Re: PL/Python: Fix return in the middle of PG_TRY() block. - Mailing list pgsql-hackers

On Thu, Jan 12, 2023 at 11:19:29PM +0800, Xing Guo wrote:
> I was running static analyser against PostgreSQL and found there're 2
> return statements in PL/Python module which is not safe. Patch is
> attached.

Is the problem that PG_exception_stack and error_context_stack aren't
properly reset?

> @@ -690,12 +690,12 @@ PLy_trigger_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc, HeapTuple *r
>      PyObject   *volatile pltdata = NULL;
>      char       *stroid;
>  
> +    pltdata = PyDict_New();
> +    if (!pltdata)
> +        return NULL;
> +
>      PG_TRY();
>      {
> -        pltdata = PyDict_New();
> -        if (!pltdata)
> -            return NULL;
> -
>          pltname = PLyUnicode_FromString(tdata->tg_trigger->tgname);
>          PyDict_SetItemString(pltdata, "name", pltname);
>          Py_DECREF(pltname);

There's another "return" later on in this PG_TRY block.  I wonder if it's
possible to detect this sort of thing at compile time.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com