The state.json should be generated prior to the creation of the cgroup.

libcontainer/process_linux.go

@@ -561,6 +561,13 @@ func (p *initProcess) start() (retErr error) {
 		}
 	}()
 
+	// A SIGKILL can happen at any time, and without the state.json, 
+	// the 'runc delete --force' command won't be able to clear the cgroup.
+	_, err = p.container.updateState(p)
+	if err != nil {
+		return fmt.Errorf("unable to store init state: %w", err)
+	}
+
 	// Do this before syncing with child so that no children can escape the
 	// cgroup. We don't need to worry about not doing this and not being root
 	// because we'd be using the rootless cgroup manager in that case.