After some more digging and having reproduced the issue a few more times, here is what seems to happen.
Seahorse is running, using the avahi library. Seahorse has called avahi_glib_poll_new() and some AvahiTimeout timeouts have been created. Then things are stopped because the computer is about to be rebooted. Seahorse is closing down and therefore does some cleanup, among other things it calls avahi_glib_poll_free() which calls cleanup_timeouts() which destroys all the timeouts. However, after the timeouts were destroyed, there still exists a pointer to one of those timeouts in the dispatch_timeout member in a ConnectionData struct. For some reason the dispatch_timeout_callback() function is called at this point, and it does "ConnectionData *d = userdata" and that ConnectionData struct has inside it a dispatch_timeout pointer which is now invalid because the timeout was destroyed, its memory was freed, as a result of the avahi_glib_poll_free() call earlier. dispatch_timeout_callback() passes the ConnectionData *d to request_dispatch() which calls timeout_update() passing the invalid d->dispatch_timeout pointer, which is then used and happens to point to some garbage which gives the assertion failure. Not sure exactly how to fix the problem, but it seems bad that pointers to destroyed data structures are still lying around, maybe things should be destroyed in a different order. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to avahi in Ubuntu. https://bugs.launchpad.net/bugs/1820584 Title: seahorse assert failure: seahorse: glib-watch.c:195: timeout_update: Assertion `!t->dead' failed. Status in avahi package in Ubuntu: Confirmed Bug description: --------------------------------------------------------- Description: Ubuntu Disco Dingo (development branch) Release: 19.04 --------------------------------------------------------- seahorse: Installed: 3.32-1 Candidate: 3.32-1 Version table: *** 3.32-1 500 500 http://br.archive.ubuntu.com/ubuntu disco/main amd64 Packages 100 /var/lib/dpkg/status --------------------------------------------------------- I have absolutely no idea why or how. Just collected this report from apport-cli. Some times receiving "internal error" reports, no details provided, just "Cancel" or "Send report" options. So, I decided to check apport and there was this report. ProblemType: Crash DistroRelease: Ubuntu 19.04 Package: seahorse 3.32-1 ProcVersionSignature: Ubuntu 5.0.0-7.8-generic 5.0.0 Uname: Linux 5.0.0-7-generic x86_64 NonfreeKernelModules: nvidia_modeset nvidia ApportVersion: 2.20.10-0ubuntu23 Architecture: amd64 AssertionMessage: seahorse: glib-watch.c:195: timeout_update: Assertion `!t->dead' failed. CurrentDesktop: ubuntu:GNOME Date: Sun Mar 17 18:09:01 2019 ExecutablePath: /usr/bin/seahorse InstallationDate: Installed on 2019-03-17 (0 days ago) InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Alpha amd64 (20190316) ProcCmdline: /usr/bin/seahorse --gapplication-service Signal: 6 SourcePackage: seahorse StacktraceTop: __assert_fail_base (fmt=0x7f733ae49588 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x7f733aecf02d "!t->dead", file=0x7f733aecf000 "glib-watch.c", line=195, function=<optimized out>) at assert.c:92 __GI___assert_fail (assertion=0x7f733aecf02d "!t->dead", file=0x7f733aecf000 "glib-watch.c", line=195, function=0x7f733aecf1d8 "timeout_update") at assert.c:101 ?? () from /lib/x86_64-linux-gnu/libavahi-glib.so.1 ?? () from /lib/x86_64-linux-gnu/libavahi-client.so.3 ?? () from /lib/x86_64-linux-gnu/libavahi-glib.so.1 Title: seahorse assert failure: seahorse: glib-watch.c:195: timeout_update: Assertion `!t->dead' failed. UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo separator: To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1820584/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
