Leaves disconnected devices' filesystems mounted / doesn't unmount

[Shahar Or]

Dear Ones,

usbmount just leaves partitions mounted... It never unmounts them when devices are disconnected!

So I have /media/usb0 mounted still after I disconnect the device!
And when I reconnect it - usbmount mounts it again at /media/usb1.

dmesg shows a log entry about the disconnecting of the device so there's apparently no reason to not consider it unmounted anymore. Perhaps this is not usbmount's fault?

Could anyone please look at the attached stuff and tell me what might be going on? I don't have regular physical access to this server.

Thanks and Blessings,
Shahar

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: usbmount 0.0.21ubuntu0.1
ProcVersionSignature: Ubuntu 3.0.0-15.26-generic-pae 3.0.13
Uname: Linux 3.0.0-15-generic-pae i686
ApportVersion: 1.23-0ubuntu4
Architecture: i386
Date: Thu Feb 23 00:49:59 2012
EcryptfsInUse: Yes
PackageArchitecture: all
SourcePackage: usbmount
UpgradeStatus: Upgraded to oneiric on 2011-10-19 (126 days ago)
mtime.conffile..etc.usbmount.usbmount.conf: 2012-02-10T21:41:36.796170

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Sasa Friedrich (frido77)]

I see this bug was reported on Ubuntu 11.10 and status is still confirmed.

I have exactly the same problem on Ubuntu 20.04, but only with VFAT partition type. EXFAT and NTFS are unmounted correctly.

I checked journal and when unplugging device I receive correct info:

systemd[1]: <email address hidden>: Succeeded

but file system is still shown as mounted on /media/usb0

After that I run:

umount /medit/usb0

and umount reports no error, exits with 0 and file system is not mounted anymore.

Now strange thing... I tried to force this "double unmount". I altered /usr/share/usbmount/usbmount and added another unmount command after first one. So in theory this should be the same as me running umount by hand after unplugging device.
But in this case systemd reports error:

systemd-udevd[1278522]: sdd1: Process '/usr/share/usbmount/usbmount remove' failed with exit code 32.

Exit code 32 is from umount and means 'not mounted'

BUT... if I check with mount, file system is still shown as mounted! If I (again) run same umount command by hand it exits with 0 and file system is unmounted.

I also tried to change umount -l (as originally in /usr/share/usbmount/usbmount) with force option umount -f. No difference.

And one more thing. On Ubuntu 16.04 there was no such problems. Unmount (after unplug) worked for all filesystems.

Any clue?

Thank you all for help!

BR