diff --git a/src/core/devices/nm-device.c b/src/core/devices/nm-device.c
index d4d21a408a..ec8ea32831 100644
--- a/src/core/devices/nm-device.c
+++ b/src/core/devices/nm-device.c
@@ -6608,6 +6608,8 @@ device_ifindex_changed_cb(NMManager *manager, NMDevice *device_changed, NMDevice
 {
     NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE(self);
 
+    g_return_if_fail(priv->master_ifindex > 0);
+
     if (priv->master_ifindex != nm_device_get_ifindex(device_changed))
         return;