Bug 58671 - SSL hang read from AD
Summary: SSL hang read from AD
Status: NEW
Alias: None
Product: Runtime
Classification: Mono
Component: GC ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-08-09 15:05 UTC by Mehmet Eliyesil
Modified: 2017-11-20 22:36 UTC (History)
4 users (show)

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

ZIP containing text file of console output (2.10 MB, application/x-zip-compressed)
2017-08-09 15:05 UTC, Mehmet Eliyesil

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Description Mehmet Eliyesil 2017-08-09 15:05:22 UTC
Created attachment 24103 [details]
ZIP containing text file of console output

We are using Novell.Ldap library to connect to ActiveDirectory using SSL, running on CentOS-7. With mono version, there were no issues, with mono version we are seeing consistent hang at a customer site, while reading large amount of data from AD server.  Running the same binaries on both mono versions, 3.8 works where as 4.8 hangs.

Unfortunately, we can not reproduce the hang in house, this is happening at customer sites only.
In house reading schema is trying to read 200K bytes and it gets chunked at 16k, at customer site trying to read 400K bytes and it gets chunked at 7K. ChiperSuite was Rijandael 256 in both cases.

Attached ZIP file contains the console output from mono --trace:Mono.Security 

see line: <<< NOTE: Hang occurs here in log file where the hang occurs.
Comment 1 Marek Safar 2017-09-08 23:50:41 UTC
Thank you for your report!

Iā€™m unable to reproduce this issue locally using the information you provided. In order to investigate the issue further can you please attach a reproduction project and steps to reproduce this issue? For help on writing a bug report, please see our guide on this topic:


Some of your next steps would be:

1. Including a sample project or steps to reproduce this problem
2. Your Version Information
3. Your expected results and actual results

Thank you!
Comment 2 Mehmet Eliyesil 2017-11-16 20:29:31 UTC
This turned out to be mono sgen GC problem. Running a simple sample program with MONO_GC_PARAMS=nursery-size=16m fixes the issue at the customer site.
Comment 3 Marek Safar 2017-11-20 22:36:55 UTC
Setting to NEW