Re: BUG #15540: Use after release in ExecuteTruncateGuts

On 2018-Dec-07, Tom Lane wrote:

> =?utf-8?q?PG_Bug_reporting_form?= <noreply@postgresql.org> writes:
> > The function ExecuteTruncateGuts drops the reference to rel via
> > relation_close when toast_relid is valid. However, after that, rel is passed
> > to pgstat_count_truncate. This may result in a use-after-release bug.
> 
> ... and, even more to the point, the truncation stats count is incorrectly
> applied to the toast table not its parent.

Whoops!  Thanks for fixing.  You're right, we quite likely didn't
specifically test the case of there being a toast table.  Amazing that
it took so long to find it.

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