Fix instability in SSL client/server sockets

net/socket/ssl_client_socket_nss.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file includes code SSLClientSocketNSS::DoVerifyCertComplete() derived
 // from AuthCertificateCallback() in
 // mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp.
 
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
@@ skipping 1716 matching lines @@
 }
 
 void SSLClientSocketNSS::UncorkAfterTimeout() {
   corked_ = false;
   int nsent;
   do {
     nsent = BufferSend();
   } while (nsent > 0);
 }
 
-// Do network I/O between the given buffer and the given socket.
-// Return true if some I/O performed, false otherwise (error or ERR_IO_PENDING)
+// Do as much as possible network I/O between the buffer and the
+// transport socket. Return true if some I/O performed, false
+// otherwise (error or ERR_IO_PENDING).
 bool SSLClientSocketNSS::DoTransportIO() {
   EnterFunction("");
   bool network_moved = false;
   if (nss_bufs_ != NULL) {
-    int nsent = BufferSend();
-    int nreceived = BufferRecv();
-    network_moved = (nsent > 0 || nreceived >= 0);
+    int rv;
+    // Read and write as much data as we can. Loops are neccessary
+    // because Read() and Write() may return synchronously.
+    do {
+      rv = BufferSend();
+      if (rv > 0)
+        network_moved = true;
+    } while (rv > 0);
+    do {
+      rv = BufferRecv();
+      if (rv >= 0)
+        network_moved = true;
+    } while (rv > 0);
   }
   LeaveFunction(network_moved);
   return network_moved;
 }
 
 // Return 0 for EOF,
 // > 0 for bytes transferred immediately,
 // < 0 for error (or the non-error ERR_IO_PENDING).
 int SSLClientSocketNSS::BufferSend(void) {
   if (transport_send_busy_)
@@ skipping 513 matching lines @@
   valid_thread_id_ = base::PlatformThread::CurrentId();
 }
 
 bool SSLClientSocketNSS::CalledOnValidThread() const {
   EnsureThreadIdAssigned();
   base::AutoLock auto_lock(lock_);
   return valid_thread_id_ == base::PlatformThread::CurrentId();
 }
 
 }  // namespace net