sudo: PAM authentication error: Module is unknown

JasonZhang · 2015-11-12 07:00:51

After I `yaourt -S pam gpm`, I can't login/ssh to my laptop.
Also `sudo su root`, it just prints out 'sudo: PAM authentication error: Module is unknown'

/var/log/pacman.log:

[2015-11-12 14:39] [PACMAN] Running 'pacman --color auto -S extra/libva-mesa-driver extra/libevdev'
[2015-11-12 14:39] [ALPM] transaction started
[2015-11-12 14:39] [ALPM] upgraded libva-mesa-driver (11.0.4-1 -> 11.0.5-1)
[2015-11-12 14:39] [ALPM] upgraded libevdev (1.4.4-1 -> 1.4.5-1)
[2015-11-12 14:39] [ALPM] transaction completed
[2015-11-12 14:41] [PACMAN] Running 'pacman --color auto -S core/pam core/gpm'
[2015-11-12 14:41] [ALPM] transaction started
[2015-11-12 14:41] [ALPM] upgraded pam (1.2.1-1 -> 1.2.1-2)
[2015-11-12 14:41] [ALPM] upgraded gpm (1.20.7-5 -> 1.20.7-6)
[2015-11-12 14:41] [ALPM] transaction completed

How can I fix this up? I can't even roll back to older version of pam.
Can I reboot to single user mode?

Also, why does this update cause this problem?

Thank you.

Last edited by JasonZhang (2015-11-12 07:02:41)

Scimmia · 2015-11-12 07:03:11

Update your system, partial updates are not supported. If you ever run pacman -Sy, you're probably doing it wrong.

JasonZhang · 2015-11-12 07:04:51

@Scimmia, thanks for your reply.

But sometimes I don't want to update some programs which may have different behaviors to the older version or something else.

Scimmia · 2015-11-12 07:06:02

JasonZhang wrote:

@Scimmia, thanks for your reply.
But sometimes I don't want to update some programs which may have different behaviors to the older version or something else.

Then you're using the wrong distro. If you do partial updates, things like this happen. You're on your own.

JasonZhang · 2015-11-12 07:07:46

Scimmia wrote:

JasonZhang wrote:
@Scimmia, thanks for your reply.
But sometimes I don't want to update some programs which may have different behaviors to the older version or something else.
Then you're using the wrong distro. If you do partial updates, things like this happen. You're on your own.

Emm, but how can I fix this issue up?

jasonwryan · 2015-11-12 07:08:04

Not a Sysadmin issue, moving to NC...

Scimmia · 2015-11-12 07:08:33

Like I said, by updating your system. You may have to boot to a live CD and use pacman --root to do it.

JasonZhang · 2015-11-12 07:13:06

Scimmia wrote:

Like I said, by updating your system. You may have to boot to a live CD and use pacman --root to do it.

I'll have a try. Thank you.

quequotion · 2015-11-14 15:26:58

I have this error from nowhere and nothing in the middle of an upgrade (not a partial upgrade--in the middle of the actual upgrade process).

I need a solution that does not involve rebooting, as there's a good chance the system will not be recoverable.

I tried to login as root, but this resulted in "login incorrect" before asking for a password.

EDIT: The last successful use of sudo occured when installing libtirpc during the upgrade. I highly suspect this package is broken, which was a known problem in [testing] as of June.

Last edited by quequotion (2015-11-14 15:37:24)

Scimmia · 2015-11-14 15:36:43

quequotion wrote:

I have this error from nowhere and nothing in the middle of an upgrade (not a partial upgrade--in the middle of the actual upgrade process).

What upgrade process would that be?

If you're stuck as non-root without working pam, I don't know what else you can do.

quequotion · 2015-11-14 15:41:12

Scimmia wrote:

If you're stuck as non-root without working pam, I don't know what else you can do.

If a functional libtirpc package exists, I can install it with pacstrap from the live cd, but it's a bit of a gamble.

I do not believe a working package exists; I suspect the problem that appeared in testing has passed into the repositories and lots of people are about to have broken PAM.

Last edited by quequotion (2015-11-14 15:42:53)

Scimmia · 2015-11-14 15:42:45

Nope, current libtirpc works fine. I've been running it for over a week.

The issue is upgrading it without upgrading pam (ie, partial update).

Last edited by Scimmia (2015-11-14 15:45:56)

quequotion · 2015-11-15 02:21:14

Scimmia wrote:

What upgrade process would that be?

The kind you don't expect to leave you with a bricked computer.

I was able to get back to a usable state. I rebooted to the livecd and reinstalled libtirpc with pacstrap but that wasn't enough because the unfinished upgrade had left many version descrepancies, breaking systemd, gnome, etc.

What is wrong with libtirpc? It looks like I found whatever was going on in [testing] back in June, but maybe it only comes out when building from ABS.

Scimmia · 2015-11-15 06:10:09

quequotion wrote:

Scimmia wrote:
What upgrade process would that be?
The kind you don't expect to leave you with a bricked computer.

Specifically?

If you mean building a package, installing it, then building another, that's an unsupported partial update and this kind of breakage is expected.

quequotion · 2015-11-15 07:03:16

Scimmia wrote:

that's an unsupported partial update and this kind of breakage is expected.

Rather than play 20 questions, when we both know you're just looking for an excuse to do nothing and that you will find it; why not consider that there is something very dangerous going on with this package and it's in everyone's best interest to do something about it.

Just because it doesn't happen under perfect conditions with the specific version packaged now doesn't mean it won't later or in another version of this package, and it's really dangerous.

Example: If there were a hand grenade under my pillow, but the pin had not been pulled, I could probably sleep on it safely--but I wouldn't.

Last edited by quequotion (2015-11-15 07:09:07)

Scimmia · 2015-11-15 07:15:11

I'm just using the fact that I happen to know that you like to build everything on your system without actually knowing what you're doing.

So answer this simple question: Did you run pacman -Syu and update libtirpc at the same time as all packages that depend on it?

Last edited by Scimmia (2015-11-15 07:16:12)

ewaller · 2015-11-15 07:18:36

Okay guys, rein it in a little.
https://wiki.archlinux.org/index.php/Fo … ther_users

Last edited by ewaller (2015-11-15 07:18:56)

quequotion · 2015-11-15 14:18:03

ewaller wrote:

rein it in a little.

Sorry if it sounded contentious, I don't mean to start a fight.

Scimmia wrote:

you like to build everything on your system without actually knowing what you're doing

There are many reasons why I do this, one of them is to find more bugs, another is to learn more about the individual packages.

I'm willing to go through a lot to contribute to better packages; even if my opinion of "better" isn't required by arch standards.

Last edited by quequotion (2015-11-15 14:18:41)

Scimmia · 2015-11-15 17:33:55

And you still won't answer the question.

quequotion · 2015-11-15 20:17:27

Scimmia wrote:

And you still won't answer the question.

I was pretty sure you'd already understood that I was upgrading by building the packages from source.

If you really need something to point at and say "see that's exactly why..." then yes, I was upgrading with "yaourt -Syub". Just one b; I skipped building dependencies as well this time.

I don't see why it's invalid to ask what in libtirpc could be potentially causing a serious problem anyway, as it does seem to cause this problem under certain conditions ([testing] build, incomplete upgrades, etc) and given that Arch is a rolling release that most users upgrade manually, every single installation exists at a different stage of (partial) upgrade. I find it important to know why this isn't affecting standard installations when it is very easy to trigger; the possibility that this particular package has potential for catastrophic failure seems worth investigating....

Was there ever a followup after the package was pulled from [testing] in June?

jasonwryan · 2015-11-15 20:26:13

quequotion wrote:

Arch is a rolling release that most users upgrade manually, every single installation exists at a different stage of (partial) upgrade.

This is only true for people that don't -Syu: which is why it is unsupported. The Arch model depends upon full system upgrades.

Scimmia · 2015-11-15 20:30:59

quequotion wrote:

Scimmia wrote:
And you still won't answer the question.
I was pretty sure you'd already understood that I was upgrading by building the packages from source.
If you really need something to point at and say "see that's exactly why..." then yes, I was upgrading with "yaourt -Syub". Just one b; I skipped building dependencies as well this time.

So yes, your entire problem comes from the partial update. This is not supported for exactly this reason.

quequotion wrote:

I don't see why it's invalid to ask what in libtirpc could be potentially causing a serious problem anyway

It doesn't, though. It's a soname bump the same as hundreds of soname bumps that Arch has had.

quequotion wrote:

as it does seem to cause this problem under certain conditions ([testing] build, incomplete upgrades, etc) and given that Arch is a rolling release that most users upgrade manually, every single installation exists at a different stage of (partial) upgrade.

This is flat out false. A partial upgrade is when you update a library or program without updating everything else on your system to the most current version available at exactly the same time. No Arch installations should exist in this state.

quequotion wrote:

I find it important to know why this isn't affecting standard installations when it is very easy to trigger; the possibility that this particular package has potential for catastrophic failure seems worth investigating....
Was there ever a followup after the package was pulled from [testing] in June?

It was fixed immediately.
https://projects.archlinux.org/svntogit … 89441b01d0
This has nothing to do with that at all.

amaro · 2015-11-28 17:19:35

I had this problem recently. I fixed it from an existing LMDE I have on a different partition.
I boot into LMDE

$ su root
# fdisk -l
/dev/sda4       446341120 976773119 530432000   253G 83 Linux
# mkdir /mnt/sda4
# mount /dev/sda4 /mnt/sda4
# cd /mnt/sda4
# mount -t proc proc proc/
# mount --rbind /sys sys/
# mount --rbind /dev dev/
# cp /etc/resolv.conf etc/resolv.conf
# chroot /mnt/sda4
# pacman -Syyu
:: Proceed with installation? [Y/n] y
# exit
# cd /
# umount --recursive /mnt/sda4/
# reboot

Last edited by amaro (2015-11-30 13:44:07)

quequotion · 2015-11-30 10:50:10

amaro wrote:

I had this problem recently. I fixed it from an existing LMDE I have on a different partition.

This is a very helpful reply, and it reminds me that we might need a wiki page especially for ways to recover "bricked" installations.

WorMzy · 2015-11-30 10:56:24

We already do. See https://wiki.archlinux.org/index.php/Change_root

Arch Linux

#1 2015-11-12 07:00:51

sudo: PAM authentication error: Module is unknown

#2 2015-11-12 07:03:11

Re: sudo: PAM authentication error: Module is unknown

#3 2015-11-12 07:04:51

Re: sudo: PAM authentication error: Module is unknown

#4 2015-11-12 07:06:02

Re: sudo: PAM authentication error: Module is unknown

#5 2015-11-12 07:07:46

Re: sudo: PAM authentication error: Module is unknown

#6 2015-11-12 07:08:04

Re: sudo: PAM authentication error: Module is unknown

#7 2015-11-12 07:08:33

Re: sudo: PAM authentication error: Module is unknown

#8 2015-11-12 07:13:06

Re: sudo: PAM authentication error: Module is unknown

#9 2015-11-14 15:26:58

Re: sudo: PAM authentication error: Module is unknown

#10 2015-11-14 15:36:43

Re: sudo: PAM authentication error: Module is unknown

#11 2015-11-14 15:41:12

Re: sudo: PAM authentication error: Module is unknown

#12 2015-11-14 15:42:45

Re: sudo: PAM authentication error: Module is unknown

#13 2015-11-15 02:21:14

Re: sudo: PAM authentication error: Module is unknown

#14 2015-11-15 06:10:09

Re: sudo: PAM authentication error: Module is unknown

#15 2015-11-15 07:03:16

Re: sudo: PAM authentication error: Module is unknown

#16 2015-11-15 07:15:11

Re: sudo: PAM authentication error: Module is unknown

#17 2015-11-15 07:18:36

Re: sudo: PAM authentication error: Module is unknown

#18 2015-11-15 14:18:03

Re: sudo: PAM authentication error: Module is unknown

#19 2015-11-15 17:33:55

Re: sudo: PAM authentication error: Module is unknown

#20 2015-11-15 20:17:27

Re: sudo: PAM authentication error: Module is unknown

#21 2015-11-15 20:26:13

Re: sudo: PAM authentication error: Module is unknown

#22 2015-11-15 20:30:59

Re: sudo: PAM authentication error: Module is unknown

#23 2015-11-28 17:19:35

Re: sudo: PAM authentication error: Module is unknown

#24 2015-11-30 10:50:10

Re: sudo: PAM authentication error: Module is unknown

#25 2015-11-30 10:56:24

Re: sudo: PAM authentication error: Module is unknown

Board footer