ip_gre: set tunnel hlen properly in erspan_tunnel_init
According to __gre_tunnel_init, tunnel->hlen should be set as the
headers' length between inner packet and outer iphdr.
It would be used especially to calculate a proper mtu when updating
mtu in tnl_update_pmtu. Now without setting it, a bigger mtu value
than expected would be updated, which hurts performance a lot.
This patch is to fix it by setting tunnel->hlen with:
tunnel->tun_hlen + tunnel->encap_hlen + sizeof(struct erspanhdr)
Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed