diff --git a/init/util.c b/init/util.c
index 0f69e1c5f..e1a3ee33a 100644
--- a/init/util.c
+++ b/init/util.c
@@ -329,9 +329,9 @@ void sanitize(char *s)
     if (!s)
         return;
 
-    for (; *s; s++) {
+    while (*s) {
         s += strspn(s, accept);
-        if (*s) *s = '_';
+        if (*s) *s++ = '_';
     }
 }