Stream only partially read when downloading object from Amazon AWS S3

I am trying to simply download an object from my bucket using C# just like we can find in S3 examples, and I can't figure out why the stream won't be entirely copied to my byte array. Only the first 8192 bytes are copied instead of the whole stream.

I have tried with with an Amazon.S3.AmazonS3Client and with an Amazon.S3.Transfer.TransferUtility, but in both cases only the first bytes are actually copied into the buffer.

var stream = await _transferUtility.OpenStreamAsync(BucketName, key);
using (stream)
{
    byte[] content = new byte[stream.Length];
    stream.Read(content, 0, content.Length);
    // Here content should contain all the data from the stream, but only the first 8192 bytes are actually populated.
}

When debugging, I see the stream type is Amazon.Runtime.Internal.Util.Md5Stream, and inside the stream, before calling Read() the property CurrentPosition = 0. After the call, CurrentPosition becomes 8192, which seems to indeed indicate only the first 8K of data was read. The total Length of the stream is 104042.

If I make more calls to stream.Read(), I see more data gets read and CurrentPosition increases in value. But CurrentPosition is not a public property, and I cannot access it in my code to make a while() loop (and having to code such loops to read all the data seems a bit clunky).

Why are only the first 8K read in my code? How should I proceed to read the entire stream?

I tried calling stream.Flush(), but it did not fix the problem.

EDIT 1

I have modified my code so it does the following:

var stream = await _transferUtility.OpenStreamAsync(BucketName, key);
using (stream)
{
    byte[] content = new byte[stream.Length];
    var bytesRead = 0;

    while (bytesRead < stream.Length)
        bytesRead += stream.Read(content, bytesRead, content.Length - bytesRead);
}

And it works. But still looks clunky. Is it normal I have to do this?

EDIT 2

Final solution is to create a MemoryStream of the correct size and then call CopyTo(). So no clunky loop anymore and no risk of infinite loop if Read() starts returning 0 before the whole stream has been read:

var stream = await _transferUtility.OpenStreamAsync(BucketName, key);
using (stream)
{
    using (var memoryStream = new MemoryStream((int)stream.Length))
    {
        stream.CopyTo(memoryStream);
        var myBuffer = memoryStream.GetBuffer();
    }
}