[Pkg-zfsonlinux-devel] Bug#1028613: libpam-zfs: zfs_umount failed on closing ssh session

[Andreas Mahling]

Package: libpam-zfs
Version: 2.1.7-1~bpo11+1
Severity: normal
X-Debbugs-Cc: andreas.mahling at googlemail.com

Dear Maintainer,

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I have configured a user 'test1' with a zfs encrypted homedir 'tank/home/test1'

The only thing I'd changed on stock pam configuration was adding option homes=tank/home

When I start a session for test1 via terminal login, su - test1, ssh test1 at localhost or graphical login, the homedir is sucessfully mounted and decrypted with the password of test1

When I terminate the terminal or su - session, test1 homedir is umnounted and encryption key is unloaded as expected.

But when I terminate the ssh session an error is thrown:
Jan 13 16:31:01 rpi-400 sshd[2207]: pam_zfs_key(sshd:session): zfs_unmount failed with: -1

test1 homedir is still mounted and readable. 
Same problem occurs when terminating a graphical desktop session.

Excpected behaviour: encrypted zfs homedir should be unmounted if there is no sesssion active for test1

-- System Information:
Debian Release: 11.6
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: arm64 (aarch64)
Foreign Architectures: armhf

Kernel: Linux 5.15.84-v8+ (SMP w/4 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_CRAP, TAINT_OOT_MODULE
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to de_DE.UTF-8), LANGUAGE=de_DE.UTF-8
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages libpam-zfs depends on:
ii  libc6            2.31-13+rpt2+rpi1+deb11u5
ii  libnvpair3linux  2.1.7-1~bpo11+1
ii  libpam-runtime   1.4.0-9+deb11u1+rpt2
ii  libpam0g         1.4.0-9+deb11u1+rpt2
ii  libssl1.1        1.1.1n-0+deb11u3+rpt1
ii  libzfs4linux     2.1.7-1~bpo11+1

libpam-zfs recommends no packages.

libpam-zfs suggests no packages.

-- no debconf information