From: Xin Long <lucien.xin@gmail.com>
Date: Tue, 27 Feb 2018 19:19:39 +0800
Subject: ip_gre: fix IFLA_MTU ignored on NEWLINK
Patch-mainline: v4.16-rc5
Git-commit: ffc2b6ee417435605ee8bb1eb4c8f02e9ff4b4a5
References: bsc#1076830
It's safe to remove the setting of dev's needed_headroom and mtu in
__gre_tunnel_init, as discussed in [1], ip_tunnel_newlink can do it
properly.
Now Eric noticed that it could cover the mtu value set in do_setlink
when creating a ip_gre dev. It makes IFLA_MTU param not take effect.
So this patch is to remove them to make IFLA_MTU work, as in other
ipv4 tunnels.
[1]: https://patchwork.ozlabs.org/patch/823504/
Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Reported-by: Eric Garver <e@erig.me>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
SLE15: omit erspan part (patches code not added yet)
---
net/ipv4/ip_gre.c | 3 ---
1 file changed, 3 deletions(-)
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -702,9 +702,6 @@ static void __gre_tunnel_init(struct net_device *dev)
t_hlen = tunnel->hlen + sizeof(struct iphdr);
- dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
- dev->mtu = ETH_DATA_LEN - t_hlen - 4;
-
dev->features |= GRE_FEATURES;
dev->hw_features |= GRE_FEATURES;