diff --git a/headers/private/kernel/sysctl.h b/headers/private/kernel/sysctl.h
index 7615c2c5da..1d871b6b4b 100644
--- a/headers/private/kernel/sysctl.h
+++ b/headers/private/kernel/sysctl.h
@@ -5,6 +5,8 @@
 #ifndef _SYS_SYSCTL_H
 #define _SYS_SYSCTL_H
 
+#include <sys/types.h>
+
 /* This file contains definitions for the sysctl call.
  * The call uses a heirachy of names for objects that can be
  * examined or modified. The name is expressed as a sequence