iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ip_gre: set tunnel hlen properly in erspan_tunnel_init

Browse Source 
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>
This commit is contained in:
Xin Long 2017-10-01 22:00:55 +08:00 committed by David S. Miller
parent 5513d08d29
commit c122fda271
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
net/ipv4/ip_gre.c
View File

@ -1245,7 +1245,9 @@ static int erspan_tunnel_init(struct net_device *dev)
tunnel->tun_hlen = 8;
tunnel->parms.iph.protocol = IPPROTO_GRE;
t_hlen = tunnel->hlen + sizeof(struct iphdr) + sizeof(struct erspanhdr);
tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
sizeof(struct erspanhdr);
t_hlen = tunnel->hlen + sizeof(struct iphdr);
dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
dev->mtu = ETH_DATA_LEN - t_hlen - 4;