4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long <lucien.xin@xxxxxxxxx> [ Upstream commit 84581bdae9587023cea1d139523f0ef0f28bd88d ] After erspan_ver is introudced, if erspan_ver is not set in iproute, its value will be left 0 by default. Since Commit 02f99df1875c ("erspan: fix invalid erspan version."), it has broken the traffic due to the version check in erspan_xmit if users are not aware of 'erspan_ver' param, like using an old version of iproute. To fix this compatibility problem, it sets erspan_ver to 1 by default when adding an erspan dev in erspan_setup. Note that we can't do it in ipgre_netlink_parms, as this function is also used by ipgre_changelink. Fixes: 02f99df1875c ("erspan: fix invalid erspan version.") Reported-by: Jianlin Shi <jishi@xxxxxxxxxx> Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/ip_gre.c | 3 +++ net/ipv6/ip6_gre.c | 1 + 2 files changed, 4 insertions(+) --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -1511,11 +1511,14 @@ nla_put_failure: static void erspan_setup(struct net_device *dev) { + struct ip_tunnel *t = netdev_priv(dev); + ether_setup(dev); dev->netdev_ops = &erspan_netdev_ops; dev->priv_flags &= ~IFF_TX_SKB_SHARING; dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; ip_tunnel_setup(dev, erspan_net_id); + t->erspan_ver = 1; } static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -1776,6 +1776,7 @@ static void ip6gre_netlink_parms(struct if (data[IFLA_GRE_COLLECT_METADATA]) parms->collect_md = true; + parms->erspan_ver = 1; if (data[IFLA_GRE_ERSPAN_VER]) parms->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);