stream: fix end-of-stream for HTTP/2

HTTP/2 streams call `.end()` on themselves from their
`.destroy()` method, which might be queued (e.g. due to network
congestion) and not processed before the stream itself is destroyed.

In that case, the `_writableState.ended` property could be set before
the stream emits its `'close'` event, and never actually emits the
`'finished'` event, confusing the end-of-stream implementation so
that it wouldn’t call its callback.

This can be fixed by watching for the end events themselves using the
existing `'finish'` and `'end'` listeners rather than relying on the
`.ended` properties of the `_...State` objects.

These properties still need to be checked to know whether stream
closure was premature – My understanding is that ideally, streams
should not emit `'close'` before `'end'` and/or `'finished'`, so this
might be another bug, but changing this would require modifying tests
and almost certainly be a breaking change.

Fixes: https://github.com/nodejs/node/issues/24456

PR-URL: https://github.com/nodejs/node/pull/24926
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

1 files changed, 14 insertions, 7 deletions

diff --git a/lib/internal/streams/end-of-stream.js b/lib/internal/streams/end-of-stream.js
index 8bbd4827b2..4ad7b93337 100644
--- a/lib/internal/streams/end-of-stream.js
+++ b/lib/internal/streams/end-of-stream.js
@@ -36,8 +36,6 @@ function eos(stream, opts, callback) {
 
   callback = once(callback);
 
-  const ws = stream._writableState;
-  const rs = stream._readableState;
   let readable = opts.readable || (opts.readable !== false && stream.readable);
   let writable = opts.writable || (opts.writable !== false && stream.writable);
 
@@ -45,13 +43,17 @@ function eos(stream, opts, callback) {
     if (!stream.writable) onfinish();
   };
 
+  var writableEnded = stream._writableState && stream._writableState.finished;
   const onfinish = () => {
     writable = false;
+    writableEnded = true;
     if (!readable) callback.call(stream);
   };
 
+  var readableEnded = stream._readableState && stream._readableState.endEmitted;
   const onend = () => {
     readable = false;
+    readableEnded = true;
     if (!writable) callback.call(stream);
   };
 
@@ -60,11 +62,16 @@ function eos(stream, opts, callback) {
   };
 
   const onclose = () => {
-    if (readable && !(rs && rs.ended)) {
-      return callback.call(stream, new ERR_STREAM_PREMATURE_CLOSE());
+    let err;
+    if (readable && !readableEnded) {
+      if (!stream._readableState || !stream._readableState.ended)
+        err = new ERR_STREAM_PREMATURE_CLOSE();
+      return callback.call(stream, err);
     }
-    if (writable && !(ws && ws.ended)) {
-      return callback.call(stream, new ERR_STREAM_PREMATURE_CLOSE());
+    if (writable && !writableEnded) {
+      if (!stream._writableState || !stream._writableState.ended)
+        err = new ERR_STREAM_PREMATURE_CLOSE();
+      return callback.call(stream, err);
     }
   };
 
@@ -77,7 +84,7 @@ function eos(stream, opts, callback) {
     stream.on('abort', onclose);
     if (stream.req) onrequest();
     else stream.on('request', onrequest);
-  } else if (writable && !ws) { // legacy streams
+  } else if (writable && !stream._writableState) { // legacy streams
     stream.on('end', onlegacyfinish);
     stream.on('close', onlegacyfinish);
   }