Borg: Can mount, but not umount

[rugk]

v1.0.9

STR (working as a non-root user by default):

1. mkdir mnt
2. setting repo/passphrase
3. shell $ borg mount :: ./mnt fuse: failed to exec fusermount: No such file or directory
4. Retried with sudo borg mount :: ./mnt works. (borg mount :: ./mnt 4,81s user 0,75s system 27% cpu 19,883 total) on a btrfs filesystem BTW. (Also set repo etc. again, so it works.)
5. browse in it
   (interestingly for non-root users no username/password were shown and they could not access it)
6. Unmounting fails:

borg umount ./mnt
Local Exception.
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/borg/archiver.py", line 2052, in main
    exit_code = archiver.run(args)
  File "/usr/lib/python3/dist-packages/borg/archiver.py", line 1997, in run
    return func(args)
  File "/usr/lib/python3/dist-packages/borg/archiver.py", line 564, in do_umount
    return umount(args.mountpoint)
  File "borg/platform_linux.pyx", line 148, in borg.platform_linux.umount (borg/platform_linux.c:4217)
  File "/usr/lib/python3.5/subprocess.py", line 247, in call
    with Popen(*popenargs, **kwargs) as p:
  File "/usr/lib/python3.5/subprocess.py", line 676, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.5/subprocess.py", line 1282, in _execute_child
    raise child_exception_type(errno_num, err_msg)
FileNotFoundError: [Errno 2] No such file or directory: 'fusermount'

Platform: XXXXXXX #2 SMP Sat May 6 19:26:50 UTC 2017 armv7l 
Linux: debian 9.0 
Borg: 1.0.9  Python: CPython 3.5.3
PID: 9277  CWD XXXXX
sys.argv: ['/usr/bin/borg', 'umount', './mnt']
SSH_ORIGINAL_COMMAND: None

With umount ./mnt I could finally unmount the repo anyway…

[ThomasWaldmann]

Why don't you have fusermount?

fusermount -u is the usual way to unmount a FUSE mount as a user on linux.

according to your error messages, it seems to be also used by mount somehow (although borg does not directly call it for that).

[rugk]

It's not there, but somehow borg managed to mount the archive anyway…

$ which fusermount
fusermount not found
$ ls -la /usr/bin/*mount* 
-rwxr-xr-x 1 root root 1275 Jun 10  2016 /usr/bin/cgroupfs-mount
-rwxr-xr-x 1 root root  620 Jun 10  2016 /usr/bin/cgroupfs-umount
$ ls -la /bin/*mount* 
-rwsr-xr-x 1 root root 30832 Mär 22 10:43 /bin/mount
-rwxr-xr-x 1 root root  9952 Mär 22 10:43 /bin/mountpoint
-rwsr-xr-x 1 root root 22492 Mär 22 10:43 /bin/umount

fusermount -u is the usual way to unmount a FUSE mount as a user on linux.

Upps, but "umount" worked anyway… :laughing:

Debian 9 here, Bananian here. fusermount does not seem to be included in Bananian. :smile:
And the borg Debian package also does not seem to have it set as a dependency. :smile:

[ThomasWaldmann]

In Ubuntu, it is in the fuse package and gets installed to /bin/fusermount.

[rugk]

Maybe, but as I said, it's not there, here. I think my commands above prove this.

[ThomasWaldmann]

OK, file a bug to bananian or whatever, this is out of scope of borg.

[rugk]

But it is inside the scope of borg, why it could actually mount an archive without fusermount…
That's a kinda strange bug, as – if there would not be any other tool for unmounting – the user would have been trapped here.

[ThomasWaldmann]

being able to do mount as root is no surprise, the point of fusermount is not needing root.

but if you don't have fusermount installed (for whatever reason outside of borg project that is), it won't work as user.

[ThomasWaldmann]

hmm, the only thing that might be todo for borg umount is to check whether it runs as root and whether calling fusermount -u failed and then just try umount.

[rugk]

Ah, yeah, now I understand. :+1: