/usr/bin/gnome-software:11:g_type_check_instance:g_signal_emit_valist:g_signal_emit:g_closure_invoke:signal_emit_unlocked_R

The crash seems to be related to a ComboBox and has only started occurring in Xenial after the Snap interfaces support was added.

Cause seems to be a name collision for the GsPermissionComboBox "changed" signal - solution was to rename it to "value-changed". This only occurs when a snap has a plug that can connect to more than one slot.

Asked on forum if anyone knows a suitable snap to test this:
https://forum.snapcraft.io/t/searching-for-a-snap-that-has-a-plug-with-multiple-slots

This bug was fixed in the package gnome-software - 3.29.1-0ubuntu2

---------------
gnome-software (3.29.1-0ubuntu2) cosmic; urgency=medium

  * debian/control:
    - Bump minimum version of snapd-glib
  * debian/patches/0014-Add-a-basic-permissions-system.patch:
    - Fix crash when have plugs with multiple slots available (LP: #1778160)

 -- Robert Ancell <email address hidden> Fri, 22 Jun 2018 15:44:13 +1200

>
[Regression Potential]
Fix is to rename a signal to avoid a name collision, low chance of introducing new bugs.

Please update that to inform testers where to look for new bugs if the change does happen to introduce any.

>
Asked on forum if anyone knows a suitable snap to test this:
https://forum.snapcraft.io/t/searching-for-a-snap-that-has-a-plug-with-multiple-slots

Looks like you got an answer there on how to reproduce? Accepting for now, but please verify using that method (or by finding the culprit snap that causes user crashes) for SRU verification.

Hello errors.ubuntu.com, or anyone else affected,

Accepted gnome-software into bionic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gnome-software/3.28.1-0ubuntu4.18.04.2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-bionic to verification-done-bionic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-bionic. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

I tried with the snaps from James directory as mentioned in the forums thread but cannot reproduce this crash with any of them and the version of gnome-software in bionic updates.

However looking at errors.u.c there is no occurrence of this crash for the version of gnome-software with this fix in cosmic and bionic-proposed. Based on this I'm marking this SRU as verified.

This bug was fixed in the package gnome-software - 3.28.1-0ubuntu4.18.04.2

---------------
gnome-software (3.28.1-0ubuntu4.18.04.2) bionic; urgency=medium

  [ Robert Ancell ]
  * debian/patches/0014-Add-a-basic-permissions-system.patch:
    - Fix crash when have plugs with multiple slots available (LP: #1778160)

  [ Andrea Azzarone ]
  * debian/patches/0001-snap-plugin-segfault.patch:
    - don't segfault on null snap installation date (lp: #1781996)

 -- Sebastien Bacher <email address hidden> Thu, 19 Jul 2018 17:10:17 +0200

The verification of the Stable Release Update for gnome-software has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

An upload of gnome-software to xenial-proposed has been rejected from the upload queue for the following reason: "Since this upload includes the same change for 'new media API' as others, I would feel much safer if we set a minimal version depenency to libsnapd-glib-dev (>= 1.45) - since it seems there was more than one snapd-glib version in xenial.".

Hello errors.ubuntu.com, or anyone else affected,

Accepted gnome-software into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gnome-software/3.20.5-0ubuntu0.16.04.12 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

Tested gnome-software 3.20.5-0ubuntu0.16.04.12 and able to connect / disconnect interfaces.

This bug was fixed in the package gnome-software - 3.20.5-0ubuntu0.16.04.12

---------------
gnome-software (3.20.5-0ubuntu0.16.04.12) xenial; urgency=medium

  * debian/patches/0001-Fix-potential-crash-when-icons-are-missing.patch:
    - Fix crash loading icons (LP: #1778135)
  * debian/patches/0020-Add-a-basic-permissions-system.patch:
    - Fix crash when have plugs with multiple slots available (LP: #1778160)
  * debian/patches/0021-Add-a-Snap-plugin.patch
    - Fix some command line warnings (LP: #1790563)
    - Use new snapd media API (LP: #1799614)
    - Allow connections on the u2f-devices interface (LP: #1738164)
  * debian/patches/0053-Don-t-reject-unexpected-state-changes-external-event.patch:
    - Fix snaps not being shown correctly after install from command line
      (LP: #1754655)
  * debian/patches/0054-Show-verified-developers.patch:
    - Show verified developers (LP: #1789336)

 -- Robert Ancell <email address hidden> Wed, 17 Apr 2019 14:39:52 +1200