controller: Prevent crash when db is empty.

ovn-controller crashed when connected to an empty local db, forcing the user to initialize a local db before starting the controller daemon. With this fix, the controller will no longer crash in this case, but instead keep running and wait until the database is initialized to do anything else. Reported-at: https://issues.redhat.com/browse/FDP-715 Signed-off-by: Rosemarie O'Riorden <[email protected]> Acked-by: Ilya Maximets <[email protected]> Signed-off-by: Dumitru Ceara <[email protected]>
almusil · Dec 2, 2024 · de3600f · de3600f
1 parent cfcf345
commit de3600f
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Showing 3 changed files with 32 additions and 4 deletions.
diff --git a/controller/chassis.c b/controller/chassis.c
@@ -1024,6 +1024,9 @@ store_chassis_index_if_needed(
 {
     const struct ovsrec_open_vswitch *cfg =
         ovsrec_open_vswitch_table_first(ovs_table);
+    if (!cfg) {
+        return;
+    }
     const char *chassis_id = get_ovs_chassis_id(ovs_table);
 
     char *idx_key = xasprintf(CHASSIS_IDX_PREFIX "%s", chassis_id);

diff --git a/controller/ovn-controller.c b/controller/ovn-controller.c
@@ -5527,6 +5527,8 @@ main(int argc, char *argv[])
             ovsrec_open_vswitch_table_get(ovs_idl_loop.idl);
         const struct ovsrec_bridge *br_int = NULL;
         const struct ovsrec_datapath *br_int_dp = NULL;
+        const struct ovsrec_open_vswitch *cfg =
+            ovsrec_open_vswitch_table_first(ovs_table);
         process_br_int(ovs_idl_txn, bridge_table, ovs_table, &br_int,
                        ovsrec_server_has_datapath_table(ovs_idl_loop.idl)
                        ? &br_int_dp
@@ -5538,9 +5540,7 @@ main(int argc, char *argv[])
                               br_int_remote.probe_interval);
 
         /* Enable ACL matching for double tagged traffic. */
-        if (ovs_idl_txn) {
-            const struct ovsrec_open_vswitch *cfg =
-                ovsrec_open_vswitch_table_first(ovs_table);
+        if (ovs_idl_txn && cfg) {
             int vlan_limit = smap_get_int(
                 &cfg->other_config, "vlan-limit", -1);
             if (vlan_limit != 0) {
@@ -5556,7 +5556,7 @@ main(int argc, char *argv[])
         }
 
         if (ovsdb_idl_has_ever_connected(ovnsb_idl_loop.idl) &&
-            northd_version_match) {
+            northd_version_match && cfg) {
 
             /* Unconditionally remove all deleted lflows from the lflow
              * cache.

diff --git a/tests/ovn-controller.at b/tests/ovn-controller.at
@@ -3419,3 +3419,28 @@ AT_CHECK([test $(grep -c "HANDLER_MESSAGE" hv1/ovn-controller.log) -ge 1])
 
 OVN_CLEANUP([hv1])
 AT_CLEANUP
+
+AT_SETUP([ovn-controller - Start controller with empty db])
+AT_KEYWORDS([ovn])
+
+check ovsdb-tool create conf.db $ovs_srcdir/vswitchd/vswitch.ovsschema
+start_daemon ovsdb-server --remote=punix:db.sock
+start_daemon ovn-controller unix:db.sock
+
+AT_CHECK([ovsdb-client --bare dump unix:db.sock Open_vSwitch Open_vSwitch], [], [dnl
+Open_vSwitch table
+])
+check ovs-vsctl --no-wait init
+OVS_WAIT_FOR_OUTPUT([ovs-vsctl show | tail -n +2], [], [dnl
+    Bridge br-int
+        fail_mode: secure
+        datapath_type: system
+        Port br-int
+            Interface br-int
+                type: internal
+])
+
+# Gracefully terminate daemons.
+OVS_APP_EXIT_AND_WAIT([ovn-controller])
+OVS_APP_EXIT_AND_WAIT([ovsdb-server])
+AT_CLEANUP