Re: REFERENCES privilege should not be symmetric (was Re: [GENERAL] Postgres Permissions Article)

On Fri, Mar 31, 2017 at 7:40 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> Robert Haas <robertmhaas@gmail.com> writes:
> > On Fri, Mar 31, 2017 at 11:29 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> The argument for not back-patching a bug fix usually boils down to
> >> fear of breaking existing applications, but it's hard to see how
> >> removal of a permission check could break a working application ---
> >> especially when the permission check is as hard to trigger as this one.
> >> How many table owners ever revoke their own REFERENCES permission?
>
> > Sure, but that argument cuts both ways.  If nobody ever does that, who
> > will be helped by back-patching this?
> > I certainly agree that back-patching this change is pretty low risk.
> > I just don't think it has any real benefits.
>
> I think the benefit is reduction of user confusion.  Admittedly, since
> Paul is the first person I can remember ever having complained about it,
> maybe nobody else is confused.
>

I think we also need to be extra careful about changing *security related*
behavior in back branches, even more so than other behavior. In this case I
think it's quite unlikely that it would hit somebody, but the risk is
there. And people generally auto-upgrade to the latest minor releases,
whereas they at least in theory read the top of the release notes when
doing a major upgrade (ok, most people probably don't, but at least some
do).

-- 
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/