A mutable user described in 'configuration.nix' gets locked out if an older generation is booted once

[alexeymuranov]

Issue description

I noticed that if i add an existing imperatively created user to users.users, and then boot once into an old generation, the user gets permanently locked out of its account, and i need to log in as a root to set again a password for that user. This is with mutableUsers = true.

Steps to reproduce

1. Create a user imperatively:

# useradd -m test
# passwd test

2. Add this user into /etc/nixos/configuration.nix:

{ # ...
  users.mutableUsers = true;
  users.users.test.isNormalUser = true;
}

And rebuild: nixos-rebuild boot.

3. Reboot and test that the new test user can log in.

4. Reboot into the previous generation and observe that the user test has disappeared from the login menu (in LightDM, for example).

5. Reboot back into the last generation and observe that the password for test user is not accepted anymore.

Technical details

§ nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 4.14.29, NixOS, 18.03pre131587.b6ddb9913f2 (Impala)`
 - multi-user?: `yes`
 - sandbox: `no`
 - version: `nix-env (Nix) 2.0`
 - channels(alexey): `"nixos-17.03-17.03.1949.78e9665b48f, nixos-17.09-17.09.3205.12512f25e9e"`
 - channels(root): `"nixos-18.03pre131587.b6ddb9913f2"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs`

[alexeymuranov]

An additional detail: if, after rebooting into the previous generation, i recreate the user with the same password, then, after rebooting back into the latest generation, the user password is preserved.

[stale]

Thank you for your contributions.

This has been automatically marked as stale because it has had no activity for 180 days.

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[stale]

I marked this as stale due to inactivity. → More info

[alexeymuranov]

still important to me

[stale]

I marked this as stale due to inactivity. → More info

[alexeymuranov]

still important to me