Pam_mount is failing to mount filesystems when the mount point is a polyinstantiated directory.

The problem is only when the polydir itself is used as a mountpoint; there is no problem using a subdirectory inside the polydir. (e.g. If "/data2" is defined as a polydir in /etc/security/pam_namespace.conf, pam_mount succeeds when using /data2/subdir as a mount point, but fails when using /data2 as the mount point.)

When the mount fails, lines like the following are logged by both systemd and login (with debugging enabled in pam_mount.conf.xml):

(mount.c:250): Mount info: globalconf, user=elinde <volume fstype="cifs" server="stor1" path="data" mountpoint="/data2" cipher="(null)" fskeypath="(null)" fskeycipher="(null)" fskeyhash="(null)" options="multiuser,cruid=elinde,sec=krb5,cifsacl" /> fstab=0 ssh=0

(mount.c:622): data already seems to be mounted at /data2, skipping

This bug doesn't exist in the upstream pam-mount project, but was introduced with the patch 0014-Don-t-compare-source-when-checking-if-it-s-already-m.patch starting in Debian's 2.16-4 release (made to address https://bugs.debian.org/799752 and similar issues with encrypted volumes). This bug is also reported for Ubuntu: https://bugs.launchpad.net/ubuntu/+source/libpam-mount/+bug/1908638

Evan Linde
Research Cyberinfrastructure Analyst
Oklahoma State University
High Performance Computing Center
405-744-1455
http://hpcc.okstate.edu/

We believe that the bug you reported is fixed in the latest version of
libpam-mount, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 980117@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Jochen Sprickerhof <jspricke@debian.org> (supplier of updated libpam-mount package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Thu, 07 Jul 2022 09:10:56 +0200
Source: libpam-mount
Architecture: source
Version: 2.19-1
Distribution: unstable
Urgency: medium
Maintainer: Jochen Sprickerhof <jspricke@debian.org>
Changed-By: Jochen Sprickerhof <jspricke@debian.org>
Closes: 980117
Changes:
 libpam-mount (2.19-1) unstable; urgency=medium
 .
   * Update upstream signing key
   * New upstream version 2.19
   * Update d/copyright
   * news file was renamed
   * Rebase patch
   * Restrict source mount check to ignore NFS and crypt (Closes: #980117)
   * Bump policy version (no changes)
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 c2927591dc5a630d4b329abee2a6bfda6ce1fd2e 28792 libpam-mount_2.19-1.debian.tar.xz
 28dc9de69b596e868176cc8cb7ab28206ecb801d 6755 libpam-mount_2.19-1_source.buildinfo
Checksums-Sha256:
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Files:
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 c125ac855c40742e52a3acc26de07a5d 28792 admin optional libpam-mount_2.19-1.debian.tar.xz
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