From 63e8c5730918b5e7d4dda7b08b575e9ee568a29d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Javier=20Jaramago=20Fern=C3=A1ndez?=
 <jaramago.fernandez.javier@gmail.com>
Date: Mon, 18 Jul 2022 19:36:36 +0200
Subject: [PATCH] Fix invalid memory accesses in Aurora monitoring

Invalid memory accesses could take place if no servers can be pinged.
---
 lib/MySQL_Monitor.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/MySQL_Monitor.cpp b/lib/MySQL_Monitor.cpp
index 6527c54ca..ab8f8d875 100644
--- a/lib/MySQL_Monitor.cpp
+++ b/lib/MySQL_Monitor.cpp
@@ -4294,6 +4294,11 @@ void * monitor_AWS_Aurora_thread_HG(void *arg) {
 			cur_host_idx++;
 		}
 	}
+	// NOTE: 'cur_host_idx' should never be higher than 'num_hosts' otherwise later an invalid memory access
+	// can table place later when accessing 'hpa[cur_host_idx]'.
+	if (cur_host_idx >= num_hosts) {
+		cur_host_idx = num_hosts - 1;
+	}
 	pthread_mutex_unlock(&GloMyMon->aws_aurora_mutex);
 
 	bool exit_now = false;