diff --git a/package/network/services/ppp/patches/500-add-pptp-plugin.patch b/package/network/services/ppp/patches/500-add-pptp-plugin.patch
index d984e1b1628..54a160d33f8 100644
--- a/package/network/services/ppp/patches/500-add-pptp-plugin.patch
+++ b/package/network/services/ppp/patches/500-add-pptp-plugin.patch
@@ -1083,6 +1083,7 @@
 +#include <string.h>
 +#include <ctype.h>
 +#include <fcntl.h>
++#include "pppd.h"
 +#include "pptp_msg.h"
 +#include "pptp_ctrl.h"
 +#include "pptp_options.h"