Bug 414389

Summary: kscreenlocker_greeter segfaults when docking/undocking
Product: [Unmaintained] kscreenlocker Reporter: Andrea Scarpino <scarpino>
Component: greeterAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: critical CC: bshah, kde, nate, null, subdiff
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: backtrace

Description Andrea Scarpino 2019-11-22 09:24:45 UTC 
SUMMARY
When the screen is locked, kscreenlocker_greeter segfaults whenever I undock/dock my laptop due to the monitor switch.

STEPS TO REPRODUCE
0. Configure dockd to disable the laptop screen and enable the monitor screen when you dock the laptop.
0. Configure dockd to disable the monitor screen and enable the laptop screen when you undock the laptop.
1. Dock your laptop
2. Lock your screen
3. Undock the laptop
4. Screen is unlocked

kscreenlocker_greeter doesn't crash if I configure dockd to don't disable the laptop screen ever.
I cannot reproduce the crash by using i3lock.

OBSERVED RESULT
$ dmesg
kscreenlocker_g[48914]: segfault at 31 ip 00007f5e3e5f5954 sp 00007ffd3a99d958 error 4 in libQt5Qml.so.5.13.2[7f5e3e3fb000+33c000]

EXPECTED RESULT
kscreenlocker_greeter locks the other monitor without crashing.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.17.3
(available in About System)
KDE Plasma Version: 5.17.3
KDE Frameworks Version: 5.64.0
Qt Version: 5.13.2

ADDITIONAL INFORMATION
Comment 1 Andrea Scarpino 2019-11-26 15:05:03 UTC 
Created attachment 124129 [details]
backtrace

Backtrace.
Comment 2 David Edmundson 2019-11-28 11:16:05 UTC 
Are you in a position to compile your own kscreenlocker?

If so can you add a return at the top of SecComp::init and see if it still happens?
Comment 3 Andrea Scarpino 2019-11-28 14:48:50 UTC 
(In reply to David Edmundson from comment #2)
> If so can you add a return at the top of SecComp::init and see if it still
> happens?

It crashed the same way.
Comment 4 Nate Graham 2021-06-21 21:15:06 UTC 
A lot of multi-screen stuff has changed since this bug report was filed. Can you update to Plasma 5.22 and see if it still happens?
Comment 5 Bug Janitor Service 2021-07-06 04:33:55 UTC 
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 6 Bug Janitor Service 2021-07-21 04:33:39 UTC 
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!