nm-sudo: expect unknown interface in _bus_method_call()

GDBus will invoke the method_call callback also for the Get/Set
functions. Thus, we need to check the interface_name and handle
them (actually, there is nothing to handle, no properties exist).

Also, "Ping" method only exists for testing. It is usually not called
in production, so check for "GetFD" first.

1 files changed, 17 insertions, 5 deletions

diff --git a/src/nm-sudo/nm-sudo.c b/src/nm-sudo/nm-sudo.c
index c199d8994b..d8cf42f3c8 100644
--- a/src/nm-sudo/nm-sudo.c
+++ b/src/nm-sudo/nm-sudo.c
@@ -290,14 +290,26 @@ _bus_method_call(GDBusConnection *      connection,
           method_name,
           g_variant_get_type_string(parameters));
 
+    if (!nm_streq(interface_name, NM_SUDO_DBUS_IFACE_NAME))
+        goto out_unknown_method;
+
+    if (nm_streq(method_name, "GetFD")) {
+        g_variant_get(parameters, "(u)", &arg_u);
+        _handle_get_fd(gl, invocation, arg_u);
+        return;
+    }
     if (nm_streq(method_name, "Ping")) {
         g_variant_get(parameters, "(&s)", &arg_s);
         _handle_ping(gl, invocation, arg_s);
-    } else if (nm_streq(method_name, "GetFD")) {
-        g_variant_get(parameters, "(u)", &arg_u);
-        _handle_get_fd(gl, invocation, arg_u);
-    } else
-        nm_assert_not_reached();
+        return;
+    }
+
+out_unknown_method:
+    g_dbus_method_invocation_return_error(invocation,
+                                          G_DBUS_ERROR,
+                                          G_DBUS_ERROR_UNKNOWN_METHOD,
+                                          "Unknown method %s",
+                                          method_name);
 }
 
 static GDBusInterfaceInfo *const interface_info = NM_DEFINE_GDBUS_INTERFACE_INFO(