| Bug #101507 | MySqlCommand.Cancel throws NullReferenceException for a Closed connection | ||
|---|---|---|---|
| Submitted: | 8 Nov 2020 2:06 | Modified: | 12 Oct 2022 22:09 |
| Reporter: | Bradley Grainger (OCA) | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | Connector / NET | Severity: | S3 (Non-critical) |
| Version: | 8.0.22 | OS: | Windows (10) |
| Assigned to: | CPU Architecture: | Any | |
[8 Nov 2020 4:35]
MySQL Verification Team
Hello Bradley, Thank you for the report and test case. Verified as described. regards, Umesh
[22 Sep 2022 20:25]
Omar Chavez
Posted by developer: Verified using Connector/Net version 8.0.30
[7 Oct 2022 16:30]
Daniel Valdez
Posted by developer: A verification was added in the MySqlCommand.Cancel() method that checks the connection state.
[12 Oct 2022 22:09]
Christine Cole
Posted by developer: Fixed as of the upcoming MySQL Connector/NET 8.0.32 release, and here's the proposed changelog entry from the documentation team: An unexpected System.NullReferenceException message was returned when the MySqlCommand.Cancel() method was called for a command associated with a closed (or disposed) MySqlConnection object. The issue is resolved with new validation in the method that now checks the connection state. Thank you for the bug report.
Description: When MySqlCommand.Cancel is called for a command associated with a closed (or disposed) MySqlConnection, it throws a NullReferenceException. I would expect it to silently succeed. If an exception must be thrown, ObjectDisposedException or InvalidOperationException would be more appropriate than NullReferenceException. System.NullReferenceException at MySql.Data.MySqlClient.MySqlConnection.get_ServerThread() at MySql.Data.MySqlClient.MySqlConnection.CancelQuery(Int32 timeout) at MySql.Data.MySqlClient.MySqlCommand.Cancel() How to repeat: var connection = new MySqlConnection("..."); var command = connection.CreateCommand(); command.Cancel(); // *** OR *** var connection = new MySqlConnection(csb.ConnectionString); connection.Open(); var command = connection.CreateCommand(); connection.Close(); command.Cancel();