ip6_tunnel: fix IFLA_MTU ignored on NEWLINK

[ Upstream commit a6aa80446234ec0ad38eecdb8efc59e91daae565 ]

Commit 128bb975dc3c ("ip6_gre: init dev->mtu and dev->hard_header_len
correctly") fixed IFLA_MTU ignored on NEWLINK for ip6_gre. The same
mtu fix is also needed for ip6_tunnel.

Note that dev->hard_header_len setting for ip6_tunnel works fine,
no need to fix it.

Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 417af5ea2509c46edbecb7b91b34a432250fdbdd..c7b202c1720dbeb205ae5f05cfb2bc6398043e8e 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1972,14 +1972,14 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
 {
        struct net *net = dev_net(dev);
        struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
-       struct ip6_tnl *nt, *t;
        struct ip_tunnel_encap ipencap;
+       struct ip6_tnl *nt, *t;
+       int err;
 
        nt = netdev_priv(dev);
 
        if (ip6_tnl_netlink_encap_parms(data, &ipencap)) {
-               int err = ip6_tnl_encap_setup(nt, &ipencap);
-
+               err = ip6_tnl_encap_setup(nt, &ipencap);
                if (err < 0)
                        return err;
        }
@@ -1995,7 +1995,11 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
                        return -EEXIST;
        }
 
-       return ip6_tnl_create2(dev);
+       err = ip6_tnl_create2(dev);
+       if (!err && tb[IFLA_MTU])
+               ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
+
+       return err;
 }
 
 static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],