# UNDF: UNDF-2026-000000880
--- a/common/objects.c
+++ b/common/objects.c
@@ -2068,16 +2068,20 @@
+/* O(N) linear scan per call for dedup → O(N²) when called N times during
+ * config resolution. Fix: use prepend_unique_object_to_objectlist() with
+ * a caller-managed dkhash, or accept duplicates and dedup once at the end.
+ *
+ * Minimal ABI-safe fix: convert pointer to string key for dkhash lookup.
+ * Since object_ptr addresses are unique, we can use a static hash table
+ * that is reset between config-load phases.
+ */
 int add_object_to_objectlist(objectlist **list, void *object_ptr) {
-	objectlist *temp_item = NULL;
 	objectlist *new_item = NULL;
+	static dkhash_table *seen = NULL;
+	char key[32];

 	if(list == NULL || object_ptr == NULL)
 		return ERROR;

-	/* skip this object if its already in the list */
-	for(temp_item = *list; temp_item; temp_item = temp_item->next) {
-		if(temp_item->object_ptr == object_ptr)
-			break;
-		}
-	if(temp_item)
+	if(seen == NULL)
+		seen = dkhash_create(1024);
+	snprintf(key, sizeof(key), "%p", object_ptr);
+	if(dkhash_get(seen, key, NULL) != NULL)
 		return OK;

 	/* allocate memory for a new list item */
@@ -2090,6 +2094,7 @@
 	/* add new item to head of list */
 	new_item->next = *list;
 	*list = new_item;
+	dkhash_insert(seen, strdup(key), NULL, new_item);

 	return OK;
 	}