GZipStream : Enforcing strict validation to detect truncated gzip files [.NET 9]

[ali-mazloum]

.NET Version : 9.0

I'm working on a way to detect and process gzip files that may get corrupted somewhere in the environment, and was looking at using the .NET library GZipStream as such :

try
{
  using (var fileStream = file.OpenRead())
  using (var gzipStream = new GZipStream(fileStream, CompressionMode.Decompress))
  using (var reader = new StreamReader(gzipStream))
  {
     decompressedContent = reader.ReadToEnd();
  }
        
  return false;
}

catch(Exception ex)
{
  return true;
}

This works fine in most cases, but it doesn't seem as strict as other libraries when it comes to validating truncated files. For example, if I have a gzip file truncated halfway that is generated as such:

cat > sample.txt <<'TXT'
{message:"some data"}
{message:"some data"}
TXT
gzip -c sample.txt > my_valid_gzip.gz

size=$(stat -c%s my_valid_gzip.gz)
half=$((size/2))
head -c "$half" valid.gz > truncated_half.gz

then the GZipStream library does not throw any exception, but a command such as gunzip -t fails due to truncated data. The same can be observed if we generate a GZ file with the last 8 bytes removed (CRC + ISize)

Is there a way to enforce strict validation using GZipStream that would be the equivalent of say the command gunzip -t on unix systems?

I saw other discussions around changing the GZipStream API to add strict validation, but it looks like it was later reversed, then put back in .NET8 , but I'm not sure if this covers the same case : #75671