datapath: Reset upper layer protocol info on internal devices.

It's possible that packets that are sent on internal devices (from
the OVS perspective) have already traversed the local IP stack.
After they go through the internal device, they will again travel
through the IP stack which may get confused by the presence of
existing information in the skb. The problem can be observed
when switching between namespaces. This clears out that information
to avoid problems but deliberately leaves other metadata alone.
This is to provide maximum flexibility in chaining together OVS
and other Linux components.

Bug #10995

Signed-off-by: Jesse Gross <jesse@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>

diff --git a/datapath/vport-internal_dev.c b/datapath/vport-internal_dev.c
index af7fe64976dd039e47c41f7279754865ccd551fd..4dc2eb479d7024586f9d85538ace6a48e119d6f0 100644 (file)
--- a/datapath/vport-internal_dev.c
+++ b/datapath/vport-internal_dev.c
@@ -25,6 +25,9 @@
 #include <linux/skbuff.h>
 #include <linux/version.h>
 
+#include <net/dst.h>
+#include <net/xfrm.h>
+
 #include "checksum.h"
 #include "datapath.h"
 #include "vlan.h"
@@ -289,6 +292,11 @@ static int internal_dev_recv(struct vport *vport, struct sk_buff *skb)
 #endif
 
        len = skb->len;
+
+       skb_dst_drop(skb);
+       nf_reset(skb);
+       secpath_reset(skb);
+
        skb->dev = netdev;
        skb->pkt_type = PACKET_HOST;
        skb->protocol = eth_type_trans(skb, netdev);