From 1b5ad743b551b4db5bc72be847887541d0a8fd85 Mon Sep 17 00:00:00 2001
From: Ian Barwick <ian@2ndquadrant.com>
Date: Mon, 11 May 2020 13:52:10 +0900
Subject: [PATCH] standby clone: explicitly set closed connection pointers to
 NULL

We omitted to do this with the connections used when checking the system
identifier, which means libpq calls by the teardown function using the
pointer risk using unallocated memory.

Addresses issue reported in GitHub #644.
---
 repmgr-action-standby.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/repmgr-action-standby.c b/repmgr-action-standby.c
index 3d71e5e8..7e787ee1 100644
--- a/repmgr-action-standby.c
+++ b/repmgr-action-standby.c
@@ -5627,6 +5627,7 @@ check_source_server()
 					{
 						uint64		test_system_identifier = system_identifier(cell->node_info->conn);
 						PQfinish(cell->node_info->conn);
+						cell->node_info->conn = NULL;
 
 						if (test_system_identifier != UNKNOWN_SYSTEM_IDENTIFIER)
 						{
@@ -5650,6 +5651,7 @@ check_source_server()
 					else
 					{
 						PQfinish(cell->node_info->conn);
+						cell->node_info->conn = NULL;
 					}
 				}
 				clear_node_info_list(&all_nodes);