mate-panel crashes in mate_panel_applet_locked_change_notify on moving/removing applets

[Donal P. O'Sullivan]

I had 'MATE Tweak' open on the Desktop.
I just 'clicked-on' Plank, then I started to 'Drag' items onto the Plank Menu,
then I got the error message...
That's it!!

ProblemType: Crash
DistroRelease: Ubuntu 16.04
Package: mate-panel 1.12.2-1
ProcVersionSignature: Ubuntu 4.4.0-14.30-generic 4.4.5
Uname: Linux 4.4.0-14-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
CrashCounter: 1
CurrentDesktop: MATE
Date: Mon Mar 21 15:08:09 2016
ExecutablePath: /usr/bin/mate-panel
InstallationDate: Installed on 2016-03-20 (1 days ago)
InstallationMedia: Ubuntu-MATE 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160224)
ProcCmdline: mate-panel --replace
ProcEnviron:
 LANGUAGE=en_IE:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_IE.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7fa16d3e28f0 <g_type_check_instance_cast+32>: mov (%r10),%rbp
 PC (0x7fa16d3e28f0) ok
 source "(%r10)" (0x00000040) not located in a known VMA region (needed readable region)!
 destination "%rbp" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: mate-panel
StacktraceTop:
 g_type_check_instance_cast () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 panel_widget_get_applet_locked ()
 ?? ()
 g_cclosure_marshal_VOID__STRINGv () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
Title: mate-panel crashed with SIGSEGV in g_type_check_instance_cast()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo

[Apport retracing service (apport)]

StacktraceTop:
 g_type_check_instance_cast () from /tmp/apport_sandbox_uf6sw0/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 panel_widget_get_applet_locked ()
 mate_panel_applet_locked_change_notify ()
 g_cclosure_marshal_VOID__STRINGv () from /tmp/apport_sandbox_uf6sw0/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 _g_closure_invoke_va () from /tmp/apport_sandbox_uf6sw0/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Vlad Orlov (monsta)]

Random crashes in mate_panel_applet_locked_change_notify are now fixed upstream in 1.18.5.

https://github.com/mate-desktop/mate-panel/commit/418679a91ff711170754ce4d6ed9105e3ae6449b

[Martin Wimpress  (flexiondotorg)]

Fixed in mate-panel 1.18.5-1