gnome-panel crashed with SIGSEGV in panel_applet_get_xid()

[Uldis Kalniņš]

Tried to add Indicator applet to bottom panel.

ProblemType: Crash
DistroRelease: Ubuntu 14.10
Package: gnome-panel 1:3.8.1-1ubuntu2
ProcVersionSignature: Ubuntu 3.16.0-10.15-lowlatency 3.16.1
Uname: Linux 3.16.0-10-lowlatency x86_64
ApportVersion: 2.14.6-0ubuntu2
Architecture: amd64
CurrentDesktop: Unity
Date: Thu Aug 28 10:49:46 2014
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/gnome-panel
GsettingsChanges:
 b'org.gnome.gnome-panel.run-dialog' b'show-program-list' b'true'
 b'org.gnome.gnome-panel.run-dialog' b'history' b"['/usr/bin/software-center ', 'workrave']"
InstallationDate: Installed on 2013-10-17 (314 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
ProcCmdline: gnome-panel
SegvAnalysis:
 Segfault happened at: 0x7f41ce1ba5a1 <panel_applet_get_xid+17>: mov 0x38(%rbx),%rdx
 PC (0x7f41ce1ba5a1) ok
 source "0x38(%rbx)" (0x00000038) not located in a known VMA region (needed readable region)!
 destination "%rdx" ok
SegvReason: reading NULL VMA
Signal: 11
SourcePackage: gnome-panel
StacktraceTop:
 panel_applet_get_xid () from /usr/lib/libpanel-applet-4.so.0
 ?? () from /usr/lib/libpanel-applet-4.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
 g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
SystemImageInfo: Error: [Errno 2] No such file or directory: 'system-image-cli'
Title: gnome-panel crashed with SIGSEGV in panel_applet_get_xid()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm audio cdrom dip disk fuse libvirtd lpadmin plugdev sambashare sudo vboxusers

[Apport retracing service (apport)]

StacktraceTop:
 panel_applet_get_xid (applet=0x0, screen=0x1ec8110) at panel-applet.c:2721
 panel_applet_factory_get_applet (invocation=<optimized out>, parameters=<optimized out>, connection=<optimized out>, factory=<optimized out>) at panel-applet-factory.c:165
 method_call_cb (connection=0x1ec8110, sender=0x1ec8110 "\300\071\354\001", object_path=0x1 <error: Cannot access memory at address 0x1>, interface_name=0x1 <error: Cannot access memory at address 0x1>, method_name=0x0, parameters=0x7ffffd071800, invocation=0x7f41c8017f40, user_data=0x20b7d00) at panel-applet-factory.c:185
 call_in_idle_cb (user_data=0x7f41c8017f40) at /build/buildd/glib2.0-2.41.3/./gio/gdbusconnection.c:4884
 g_main_dispatch (context=0x1eaeed0) at /build/buildd/glib2.0-2.41.3/./glib/gmain.c:3064

[Dmitry Shachnev (mitya57)]

Thanks for your report. Is this reproducible? I am also using 14.10 amd64, and I don't get any crash when adding indicator-applet to the bottom panel.

The stacktrace indicates it may be a random failure or a bug somewhere else.

[Dmitry Shachnev (mitya57)]

Actually I just got a similar crash myself when trying to add a clock applet.

[Dmitry Shachnev (mitya57)]

I can reliably reproduce this when adding, removing and adding again "Fish" or "Clock" applets. Alberts, what do you think?

[Alberts Muktupāvels (muktupavels)]

Not sure what is wrong. I can reproduce on ubuntu 14.04, but not on 14.10, but that is probably because I am not using gnome-panel from ubuntu packages.

I have no time to debug this now.

[Dmitry Shachnev (mitya57)]

This happens only when the applet is in-process. If I remove --with-in-process-applets=all from rules, this crash no longer occurs.

Also, just before the crash happens, I get this warning:

Failed to register object /org/gnome/panel/applet/ClockAppletFactory: An object is already exported for the interface org.gnome.panel.applet.AppletFactory at /org/gnome/panel/applet/ClockAppletFactory