From: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx> [ Upstream commit 4123f637a5129470ff9d3cb00a5a4e213f2e15cc ] ip6erspan driver calls ether_setup(), after commit 61e84623ace3 ("net: centralize net_device min/max MTU checking"), the range of mtu is [min_mtu, max_mtu], which is [68, 1500] by default. It causes the dev mtu of the erspan device to not be greater than 1500, this limit value is not correct for ip6erspan tap device. Fixes: 61e84623ace3 ("net: centralize net_device min/max MTU checking") Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx> Acked-by: William Tu <u9012063@xxxxxxxxx> Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ipv6/ip6_gre.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index b3515a4f1303..1f2d0022ba6f 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -2218,6 +2218,7 @@ static void ip6erspan_tap_setup(struct net_device *dev) { ether_setup(dev); + dev->max_mtu = 0; dev->netdev_ops = &ip6erspan_netdev_ops; dev->needs_free_netdev = true; dev->priv_destructor = ip6gre_dev_free; -- 2.20.1