4.16-stable review patch. If anyone has any objections, please let me know.
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From: Petr Machata petrm@mellanox.com
[ Upstream commit 2d665034f239412927b1e71329f20f001c92da09 ]
Even though ip6erspan_tap_init() sets up hlen and tun_hlen according to what ERSPAN needs, it goes ahead to call ip6gre_tnl_link_config() which overwrites these settings with GRE-specific ones.
Similarly for changelink callbacks, which are handled by ip6gre_changelink() calls ip6gre_tnl_change() calls ip6gre_tnl_link_config() as well.
The difference ends up being 12 vs. 20 bytes, and this is generally not a problem, because a 12-byte request likely ends up allocating more and the extra 8 bytes are thus available. However correct it is not.
So replace the newlink and changelink callbacks with an ERSPAN-specific ones, reusing the newly-introduced _common() functions.
Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support") Signed-off-by: Petr Machata petrm@mellanox.com Acked-by: William Tu u9012063@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/ip6_gre.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 65 insertions(+), 9 deletions(-)
--- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -81,6 +81,7 @@ static int ip6gre_tunnel_init(struct net static void ip6gre_tunnel_setup(struct net_device *dev); static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t); static void ip6gre_tnl_link_config(struct ip6_tnl *t, int set_mtu); +static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu);
/* Tunnel hash table */
@@ -1746,6 +1747,19 @@ static const struct net_device_ops ip6gr .ndo_get_iflink = ip6_tnl_get_iflink, };
+static int ip6erspan_calc_hlen(struct ip6_tnl *tunnel) +{ + int t_hlen; + + tunnel->tun_hlen = 8; + tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + + erspan_hdr_len(tunnel->parms.erspan_ver); + + t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); + tunnel->dev->hard_header_len = LL_MAX_HEADER + t_hlen; + return t_hlen; +} + static int ip6erspan_tap_init(struct net_device *dev) { struct ip6_tnl *tunnel; @@ -1769,12 +1783,7 @@ static int ip6erspan_tap_init(struct net return ret; }
- tunnel->tun_hlen = 8; - tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + - erspan_hdr_len(tunnel->parms.erspan_ver); - t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); - - dev->hard_header_len = LL_MAX_HEADER + t_hlen; + t_hlen = ip6erspan_calc_hlen(tunnel); dev->mtu = ETH_DATA_LEN - t_hlen; if (dev->type == ARPHRD_ETHER) dev->mtu -= ETH_HLEN; @@ -1783,7 +1792,7 @@ static int ip6erspan_tap_init(struct net
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; tunnel = netdev_priv(dev); - ip6gre_tnl_link_config(tunnel, 1); + ip6erspan_tnl_link_config(tunnel, 1);
return 0; } @@ -2108,6 +2117,53 @@ static void ip6erspan_tap_setup(struct n netif_keep_dst(dev); }
+static int ip6erspan_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + int err = ip6gre_newlink_common(src_net, dev, tb, data, extack); + struct ip6_tnl *nt = netdev_priv(dev); + struct net *net = dev_net(dev); + + if (!err) { + ip6erspan_tnl_link_config(nt, !tb[IFLA_MTU]); + ip6gre_tunnel_link(net_generic(net, ip6gre_net_id), nt); + } + return err; +} + +static void ip6erspan_tnl_link_config(struct ip6_tnl *t, int set_mtu) +{ + ip6gre_tnl_link_config_common(t); + ip6gre_tnl_link_config_route(t, set_mtu, ip6erspan_calc_hlen(t)); +} + +static int ip6erspan_tnl_change(struct ip6_tnl *t, + const struct __ip6_tnl_parm *p, int set_mtu) +{ + ip6gre_tnl_copy_tnl_parm(t, p); + ip6erspan_tnl_link_config(t, set_mtu); + return 0; +} + +static int ip6erspan_changelink(struct net_device *dev, struct nlattr *tb[], + struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id); + struct __ip6_tnl_parm p; + struct ip6_tnl *t; + + t = ip6gre_changelink_common(dev, tb, data, &p, extack); + if (IS_ERR(t)) + return PTR_ERR(t); + + ip6gre_tunnel_unlink(ign, t); + ip6erspan_tnl_change(t, &p, !tb[IFLA_MTU]); + ip6gre_tunnel_link(ign, t); + return 0; +} + static struct rtnl_link_ops ip6gre_link_ops __read_mostly = { .kind = "ip6gre", .maxtype = IFLA_GRE_MAX, @@ -2144,8 +2200,8 @@ static struct rtnl_link_ops ip6erspan_ta .priv_size = sizeof(struct ip6_tnl), .setup = ip6erspan_tap_setup, .validate = ip6erspan_tap_validate, - .newlink = ip6gre_newlink, - .changelink = ip6gre_changelink, + .newlink = ip6erspan_newlink, + .changelink = ip6erspan_changelink, .get_size = ip6gre_get_size, .fill_info = ip6gre_fill_info, .get_link_net = ip6_tnl_get_link_net,