From c112cdde893c8c67a5c3369b31a5693e9b1c13f6 Mon Sep 17 00:00:00 2001
From: helixhorned <helixhorned@1a8010ca-5511-0410-912e-c29ae57300e0>
Date: Fri, 9 Dec 2011 19:09:14 +0000
Subject: [PATCH] Fix a potential out-of-bounds read and write when loading the
 help file in Mapster32.

git-svn-id: https://svn.eduke32.com/eduke32@2161 1a8010ca-5511-0410-912e-c29ae57300e0
---
 polymer/eduke32/source/astub.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/polymer/eduke32/source/astub.c b/polymer/eduke32/source/astub.c
index 39f771940..1a1093c9e 100644
--- a/polymer/eduke32/source/astub.c
+++ b/polymer/eduke32/source/astub.c
@@ -2018,7 +2018,8 @@ static void ReadHelpFile(const char *name)
             if (charsread>0)
             {
                 tempbuf[charsread-1]=0;
-                if (tempbuf[charsread-2]==0x0d) tempbuf[charsread-2]=0;
+                if (charsread>=2 && tempbuf[charsread-2]==0x0d)
+                    tempbuf[charsread-2]=0;
             }
 
             Bmemcpy(hp->line[j], tempbuf, 80);