diff --git a/fff.h b/fff.h
index 28d6b79..7ab1a2a 100644
--- a/fff.h
+++ b/fff.h
@@ -27,7 +27,12 @@ SOFTWARE.
 #define FAKE_FUNCTIONS
 
 #include <stdarg.h>
+
+#ifndef __KERNEL__
 #include <string.h> /* For memset and memcpy */
+#else
+#include <linux/string.h> /* For memset and memcpy */
+#endif
 
 #define FFF_MAX_ARGS (20u)
 #ifndef FFF_ARG_HISTORY_LEN