engine: resources: mount: Fix the dbus call for reloading systemd

The Reload method cannot just be invoked on the administrative DBus object. Just like the method for reloading specific units, it needs to be invoked on the proper DBus service, addressing the proper object and using the right interface. Added an additional constant for the systemd DBus service. Even though it shares the same value as the interface base name, this is happenstance and it's technically incorrect to open a connection to an interface name. The connection needs a service name. Fixes purpleidea#509
xlai89 · Jun 4, 2019 · 191a249 · 191a249
1 parent a235b76
commit 191a249
Showing 1 changed file with 10 additions and 2 deletions.
diff --git a/engine/resources/mount.go b/engine/resources/mount.go
@@ -75,6 +75,8 @@ const (
  // diskByLabel is the location of symlinks for partitions by label.
  diskByPartLabel = devDisk + "by-partlabel/"
 
+ // dbusSystemdService is the service to connect to systemd itself.
+ dbusSystemd1Service = "org.freedesktop.systemd1"
  // dbusSystemd1Interface is the base systemd1 path.
  dbusSystemd1Path = "/org/freedesktop/systemd1"
  // dbusUnitPath is the dbus path where mount unit files are found.
@@ -88,6 +90,9 @@ const (
  dbusManagerInterface = dbusSystemd1Interface + ".Manager"
  // dbusRestartUnit is the dbus method for restarting systemd units.
  dbusRestartUnit = dbusManagerInterface + ".RestartUnit"
+ // dbusReloadSystemd is the dbus method for reloading systemd settings.
+ // (i.e. systemctl daemon-reload)
+ dbusReloadSystemd = dbusManagerInterface + ".Reload"
  // restartTimeout is the delay before restartUnit is assumed to have
  // failed.
  dbusRestartCtxTimeout = 10
@@ -576,7 +581,10 @@ func mountReload() error {
  }
  defer conn.Close()
  // systemctl daemon-reload
- conn.BusObject().Call("Reload", 0)
+ call := conn.Object(dbusSystemd1Service, dbusSystemd1Path).Call(dbusReloadSystemd, 0)
+ if call.Err != nil {
+ return errwrap.Wrapf(call.Err, "error reloading systemd")
+ }
 
  // systemctl restart local-fs.target
  if err := restartUnit(conn, "local-fs.target"); err != nil {
@@ -619,7 +627,7 @@ func restartUnit(conn *dbus.Conn, unit string) error {
  defer conn.RemoveSignal(ch)
 
  // restart the unit
- sd1 := conn.Object(dbusSystemd1Interface, dbus.ObjectPath(dbusSystemd1Path))
+ sd1 := conn.Object(dbusSystemd1Service, dbus.ObjectPath(dbusSystemd1Path))
  if call := sd1.Call(dbusRestartUnit, 0, unit, "fail"); call.Err != nil {
  return errwrap.Wrapf(call.Err, "error restarting unit: %s", unit)
  }