Bug 429784

Summary:	Dragging an icon over another icon causes a crash
Product:	[Plasma] kwin	Reporter:	AK-47 <chkboom>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	crash	CC:	kde, oded
Priority:	NOR	Flags:	chkboom: Wayland+ chkboom: Usability+
Version First Reported In:	5.20.4
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	screencast of a repro attempt

Description AK-47 2020-11-28 23:52:25 UTC

SUMMARY
In many cases, it is possible to cause a crash just by dragging one icon over another.

STEPS TO REPRODUCE
1. Repeatedly tap one of the icons on the task bar until it "sticks" to the cursor, or initiate a drag.
2. Hover the icon over another icon on the task bar.
3. You may have to tap a few times again to let go of the icon.

OBSERVED RESULT
The shell hangs, with suddenly a lot of disk activity, and then eventually the entire desktop including kwin crashes.

EXPECTED RESULT
The icon shouldn't even stick to the mouse in the first place.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Fedora Workstation 33
(available in About System)
KDE Plasma Version: 5.20.3
KDE Frameworks Version: 5.75.0
Qt Version: 5.15.1

ADDITIONAL INFORMATION
Not sure if this is a "kwin" or "plasmashell" bug. It appears kwin is the one that crashes, since I just get a few characters on the screen once it does, but plasmashell might be causing some havoc here.

Comment 1 AK-47 2020-12-28 04:55:24 UTC

Update: Still present in 5.20.4, Qt 5.15.2.
In addition I discovered that this bug appears if you use an application launcher widget, dragging one icon over another (eg. to swap positions?) will do the same thing.

Comment 2 Oded Arbel 2021-09-18 13:33:33 UTC

Created attachment 141675 [details]
screencast of a repro attempt

I'm not sure I'm following the right steps, but I can't repro with dragging task bar entries. I also couldn't repro the "repeated clicking causes cursor to get stuck in drag mode" at all.

Is this still an issue, and if so - can you review the screencast and let me know what I missed in my repro?

Comment 3 David Redondo 2021-09-21 14:04:33 UTC

Needs backtrace or more info

Comment 4 Bug Janitor Service 2021-10-06 04:36:03 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:
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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 5 Bug Janitor Service 2021-10-21 04:35:30 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!