From 77d4573d9bd6305c9c8e3919367fd280f5343b70 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Sat, 29 Jul 2017 00:10:43 +0700
Subject: [PATCH] return an error when Write is called on a closed stream

---
 stream.go      | 3 +++
 stream_test.go | 6 ++++++
 2 files changed, 9 insertions(+)

diff --git a/stream.go b/stream.go
index 6a3d4a06f..45cf01a16 100644
--- a/stream.go
+++ b/stream.go
@@ -180,6 +180,9 @@ func (s *stream) Write(p []byte) (int, error) {
 	if s.resetLocally.Get() || s.err != nil {
 		return 0, s.err
 	}
+	if s.finishedWriting.Get() {
+		return 0, fmt.Errorf("write on closed stream %d", s.streamID)
+	}
 	if len(p) == 0 {
 		return 0, nil
 	}
diff --git a/stream_test.go b/stream_test.go
index 892530967..d14900b53 100644
--- a/stream_test.go
+++ b/stream_test.go
@@ -865,6 +865,12 @@ var _ = Describe("Stream", func() {
 				Expect(str.finishedWriting.Get()).To(BeTrue())
 			})
 
+			It("doesn't allow writes after it has been closed", func() {
+				str.Close()
+				_, err := strWithTimeout.Write([]byte("foobar"))
+				Expect(err).To(MatchError("write on closed stream 1337"))
+			})
+
 			It("allows FIN", func() {
 				str.Close()
 				Expect(str.shouldSendFin()).To(BeTrue())