NullReferenceException in MySqlConnector.Utilities.TimerQueue.Callback

[csandr]

Software versions
MySqlConnector version: 2.1.9
CoreCLR Version: 6.0.522.21309
.NET Version: 6.0.5

Description: The process was terminated due to an unhandled exception.
Exception Info: System.NullReferenceException: Object reference not set to an instance of an object.
   at MySqlConnector.MySqlConnection.Cancel(ICancellableCommand command, Int32 commandId, Boolean isCancel) in /_/src/MySqlConnector/MySqlConnection.cs:line 780
   at MySqlConnector.MySqlCommand.CancelCommandForTimeout() in /_/src/MySqlConnector/MySqlCommand.cs:line 424
   at MySqlConnector.Utilities.TimerQueue.Callback(Object obj) in /_/src/MySqlConnector/Utilities/TimerQueue.cs:line 92
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
   at System.Threading.TimerQueueTimer.Fire(Boolean isThreadPool)
   at System.Threading.TimerQueue.FireNextTimers()

Link to the exception line

Last second logs

MySqlConnector.CommandExecutor:

04:06:00.2176 Trace Session1.225 ExecuteReader Synchronous CommandCount: 1 
04:06:01.3484 Trace Session1.225 ExecuteReader Synchronous CommandCount: 1 
04:06:02.5396 Trace Session1.225 ExecuteReader Synchronous CommandCount: 1 
04:06:02.6449 Trace Session1.226 ExecuteReader Synchronous CommandCount: 1 
04:06:02.9968 Trace Session1.225 ExecuteReader Synchronous CommandCount: 1 
04:06:03.1121 Trace Session1.226 ExecuteReader Synchronous CommandCount: 1 

MySqlConnector.ConnectionPool

04:06:00.1477 Trace Pool1 receiving Session1.226 back 
04:06:00.2176 Trace Pool1 returning pooled Session1.225 to caller; LeasedSessionsCount=2 
04:06:00.4365 Trace Pool1 receiving Session1.225 back 
04:06:01.1205 Trace Pool1 waiting for an available session 
04:06:01.1205 Trace Pool1 found an existing session; checking it for validity 
04:06:01.3484 Trace Pool1 returning pooled Session1.225 to caller; LeasedSessionsCount=2 
04:06:01.5743 Trace Pool1 receiving Session1.225 back 
04:06:02.3118 Trace Pool1 waiting for an available session 
04:06:02.3118 Trace Pool1 found an existing session; checking it for validity 
04:06:02.4194 Trace Pool1 waiting for an available session 
04:06:02.4194 Trace Pool1 found an existing session; checking it for validity 
04:06:02.5107 Trace Pool1 receiving Session1.224 back 
04:06:02.5107 Info Pool1 received invalid Session1.224; destroying it 
04:06:02.5396 Trace Pool1 returning pooled Session1.225 to caller; LeasedSessionsCount=1 
04:06:02.6449 Trace Pool1 returning pooled Session1.226 to caller; LeasedSessionsCount=2 
04:06:02.7658 Trace Pool1 receiving Session1.225 back 
04:06:02.7658 Trace Pool1 waiting for an available session 
04:06:02.7658 Trace Pool1 found an existing session; checking it for validity 
04:06:02.8706 Trace Pool1 receiving Session1.226 back 
04:06:02.8706 Trace Pool1 waiting for an available session 
04:06:02.8706 Trace Pool1 found an existing session; checking it for validity 
04:06:02.9968 Trace Pool1 returning pooled Session1.225 to caller; LeasedSessionsCount=1 
04:06:03.1121 Trace Pool1 returning pooled Session1.226 to caller; LeasedSessionsCount=2 
04:06:10.1245 Trace Pool1 receiving Session1.226 back 
04:06:10.1245 Trace Pool1 receiving Session1.225 back 
04:06:10.1245 Trace Pool1 waiting for an available session 
04:06:10.1245 Trace Pool1 found an existing session; checking it for validity 

MySqlConnector.MySqlConnection

04:06:01.4547 Debug CommandId 24104 for Session1.224 has been canceled via command timeout. 
04:06:01.4547 Debug Created new non-pooled Session0.

MySqlConnector.ServerSession
https://pastebin.com/KVqPzCPb

[Graf2233]

MySqlConnector version: 2.1.10
CoreCLR Version: 6.0.522.21309
.NET Version: 6.0.5

Description: The process was terminated due to an unhandled exception.
Exception Info: System.NullReferenceException: Object reference not set to an instance of an object.
at MySqlConnector.MySqlConnection.Cancel(ICancellableCommand command, Int32 commandId, Boolean isCancel) in //src/MySqlConnector/MySqlConnection.cs:line 780
at MySqlConnector.MySqlCommand.CancelCommandForTimeout() in //src/MySqlConnector/MySqlCommand.cs:line 424
at MySqlConnector.Utilities.TimerQueue.Callback(Object obj) in /_/src/MySqlConnector/Utilities/TimerQueue.cs:line 92
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at System.Threading.TimerQueueTimer.Fire(Boolean isThreadPool)
at System.Threading.TimerQueue.FireNextTimers()

[bgrainger]

Fixed in 2.1.11.