Cannot access 4 GB or bigger files through the ProjFS driver

There seem to be an arithmetic overflow somewhere. The IVirtualizationInstance.OnGetFileStream (from ProjectedFSLib.Managed.dll) callback is invoked with:

• for a 4 GB file: a byteOffset of 0 and length of 0
• for a 4 GB file + 1 byte: a byteOffset of 0 and length of 1
• for a 4 GB file - 1 byte: a byteOffset of 0 and length of 4294967295

Steps to reproduce:

1. Build the MirrorProvider by running MirrorProvider\Scripts\Windows\Build.bat.
2. Create a C:\PathToMirror folder.
3. Generate a 4 GB file, for exemple by running the following Python code:

   with open('C:\\PathToMirror\\huge_file_4GB.bin', 'wb') as f:
       f.seek(4*1024*1024*1024 - 1)
       f.write(b"\0")
   

4. Clone and mount the MirrorProvider by running MirrorProvider\Scripts\Windows\MirrorProvider_Clone.bat and then MirrorProvider\Scripts\Windows\MirrorProvider_Mirror.bat.
5. Open and read data from the mirrored file C:\TestRoot\src\huge_file_4GB.bin, for exemple by running the following Python code:

   with open('C:\\TestRoot\\src\\huge_file_4GB.bin', 'rb') as f:
       something = f.read(1)
   

6. Notice the following failure in the MirrorProvider output:

   GetPlaceholderInformation: `huge_file_4GB.bin`
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   GetFileStream: `huge_file_4GB.bin`
   WriteFile faild: -2147024362
   

   Note that the -2147024362 HResult is E_ARITHMETIC_OVERFLOW.

Start by reproducing the issue with MirrorProvider\Scripts\Windows\Build.bat, MirrorProvider_Clone.bat, and MirrorProvider_Mirror.bat, then inspect IVirtualizationInstance.OnGetFileStream and the MirrorProvider output. Compare byteOffset and length for files around 4 GB and trace where the arithmetic overflow produces E_ARITHMETIC_OVERFLOW. Done means reads from 4 GB and larger files succeed without overflow.