Fix WaitForConnectionAsync when NamedPipeServerStream is disposed

src/libraries/System.IO.Pipes/src/System/IO/Pipes/NamedPipeServerStream.Unix.cs

@@ -20,6 +20,7 @@ public sealed partial class NamedPipeServerStream : PipeStream
         private int _inBufferSize;
         private int _outBufferSize;
         private HandleInheritability _inheritability;
+        private CancellationTokenSource _internalTokenSource = new CancellationTokenSource();
 
         private void Create(string pipeName, PipeDirection direction, int maxNumberOfServerInstances,
                 PipeTransmissionMode transmissionMode, PipeOptions options, int inBufferSize, int outBufferSize,
@@ -77,8 +78,25 @@ public Task WaitForConnectionAsync(CancellationToken cancellationToken)
                 Task.FromCanceled(cancellationToken) :
                 WaitForConnectionAsyncCore();
 
-            async Task WaitForConnectionAsyncCore() =>
-               HandleAcceptedSocket(await _instance!.ListeningSocket.AcceptAsync(cancellationToken).ConfigureAwait(false));
+            async Task WaitForConnectionAsyncCore()
+            {
+                Socket acceptedSocket;
+                CancellationTokenSource linkedTokenSource = CancellationTokenSource.CreateLinkedTokenSource(_internalTokenSource.Token, cancellationToken);
+                try
+                {
+                    acceptedSocket = await _instance!.ListeningSocket.AcceptAsync(linkedTokenSource.Token).ConfigureAwait(false);
+                }
+                catch (OperationCanceledException) when (!cancellationToken.IsCancellationRequested)
+                {
+                    throw new IOException(SR.IO_PipeBroken);
+                }
+                finally
+                {
+                    linkedTokenSource.Dispose();
+                }
+
+                HandleAcceptedSocket(acceptedSocket);
+            }
         }
 
         private void HandleAcceptedSocket(Socket acceptedSocket)
@@ -116,9 +134,19 @@ private void HandleAcceptedSocket(Socket acceptedSocket)
             State = PipeState.Connected;
         }
 
-        internal override void DisposeCore(bool disposing) =>
+        internal override void DisposeCore(bool disposing)
+        {
             Interlocked.Exchange(ref _instance, null)?.Dispose(disposing); // interlocked to avoid shared state problems from erroneous double/concurrent disposes
 
+            if (disposing)
+            {
+                if (State != PipeState.Closed)
+                {
+                    _internalTokenSource.Cancel();
+                }
+            }
+        }
+
         public void Disconnect()
         {
             CheckDisconnectOperations();

src/libraries/System.IO.Pipes/tests/PipeStreamConformanceTests.cs

@@ -63,7 +63,16 @@ public abstract class NamedPipeStreamConformanceTests : PipeStreamConformanceTes
     {
         protected override bool BrokenPipePropagatedImmediately => OperatingSystem.IsWindows(); // On Unix, implemented on Sockets, where it won't propagate immediate
 
-        protected abstract (NamedPipeServerStream Server, NamedPipeClientStream Client) CreateServerAndClientStreams();
+        protected abstract NamedPipeServerStream CreateServerStream(string pipeName, int maxInstances = 1);
+        protected abstract NamedPipeClientStream CreateClientStream(string pipeName);
+
+        protected (NamedPipeServerStream Server, NamedPipeClientStream Client) CreateServerAndClientStreams()
+        {
+            string pipeName = GetUniquePipeName();
+            NamedPipeServerStream server = CreateServerStream(pipeName);
+            NamedPipeClientStream client = CreateClientStream(pipeName);
+            return (server, client);
+        }
 
         protected sealed override async Task<StreamPair> CreateConnectedStreamsAsync()
         {
@@ -88,6 +97,15 @@ protected sealed override async Task<StreamPair> CreateConnectedStreamsAsync()
             return ((NamedPipeServerStream)streams.Stream2, (NamedPipeClientStream)streams.Stream1);
         }
 
+        protected async Task ValidateDisposedExceptionsAsync(NamedPipeServerStream server)
+        {
+            Assert.Throws<ObjectDisposedException>(() => server.Disconnect());
+            Assert.Throws<ObjectDisposedException>(() => server.GetImpersonationUserName());
+            Assert.Throws<ObjectDisposedException>(() => server.WaitForConnection());
+            await Assert.ThrowsAsync<ObjectDisposedException>(() => server.WaitForConnectionAsync());
+            await ValidateDisposedExceptionsAsync(server as Stream);
+        }
+
         /// <summary>
         /// Yields every combination of testing options for the OneWayReadWrites test
         /// </summary>
@@ -629,6 +647,37 @@ public async Task CancelTokenOn_Client_ReadWriteCancelledToken_Throws_OperationC
                 await Assert.ThrowsAnyAsync<OperationCanceledException>(() => clientWriteToken);
             }
         }
+
+        [Fact]
+        public async Task TwoServerInstances_OnceDisposed_Throws()
+        {
+            string pipeName = GetUniquePipeName();
+            NamedPipeServerStream server1 = CreateServerStream(pipeName, 2);
+            using NamedPipeServerStream server2 = CreateServerStream(pipeName, 2);
+
+            Task wait1 = server1.WaitForConnectionAsync();
+            Task wait2 = server2.WaitForConnectionAsync();
+            server1.Dispose();
+            await ValidateDisposedExceptionsAsync(server1);
+
+            using NamedPipeClientStream client = CreateClientStream(pipeName);
+            await client.ConnectAsync();
+
+            await Assert.ThrowsAsync<IOException>(() => wait1);
+
+            await wait2;
+
+            foreach ((Stream writeable, Stream readable) in GetReadWritePairs((server2, client)))
+            {
+                byte[] sent = new byte[] { 123 };
+                byte[] received = new byte[] { 0 };
+
+                Task t = Task.Run(() => writeable.Write(sent, 0, sent.Length));
+                Assert.Equal(sent.Length, readable.Read(received, 0, sent.Length));
+                Assert.Equal(sent, received);
+                await t;
+            }
+        }
     }
 
     public sealed class AnonymousPipeTest_ServerIn_ClientOut : AnonymousPipeStreamConformanceTests
@@ -653,34 +702,28 @@ protected override (AnonymousPipeServerStream Server, AnonymousPipeClientStream
 
     public sealed class NamedPipeTest_ServerOut_ClientIn : NamedPipeStreamConformanceTests
     {
-        protected override (NamedPipeServerStream Server, NamedPipeClientStream Client) CreateServerAndClientStreams()
-        {
-            string pipeName = PipeStreamConformanceTests.GetUniquePipeName();
-            var server = new NamedPipeServerStream(pipeName, PipeDirection.Out, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
-            var client = new NamedPipeClientStream(".", pipeName, PipeDirection.In, PipeOptions.Asynchronous);
-            return (server, client);
-        }
+        protected override NamedPipeServerStream CreateServerStream(string pipeName, int maxInstances = 1) =>
+            new NamedPipeServerStream(pipeName, PipeDirection.Out, maxInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
+
+        protected override NamedPipeClientStream CreateClientStream(string pipeName) =>
+            new NamedPipeClientStream(".", pipeName, PipeDirection.In, PipeOptions.Asynchronous);
     }
 
     public sealed class NamedPipeTest_ServerIn_ClientOut : NamedPipeStreamConformanceTests
     {
-        protected override (NamedPipeServerStream Server, NamedPipeClientStream Client) CreateServerAndClientStreams()
-        {
-            string pipeName = PipeStreamConformanceTests.GetUniquePipeName();
-            var server = new NamedPipeServerStream(pipeName, PipeDirection.In, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
-            var client = new NamedPipeClientStream(".", pipeName, PipeDirection.Out, PipeOptions.Asynchronous);
-            return (server, client);
-        }
+        protected override NamedPipeServerStream CreateServerStream(string pipeName, int maxInstances = 1) =>
+            new NamedPipeServerStream(pipeName, PipeDirection.In, maxInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
+
+        protected override NamedPipeClientStream CreateClientStream(string pipeName) =>
+            new NamedPipeClientStream(".", pipeName, PipeDirection.Out, PipeOptions.Asynchronous);
     }
 
     public sealed class NamedPipeTest_ServerInOut_ClientInOut : NamedPipeStreamConformanceTests
     {
-        protected override (NamedPipeServerStream Server, NamedPipeClientStream Client) CreateServerAndClientStreams()
-        {
-            string pipeName = PipeStreamConformanceTests.GetUniquePipeName();
-            var server = new NamedPipeServerStream(pipeName, PipeDirection.InOut, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
-            var client = new NamedPipeClientStream(".", pipeName, PipeDirection.InOut, PipeOptions.Asynchronous);
-            return (server, client);
-        }
+        protected override NamedPipeServerStream CreateServerStream(string pipeName, int maxInstances = 1) =>
+            new NamedPipeServerStream(pipeName, PipeDirection.InOut, maxInstances, PipeTransmissionMode.Byte, PipeOptions.Asynchronous);
+
+        protected override NamedPipeClientStream CreateClientStream(string pipeName) =>
+            new NamedPipeClientStream(".", pipeName, PipeDirection.InOut, PipeOptions.Asynchronous);
     }
 }