CSHARP-5618: CSOT: Race condition in ExclusiveConnectionPool could lead to ArgumentOutOfRangeException (#1712)

Author: sanych-sun

src/MongoDB.Driver/OperationContext.cs

@@ -17,9 +17,7 @@
 using System.Diagnostics;
 using System.Threading;
 using System.Threading.Tasks;
-#if !NET6_0_OR_GREATER
 using MongoDB.Driver.Core.Misc;
-#endif
 
 namespace MongoDB.Driver
 {
@@ -36,7 +34,7 @@ public OperationContext(TimeSpan timeout, CancellationToken cancellationToken)
  internal OperationContext(Stopwatch stopwatch, TimeSpan timeout, CancellationToken cancellationToken)
  {
  Stopwatch = stopwatch;
- Timeout = timeout;
+ Timeout = Ensure.IsInfiniteOrGreaterThanOrEqualToZero(timeout, nameof(timeout));
  CancellationToken = cancellationToken;
  }
 
@@ -53,7 +51,13 @@ public TimeSpan RemainingTimeout
  return System.Threading.Timeout.InfiniteTimeSpan;
  }
 
- return Timeout - Stopwatch.Elapsed;
+ var result = Timeout - Stopwatch.Elapsed;
+ if (result < TimeSpan.Zero)
+ {
+ result = TimeSpan.Zero;
+ }
+
+ return result;
  }
  }
 
@@ -69,7 +73,7 @@ public bool IsTimedOut()
  return false;
  }
 
- return remainingTimeout < TimeSpan.Zero;
+ return remainingTimeout == TimeSpan.Zero;
  }
 
  public void ThrowIfTimedOutOrCanceled()
@@ -141,6 +145,8 @@ public async Task WaitTaskAsync(Task task)
 
  public OperationContext WithTimeout(TimeSpan timeout)
  {
+ Ensure.IsInfiniteOrGreaterThanOrEqualToZero(timeout, nameof(timeout));
+
  var remainingTimeout = RemainingTimeout;
  if (timeout == System.Threading.Timeout.InfiniteTimeSpan)
  {

tests/MongoDB.Bson.TestHelpers/Threading/ThreadingUtilities.cs

@@ -29,7 +29,7 @@ public static void ExecuteOnNewThreads(int threadsCount, Action<int> action, int
 
  if (exceptions.Any())
  {
- throw exceptions.First();
+ throw new AggregateException(exceptions);
  }
  }
 

tests/MongoDB.Driver.Tests/OperationContextTests.cs

@@ -42,6 +42,14 @@ public void Constructor_should_initialize_properties()
  operationContext.ParentContext.Should().BeNull();
  }
 
+ [Fact]
+ public void Constructor_throws_on_negative_timeout()
+ {
+ var exception = Record.Exception(() => new OperationContext(TimeSpan.FromSeconds(-5), CancellationToken.None));
+
+ exception.Should().BeOfType<ArgumentOutOfRangeException>();
+ }
+
  [Fact]
  public void RemainingTimeout_should_calculate()
  {
@@ -68,16 +76,12 @@ public void RemainingTimeout_should_return_infinite_for_infinite_timeout()
  }
 
  [Fact]
- public void RemainingTimeout_could_be_negative()
+ public void RemainingTimeout_should_return_zero_for_timeout_context()
  {
- var timeout = TimeSpan.FromMilliseconds(5);
- var stopwatch = Stopwatch.StartNew();
+ var operationContext = new OperationContext(TimeSpan.FromMilliseconds(5), CancellationToken.None);
  Thread.Sleep(10);
- stopwatch.Stop();
 
- var operationContext = new OperationContext(stopwatch, timeout, CancellationToken.None);
-
- operationContext.RemainingTimeout.Should().Be(timeout - stopwatch.Elapsed);
+ operationContext.RemainingTimeout.Should().Be(TimeSpan.Zero);
  }
 
  [Theory]
@@ -276,6 +280,29 @@ public void WithTimeout_should_set_ParentContext()
 
  resultContext.ParentContext.Should().Be(operationContext);
  }
+
+ [Fact]
+ public void WithTimeout_should_create_timed_out_context_on_timed_out_context()
+ {
+ var operationContext = new OperationContext(TimeSpan.FromMilliseconds(5), CancellationToken.None);
+ Thread.Sleep(10);
+ operationContext.IsTimedOut().Should().BeTrue();
+
+ var resultContext = operationContext.WithTimeout(TimeSpan.FromSeconds(10));
+
+ resultContext.IsTimedOut().Should().BeTrue();
+ }
+
+ [Fact]
+ public void WithTimeout_throws_on_negative_timeout()
+ {
+ var operationContext = new OperationContext(Timeout.InfiniteTimeSpan, CancellationToken.None);
+
+ var exception = Record.Exception(() => operationContext.WithTimeout(TimeSpan.FromSeconds(-5)));
+
+ exception.Should().BeOfType<ArgumentOutOfRangeException>()
+ .Subject.ParamName.Should().Be("timeout");
+ }
  }
 }