Fixes #6177: Prevent VM interface from being assigned as its own parent

docs/release-notes/version-2.11.md

@@ -125,6 +125,7 @@ A new provider network model has been introduced to represent the boundary of a
 * [#6171](https://github.com/netbox-community/netbox/issues/6171) - Fix display of horizontally-scrolling object lists
 * [#6173](https://github.com/netbox-community/netbox/issues/6173) - Fix assigned device/VM count when bulk editing/deleting device roles
 * [#6176](https://github.com/netbox-community/netbox/issues/6176) - Correct position of MAC address field when creating VM interfaces
+* [#6177](https://github.com/netbox-community/netbox/issues/6177) - Prevent VM interface from being assigned as its own parent
 
 ### Other Changes
 

netbox/virtualization/models.py

@@ -463,6 +463,10 @@ class VMInterface(PrimaryModel, BaseInterface):
                           f"({self.parent.virtual_machine})."
             })
 
+        # An interface cannot be its own parent
+        if self.pk and self.parent_id == self.pk:
+            raise ValidationError({'parent': "An interface cannot be its own parent."})
+
         # Validate untagged VLAN
         if self.untagged_vlan and self.untagged_vlan.site not in [self.virtual_machine.site, None]:
             raise ValidationError({