Bug 290424

Summary:	Lock screen/screen saver hangs when home directory mounted over Kerberized NFS expires
Product:	[Unmaintained] plasma4	Reporter:	Arnout Boelens <a.m.p.boelens>
Component:	screensaver overlay	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED UNMAINTAINED
Severity:	major	CC:	allistar.m, chanika, stasnel
Priority:	NOR
Version First Reported In:	4.9-git
Target Milestone:	---
Platform:	Debian unstable
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Arnout Boelens 2012-01-02 18:50:17 UTC

Version:           unspecified (using KDE 4.6.5) 
OS:                Linux

I run a LDAP+NFS+Kerberos setup where user directories are mounted over Kerberized NFS directories. When upgrading one of the workstations to Debian unstable, I realized that the screen saver/lock screen in KDE 4 needs data from the users home directories. This means that when a NFS ticket expires while the screen is locked, it is not possible to renew the Kerberos ticket by typing in the password to unlock the screen, and the system hangs. I found this link describing the problem:

http://www.spinics.net/lists/linux-nfs/msg25505.html

and in there it is also suggested that the GNOME screen savers are adjusted to keep working when a users home directory expires. Could this be implemented for KDE too?

Reproducible: Always

Steps to Reproduce:
* Mount home directory over Kerberized NFS
* Wait for ticket to expire

Actual Results:  
(un)lock screen hangs

Expected Results:  
I can type in my password in the unlock screen dialog, my NFS ticket gets renewed, and I can continue working on my computer.

OS: Linux (x86_64) release 3.1.0-1-amd64
Compiler: gcc

Comment 1 Myriam Schweingruber 2012-05-28 13:16:35 UTC

Is this still valid with KDE 4.8.3 or trunk?

Comment 2 Arnout Boelens 2012-05-29 15:10:40 UTC

I am afraid I will not be able to test this. I graduated in the meanwhile and do not have access to this computer anymore.

Comment 3 Myriam Schweingruber 2012-05-29 22:35:55 UTC

Thank you for the fast feedback.

Comment 4 Oswald Buddenhagen 2012-05-30 06:49:25 UTC

the problem seems perfectly plausible and i haven't seen any activity to actually fix it, so the ticket should stay open.

reproducing the setup with a local mount is actually quite easy, but somewhat time consuming.

the fix would be avoiding that the unlocker accesses the home directory, which is "quite challenging" given the complexity of the kde library stack.
see also https://bugs.kde.org/show_bug.cgi?id=272870 for a more serious incarnation of the problem.

Comment 5 Nate Graham 2018-06-08 18:21:20 UTC

Hello!

This bug report was filed for KDE Plasma 4, which reached end-of-support status in August 2015. KDE Plasma 5's desktop shell has been almost completely rewritten for better performance and usability, so it is likely that this bug has already been resolved in Plasma 5.

Accordingly, we hope you understand why we must close this bug report. If the issue described  here is still present in KDE Plasma 5.12 or later, please feel free to open a new ticket in the "plasmashell" product after reading https://community.kde.org/Get_Involved/Bug_Reporting

If you would like to get involved in KDE's bug triaging effort so that future mass bug closes like this are less likely, please read https://community.kde.org/Get_Involved#Bug_Triaging

Thanks for your understanding!

Nate Graham