encfs on top of eCryptfs triggers new flush-ecryptfs- process at relog

[Thaddaeus Tintenfisch]

Unmounting an encfs encrypted directory does not work properly, because it somehow causes a new flush-ecryptfs- process to spawn at logout/login. This process blocks the corresponding partition from being cleanly unmounted at shutdown (-> orphaned inodes).

$ encfs ~/.Cloud ~/Cloud
$ fusermount -u ~/Cloud

$ uname -a
Linux acer-tm8471 3.9.0-030900rc8-generic #201304211835 SMP Sun Apr 21 22:35:53 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

$ apt-cache policy encfs
encfs:
  Installed: 1.7.4-2.4build1
  Candidate: 1.7.4-2.4build1
  Version table:
 *** 1.7.4-2.4build1 0
        500 http://de.archive.ubuntu.com/ubuntu/ raring/universe amd64 Packages
        100 /var/lib/dpkg/status

[Tyler Hicks (tyhicks)]

eCryptfs and encfs are two very different things. There's no way that encfs is triggering a flush-ecryptfs- process.

Do you have your home directory mounted with eCryptfs? To check, log in and then open the /proc/mounts file to see if /home/$USER is mounted as an eCryptfs mount.

[Thaddaeus Tintenfisch (thad-fisch-deactivatedaccount)]

Yes, the /home partition is encrytped as well (ecryptfs).

The problem is, that an additional flush-ecryptfs- process appears every time I mount/unmount my encfs encrypted directory (/home/thad/.Cloud) and relog the user. It does only happen while working with encfs and there are no errors or whatsoever while mounting/unmounting. However, once I initiate a system shutdown, the /home partition can't be unmounted cleanly, because it is still busy.

[Tyler Hicks (tyhicks)]

Ok, so you have encfs mounted on top of eCryptfs. That isn't an environment that I test as the eCryptfs maintainer (I only test eCryptfs mounted on top of a variety of filesystems), so I'm not immediately sure what is happening.

Thanks for clarifying your setup.

[Thaddaeus Tintenfisch (thad-fisch-deactivatedaccount)]

Identical problem on Ubuntu Forums: http://ubuntuforums.org/showthread.php?t=2109303

Tyler, were you able to reproduce this bug? Why would an additional flush-ecryptfs- process appear after every relog?

[Thaddaeus Tintenfisch (thad-fisch-deactivatedaccount)]

I can't reproduce this issue anymore after installing the latest Kernel 3.9.2.

$ uname -a
Linux acer-tm8471 3.9.2-030902-generic #201305111035 SMP Sat May 11 14:36:04 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux