vfs.usermount allows users to do arbitrary unmounts

[Yuri Pankov]

Yuri Pankov wrote:
> Hi,
> 
> Going through https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=232021, 
> I noticed that unmount(2) will not fail with EPERM as expected on mounts 
> that don't belong to the user, and which were not mounted by that user, 
> e.g.:
> 
> # zfs create data/test
> # ls -ld /data/test
> drwxr-xr-x  2 root  wheel  2 Oct  7 21:55 /data/test
> $ umount /data/test; echo $?
> 0
> 
> Even if vfs.usermount isn't great from security perspective, is this 
> expected?

Nevermind me, looks like I got it all confused with using `zfs allow`.