Subject: Re: union mount directory permissions
To: Eric Haszlakiewicz <erh@nimenees.com>
From: David Laight <david@l8s.co.uk>
List: tech-kern
Date: 09/28/2004 08:09:27
>
> * policy: when creating the shadow directory in the
> * upper layer, create it owned by the user who did
> * the mount, group from parent directory, and mode
> * 777 modified by umask (ie mostly identical to the
> * mkdir syscall). (jsp, kb)
>
> uhm.. so, why? File permissions and ownership are copied. Shouldn't
> directories behave the same?
When I wrote a union fs, I created directories with the permissions
of their real parent.
I also deceided that the 'copy file into top layer' action was
unnecessary. Nothing we ran needed it.
I did try to use the feature of SVR4 VOP_OPEN() that allows it to return
a different vnode (use for clone open on special devices) but not all
of the kernel liked me doing that.
David
--
David Laight: david@l8s.co.uk