diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h
index 75a453870498..f43d52a44d09 100644
--- a/tools/include/nolibc/string.h
+++ b/tools/include/nolibc/string.h
@@ -147,6 +147,15 @@ size_t nolibc_strlen(const char *str)
 #define strlen(str) nolibc_strlen((str))
 #endif
 
+static __attribute__((unused))
+size_t strnlen(const char *str, size_t maxlen)
+{
+	size_t len;
+
+	for (len = 0; (len < maxlen) && str[len]; len++);
+	return len;
+}
+
 static __attribute__((unused))
 size_t strlcat(char *dst, const char *src, size_t size)
 {