Bug 34028 - NetworkStream.Close() had better be usable under multithreading async scenario
Summary: NetworkStream.Close() had better be usable under multithreading async scenario
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: unspecified
Hardware: PC Linux
: --- enhancement
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-09-17 01:43 UTC by Atsushi Eno
Modified: 2015-09-17 07:50 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report for Bug 34028 on GitHub or Developer Community if you have new information to add and do not yet see a matching new report.

If the latest results still closely match this report, you can use the original description:

  • Export the original title and description: GitHub Markdown or Developer Community HTML
  • Copy the title and description into the new report. Adjust them to be up-to-date if needed.
  • Add your new information.

In special cases on GitHub you might also want the comments: GitHub Markdown with public comments

Related Links:

Description Atsushi Eno 2015-09-17 01:43:58 UTC
This guy (@melponn at twitter) reported on his some session talk that NetworkStream.Close() causes native crash, when it is used under multithreading circumstance.

(The slides title is in quite nasty words, but skip that, we Japanese don't know English well in general...)

Here is excerpt of repro code, should be called about 100000 times to reproduce the crash.

static async Task TestConnect() {
  try {
    var client = new TcpClient();
    var task = Task.Run( () => client.ConnectAsync("localhost", 8080));
    await task.ConfigureAwait(false);
  } catch (Exception) { 

So far the native crash output is not provided as useful text, only image, at:

Since NetworkStream.Close() is not supported in multithreading use, it should rather be called by design, but there are some general? expectation on such usage [*1], so maybe we'd rather want this to have thread-safe.

[*1] http://stackoverflow.com/questions/12421989/networkstream-readasync-with-a-cancellation-token-never-cancels
Comment 1 INOMATA Kentaro 2015-09-17 07:50:03 UTC
the whole repro code and native stack traces are provided at: