Subject: x2goagent crashes when pasting clipboard contents

From: Tristan Miller <[email-masked]>
Date: Tue, 28 Jul 2020 11:38:49 +0200

Package: x2goserver-x2goagent
Version: 4.1.0.4
Severity: grave

I am running two openSUSE Tumbleweed machines, both with x2goserver
4.1.0.4 (from Git commit gaef470fe) and x2goclient 4.1.2.2, and often
use X2Go in single application mode to connect between them.  Following
a Tumbleweed update on the client machine (from 20200708 to 20200724),
the X2Go connection now disconnects whenever I copy text into the
clipboard on the local machine and then paste it into the remote
machine.  The following error message appears in the system log of the
remote machine:

2020-07-28T11:16:12.479151+02:00 butterfield systemd-coredump[18451]:
Process 17960 (x2goagent) of user 1000 dumped core.#012#012Stack trace
of thread 17960:#012#0  0x00007fdd0c65c4b1 raise (libc.so.6 +
0x3c4b1)#012#1  0x00007fdd0c645539 abort (libc.so.6 + 0x25539)#012#2
0x00007fdd0c69f827 __libc_message (libc.so.6 + 0x7f827)#012#3
0x00007fdd0c72f4f2 __fortify_fail (libc.so.6 + 0x10f4f2)#012#4
0x00007fdd0c72f4c2 __stack_chk_fail (libc.so.6 + 0x10f4c2)#012#5
0x000055ae7290e691 nxagentCollectPropertyEvent (nxagent + 0xb9691)#012#6
 0x000055ae728f54b3 nxagentDispatchEvents (nxagent + 0xa04b3)#012#7
0x000055ae728f9b3a nxagentWakeupHandler (nxagent + 0xa4b3a)#012#8
0x000055ae728ddde3 WaitForSomething (nxagent + 0x88de3)#012#9
0x000055ae728b747a Dispatch (nxagent + 0x6247a)#012#10
0x000055ae728965f6 main (nxagent + 0x415f6)#012#11 0x00007fdd0c646cca
__libc_start_main (libc.so.6 + 0x26cca)#012#12 0x000055ae728989ea _start
(nxagent + 0x439ea)

The Tumbleweed update included some changes to X11/KDE packages that
broke at least one other application (most notably emacsclient) so
perhaps this is also the case here.  (Though according to the openSUSE
bug triagers, the breakage is the other application's fault.)  I am
running KDE on the local machine; I haven't tested if the problem is
reproducible with a different desktop environment.

Detailed steps to reproduce:

1. On the local machine, configure an X2Go connection to a remote
machine to launch a single application such as xfce4-terminal or
konsole, and then launch that connection.

2. On the local machine, use the mouse to select some text in a locally
running application, which will copy it to one of the clipboards.
(Alternatively, copy it to the other clipboard with Ctrl+C or Ctrl+Ins.)

3. On the local machine, switch to the remote window and paste the
contents of the clipboard by middle-clicking. (Alternatively, paste the
other clipboard with Ctrl+V or Shift+Ins.)

At this point the X2Go session will disconnect and the above-noted error
message gets written to the remote machine's system log.