Large dataWindow Offset test: for discussion

OpenEXR/IlmImf/ImfHeader.cpp

@@ -802,22 +802,6 @@ Header::sanityCheck (bool isTiled, bool isMultipartFile) const
 			    "maximum height of " << maxImageHeight << "pixels.");
     }
 
-    // make sure to avoid simple math overflow for large offsets
-    // we know we're at a positive width because of checks above
-    long long bigW = static_cast<long long>( w );
-    long long absOffY = std::abs ( dataWindow.min.y );
-    long long absOffX = std::abs ( dataWindow.min.x );
-    long long offX = static_cast<long long>( INT_MAX ) - absOffX;
-    long long offsetCount = absOffY * bigW;
-    long long bytesLeftPerLine = static_cast<long long>( INT_MAX ) / bigW;
-    if (bytesLeftPerLine < absOffY || offX < offsetCount)
-    {
-	THROW (IEX_NAMESPACE::ArgExc, "Data window [ (" << dataWindow.min.x
-	       << ", " << dataWindow.min.x << ") - (" << dataWindow.max.x
-	       << ", " << dataWindow.max.x
-	       << ") ] offset / size will overflow pointer calculations");
-    }
-
     // chunk table must be smaller than the maximum image area
     // (only reachable for unknown types or damaged files: will have thrown earlier
     //  for regular image types)

OpenEXR/IlmImfTest/CMakeLists.txt

@@ -59,6 +59,7 @@ add_executable(IlmImfTest
   testWav.cpp
   testXdr.cpp
   testYca.cpp
+  testLargeDataWindowOffsets.cpp
 )
 target_compile_definitions(IlmImfTest PRIVATE ILM_IMF_TEST_IMAGEDIR="${CMAKE_CURRENT_SOURCE_DIR}/")
 target_link_libraries(IlmImfTest OpenEXR::IlmImf)

OpenEXR/IlmImfTest/Makefile.am

@@ -56,6 +56,7 @@ IlmImfTest_SOURCES = main.cpp tmpDir.h testAttributes.cpp testChannels.cpp \
 		     testFutureProofing.cpp testFutureProofing.h \
 	             compareDwa.cpp compareDwa.h \
 	             testDwaCompressorSimd.cpp testDwaCompressorSimd.h \
+  	             testLargeDataWindowOffsets.cpp testLargeDataWindowOffsets.h \
 	             testRle.cpp testRle.h \
 		     bswap_32.h
 

OpenEXR/IlmImfTest/main.cpp

@@ -63,6 +63,7 @@
 #include "testYca.h"
 #include "testTiledYa.h"
 #include "testIsComplete.h"
+#include "testLargeDataWindowOffsets.h"
 #include "testSharedFrameBuffer.h"
 #include "testMultiView.h"
 #include "testMultiPartApi.h"
@@ -155,6 +156,7 @@ main (int argc, char *argv[])
     TEST (testHuf, "core");
     TEST (testWav, "core");
     TEST (testRgba, "basic");
+    TEST (testLargeDataWindowOffsets, "basic");
     TEST (testSharedFrameBuffer, "basic");
     TEST (testRgbaThreading, "basic");
     TEST (testChannels, "basic");