Do not crash on null stream in writing to bidirectional streams

net/spdy/bidirectional_stream_spdy_impl.cc

Index: net/spdy/bidirectional_stream_spdy_impl.cc
diff --git a/net/spdy/bidirectional_stream_spdy_impl.cc b/net/spdy/bidirectional_stream_spdy_impl.cc
index a8531d961a5f1ebeb116d2e6554c3de3c435191b..f8a75c349af2729ae7bfd0926d3860ead8354421 100644
--- a/net/spdy/bidirectional_stream_spdy_impl.cc
+++ b/net/spdy/bidirectional_stream_spdy_impl.cc
@@ -60,7 +60,10 @@ void BidirectionalStreamSpdyImpl::Start(
   timer_ = std::move(timer);
 
   if (!spdy_session_) {
-    delegate_->OnFailed(ERR_CONNECTION_CLOSED);
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(&BidirectionalStreamSpdyImpl::NotifyError,
+                   weak_factory_.GetWeakPtr(), ERR_CONNECTION_CLOSED));
     return;
   }
 
@@ -104,8 +107,15 @@ int BidirectionalStreamSpdyImpl::ReadData(IOBuffer* buf, int buf_len) {
 void BidirectionalStreamSpdyImpl::SendData(const scoped_refptr<IOBuffer>& data,
                                            int length,
                                            bool end_stream) {
-  DCHECK(!stream_closed_);
-  DCHECK(stream_);
+  DCHECK(length > 0 || (length == 0 && end_stream));
+
+  if (!stream_) {
+    LOG(ERROR) << "Trying to send data when stream has been destroyed.";
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&BidirectionalStreamSpdyImpl::NotifyError,
+                              weak_factory_.GetWeakPtr(), ERR_UNEXPECTED));
+    return;
+  }
 
   stream_->SendData(data.get(), length,
                     end_stream ? NO_MORE_DATA_TO_SEND : MORE_DATA_TO_SEND);
@@ -115,10 +125,16 @@ void BidirectionalStreamSpdyImpl::SendvData(
     const std::vector<scoped_refptr<IOBuffer>>& buffers,
     const std::vector<int>& lengths,
     bool end_stream) {
-  DCHECK(!stream_closed_);
-  DCHECK(stream_);
   DCHECK_EQ(buffers.size(), lengths.size());
 
+  if (!stream_) {
+    LOG(ERROR) << "Trying to send data when stream has been destroyed.";
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&BidirectionalStreamSpdyImpl::NotifyError,
+                              weak_factory_.GetWeakPtr(), ERR_UNEXPECTED));
+    return;
+  }
+
   int total_len = 0;
   for (int len : lengths) {
     total_len += len;
@@ -228,7 +244,7 @@ void BidirectionalStreamSpdyImpl::OnClose(int status) {
   stream_.reset();
 
   if (status != OK) {
-    delegate_->OnFailed(status);
+    NotifyError(status);
     return;
   }
   // Complete any remaining read, as all data has been buffered.
@@ -267,6 +283,10 @@ void BidirectionalStreamSpdyImpl::OnStreamInitialized(int rv) {
       return;
     }
   }
+  NotifyError(rv);
+}
+
+void BidirectionalStreamSpdyImpl::NotifyError(int rv) {
   delegate_->OnFailed(rv);
 }