commit 2d665034f239412927b1e71329f20f001c92da09
Author: Petr Machata <[email protected]>
Date: Thu May 17 16:36:51 2018 +0200
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: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <[email protected]>
Acked-by: William Tu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Cc: Greg Rose <[email protected]>
Signed-off-by: William Tu <[email protected]>
---
datapath/linux/compat/ip6_gre.c | 93 +++++++++++++++++++++++++++++++++++++----
1 file changed, 84 insertions(+), 9 deletions(-)
diff --git a/datapath/linux/compat/ip6_gre.c b/datapath/linux/compat/ip6_gre.c
index 7c06d732285c..3a82c3d0fc6b 100644
--- a/datapath/linux/compat/ip6_gre.c
+++ b/datapath/linux/compat/ip6_gre.c
@@ -79,6 +79,7 @@ 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);
#define gre_calc_hlen rpl_ip_gre_calc_hlen
static int rpl_ip_gre_calc_hlen(__be16 o_flags)
@@ -1979,6 +1980,19 @@ static const struct net_device_ops ip6gre_tap_netdev_ops
= {
#endif
};
+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;
@@ -2002,12 +2016,7 @@ 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;
@@ -2016,7 +2025,7 @@ static int ip6erspan_tap_init(struct net_device *dev)
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;
}
@@ -2387,6 +2396,72 @@ static void ip6erspan_tap_setup(struct net_device *dev)
netif_keep_dst(dev);
}
+#ifdef HAVE_IP6GRE_EXTACK
+static int rpl_ip6erspan_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+#else
+static int rpl_ip6erspan_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[])
+#endif
+{
+#ifdef HAVE_IP6GRE_EXTACK
+ int err = ip6gre_newlink_common(src_net, dev, tb, data, extack);
+#else
+ int err = ip6gre_newlink_common(src_net, dev, tb, data);
+#endif
+ 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;
+}
+#define ip6erspan_newlink rpl_ip6erspan_newlink
+
+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;
+}
+
+#ifdef HAVE_IP6GRE_EXTACK
+static int rpl_ip6erspan_changelink(struct net_device *dev, struct nlattr
*tb[],
+ struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+#else
+static int rpl_ip6erspan_changelink(struct net_device *dev, struct nlattr
*tb[],
+ struct nlattr *data[])
+#endif
+{
+ struct ip6gre_net *ign = net_generic(dev_net(dev), ip6gre_net_id);
+ struct __ip6_tnl_parm p;
+ struct ip6_tnl *t;
+#ifdef HAVE_IP6GRE_EXTACK
+ t = ip6gre_changelink_common(dev, tb, data, &p, extack);
+#else
+ t = ip6gre_changelink_common(dev, tb, data, &p);
+#endif
+ 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;
+}
+#define ip6erspan_changelink rpl_ip6erspan_changelink
+
static struct rtnl_link_ops ip6gre_link_ops __read_mostly = {
.kind = "ip6gre",
.maxtype = RPL_IFLA_GRE_MAX,
@@ -2428,8 +2503,8 @@ 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,
.dellink = ip6gre_dellink,
.get_size = ip6gre_get_size,
.fill_info = ip6gre_fill_info,
