diff --git a/common/resources.tf b/common/resources.tf
index 26f5c4d..560ad3a 100644
--- a/common/resources.tf
+++ b/common/resources.tf
@@ -39,7 +39,7 @@ resource "aws_security_group" "this_security_group" {
 
   # ingress self (list with one or zero items)
   dynamic "ingress" {
-    for_each = var.enable_self ? local.self_port_map : {}
+    for_each = var.enable_self ? local.self_port_map : []
     iterator = sg
     content {
       description = "${local.short_description}: self ${sg.value["description"]}"