diff --git a/openbsd-compat/freezero.c b/openbsd-compat/freezero.c
index ca5de785b..90b9d3813 100644
--- a/openbsd-compat/freezero.c
+++ b/openbsd-compat/freezero.c
@@ -23,6 +23,8 @@
 void
 freezero(void *ptr, size_t sz)
 {
+	if (ptr == NULL)
+		return;
 	explicit_bzero(ptr, sz);
 	free(ptr);
 }