SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException fails with "A QUIC protocol error was encountered."

[jkotas]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1082667
Build error leg or test failing: System.Net.Http.Functional.Tests.SocketsHttpHandlerTest_HttpClientHandlerTest_Http3.SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException
Pull request: #117051

Error Message

Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": ["SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException","Failure: Sub-string not found","A QUIC protocol error was encountered.","ASCII"],
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1082667
Error message validated: [SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException Failure: Sub-string not found A QUIC protocol error was encountered. ASCII]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 7/1/2025 8:12:00 PM UTC

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[jkotas]

Log snippet:

    System.Net.Http.Functional.Tests.SocketsHttpHandlerTest_HttpClientHandlerTest_Http3.SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException(dangerousChar: 'A', headerType: Cookie) [FAIL]
      Assert.Contains() Failure: Sub-string not found
      String:    "A QUIC protocol error was encountered."
      Not found: "ASCII"
      Stack Trace:
        /_/src/libraries/Common/tests/System/Net/Http/HttpClientHandlerTest.cs(2222,0): at System.Net.Http.Functional.Tests.HttpClientHandlerTest.SendAsync_RequestWithDangerousControlHeaderValue_ThrowsHttpRequestException(Char dangerousChar, HeaderType headerType)
        --- End of stack trace from previous location ---
      Output:
        System.Net.Http.HttpRequestException: A QUIC protocol error was encountered. (example.com:443)
         ---> System.Net.Quic.QuicException: A QUIC protocol error was encountered.
           at System.Net.Quic.QuicConnection.HandleEventShutdownInitiatedByTransport(_SHUTDOWN_INITIATED_BY_TRANSPORT_e__Struct& data) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 653
           at System.Net.Quic.QuicConnection.HandleConnectionEvent(QUIC_CONNECTION_EVENT& connectionEvent) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 767
           at System.Net.Quic.QuicConnection.NativeCallback(QUIC_HANDLE* connection, Void* context, QUIC_CONNECTION_EVENT* connectionEvent) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 802
        --- End of stack trace from previous location ---
           at System.Net.Quic.ValueTaskSource.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/Internal/ValueTaskSource.cs:line 176
           at System.Net.Quic.QuicConnection.FinishConnectAsync(QuicClientConnectionOptions options, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 448
           at System.Net.Quic.QuicConnection.<ConnectAsync>g__StartConnectAsync|2_0(QuicClientConnectionOptions options, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 85
           at System.Net.Quic.QuicConnection.<ConnectAsync>g__StartConnectAsync|2_0(QuicClientConnectionOptions options, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Quic/src/System/Net/Quic/QuicConnection.cs:line 100
           at System.Net.Http.ConnectHelper.ConnectQuicAsync(HttpRequestMessage request, DnsEndPoint endPoint, TimeSpan idleTimeout, SslClientAuthenticationOptions clientAuthenticationOptions, Action`2 streamCapacityCallback, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectHelper.cs:line 121
           --- End of inner exception stack trace ---
           at System.Net.Http.ConnectHelper.ConnectQuicAsync(HttpRequestMessage request, DnsEndPoint endPoint, TimeSpan idleTimeout, SslClientAuthenticationOptions clientAuthenticationOptions, Action`2 streamCapacityCallback, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectHelper.cs:line 135
           at System.Net.Http.HttpConnectionPool.InjectNewHttp3ConnectionAsync(QueueItem queueItem) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectionPool/HttpConnectionPool.Http3.cs:line 274
           at System.Threading.Tasks.TaskCompletionSourceWithCancellation`1.WaitWithCancellationAsync(CancellationToken cancellationToken) in /_/src/libraries/Common/src/System/Threading/Tasks/TaskCompletionSourceWithCancellation.cs:line 21
           at System.Net.Http.HttpConnectionPool.TrySendUsingHttp3Async(HttpRequestMessage request, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectionPool/HttpConnectionPool.Http3.cs:line 96
           at System.Net.Http.HttpConnectionPool.SendWithVersionDetectionAndRetryAsync(HttpRequestMessage request, Boolean async, Boolean doRequestAuth, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/ConnectionPool/HttpConnectionPool.cs:line 419
           at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/RedirectHandler.cs:line 29
           at System.Net.Http.SocketsHttpHandler.<SendAsync>g__CreateHandlerAndSendAsync|115_0(HttpRequestMessage request, CancellationToken cancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/SocketsHttpHandler.cs:line 629
           at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage request, HttpCompletionOption completionOption, CancellationTokenSource cts, Boolean disposeCts, CancellationTokenSource pendingRequestsCts, CancellationToken originalCancellationToken) in /_/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 523
           at Xunit.Assert.RecordExceptionAsync(Func`1 testCode) in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 114

[amanasifkhalid]

Duplicate of #117198

[jkotas]

I am sorry for opening a dup. I searched for "A QUIC protocol error was encountered.", but that have not found the issue you have opened. I usually paste the relevant snippet from the log into the issue to make it clear what's the exact failure the issue is about and make it easier to find.

[amanasifkhalid]

No worries, I'll include a log snippet next time