Re: FUSE merging?

Frank van Maarseveen
2005-07-01T15:21:26Z

On Fri, Jul 01, 2005 at 03:21:59PM +0200, Miklos Szeredi wrote:
>
> > To require an empty stub to mount FUSE upon makes the whole picture
> > cleaner: users are only able to extend the namespace _leaf_ nodes for
> > themselves and processes they can send signals to: setuid programs
> > which do not fully become root. The existing namespace [nodes] remains
> > unchanged for everyone.
>
> It's not as simple. A filesystem can be mounted many times (either
> with mount --bind, or just by mounting the same device on multiple
> mountpoints). In this case you can't ensure, that a mountpoint will
> remain a leaf node after being mounted on.

I have bind-mounted / on /net/blabla
I tried two experiments:

mounting something under / and looking for it under /net/blabla
mounting something under /net/blabla and looking for it under /

The experiment was done with bind mounts and by mounting a USB stick
(/dev/sdb1) and there was no auto propagation of mounts.

(2.6.12-rc6)

How can a leaf dir suddenly become non-leaf by a mount without an explicit
mount command?

--
Frank