gpg --batch --verify during maas install causes Unhandled Error

[John George]

After MAAS installation regiond.log shows an Unhandled Error and exception for:
subprocess.CalledProcessError: Command '['gpg', '--batch', '--verify', u'--keyring=/tmp/maas-fzuCCukeyrings/maas.ubuntu.com-images-ephemeral-v2-releases.gpg', '-']' returned non-zero exit status -15

Reproducible by installing 1.9.3 from ppa:maas/stable

Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-===================================-================================-============-===============================================================================
ii maas 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server all-in-one metapackage
ii maas-cli 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS command line API tool
ii maas-cluster-controller 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server cluster controller
ii maas-common 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server common files
ii maas-dhcp 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS DHCP server
ii maas-dns 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS DNS server
ii maas-enlist 0.4+bzr38-0ubuntu1 amd64 MAAS enlistment tool
ii maas-proxy 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS Caching Proxy
ii maas-region-controller 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server complete region controller
ii maas-region-controller-min 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS Server minimum region controller
ii python-django-maas 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server Django web framework
ii python-maas-client 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS python API client
ii python-maas-provisioningserver 1.9.3+bzr4577-0ubuntu1~trusty1 all MAAS server provisioning libraries

[Mike Pontillo (mpontillo)]

I tested this quickly on MAAS 2.0 ~b6 and didn't see the problem there.

Checking `man gpg`:

"""
RETURN VALUE

The program returns 0 if everything was fine, 1 if at least a signature was bad, and other error codes for fatal errors.
"""

So for whatever reason, this GPG verify operation is failing. I'd need to look into how this happens and what exactly we're verifying.

After looking at the log, it looks like the error is from simplestreams. I'm guessing the GPG signature of the image descriptions did not properly verify, but I'd have to check the code.

Here's the backtrace:

https://paste.ubuntu.com/16928395/

[Mike Pontillo (mpontillo)]

It seems like simplestreams should raise something nicer than CalledProcessError if this happens.

[Launchpad Janitor (janitor)]

[Expired for MAAS because there has been no activity for 60 days.]