Comment 2 for bug 480849

You write that the "Samba daemon crashes" in your title, what do you mean by that ? One of the nmdd/smbd process segfaults ? Anything in the samba logs (/var/log/samba ?). If it's just that the file transfer appears to freeze and CPU use rises to 100%, then it's not really a "crash".

In the latter case, I wouldn't be surprised if load was up 100% when encrypting a 9Gb file and took what would appear forever. You mention copying smaller files with success. Could you please gradually try to increase file size and see what happens ?