From 7aa89e1d09b09d9f5dbb96976ee083a331ab9d71 Mon Sep 17 00:00:00 2001
From: xiaoxiaoafeifei <zhailiangliang@loongson.cn>
Date: Wed, 20 Mar 2024 00:09:05 +0800
Subject: [PATCH] prevent integer overflows in file exrmultipart.cpp (#1681)

Signed-off-by: ZhaiLiangliang <zhailiangliang@loongson.cn>

Origin: https://github.com/AcademySoftwareFoundation/openexr/pull/1681

---
 src/bin/exrmultipart/exrmultipart.cpp | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/bin/exrmultipart/exrmultipart.cpp b/src/bin/exrmultipart/exrmultipart.cpp
index 931cebc..1c624b8 100644
--- a/src/bin/exrmultipart/exrmultipart.cpp
+++ b/src/bin/exrmultipart/exrmultipart.cpp
@@ -326,12 +326,17 @@ convert(vector <const char*> in,
         }
         
         Box2i dataWindow = infile.header(0).dataWindow();
-        int pixel_count = (dataWindow.size().y+1)*(dataWindow.size().x+1);
-        int pixel_width = dataWindow.size().x+1;
-        
+        //
+        // use int64_t for dimensions, since possible overflow int storage
+        //
+        int64_t pixel_count = (static_cast<int64_t>(dataWindow.size ().y) + 1) * (static_cast<int64_t>(dataWindow.size ().x) + 1);
+        int64_t pixel_width = static_cast<int64_t>(dataWindow.size ().x) + 1;
         
+        //
         // offset in pixels between base of array and 0,0
-        int pixel_base = dataWindow.min.y*pixel_width+dataWindow.min.x;
+        // use int64_t for dimensions, since dataWindow.min.y * pixel_width could overflow int storage
+        //
+        int64_t pixel_base = static_cast<int64_t>(dataWindow.min.y) * pixel_width + static_cast<int64_t>(dataWindow.min.x);
 
         vector< vector<char> > channelstore(channel_count);
         
-- 
2.43.0

