Re: BUG #16330: psql accesses null pointer in connect.c:do_connect

On 2020-Mar-30, Tom Lane wrote:

> Michael Paquier <michael(at)paquier(dot)xyz> writes:
> > On Mon, Mar 30, 2020 at 02:20:48AM +0000, PG Bug reporting form wrote:
> >> If the connection to postmaster is closed, then trying to re-connect to
> >> another one leads to SIGSEGV.
>
> > A fix like the attached should be sufficient as if we know that
> > PQhost() is NULL for the old connection we cannot use the old
> > hostaddr. Alvaro, what do you think?
>
> It looks to me like there's a similar hazard a bit further down
> (line 3029):
>
> appendConnStrVal(&connstr, PQdb(o_conn));
>
> I wonder if we should force reuse_previous to false if there's
> no o_conn, rather than fixing this stuff piecemeal.

That was my impression too.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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