From: Holger Schemel <info@artsoft.org>
Date: Sat, 27 Aug 2022 08:54:07 +0000 (+0200)
Subject: fixed crash bug when accessing invalid change page for broken level files
X-Git-Tag: 4.3.3.0~72
X-Git-Url: https://git.artsoft.org/?a=commitdiff_plain;h=bfa029317730e611f3f7a687ad679ac92ece898f;p=rocksndiamonds.git

fixed crash bug when accessing invalid change page for broken level files

Thanks to Quipyowert for finding and fixing this bug!
---

diff --git a/src/files.c b/src/files.c
index 09e3b4d2..45f4097f 100644
--- a/src/files.c
+++ b/src/files.c
@@ -3355,6 +3355,10 @@ static int LoadLevel_CUSX(File *file, int chunk_size, struct LevelInfo *level)
 
   while (!checkEndOfFile(file))
   {
+    // level file might contain invalid change page number
+    if (xx_current_change_page >= ei->num_change_pages)
+      break;
+
     struct ElementChangeInfo *change = &ei->change_page[xx_current_change_page];
 
     xx_change = *change;	// copy change data into temporary buffer