From 4293c36cb91229a2b18308f48d778919e2fe6ddc Mon Sep 17 00:00:00 2001
From: Alexander Entinger <cto@lxrobotics.com>
Date: Wed, 20 Jan 2021 17:57:08 +0100
Subject: [PATCH] Prevent array-out-of-bounds access.

---
 src/ArduinoNmeaParser.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/ArduinoNmeaParser.cpp b/src/ArduinoNmeaParser.cpp
index e25eceb..b9b1cd0 100644
--- a/src/ArduinoNmeaParser.cpp
+++ b/src/ArduinoNmeaParser.cpp
@@ -106,6 +106,9 @@ void ArduinoNmeaParser::flushParserBuffer()
 
 bool ArduinoNmeaParser::isCompleteNmeaMessageInParserBuffer()
 {
+  if (_parser_buf_elems < 2)
+    return false;
+
   char const prev_last = _parser_buf[_parser_buf_elems - 2];
   char const      last = _parser_buf[_parser_buf_elems - 1];