Re: role self-revocation

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> Notwithstanding the lack of agreement on that point, I believe that
> what we should do for v15 is remove the session user
> self-administration exception. We have pretty much established that it
> was originally introduced in error.

Agreed.

> However, it might. And if it does, I think it would be best if
> removing that exception were the *only* change in this area made by
> that release.

Good idea, especially since it's getting to be too late to consider
anything more invasive anyway.

> So I propose to commit something like what I posted here:
> http://postgr.es/m/CA+TgmobgeK0JraOwQVPqhSXcfBdFitXSomoebHMMMhmJ4gLonw@mail.gmail.com

+1, although the comments might need some more work. In particular,
I'm not sure that this bit is well stated:

+ * A role cannot have WITH ADMIN OPTION on itself, because that would
+ * imply a membership loop.

We already do consider a role to be a member of itself:

regression=# create role r;
CREATE ROLE
regression=# grant r to r;
ERROR: role "r" is a member of role "r"
regression=# grant r to r with admin option;
ERROR: role "r" is a member of role "r"

It might be better to just say "By policy, a role cannot have WITH ADMIN
OPTION on itself". But if you want to write a defense of that policy,
this isn't a very good one.

regards, tom lane