Dispose ServerSession on failure. Fixes #1248

Author: bgrainger

src/MySqlConnector/Core/ConnectionPool.cs

@@ -383,9 +383,18 @@ private async ValueTask<ServerSession> ConnectSessionAsync(MySqlConnection conne
 		var session = new ServerSession(this, m_generation, Interlocked.Increment(ref m_lastSessionId));
 		if (Log.IsDebugEnabled())
 			Log.Debug(logMessage, m_logArguments[0], session.Id);
-		var statusInfo = await session.ConnectAsync(ConnectionSettings, connection, startTickCount, m_loadBalancer, activity, ioBehavior, cancellationToken).ConfigureAwait(false);
-		Exception? redirectionException = null;
+		string? statusInfo;
+		try
+		{
+			statusInfo = await session.ConnectAsync(ConnectionSettings, connection, startTickCount, m_loadBalancer, activity, ioBehavior, cancellationToken).ConfigureAwait(false);
+		}
+		catch (Exception)
+		{
+			await session.DisposeAsync(ioBehavior, default).ConfigureAwait(false);
+			throw;
+		}
 
+		Exception? redirectionException = null;
 		if (statusInfo is not null && statusInfo.StartsWith("Location: mysql://", StringComparison.Ordinal))
 		{
 			// server redirection string has the format "Location: mysql://{host}:{port}/user={userId}[&ttl={ttl}]"

src/MySqlConnector/MySqlConnection.cs

@@ -931,8 +931,16 @@ private async ValueTask<ServerSession> CreateSessionAsync(ConnectionPool? pool,
 				var session = new ServerSession();
 				session.OwningConnection = new WeakReference<MySqlConnection>(this);
 				Log.Debug("Created new non-pooled Session{0}", session.Id);
-				await session.ConnectAsync(connectionSettings, this, startTickCount, loadBalancer, activity, actualIOBehavior, connectToken).ConfigureAwait(false);
-				return session;
+				try
+				{
+					await session.ConnectAsync(connectionSettings, this, startTickCount, loadBalancer, activity, actualIOBehavior, connectToken).ConfigureAwait(false);
+					return session;
+				}
+				catch (Exception)
+				{
+					await session.DisposeAsync(actualIOBehavior, default).ConfigureAwait(false);
+					throw;
+				}
 			}
 		}
 		catch (OperationCanceledException) when (timeoutSource?.IsCancellationRequested is true)