From 53ba375fbf20d62bb6feec7dac2036035367d7ab Mon Sep 17 00:00:00 2001
From: Chuck Walbourn <walbourn@users.noreply.github.com>
Date: Wed, 8 Nov 2023 18:20:40 -0800
Subject: [PATCH] texconv: Fix PPM reader to avoid overread of buffer (#410)

---
 .gitignore                 | 1 +
 Texconv/PortablePixMap.cpp | 9 +++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/.gitignore b/.gitignore
index 56c7697..8e9cf76 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,6 +34,7 @@ Profile
 Release
 x64
 /Tests
+/Testing
 /wiki
 /out
 /CMakeUserPresets.json
diff --git a/Texconv/PortablePixMap.cpp b/Texconv/PortablePixMap.cpp
index f5b4d8d..870bba8 100644
--- a/Texconv/PortablePixMap.cpp
+++ b/Texconv/PortablePixMap.cpp
@@ -202,16 +202,17 @@ HRESULT __cdecl LoadFromPortablePixMap(
 
             while (ppmSize > 0 && (pixels < pixelEnd))
             {
+                if (ppmSize < 3)
+                {
+                    return HRESULT_FROM_WIN32(ERROR_HANDLE_EOF);
+                }
+
                 *pixels++ = (255 * pData[0] / max)
                     | ((255 * pData[1] / max) << 8)
                     | ((255 * pData[2] / max) << 16)
                     | 0xff000000;
 
                 pData += 3;
-                if (ppmSize < 3)
-                {
-                    return HRESULT_FROM_WIN32(ERROR_HANDLE_EOF);
-                }
                 ppmSize -= 3;
             }