Re: [fuse-devel] [RFC] fuse: Support posix ACLs

[Seth Forshee <seth.forshee@canonical.com>]

On Fri, Jul 01, 2016 at 12:33:40PM -0700, Nikolaus Rath wrote:
> On Jun 29 2016, ebiederm@xmission.com (Eric W. Biederman) wrote:
> > "Michael j Theall" <mtheall@us.ibm.com> writes:
> >
> >> Going by the patch I posted a couple of years ago:
> >> https://sourceforge.net/p/fuse/mailman/message/33033653/
> >>
> >> The only hole I see in your patch is that in setattr() you are not
> >> updating the cached acl if the ATTR_MODE is updated. The other major
> >> difference is that my version uses the get_acl/set_acl inode
> >> operations but you use that plus the xattr handlers. I'm not
> >> up-to-speed on the kernel so I'm not sure if you actually need to
> >> implement both.
> >
> > That makes an interesting question.  Is it desirable to keep
> > inode->i_mode in sync with the posix acls in fuse or should a filesystem
> > that supports posix acls worry about that?
> 
> A FUSE file system should be able to support ACLs without requiring the
> file system process to do more than support extended attributes. I
> believe this means that the kernel should keep i_mode and the ACLs in
> sync -- it would be a rather bug prone and redundant for each FUSE file
> system to implement its own parser for format in which the ACLs are
> stored in xattrs.

The most recent patch I posted keeps them in sync.

Thanks,
Seth