[PATCH] sit: Fix ipip6_tunnel_lookup device matching criteria

As of 4fddbf5d78, when looking up a tunnel, tunnel's underlying
interface (t->parms.link) is verified to match incoming traffic's
ingress device.

However the comparison was incorrectly based on skb->dev->iflink.

Instead, dev->ifindex should be used, which correctly represents the
interface from which the IP stack hands the ipip6 packets.

This allows setting up sit tunnels bound to vlan interfaces (otherwise
incoming ipip6 traffic on the vlan interface was dropped due to
ipip6_tunnel_lookup match failure).

Signed-off-by: Shmulik Ladkani <redacted>
---
 net/ipv6/sit.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 2e9ba035fb..6163f851dc 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c

@@ -101,19 +101,19 @@ static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
 		if (local == t->parms.iph.saddr &&
 		    remote == t->parms.iph.daddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
 		if (remote == t->parms.iph.daddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
 		if (local == t->parms.iph.saddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}

-- 
1.9.0

Le 14/08/2014 11:32, Shmulik Ladkani a écrit :

As of 4fddbf5d78, when looking up a tunnel, tunnel's underlying

Please, put also the subject of the commit like this:
4fddbf5d7854 ("sit: strictly restrict incoming traffic to tunnel link device")

interface (t->parms.link) is verified to match incoming traffic's
ingress device.

However the comparison was incorrectly based on skb->dev->iflink.

Instead, dev->ifindex should be used, which correctly represents the
interface from which the IP stack hands the ipip6 packets.

This allows setting up sit tunnels bound to vlan interfaces (otherwise
incoming ipip6 traffic on the vlan interface was dropped due to
ipip6_tunnel_lookup match failure).

Signed-off-by: Shmulik Ladkani <redacted>

Acked-by: Nicolas Dichtel <redacted>

As of 4fddbf5d78 ("sit: strictly restrict incoming traffic to tunnel
link device"), when looking up a tunnel, tunnel's underlying
interface (t->parms.link) is verified to match incoming traffic's
ingress device.

However the comparison was incorrectly based on skb->dev->iflink.

Instead, dev->ifindex should be used, which correctly represents the
interface from which the IP stack hands the ipip6 packets.

This allows setting up sit tunnels bound to vlan interfaces (otherwise
incoming ipip6 traffic on the vlan interface was dropped due to
ipip6_tunnel_lookup match failure).

Signed-off-by: Shmulik Ladkani <redacted>
---
 net/ipv6/sit.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 2e9ba035fb..6163f851dc 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c

@@ -101,19 +101,19 @@ static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
 		if (local == t->parms.iph.saddr &&
 		    remote == t->parms.iph.daddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
 		if (remote == t->parms.iph.daddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}
 	for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
 		if (local == t->parms.iph.saddr &&
-		    (!dev || !t->parms.link || dev->iflink == t->parms.link) &&
+		    (!dev || !t->parms.link || dev->ifindex == t->parms.link) &&
 		    (t->dev->flags & IFF_UP))
 			return t;
 	}

-- 
1.9.0

Le 14/08/2014 12:49, Shmulik Ladkani a écrit :

As of 4fddbf5d78 ("sit: strictly restrict incoming traffic to tunnel
link device"), when looking up a tunnel, tunnel's underlying

Nitpicking, but David always asks to not split subject in two lines, even
if it's more than 80 columns.

Hello.

On 8/14/2014 1:32 PM, Shmulik Ladkani wrote:

As of 4fddbf5d78, when looking up a tunnel, tunnel's underlying

    Please also specify that commit's summary line in parens.

interface (t->parms.link) is verified to match incoming traffic's
ingress device.

However the comparison was incorrectly based on skb->dev->iflink.

Instead, dev->ifindex should be used, which correctly represents the
interface from which the IP stack hands the ipip6 packets.

This allows setting up sit tunnels bound to vlan interfaces (otherwise
incoming ipip6 traffic on the vlan interface was dropped due to
ipip6_tunnel_lookup match failure).

Signed-off-by: Shmulik Ladkani <redacted>

WBR, Sergei