Re: lowering privs in SECURITY DEFINER function

Excerpts from Robert Haas's message of dom abr 10 13:37:46 -0300 2011:

> It's maybe worth noting here that what's being asked for is roughly
> what you get from UNIX's distinction between euid and ruid. Many
> programs that run setuid root perform a few operations that require
> root privileges up front, and then drop privs. To what degree that
> model applies in an SQL environment I'm not sure, but it might be
> worth looking at some of the parallels, as well as some of the ways
> that the UNIX mechanism has managed to cause all sorts of privilege
> escalation bugs over the years, to make sure we don't repeat those
> mistakes.

Thanks for mentioning that. It made me recall a couple of articles I
read some time ago,
http://lwn.net/Articles/416494/
and
http://www.cis.upenn.edu/~KeyKOS/ConfusedDeputy.html

--
Álvaro Herrera <alvherre(at)commandprompt(dot)com>
The PostgreSQL Company - Command Prompt, Inc.
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