On Wed 2017-08-23 (10:16), Dmitrii Tcvetkov wrote:

quoted

quoted

Also in https://btrfs.wiki.kernel.org/index.php/Mount_options
"user_subvol_rm_allowed (...) Use with caution."

Why? What is the problem?  

Because with the mount option any user can delete any subvolume,
including root one (subvol_id=5)

Apologies, it works somewhat different:
filesystem doesn't allow to delete subvolume with id 5 and POSIX access
is checked before deleting subvolume with user_subvol_rm_allowed mount
option.

I have tested it already :-)

So, still: What is the problem with user_subvol_rm_allowed?

-- 
Ullrich Horlacher              Server und Virtualisierung
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