[ovs-dev] [PATCH] ovn-controller: Fix flow generation for container traffic.

[Gurucharan Shetty]

In table 64, when a vlan tag is set on a packet
destined to a container running inside a VM, we currently
don't revert it. This has an unintended consequence for
broadcast traffic when one endpoint of the braodcast
traffic is a plain VM (without containers running inside) where
the previously set tag would remain in the packets sent to the VM.

This commit fixes the above problem by popping the VLAN
and resetting the input port after outputting the packet
with a vlan tag to a container logical port.

Signed-off-by: Gurucharan Shetty <gshetty at nicira.com>
---
 ovn/controller/physical.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/ovn/controller/physical.c b/ovn/controller/physical.c
index 9e7f2f4..8a63ee9 100644
--- a/ovn/controller/physical.c
+++ b/ovn/controller/physical.c
@@ -241,6 +241,19 @@ physical_run(struct controller_ctx *ctx)
             sf->mask.be16 = OVS_BE16_MAX;
         }
         ofpact_put_OUTPUT(&ofpacts)->port = ofport;
+        if (tag) {
+            /* Revert the tag added to the packets headed to containers
+             * in the previous step. If we don't do this, the packets
+             * that are to be broadcasted to a VM in the same logical
+             * switch will also contain the tag. Also revert the zero'd
+             * in_port. */
+            ofpact_put_STRIP_VLAN(&ofpacts);
+
+            struct ofpact_set_field *sf = ofpact_put_SET_FIELD(&ofpacts);
+            sf->field = mf_from_id(MFF_IN_PORT);
+            sf->value.be16 = htons(ofport);
+            sf->mask.be16 = OVS_BE16_MAX;
+        }
         ofctrl_add_flow(64, 50, &match, &ofpacts);
     }
 
-- 
1.7.9.5