VBox crashes if LibreOffice starts

[craig100]

Hi,

With Linux Mint (LM) 19.3 if I have VBox 6.1.10 r138449 (Qt5.9.5) running a Windows 10 guest and then start up LibreOffice v6.0.7.3 on the host, 1 minute later VBox crashes. If I then start up VBox and it's W10 guest, after login, it crashes as the screen becomes usable (i.e. the little caret appears on the W10 taskbar with the Defender and Guest Additions). I can only start VBox and it's W10 guest successfully after a full reboot.

I'm a Windows web developer and have worked this way on LM for a decade. This has only happened in the last couple of days and I'm desperate to get it working again. LM is and W10 are both up to date with their latest patches, etc. Can someone please help me troubleshoot this so I have a chance of fixing it?

My system info: Kernel: 5.3.0-61-generic x86_64 bits: 64 compiler: gcc v: 7.5.0
Desktop: Cinnamon 4.4.8 wm: muffin dm: LightDM Distro: Linux Mint 19.3 Tricia
base: Ubuntu 18.04 bionic

Thanks.

Craig

[scottgus1]

I'm not sure I'd know how to fix this, but anyone who does is going to need a guest log.

Start the guest from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.

Right-click the guest in the main Virtualbox window's guest list, choose Show Log. Save the far left tab's log, zip it, and post the zip file, using the forum's Upload Attachment tab.

[craig100]

Here's the log generated as you described. The failure was selected a cell in a Libre Office Calc spreadsheet and pressing Ctrl+C.

Any advice or observations would be appreciated if you can.

Thanks.

[scottgus1]

Your guest has shared clipboard enabled, and you report that the crash happened when doing Ctrl-C (clipboard Copy?) in Libre Office.

What happens under these tests:
Ctrl-C in a guest text editor
Ctrl0C in LibreOffice with shared clipboard disabled

[craig100]

Good points.

Ctrl+C in W10 Guest : no issues.

Ctrl+C in LibreOffice Calc with VM's Shared Clipboard disabled : no issues.

So it would appear it's something to do with the Shared Clipboard.

I know that I updated the Hosts Nvidia GPU Driver a few days ago and since then the background on the 2nd VM screen only covers the bottom half of the screen. I make a point of reinstalling the VBox Guest Additions after any updates in the Guest. I switched back to the Intel GPU to see if that made a difference but it didn't.

Thanks.

[scottgus1]

One thing I just noticed, Libre Office is on the host. Can you please try a couple more tests, with Virtualbox shared clipboard enabled?

Try Ctrl-C in a text editor on the host, too, while the Windows 10 guest is running. See if you can copy/paste back and forth between the host's text editor and Windows Notepad.

Also try Ctrl-C in the host's Libre Office and the guest running with 3D acceleration disabled.

[craig100]

Sorry for the delay.

1) Ctrl-C in a text editor on the host, too, while the Windows 10 guest is running. See if you can copy/paste back and forth between the host's text editor and Windows Notepad : Works fine

2) Ctrl-C in the host's Libre Office and the guest running with 3D acceleration disabled: Still causes a crash. BUT interestingly, 3D Accel OFF fixes the background issue on the 2nd screen. Background is now full height.

[scottgus1]

Thanks for the test results!
That #1 works shows that basic shared clipboard is still working.

It seems like a conflict occurs in the Calc data that Libre Office wants to put on the clipboard. I wonder if Ctrl-C in Libre Office's word processor succeeds or fails?

My idea on disabling 3D was from the Nvidia update you did recently. Nvidia released adrivers with a file that was not security-signed correctly, which was causing some issues with Virtualbox hardening on Windows hosts. Too bad that the fix wasn't that easy.

VirtualBox's shared clipboard is for text only, though some formats of copied image data can be copied too. Looks like Libre Office's Calc data found a hole in Virtualbox's shared clipboard code.

Try posting this on the Bugtracker. Put a link back to this post, and give a guest log with the various copy/paste tests you've done, culminating in Libre Office Calc.