Staging: batman-adv: Update mtu of bat device by changing mtu of slave device

We must reduce our own mtu when we reduce the mtu of any device we use
to transfer our packets. Otherwise we may accept to large packets which
gets dropped by the actual device.

Reported-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/batman-adv/hard-interface.c b/drivers/staging/batman-adv/hard-interface.c
index a58a89a7aa0e620536cb0c71acc896880c2c80b9..a587da9c827e095dac83a3937b6bd4b91f767250 100644 (file)
--- a/drivers/staging/batman-adv/hard-interface.c
+++ b/drivers/staging/batman-adv/hard-interface.c
@@ -469,6 +469,10 @@ static int hard_if_event(struct notifier_block *this,
        case NETDEV_UNREGISTER:
                hardif_remove_interface(batman_if);
                break;
+       case NETDEV_CHANGEMTU:
+               if (batman_if->soft_iface)
+                       update_min_mtu(batman_if->soft_iface);
+               break;
        case NETDEV_CHANGEADDR:
                if (batman_if->if_status == IF_NOT_IN_USE)
                        goto out;