diff --git a/vendor/github.com/opencontainers/runc/libcontainer/cgroups/systemd/apply_systemd.go b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/systemd/apply_systemd.go
index b010b4b3..0cf76cce 100644
--- a/vendor/github.com/opencontainers/runc/libcontainer/cgroups/systemd/apply_systemd.go
+++ b/vendor/github.com/opencontainers/runc/libcontainer/cgroups/systemd/apply_systemd.go
@@ -288,6 +288,9 @@ func (m *Manager) Apply(pid int) error {
 		}
 	}
 
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
 	if _, err := theConn.StartTransientUnit(unitName, "replace", properties, nil); err != nil && !isUnitExists(err) {
 		return err
 	}