diff --git a/src/shared/env-util.c b/src/shared/env-util.c
index 6a52fb960..598222c5b 100644
--- a/src/shared/env-util.c
+++ b/src/shared/env-util.c
@@ -406,7 +406,9 @@ char **strv_env_clean_log(char **e, const char *message) {
                 e[k++] = *p;
         }
 
-        e[k] = NULL;
+        if (e)
+                e[k] = NULL;
+
         return e;
 }