From e1043a4bb9fce6cfc7d55c5767e429a18ac8c4eb Mon Sep 17 00:00:00 2001 From: Mohammed Gamal Date: Mon, 16 Oct 2017 15:20:32 +0200 Subject: [PATCH] xen-netfront, xen-netback: Use correct minimum MTU values RFC791 specifies the minimum MTU to be 68, while xen-net{front|back} drivers use a minimum value of 0. When set MTU to 0~67 with xen_net{front|back} driver, the network will become unreachable immediately, the guest can no longer be pinged. xen_net{front|back} should not allow the user to set this value which causes network problems. Reported-by: Chen Shi Signed-off-by: Mohammed Gamal Acked-by: Wei Liu Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky --- drivers/net/xen-netback/interface.c | 2 +- drivers/net/xen-netfront.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index ee8ed9da00ad..4491ca5aee90 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -486,7 +486,7 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, dev->tx_queue_len = XENVIF_QUEUE_LENGTH; - dev->min_mtu = 0; + dev->min_mtu = ETH_MIN_MTU; dev->max_mtu = ETH_MAX_MTU - VLAN_ETH_HLEN; /* diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 523387e71a80..8b8689c6d887 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1316,7 +1316,7 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) netdev->features |= netdev->hw_features; netdev->ethtool_ops = &xennet_ethtool_ops; - netdev->min_mtu = 0; + netdev->min_mtu = ETH_MIN_MTU; netdev->max_mtu = XEN_NETIF_MAX_TX_SIZE; SET_NETDEV_DEV(netdev, &dev->dev); -- 2.20.1