core/dbus-manager: add missing assertion

diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c
index fa85a5e6980be5e1f4b5497bd56d7a94998af8ca..59a7f2bd356843e55f218453eac071af8c299cc6 100644 (file)
--- a/src/core/dbus-manager.c
+++ b/src/core/dbus-manager.c
@@ -772,6 +772,7 @@ static int method_generic_unit_operation(
 
         assert(message);
         assert(m);
+        assert(handler);
 
         /* Read the first argument from the command and pass the operation to the specified per-unit
          * method. */