--- a/compat/backport-3.15.c
+++ b/compat/backport-3.15.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/of.h>
+#include <linux/string.h>
#include <net/net_namespace.h>
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,5,0))