redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

net: ip6_gre: Fix ip6erspan hlen calculation 

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: 5a963eb61b ("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>
hifive-unleashed-5.1
Petr Machata 2018-05-17 16:36:51 +02:00 committed by David S. Miller
parent c8632fc30b
commit 2d665034f2
1 changed files with 65 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

74
net/ipv6/ip6_gre.c
View File

@ -81,6 +81,7 @@ static int ip6gre_tunnel_init(struct net_device *dev);
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 */
@ -1754,6 +1755,19 @@ static const struct net_device_ops ip6gre_tap_netdev_ops = {
.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;
@ -1777,12 +1791,7 @@ static int ip6erspan_tap_init(struct net_device *dev)
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;
@ -1790,7 +1799,7 @@ static int ip6erspan_tap_init(struct net_device *dev)
dev->mtu -= 8;
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
ip6gre_tnl_link_config(tunnel, 1);
ip6erspan_tnl_link_config(tunnel, 1);
return 0;
}
@ -2121,6 +2130,53 @@ static void ip6erspan_tap_setup(struct net_device *dev)
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,
@ -2157,8 +2213,8 @@ static struct rtnl_link_ops ip6erspan_tap_ops __read_mostly = {
.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,