diff options
| author | Tatsuo Ishii | 2024-06-21 05:21:15 +0000 |
|---|---|---|
| committer | Tatsuo Ishii | 2024-06-21 05:21:15 +0000 |
| commit | d699b8f129c70f434c525208b58bcc09da36f3a3 (patch) | |
| tree | f78d8bfb37c28b8759a55d3b24c16bd5d0620de7 /src | |
| parent | d6f5b11516887088cbfe3ca6aa712f529b01b6c9 (diff) | |
Fix MAIN_NODE macro (actually pool_virtual_main_db_node_id()).
The macro used to REAL_MAIN_NODE_ID if there's no session context.
This is wrong since REAL_MAIN_NODE_ID can be changed any time when
failover/failback happens. Suppose REAL_MAIN_NODE_ID ==
my_main_node_id == 1. Then due to failback, REAL_MAIN_NODE_ID is
changed to 0. Then MAIN_CONNECTION(cp) will return NULL and any
reference to it will cause segmentation fault. To prevent the issue we
should return my_main_node_id instead.
Discussion: https://www.pgpool.net/pipermail/pgpool-general/2024-June/009205.html
Backpatch-through: V4.1
Diffstat (limited to 'src')
| -rw-r--r-- | src/context/pool_query_context.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/src/context/pool_query_context.c b/src/context/pool_query_context.c index ed055ec88..f484b77a7 100644 --- a/src/context/pool_query_context.c +++ b/src/context/pool_query_context.c @@ -376,7 +376,16 @@ pool_virtual_main_db_node_id(void) sc = pool_get_session_context(true); if (!sc) { - return REAL_MAIN_NODE_ID; + /* + * We used to return REAL_MAIN_NODE_ID here. Problem with it is, it + * is possible that REAL_MAIN_NODE_ID could be changed + * anytime. Suppose REAL_MAIN_NODE_ID == my_main_node_id == 1. Then + * due to failback, REAL_MAIN_NODE_ID is changed to 0. Then + * MAIN_CONNECTION(cp) will return NULL and any reference to it will + * cause segmentation fault. To prevent the issue we should return + * my_main_node_id instead. + */ + return my_main_node_id; } if (sc->in_progress && sc->query_context) |