[release/7.0-rc1] Fix leak caused by not disposing the scoped parent …

…service provider (#74362)

* Fix leaks caused by not disposing the parent scoped ServiceProvider

* Address the feedback

Co-authored-by: Tarek Mahmoud Sayed <tarekms@microsoft.com>

src/libraries/Microsoft.Extensions.DependencyInjection/src/ServiceLookup/ServiceProviderEngineScope.cs

@@ -187,12 +187,20 @@ static async ValueTask Await(int i, ValueTask vt, List<object> toDispose)
  // No further changes to _state.Disposables, are allowed.
  _disposed = true;
 
- // ResolvedServices is never cleared for singletons because there might be a compilation running in background
- // trying to get a cached singleton service. If it doesn't find it
- // it will try to create a new one which will result in an ObjectDisposedException.
+ }
 
- return _disposables;
+ if (IsRootScope && !RootProvider.IsDisposed())
+ {
+ // If this ServiceProviderEngineScope instance is a root scope, disposing this instance will need to dispose the RootProvider too.
+ // Otherwise the RootProvider will never get disposed and will leak.
+ // Note, if the RootProvider get disposed first, it will automatically dispose all attached ServiceProviderEngineScope objects.
+ RootProvider.Dispose();
  }
+
+ // ResolvedServices is never cleared for singletons because there might be a compilation running in background
+ // trying to get a cached singleton service. If it doesn't find it
+ // it will try to create a new one which will result in an ObjectDisposedException.
+ return _disposables;
  }
  }
 }

src/libraries/Microsoft.Extensions.DependencyInjection/src/ServiceProvider.cs

@@ -89,6 +89,8 @@ internal ServiceProvider(ICollection<ServiceDescriptor> serviceDescriptors, Serv
  /// <returns>The service that was produced.</returns>
  public object? GetService(Type serviceType) => GetService(serviceType, Root);
 
+ internal bool IsDisposed() => _disposed;
+
  /// <inheritdoc />
  public void Dispose()
  {

src/libraries/Microsoft.Extensions.DependencyInjection/tests/DI.Tests/ServiceProviderEngineScopeTests.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 Microsoft.Extensions.DependencyInjection.Specification.Fakes;
 using Xunit;
 
@@ -17,5 +18,16 @@ public void DoubleDisposeWorks()
  serviceProviderEngineScope.Dispose();
  serviceProviderEngineScope.Dispose();
  }
+
+ [Fact]
+ public void RootEngineScopeDisposeTest()
+ {
+ var services = new ServiceCollection();
+ ServiceProvider sp = services.BuildServiceProvider();
+ var s = sp.GetRequiredService<IServiceProvider>();
+ ((IDisposable)s).Dispose();
+
+ Assert.Throws<ObjectDisposedException>(() => sp.GetRequiredService<IServiceProvider>());
+ }
  }
 }