Prevent overflow in getScanlineChunkOffsetTableSize (#1003)

Signed-off-by: Peter Hillman <peterh@wetafx.co.nz> Signed-off-by: Cary Phillips <cary@ilm.com>
AcademySoftwareFoundation · May 17, 2021 · 087fa6c · 087fa6c
1 parent 107922e
commit 087fa6c
Showing 1 changed file with 8 additions and 3 deletions.
diff --git a/src/lib/OpenEXR/ImfMisc.cpp b/src/lib/OpenEXR/ImfMisc.cpp
@@ -1828,12 +1828,17 @@ getScanlineChunkOffsetTableSize(const Header& header)
 {
     const Box2i &dataWindow = header.dataWindow();
 
-    int linesInBuffer = numLinesInBuffer ( header.compression() );
 
-    int lineOffsetSize = (dataWindow.max.y - dataWindow.min.y +
+    //
+    // use int64_t types to prevent overflow in lineOffsetSize for images with
+    // extremely high dataWindows
+    //
+    int64_t linesInBuffer = numLinesInBuffer ( header.compression() );
+
+    int64_t lineOffsetSize = (static_cast <int64_t>(dataWindow.max.y) - static_cast <int64_t>(dataWindow.min.y) +
                           linesInBuffer) / linesInBuffer;
 
-    return lineOffsetSize;
+    return static_cast <int>(lineOffsetSize);
 }
 
 //