From 3709eda2701d53623732c7c7ccebf84a0ab4f37d Mon Sep 17 00:00:00 2001
From: James Newton-King <james@newtonking.com>
Date: Wed, 8 Jul 2020 13:41:23 +1200
Subject: [PATCH] Fix HTTP/2 stream output flow control abort error (#23727)

* Fix stream output flow control abort error

* Clean up

* Clean up

* Add timeouts
---
 .../FlowControl/StreamOutputFlowControl.cs    |  2 +-
 .../Http2/Http2ConnectionTests.cs             | 62 +++++++++++++++++++
 2 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/src/Servers/Kestrel/Core/src/Internal/Http2/FlowControl/StreamOutputFlowControl.cs b/src/Servers/Kestrel/Core/src/Internal/Http2/FlowControl/StreamOutputFlowControl.cs
index 792a1ca3a7..f688e5669e 100644
--- a/src/Servers/Kestrel/Core/src/Internal/Http2/FlowControl/StreamOutputFlowControl.cs
+++ b/src/Servers/Kestrel/Core/src/Internal/Http2/FlowControl/StreamOutputFlowControl.cs
@@ -94,7 +94,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http2.FlowControl
             if (_currentConnectionLevelAwaitable != null &&
                 _currentConnectionLevelAwaitable.Version == _currentConnectionLevelAwaitableVersion)
             {
-                _currentConnectionLevelAwaitable.SetResult(null);
+                _currentConnectionLevelAwaitable.TrySetResult(null);
             }
         }
 
diff --git a/src/Servers/Kestrel/test/InMemory.FunctionalTests/Http2/Http2ConnectionTests.cs b/src/Servers/Kestrel/test/InMemory.FunctionalTests/Http2/Http2ConnectionTests.cs
index a1cf418fe3..a969bfe609 100644
--- a/src/Servers/Kestrel/test/InMemory.FunctionalTests/Http2/Http2ConnectionTests.cs
+++ b/src/Servers/Kestrel/test/InMemory.FunctionalTests/Http2/Http2ConnectionTests.cs
@@ -1594,6 +1594,68 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
             await WaitForAllStreamsAsync();
         }
 
+        [Fact]
+        public async Task OutputFlowControl_ConnectionAndRequestAborted_NoException()
+        {
+            // Ensure the stream window size is bigger than the connection window size
+            _clientSettings.InitialWindowSize = _clientSettings.InitialWindowSize * 2;
+
+            var connectionAbortedTcs = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);
+            var requestAbortedTcs = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);
+
+            await InitializeConnectionAsync(async context =>
+            {
+                // Exceed connection window size
+                await context.Response.WriteAsync(new string('!', 65536));
+
+                await connectionAbortedTcs.Task;
+
+                try
+                {
+                    context.Abort();
+                    requestAbortedTcs.SetResult();
+                }
+                catch (Exception ex)
+                {
+                    requestAbortedTcs.SetException(ex);
+                }
+            }).DefaultTimeout();
+
+            await StartStreamAsync(1, _browserRequestHeaders, endStream: true).DefaultTimeout();
+
+            await ExpectAsync(Http2FrameType.HEADERS,
+                withLength: 32,
+                withFlags: (byte)(Http2HeadersFrameFlags.END_HEADERS),
+                withStreamId: 1).DefaultTimeout();
+
+            await ExpectAsync(Http2FrameType.DATA,
+                withLength: 16384,
+                withFlags: (byte)(Http2DataFrameFlags.NONE),
+                withStreamId: 1).DefaultTimeout();
+
+            await ExpectAsync(Http2FrameType.DATA,
+                withLength: 16384,
+                withFlags: (byte)(Http2DataFrameFlags.NONE),
+                withStreamId: 1).DefaultTimeout();
+
+            await ExpectAsync(Http2FrameType.DATA,
+                withLength: 16384,
+                withFlags: (byte)(Http2DataFrameFlags.NONE),
+                withStreamId: 1).DefaultTimeout();
+
+            await ExpectAsync(Http2FrameType.DATA,
+                withLength: 16383,
+                withFlags: (byte)(Http2DataFrameFlags.NONE),
+                withStreamId: 1).DefaultTimeout();
+
+            _connection.HandleReadDataRateTimeout();
+
+            connectionAbortedTcs.SetResult();
+
+            // Task completing successfully means HttpContext.Abort didn't throw
+            await requestAbortedTcs.Task.DefaultTimeout();
+        }
+
         [Fact]
         public async Task DATA_Sent_DespiteStreamOutputFlowControl_IfEmptyAndEndsStream()
         {