Invalid huge packet received by client when trying to connect

[tc424]

"Received invalid packet: packet size requested is 4609517 but maximum allowed is 4194304"

Server is 2.5.1 (r22431), Xubuntu 16.04.6
Clients are 3.0 HEAD (20190524, r22778), Xubuntu 18.04.2.

Problem manifests from one machine when connected over wifi using python2, but not python3. Similarly, connecting over ethernet seems to be fine.

For some reason, "xpra stop :0" locally on the server also seems to trigger it.

Ordinary client connects didn't see to show much of use in the way of logging, but the xpra stop command showed a huge blob of icon data in the hello packet.

[Antoine Martin]

This is going to be a multi-part thing:

• r22803 warns us when we find icons that are too large (over 16KB by default)
• r22804 we now send the xdg-menu data using a dedicated packet rather than the 'hello' packet if the client supports this new capability

Still TODO:

• now we can also send a new menu when the list of applications is updated
• maybe downsize icons that are too big? (problem is that they're svg... and we don't have python-pillow support for that)

[Antoine Martin]

r22806 watches for changes to the applications menu list and sends the updated definitions to the clients that support the new xdg-menu-update capability.

Tested by moving the xterm definition away and back again:

sudo mv /usr/share/applications/xterm.desktop $HOME/;
sleep 20;
sudo mv $HOME/xterm.desktop  /usr/share/applications/;

(note: there is a slight delay between the time we get notified of changes and the time we actually send the updated menus - that's to prevent the update storms that are common when applying system updates)

Still TODO:

• deal with the big icons somehow
• find a way to backport a fix (these changes are too big)

[tc424]

Is it worth making separate settings for enabling "start new commands (with a command line)" and the new menu? I use the former a lot but doubt I will ever use the latter...

[Antoine Martin]

Is it worth making separate settings for enabling "start new commands (with a command line)" and the new menu? I use the former a lot but doubt I will ever use the latter...

I don't have time for this, sorry.

I think we can close this ticket:

• r22808 fixes "xpra stop": we don't send the xdg-menu data for subcommands like xpra stop since we don't need it, so it doesn't trigger the packet size check
• r22809 removes the icondata if the xdg menu data data would have taken more than half the hello packet budget (will backport)

@tc424: please let me know if this fix works for you (packages will be pushed soon)

[Antoine Martin]

Same "xdg-data" update code added to the html5 client in r22848..

[Antoine Martin]

Caused a bug: #2314, added python3-inotify to recommends in specfile: r22850.

[Antoine Martin]

Feel free to re-open if you still have problems.
The 2.5.2 stable update includes a workaround for this bug.

[Antoine Martin]

See also #2335

[tc424]

The fixes seem to solve my problem, thank you! Though #2340 is probably a knock-on..

[migration script]

this ticket has been moved to: ​https://github.com/Xpra-org/xpra/issues/2310