msmtp: unconditional debconf promp on upgrade to Lunar

[Simon Chopin]

[Impact]

When upgrading to lunar from kinetic, there's a debconf prompt to warn the user that the binary isn't setGID anymore, so system-wide configuration won't work anymore. While that prompt is worthwhile for people who actually used system-wide configuration, it shouldn't be triggered for users that only have local user config in their $HOME.

[Test plan]

In a fresh Kinetic container:

sudo apt install msmtp
do-release-upgrade -p # don't forget to enable -proposed

-> This should *NOT* have the msmtp SetGID debconf prompt

IN another fresh container:

sudo apt install msmtp
touch /etc/msmtprc
do-release-upgrade -p

-> This should trigger the debconf prompt

[ Where problems could occur ]

The fix could hide the warning in cases where users legitimately need to see it, leading to loss of functionality or even local security issues (use of insecure defaults that were corrected in the systemwide configuration).

[Other info]

For reference, the prompt in question:

┌───────────────────────────┤ Configuration de msmtp ├────────────────────────────┐
│ │
│ Remove SetGID bit on msmtp │
│ │
│ Starting from version 1.8.22, msmtp will no longer be SetGID. Hence the │
│ creation of the system-wide configuration (/etc/msmtprc) using debconf is │
│ removed. │
│ . │
│ From one side, using the system wide configuration implied msmtp to be SetGID │
│ but recent security hardening changes in GLib prevent SetGID binaries built │
│ against libsecret to talk to the D-Bus session, and therefore prevent it from │
│ being able to retrieve passwords from gnome-keyring or KWallet. │
│ . │
│ On another side, it was easy for a local user to obtain the credentials │
│ stored in /etc/msmtprc even if the file was not readable for this user when │
│ msmtp was SetGid. │
│ . │
│ More information in the following bug reports: │
│ - https://bugs.debian.org/944188 │
│ - https://bugs.debian.org/995012 │
│ │
│ <Ok> │
│ │
└─────────────────────────────────────────────────────────────────────────────────┘

[Simon Chopin (schopin)]

I have to upload the fix in Lunar before fixing it in devel since the archive isn't open yet. I'm forwarding the fix to Debian, hoping that it'll make it there and will be synced back.

[Robie Basak (racb)]

Hello Simon, or anyone else affected,

Accepted msmtp into lunar-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/msmtp/1.8.23-1ubuntu0.1 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, what testing has been performed on the package and change the tag from verification-needed-lunar to verification-done-lunar. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-lunar. 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.

[Ubuntu SRU Bot (ubuntu-sru-bot)]

All autopkgtests for the newly accepted msmtp (1.8.23-1ubuntu0.1) for lunar have finished running.
The following regressions have been reported in tests triggered by the package:

altermime/0.3.10-12 (amd64)
backuppc/4.4.0-8 (amd64)
courier/1.0.16-3build5 (amd64)
cyrus-imapd/3.6.1-2ubuntu1 (amd64)
fwlogwatch/1.4-4 (amd64)
iwatch/0.2.2-10 (amd64)
sbuild/0.85.0ubuntu2 (amd64, arm64, armhf, ppc64el, s390x)

Please visit the excuses page listed below and investigate the failures, proceeding afterwards as per the StableReleaseUpdates policy regarding autopkgtest regressions [1].

https://people.canonical.com/~ubuntu-archive/proposed-migration/lunar/update_excuses.html#msmtp

[1] https://wiki.ubuntu.com/StableReleaseUpdates#Autopkgtest_Regressions

Thank you!

[Launchpad Janitor (janitor)]

This bug was fixed in the package msmtp - 1.8.23-1ubuntu1

---------------
msmtp (1.8.23-1ubuntu1) mantic; urgency=medium

  * Disable the security-information debconf prompt in the absence of
    system-wide configuration (LP: #2017759)

 -- Simon Chopin <email address hidden> Wed, 03 May 2023 11:08:20 +0200

[Andreas Hasenack (ahasenack)]

Hello Simon,

this bug has been unverified for quite some time, do you think you could perform the verification?

[Simon Chopin (schopin)]

Erf, I'd forgotten about that and apparently the "stuck in proposed" messages that usually remind me of this were caught by Gmail spam filter.

Verified, with some tweaks to the formula: do-release-upgrade -p doesn't do what I thought it did, so instead I had to revert to doing a manual dist-upgrade à la Debian.

[Launchpad Janitor (janitor)]

This bug was fixed in the package msmtp - 1.8.23-1ubuntu0.1

---------------
msmtp (1.8.23-1ubuntu0.1) lunar; urgency=medium

  * Disable the security-information debconf prompt in the absence of
    system-wide configuration (LP: #2017759)

 -- Simon Chopin <email address hidden> Wed, 26 Apr 2023 15:03:45 +0200

[Andreas Hasenack (ahasenack)]

The verification of the Stable Release Update for msmtp has completed successfully and the package is now being 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.