ovn-nbctl: Prevent sync exiting early on nb_cfg overflow

We are correctly wrapping nb_cfg over when the value is LLONG_MAX. However, the sync code is expecting the value to be always raising, so it would exit early as the current >= next is true for the wrap back to 0. To detect that use delta between those two values. The delta threshold is set to INT32_MAX as we don't expect the nb_cfg to be updated more than that during the sync call. Signed-off-by: Ales Musil <[email protected]> Acked-by: Mark Michelson <[email protected]> Signed-off-by: Mark Michelson <[email protected]>
igsilya · Aug 24, 2023 · 7915565 · 7915565
1 parent 2f2324d
commit 7915565
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Showing 2 changed files with 6 additions and 2 deletions.
diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c
@@ -520,7 +520,9 @@ update_sequence_numbers(int64_t loop_start_time,
                              chassis_priv->name);
             }
 
-            if (chassis_priv->nb_cfg < hv_cfg) {
+            /* Detect if overflows happened within the cfg update. */
+            int64_t delta = chassis_priv->nb_cfg - hv_cfg;
+            if (chassis_priv->nb_cfg < hv_cfg || delta > INT32_MAX) {
                 hv_cfg = chassis_priv->nb_cfg;
                 hv_cfg_ts = chassis_priv->nb_cfg_timestamp;
             } else if (chassis_priv->nb_cfg == hv_cfg &&

diff --git a/utilities/ovn-nbctl.c b/utilities/ovn-nbctl.c
@@ -122,7 +122,9 @@ nbctl_post_execute(struct ovsdb_idl *idl, struct ovsdb_idl_txn *txn,
             int64_t cur_cfg = (wait_type == NBCTL_WAIT_SB
                                ? nb->sb_cfg
                                : MIN(nb->sb_cfg, nb->hv_cfg));
-            if (cur_cfg >= next_cfg) {
+            /* Detect if overflows happened within the cfg update. */
+            int64_t delta = cur_cfg - next_cfg;
+            if (cur_cfg >= next_cfg && delta < INT32_MAX) {
                 if (print_wait_time) {
                     printf("Time spent on processing nb_cfg %"PRId64":\n",
                            next_cfg);