[ovs-dev] [PATCH ovn 1/2] ovn-northd: Fix Pre-LB logical flows with IPv4 and IPv6.

[Dumitru Ceara]

When both IPv4 and IPv6 load balancers were configured, the logical flows
that send packets that need to be load balanced to conntrack (for
defragmentation) were incorrectly trying to match on IPv6 fields.

Fix this issue by using two address sets, one for IPv4 and the other for
IPv6.

Signed-off-by: Dumitru Ceara <dceara at redhat.com>
---
 northd/ovn-northd.c |   29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c
index b6dc809..4ac9668 100644
--- a/northd/ovn-northd.c
+++ b/northd/ovn-northd.c
@@ -4654,13 +4654,14 @@ build_pre_lb(struct ovn_datapath *od, struct hmap *lflows,
     ovn_lflow_add(lflows, od, S_SWITCH_IN_PRE_LB, 0, "1", "next;");
     ovn_lflow_add(lflows, od, S_SWITCH_OUT_PRE_LB, 0, "1", "next;");
 
-    struct sset all_ips = SSET_INITIALIZER(&all_ips);
+    struct sset all_ips_v4 = SSET_INITIALIZER(&all_ips_v4);
+    struct sset all_ips_v6 = SSET_INITIALIZER(&all_ips_v6);
     bool vip_configured = false;
-    int addr_family = AF_INET;
     for (int i = 0; i < od->nbs->n_load_balancer; i++) {
         struct nbrec_load_balancer *lb = od->nbs->load_balancer[i];
         struct smap *vips = &lb->vips;
         struct smap_node *node;
+        int addr_family = AF_INET;
 
         SMAP_FOR_EACH (node, vips) {
             vip_configured = true;
@@ -4674,8 +4675,10 @@ build_pre_lb(struct ovn_datapath *od, struct hmap *lflows,
                 continue;
             }
 
-            if (!sset_contains(&all_ips, ip_address)) {
-                sset_add(&all_ips, ip_address);
+            if (addr_family == AF_INET) {
+                sset_add(&all_ips_v4, ip_address);
+            } else {
+                sset_add(&all_ips_v6, ip_address);
             }
 
             build_empty_lb_event_flow(od, lflows, node, ip_address, lb,
@@ -4694,20 +4697,22 @@ build_pre_lb(struct ovn_datapath *od, struct hmap *lflows,
     /* 'REGBIT_CONNTRACK_DEFRAG' is set to let the pre-stateful table send
      * packet to conntrack for defragmentation. */
     const char *ip_address;
-    SSET_FOR_EACH(ip_address, &all_ips) {
-        char *match;
+    SSET_FOR_EACH (ip_address, &all_ips_v4) {
+        char *match = xasprintf("ip && ip4.dst == %s", ip_address);
+        ovn_lflow_add(lflows, od, S_SWITCH_IN_PRE_LB,
+                      100, match, REGBIT_CONNTRACK_DEFRAG" = 1; next;");
+        free(match);
+    }
 
-        if (addr_family == AF_INET) {
-            match = xasprintf("ip && ip4.dst == %s", ip_address);
-        } else {
-            match = xasprintf("ip && ip6.dst == %s", ip_address);
-        }
+    SSET_FOR_EACH (ip_address, &all_ips_v6) {
+        char *match = xasprintf("ip && ip6.dst == %s", ip_address);
         ovn_lflow_add(lflows, od, S_SWITCH_IN_PRE_LB,
                       100, match, REGBIT_CONNTRACK_DEFRAG" = 1; next;");
         free(match);
     }
 
-    sset_destroy(&all_ips);
+    sset_destroy(&all_ips_v4);
+    sset_destroy(&all_ips_v6);
 
     if (vip_configured) {
         ovn_lflow_add(lflows, od, S_SWITCH_OUT_PRE_LB,