Re: Avoid memory leaks during base backups

On Thu, Oct 20, 2022 at 11:17 PM Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> wrote:
>
> On 2022-Oct-20, Bharath Rupireddy wrote:
>
> > I think elsewhere in the code we reset dangling pointers either ways -
> > before or after deleting/resetting memory context. But placing them
> > before would give us extra safety in case memory context
> > deletion/reset fails. Not sure what's the best way. However, I'm
> > nullifying the dangling pointers after deleting/resetting memory
> > context.
>
> I agree that's a good idea, and the patch looks good to me, but I don't
> think asserting that they are null afterwards is useful.

+1. Removed those assertions. Please see the attached v9 patch.

On Fri, Oct 21, 2022 at 12:21 AM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>
> On Thu, Oct 20, 2022 at 1:35 PM Bharath Rupireddy
> <bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote:
> > I think elsewhere in the code we reset dangling pointers either ways -
> > before or after deleting/resetting memory context. But placing them
> > before would give us extra safety in case memory context
> > deletion/reset fails. Not sure what's the best way.
>
> I think it's OK to assume that deallocating memory will always
> succeed, so it doesn't matter whether you do it just before or just
> after that. But it's not OK to assume that *allocating* memory will
> always succeed.

Right.

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com