diff --git a/libc/kernel/uapi/linux/ip.h b/libc/kernel/uapi/linux/ip.h
index 766a808..9249f5c 100644
--- a/libc/kernel/uapi/linux/ip.h
+++ b/libc/kernel/uapi/linux/ip.h
@@ -19,6 +19,7 @@
 #ifndef _UAPI_LINUX_IP_H
 #define _UAPI_LINUX_IP_H
 #include <linux/types.h>
+#include <linux/stddef.h>
 #include <asm/byteorder.h>
 #define IPTOS_TOS_MASK 0x1E
 #define IPTOS_TOS(tos) ((tos) & IPTOS_TOS_MASK)