Mark Eichin submitted bug report #1480821

(http://curl.haxx.se/bug/view.cgi?id=1480821) He found and identified a
problem with how libcurl dealt with GnuTLS and a case where gnutls returned
GNUTLS_E_AGAIN indicating it would block. It would then return an unexpected
return code, making Curl_ssl_send() confuse the upper layer - causing random
28 bytes trash data to get inserted in the transfered stream.

The proper fix was to make the Curl_gtls_send() function return the proper
return codes that the callers would expect. The Curl_ossl_send() function
already did this.

RELEASE-NOTES

@@ -20,6 +20,7 @@ This release includes the following changes:
 
 This release includes the following bugfixes:
 
+ o GnuTLS non-block case that could cause data trashing
  o deflate code survives lack of zlib header
  o CURLOPT_INTERFACE works with hostname
  o configure runs fine with ICC
@@ -46,6 +47,6 @@ advice from friends like these:
 
  Dan Fandrich, Ilja van Sprundel, David McCreedy, Tor Arntsen, Xavier Bouchoux,
  David Byron, Michele Bini, Ates Goral, Katie Wang, Robson Braga Araujo,
- Ale Vesely, Paul Querna, Gisle Vanem
+ Ale Vesely, Paul Querna, Gisle Vanem, Mark Eichin
 
         Thanks! (and sorry if I forgot to mention someone)