Thread

Re: Add errdetail() with PID and UID about source of termination signal

Andrew Dunstan <andrew@dunslane.net> — 2026-05-01T17:26:51Z

On Thu, Apr 23, 2026 at 6:20 AM Jakub Wartak <jakub.wartak@enterprisedb.com>
wrote:

> On Thu, Apr 23, 2026 at 11:28 AM Chao Li <li.evan.chao@gmail.com> wrote:
>
> Hi Chao
>
> >
> > I just got a suspicion about this feature. The repro is very simple: let
> a normal user connect to the server, then run pg_ctl stop, and from psql
> you get:
> > ```
> > evantest=> select 1;
> > FATAL:  terminating connection due to administrator command
> > DETAIL:  Signal sent by PID 17523, UID 501.
> > server closed the connection unexpectedly
> >         This probably means the server terminated abnormally
> >         before or while processing the request.
> > The connection to the server was lost. Attempting reset: Failed.
> > The connection to the server was lost. Attempting reset: Failed.
> > !?>
> > ```
> >
> > Do we really need to show the DETAIL message with the PID and UID to an
> ordinary client? Is there any concern about leaking the UID in a shared
> production deployment?
> >
> > If this is confirmed an issue, I made a simple fix by using
> errdetail_log() to only emit the detail message to server log. Please the
> attached diff file.
>
> +1, I think logging just to file is even better than sending it to the
> client(s) and it also solves the potential security risk (if any).
>
>
> I agree, I have pushed the patch.

cheers

andrew