nixos-rebuild test (and switch) causes pam_mount to remount

[peterhoeg]

Issue description

Within the last couple of weeks, doing nixos-rebuild test causes pam_mount to remount encrypted home directories and thus asking for passwords. This wasn't the case in the past.

Relevant output:

building '/nix/store/p6bflh7n5zy2dql8l45mix9qnzq65hbk-nixos-system-mildred-18.09.git.98592c5da79M.drv'...
activating the configuration...
setting up /etc...
reenter password for pam_mount:
(mount.c:68): Messages from underlying mount program:
(mount.c:72): crypt_activate_by_passphrase: File exists
(pam_mount.c:522): mount of /dev/mapper/vg0-lv_home_peter failed
kbuildsycoca5 running...

Steps to reproduce

1. Set users.users.some_user.cryptHomeLuks = "/dev/mapper/some_lv";
2. Execute nixos-rebuild test

Technical details

• system: "x86_64-linux"
• host os: Linux 4.17.11, NixOS, 18.09.git.98592c5da79M (Jellyfish)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.0.4
• channels(root): "nixos-18.03pre121670.4cbbecc85db"
• channels(peter): ""
• nixpkgs: /home/peter/src/active/nixpkgs_unstable

[peterhoeg]

Duplicate of #47577.

[peterhoeg]

This isn't actually a duplicate. With the fix in #47842, nixos-rebuild switch still prompts once (versus twice before) so must be another system.activationScript that causes this. This isn't critical though, just annoying.

[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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[peterhoeg]

I've just patched it out locally, but this needs to be fixed properly.

[stale]

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

[stale]

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

[peterhoeg]

keep

[Aleksanaa]

This issue reappleared in nixos unstable and it's the same as you described. And home manager is not working for me if pam mount is set, possibly because related problems. Any ideas? Or should I open a new issue?

[peterhoeg]

So I have been carrying the mentioned patch on my side since this was first mentioned. I have a laptop running unstable with an encrypted home and so far there has been zero problems. Maybe you can share your nixos config?

[Aleksanaa]

So I have been carrying the mentioned patch on my side since this was first mentioned. I have a laptop running unstable with an encrypted home and so far there has been zero problems. Maybe you can share your nixos config?

Do you still have these error indicating pam_mount tries to mount again (not remount):

(mount.c:68): Messages from underlying mount program:
(mount.c:72): Device _dev_nvme0n1p3 already exists.
(mount.c:72): crypt_activate_by_passphrase: File exists
(mount.c:72): Device _dev_nvme0n1p3 is still in use.

When running nixos-rebuild switch?

[peterhoeg]

Yep, but it doesn't matter. The patch simply makes it not prompt for a password when the activation scripts tries to set up the mount, but as it's already there, you get the messages mentioned above, which is ok.