diff --git a/libc/include/net/if_ether.h b/libc/include/net/if_ether.h
index 121f9ac..8daa16b 100644
--- a/libc/include/net/if_ether.h
+++ b/libc/include/net/if_ether.h
@@ -34,6 +34,8 @@
 #ifndef _NET_IF_ETHER_H_
 #define _NET_IF_ETHER_H_
 
+#include <sys/types.h>
+
 #ifdef _KERNEL
 #ifdef _KERNEL_OPT
 #include "opt_mbuftrace.h"