Fix empty byte[] bug in EventSource

src/libraries/System.Diagnostics.Tracing/tests/BasicEventSourceTest/TestsWriteEventToListener.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Xunit;
@@ -18,7 +19,7 @@ public partial class TestsWriteEventToListener
     {
         [Fact]
         [ActiveIssue("https://github.com/dotnet/runtime/issues/21569", TargetFrameworkMonikers.NetFramework)]
-        public void Test_WriteEvent_ArgsBasicTypes()
+        public unsafe void Test_WriteEvent_ArgsBasicTypes()
         {
             TestUtilities.CheckNoEventSourcesRunning("Start");
 
@@ -104,11 +105,42 @@ public void Test_WriteEvent_ArgsBasicTypes()
 
                     #region Validate byte array arguments
 
+                    var rng = new Random(42);
+
                     byte[] arr = new byte[20];
+                    rng.NextBytes(arr);
                     log.EventWithByteArray(arr);
                     Assert.Equal(52, LoudListener.t_lastEvent.EventId);
                     Assert.Equal(1, LoudListener.t_lastEvent.Payload.Count);
-                    Assert.Equal(arr.Length, ((byte[])LoudListener.t_lastEvent.Payload[0]).Length);
+                    Assert.Equal(arr, (byte[])LoudListener.t_lastEvent.Payload[0]);
+
+                    arr = new byte[20];
+                    rng.NextBytes(arr);
+                    log.EventWithByteArrayCustom(arr);
+                    Assert.Equal(53, LoudListener.t_lastEvent.EventId);
+                    Assert.Equal(1, LoudListener.t_lastEvent.Payload.Count);
+                    Assert.Equal(arr, (byte[])LoudListener.t_lastEvent.Payload[0]);
+
+                    arr = new byte[0];
+                    log.EventWithByteArrayCustom(arr);
+                    Assert.Equal(53, LoudListener.t_lastEvent.EventId);
+                    Assert.Equal(1, LoudListener.t_lastEvent.Payload.Count);
+                    Assert.Equal(arr, (byte[])LoudListener.t_lastEvent.Payload[0]);
+
+                    arr = new byte[20];
+                    rng.NextBytes(arr);
+                    fixed (byte* arrPtr = arr)
+                    {
+                        log.EventWithBytePointer(arrPtr, arr.Length);
+                    }
+                    Assert.Equal(54, LoudListener.t_lastEvent.EventId);
+                    Assert.Equal(1, LoudListener.t_lastEvent.Payload.Count);
+                    Assert.Equal(arr, (byte[])LoudListener.t_lastEvent.Payload[0]);
+
+                    log.EventWithBytePointer((byte*)IntPtr.Zero, 0);
+                    Assert.Equal(54, LoudListener.t_lastEvent.EventId);
+                    Assert.Equal(1, LoudListener.t_lastEvent.Payload.Count);
+                    Assert.Equal(Array.Empty<byte>(), (byte[])LoudListener.t_lastEvent.Payload[0]);
 
                     #endregion
 

src/libraries/System.Diagnostics.Tracing/tests/CustomEventSources/EventSourceTest.cs

@@ -326,6 +326,46 @@ public void EventWithByteArray(byte[] arr)
             this.WriteEvent(52, arr);
         }
 
+        [Event(53)]
+        public unsafe void EventWithByteArrayCustom(byte[] arr)
+        {
+            // This implementation does not guard against passing null as DataPointer for Length == 0 case
+            arr ??= Array.Empty<byte>();
+
+            fixed (byte* arg1Ptr = arr)
+            {
+                int bufferLength = arr.Length;
+
+                const int NumEventDatas = 2;
+                var descrs = stackalloc EventData[NumEventDatas];
+
+                descrs[0] = new EventData
+                {
+                    DataPointer = (IntPtr)(&bufferLength),
+                    Size = sizeof(int)
+                };
+                descrs[1] = new EventData
+                {
+                    DataPointer = (IntPtr)arg1Ptr,
+                    Size = arr.Length
+                };
+
+                WriteEventCore(53, 2, descrs);
+            }
+        }
+
+        [Event(54)]
+        public unsafe void EventWithBytePointer(byte* ptr, int length)
+        {
+            var data = new EventData
+            {
+                DataPointer = (IntPtr)ptr,
+                Size = length
+            };
+
+            WriteEventCore(54, 1, &data);
+        }
+
         #region Keywords / Tasks /Opcodes / Channels
         public class Keywords
         {

src/libraries/System.Net.Sockets/tests/FunctionalTests/LoggingTest.cs

@@ -2,7 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections.Concurrent;
-using System.Diagnostics;
 using System.Diagnostics.Tracing;
 using Microsoft.DotNet.RemoteExecutor;
 using Xunit;
@@ -34,32 +33,31 @@ public static void EventSource_ExistsWithCorrectId()
 
         [OuterLoop]
         [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]
-        [ActiveIssue("https://github.com/dotnet/runtime/issues/50639")]
         public void EventSource_EventsRaisedAsExpected()
         {
-            RemoteExecutor.Invoke(() =>
+            RemoteExecutor.Invoke(async () =>
             {
                 using (var listener = new TestEventListener("Private.InternalDiagnostics.System.Net.Sockets", EventLevel.Verbose))
                 {
                     var events = new ConcurrentQueue<EventWrittenEventArgs>();
-                    listener.RunWithCallback(events.Enqueue, () =>
+                    await listener.RunWithCallbackAsync(events.Enqueue, async () =>
                     {
                         // Invoke several tests to execute code paths while tracing is enabled
 
-                        new SendReceive_Sync(null).SendRecv_Stream_TCP(IPAddress.Loopback, false).GetAwaiter();
-                        new SendReceive_Sync(null).SendRecv_Stream_TCP(IPAddress.Loopback, true).GetAwaiter();
+                        await new SendReceive_Sync(null).SendRecv_Stream_TCP(IPAddress.Loopback, false);
+                        await new SendReceive_Sync(null).SendRecv_Stream_TCP(IPAddress.Loopback, true);
 
-                        new SendReceive_Task(null).SendRecv_Stream_TCP(IPAddress.Loopback, false).GetAwaiter();
-                        new SendReceive_Task(null).SendRecv_Stream_TCP(IPAddress.Loopback, true).GetAwaiter();
+                        await new SendReceive_Task(null).SendRecv_Stream_TCP(IPAddress.Loopback, false);
+                        await new SendReceive_Task(null).SendRecv_Stream_TCP(IPAddress.Loopback, true);
 
-                        new SendReceive_Eap(null).SendRecv_Stream_TCP(IPAddress.Loopback, false).GetAwaiter();
-                        new SendReceive_Eap(null).SendRecv_Stream_TCP(IPAddress.Loopback, true).GetAwaiter();
+                        await new SendReceive_Eap(null).SendRecv_Stream_TCP(IPAddress.Loopback, false);
+                        await new SendReceive_Eap(null).SendRecv_Stream_TCP(IPAddress.Loopback, true);
 
-                        new SendReceive_Apm(null).SendRecv_Stream_TCP(IPAddress.Loopback, false).GetAwaiter();
-                        new SendReceive_Apm(null).SendRecv_Stream_TCP(IPAddress.Loopback, true).GetAwaiter();
+                        await new SendReceive_Apm(null).SendRecv_Stream_TCP(IPAddress.Loopback, false);
+                        await new SendReceive_Apm(null).SendRecv_Stream_TCP(IPAddress.Loopback, true);
 
-                        new NetworkStreamTest().CopyToAsync_AllDataCopied(4096, true).GetAwaiter().GetResult();
-                        new NetworkStreamTest().Timeout_Roundtrips().GetAwaiter().GetResult();
+                        await new NetworkStreamTest().CopyToAsync_AllDataCopied(4096, true);
+                        await new NetworkStreamTest().Timeout_Roundtrips();
                     });
                     Assert.DoesNotContain(events, ev => ev.EventId == 0); // errors from the EventSource itself
                     Assert.InRange(events.Count, 1, int.MaxValue);

src/libraries/System.Private.CoreLib/src/System/Diagnostics/Tracing/EventSource.cs

@@ -1840,7 +1840,10 @@ private static unsafe void DecodeObjects(object?[] decodedObjects, ParameterInfo
 
             BytePtr:
                 var blob = new byte[data->Size];
-                Marshal.Copy(dataPointer, blob, 0, blob.Length);
+                if (blob.Length != 0)
+                {
+                    Marshal.Copy(dataPointer, blob, 0, blob.Length);
+                }
                 decoded = blob;
                 goto Store;