi_pty_query.c
+++ b/src/pty/ntapi_pty_query.c
@@ -63,6 +63,8 @@ int32_t	__stdcall __ntapi_pty_query(
 		msg.data.ctlinfo.ctxarg[3] = inherit->any[3];
 
 		hport = pty ? pty : __ntapi_internals()->hport_tty_session;
+	} else {
+		return NT_STATUS_INVALID_INFO_CLASS;
 	}
 
 	if ((status = __ntapi->zw_request_wait_reply_port(hport,&msg,&msg)))