Attached encrypted USB drive gets stuck in password prompt

[Cerin]

I used the standard tools in Ubuntu 16 to format and encrypt a large USB hard drive for storing secure backups to. I then used that drive with the standard "Backups" tool to capture periodic backups.

My hard drive recently died, forcing me to re-install Ubuntu 16. The re-install went well, but when I tried to attach the drive to restore my personal files, a modal appeared, prompting me to enter my password.

So I did. And then it prompted me again. I thought I'd mistyped my password, so I re-entered it, making sure my caplocks or numlock key weren't on, but again, it prompted me. After each prompt, the full-screen modal darkened the background until after a dozen attempts, my background was almost completely black. I suspect what's going on is something's trying to access the encrypted disk while I'm typing in the password, and each access is triggering another prompt, effectively locking me out of the system because it's impossible for me to enter a nearly infinite series of prompts.

This bug is a huge problem for two reasons:

1. it locks you out of your computer
2. it prevents you from accessing secure storage and restoring your system

I managed to partially workaround #1 by switching to a terminal and running `export DISPLAY=:0; gnome-shell --replace`. That caused Gnome to reload, which minimized the modal program, allowing me to kill it in the app thumbnail view.

However, that's a huge hassle, and I'm still unable to access any data on encrypted USB drives, even when I enter the password correctly. Please advise.

I don't know exactly what component to file this bug under, so I chose "gnome-shell". Please re-tag it if this is incorrect.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-shell 3.18.5-0ubuntu0.3
ProcVersionSignature: Ubuntu 4.4.0-116.140-generic 4.4.98
Uname: Linux 4.4.0-116-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
Date: Fri Apr 6 00:26:33 2018
DisplayManager: lightdm
InstallationDate: Installed on 2018-03-23 (13 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

I would be interested to see if the problem persists in Ubuntu 17.10 or 18.04 (due for release this month).

17.10.1 release: https://www.ubuntu.com/download/desktop
18.04 pre-release: http://cdimages.ubuntu.com/daily-live/current/

That is likely faster than trying to figure out what component, and if any fix for this issue has been made since 16.04.

[Cerin (chrisspen)]

I use my laptop for development for systems that are standardized on 16.04, so I don't have the option to upgrade at the moment.

Also, I don't think this problem has been in 16.04 for very long. I've attached encrypted drives dozens of times over the last couple years, and have never had this problem. It's only after the last batch of package updates in the last month that now it locks me out.

Do you know what package is responsible for the password prompt shown upon mounting encrypted USB hard drives?

[Daniel van Vugt (vanvugt)]

That depends which password prompt you're talking about. Can you post a photo at all?

P.S. I wasn't recommending upgrading to 17.10/18.04 but you can boot them from USB to test them without installing.

[Cerin (chrisspen)]

I just ran updates, rebooted, and retried, and it worked without issue.

[Daniel van Vugt (vanvugt)]

Fixed then?

[Jehan (jbruggem)]

Same problem here. My complete shell is stuck just because of one, un-closeable modal dialog whose cancel button isn't working.

[Daniel van Vugt (vanvugt)]

Jehan,

This bug is closed. Please open a new bug for your issue, ideally with a screenshot or photo.