From ad16b754ae2a13d40f2ff24399863449e38d2293 Mon Sep 17 00:00:00 2001
From: morkt <muvluv.ru@gmail.com>
Date: Mon, 17 Jul 2017 11:04:39 +0400
Subject: [PATCH] (PngFormat.ReadMetaData): additional sanity checks.

---
 GameRes/ImagePNG.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/GameRes/ImagePNG.cs b/GameRes/ImagePNG.cs
index 67eaad35..4de63b2d 100644
--- a/GameRes/ImagePNG.cs
+++ b/GameRes/ImagePNG.cs
@@ -129,6 +129,8 @@ namespace GameRes
             meta.Width   = Binary.BigEndian (file.ReadUInt32());
             meta.Height  = Binary.BigEndian (file.ReadUInt32());
             int bpp = file.ReadByte();
+            if (bpp != 1 && bpp != 2 && bpp != 4 && bpp != 8 && bpp != 16)
+                return null;
             int color_type = file.ReadByte();
             switch (color_type)
             {
@@ -136,7 +138,8 @@ namespace GameRes
             case 3: meta.BPP = 24; break;
             case 4: meta.BPP = bpp*2; break;
             case 6: meta.BPP = bpp*4; break;
-            default: meta.BPP = bpp; break;
+            case 0: meta.BPP = bpp; break;
+            default: return null;
             }
             SkipBytes (file, 7);