On Tue, 2008-10-28 at 12:18 -0400, David Schultz wrote:
> On Mon, Oct 27, 2008, Edward Tomasz Napierala wrote:
> > Let's say we have two directories, "A/" and "B/". We also have a
> > file, "A/F". To remove that file, we need write access to "A/".
> > To move that file to "B/", we need write access to both "A/" and
> > "B/". Now, assume we have a directory, "A/D". To remove that
> > directory, we need write access to "A/". To move that directory
> > to "B/", we need write access to "A/", "B/", _and "A/D"_.
> >
> > I'd like to remove the last check (requirement to have write access
> > to a directory we want to move somewhere else). Reason for this
> > is that it doesn't seem very logical, and many systems - including
> > SunOS, and our ZFS - behave differently. In other words, we have
> > different semantics on UFS and ZFS.

>
> No comment on other operating systems or standards, but I wanted
> to point out that there is some logic to FreeBSD's present behavior:
> When you move A/D, you must be able to write to D, because you are
> modifying D's ".." entry to point to B instead of A.
>
> >From a practical point of view, I think either behavior is fine,

> but we should consider whether any security-critical applications
> rely on the current behavior before changing it.


I was always mystified by the reason for this behavior until now... As
for my input, I think the change sounds fine (perhaps allowing revert to
old behavior via a sysctl).

--
Coleman Kane

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (FreeBSD)

iEUEABECAAYFAkkKCCIACgkQcMSxQcXat5fmygCXZqwgMnp9Nv JjhOt1sn/gXfGP
EQCfekwNaPCCSePdMfDxOOgpQr1b4WY=
=HMe3
-----END PGP SIGNATURE-----