Re: [PATCH][BUG FIX] Unsafe access pointers. - Mailing list pgsql-hackers

On 2019-Nov-15, Ranier Vilela wrote:

> Hi,
> Last time, I promise.
> 
> It's probably not happening, but it can happen, I think.

This patch assumes that anything can happen after elog(ERROR).  That's
wrong -- under ERROR or higher, elog() (as well as ereport) never
returns to the caller.  If this was possible, there would be thousands
of places that would need to be patched, all over the server code.  But
it's not.

>      /* Fetch opclass information */
>      classtup = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclassoid));
> -    if (!HeapTupleIsValid(classtup))
> +    if (!HeapTupleIsValid(classtup)) {
>          elog(ERROR, "cache lookup failed for operator class %u", opclassoid);
> +        return false;
> +    }


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