diff --git a/net/devif/devif_loopback.c b/net/devif/devif_loopback.c
index 485516dd18..02e9b73291 100644
--- a/net/devif/devif_loopback.c
+++ b/net/devif/devif_loopback.c
@@ -39,6 +39,7 @@
 
 #include <nuttx/config.h>
 
+#include <string.h>
 #include <debug.h>
 
 #include <nuttx/net/ip.h>