Cannot umount ntfs-36 with umount command

[dabicho]

I think I have found what is happening.

The entry in fstab for this device (recognized by label) has the
"user" option. It is mounted using ntfs-3g with fuser, so the binary
is suid to be able to mount as ordinary user.
After mounting, the mount point has the same owner as the user who
mounted the filesystem, but said user is not allowed to umount the
filesystem.

What I did is change the "user"option into "users" (which I would
rather not have to).
My guess is the problem resides in the suid bit for ntfs-3g somehow,
but I could not find any documented behaviour.

Thank you.

On Tue, Mar 17, 2015 at 9:07 PM, dabicho <tsukebumi at gmail.com> wrote:
> Hello
>
> I am having a problem with umountint an ntfs-3g mounted filesystem
>
> This is the output I get from the commands
>
> [siirfe at 010121 ~]$ mount /mnt/mac/
> [siirfe at 010121 ~]$ mount |grep mac
> /dev/sdb1 on /mnt/mac type fuseblk
> (rw,nosuid,nodev,noexec,relatime,user_id=1002,group_id=1002,allow_other,blksize=4096)
> [siirfe at 010121 ~]$ umount /mnt/mac/
> umount: /mnt/mac: umount failed: Operation not permitted
> [siirfe at 010121 ~]$ grep mac /etc/fstab
> /dev/disk/by-label/SIIRFE_MAC     /mnt/mac   auto
> iocharset=utf8,noauto,user 0 0
> [siirfe at 010121 ~]$ grep mac /etc/mtab
> /dev/sdb1 /mnt/mac fuseblk
> rw,nosuid,nodev,noexec,relatime,user_id=1002,group_id=1002,allow_other,blksize=4096
> 0 0
> [siirfe at 010121 ~]$ fusermount -u /mnt/mac/
>
>
> fusermount -u works correctly
>
> What is going on here? what am I missing?
> I don't use gnome nor kde
>
> I appreciate any input. Thank you