From dae3f159a10a3499ef001fddd52e6cd1949927be Mon Sep 17 00:00:00 2001
From: Dumitru Ceara <dceara@redhat.com>
Date: Thu, 18 Feb 2021 17:42:58 +0100
Subject: [PATCH 1/2] binding: Fix potential crash when binding_seqno_run is
 skipped.

The prerequisite for binding_seqno_run() is that it has to be called
while there are valid SB and OVS transactions available.

ovn-controller's main() function respects that but that means that there
is a small window (when OVS transaction is still in progress) when port
bindings might be deleted from the Southbound.

When binding_seqno_run() was finally called, it was asserting that the
Port_bindings to still exist.  This check is too restrictive and the
solution is to just skip bindings that have become partial (i.e., no
SB.Port_Binding or no OVS.Interface).

Fixes: 4d3cb42b076b ("binding: Set Logical_Switch_Port.up when all OVS flows are installed.")
Reported-at: https://bugzilla.redhat.com/1930030
Reported-by: Numan Siddique <numans@ovn.org>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Numan Siddique <numans@ovn.org>

(cherry-picked from upstream master commit d7eeb01db61e72a1be8796480de2a1c8da455d42)

Change-Id: I0cd933a7e062e72cc1fea3515ddcf31430dc5224
---
 controller/binding.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/controller/binding.c b/controller/binding.c
index efaa109d5..2b19fd0e9 100644
--- a/controller/binding.c
+++ b/controller/binding.c
@@ -2498,13 +2498,15 @@ binding_seqno_run(struct shash *local_bindings)
     SSET_FOR_EACH_SAFE (iface_id, iface_id_next, &binding_iface_bound_set) {
         struct shash_node *lb_node = shash_find(local_bindings, iface_id);
 
-        if (lb_node) {
-            /* This is a newly bound interface, make sure we reset the
-             * Port_Binding 'up' field and the OVS Interface 'external-id'.
-             */
-            struct local_binding *lb = lb_node->data;
+        struct local_binding *lb = lb_node ? lb_node->data : NULL;
 
-            ovs_assert(lb->pb && lb->iface);
+        /* Make sure the binding is still complete, i.e., both SB port_binding
+         * and OVS interface still exist.
+         *
+         * If so, then this is a newly bound interface, make sure we reset the
+         * Port_Binding 'up' field and the OVS Interface 'external-id'.
+         */
+        if (lb && lb->pb && lb->iface) {
             new_ifaces = true;
 
             if (smap_get(&lb->iface->external_ids, OVN_INSTALLED_EXT_ID)) {
-- 
2.29.2