Re: emergency outage requiring database restart

On Wed, Oct 26, 2016 at 3:06 PM, Jim Nasby <Jim(dot)Nasby(at)bluetreble(dot)com> wrote:
> On 10/26/16 2:25 PM, Merlin Moncure wrote:
>>
>> I don't think that's the case. sqsh is a psql-like utility. it
>> writes to stdout and stderr only which is captured by plsh and sent.
>> In this context shexec only wraps rm -f 'file' where 'file' is a file
>> previously created with COPY in the same transaction.
>
> How do you know that? It could potentially be doing anything it wanted with
> file handles. Removing the exec might "solve" the problem here, assuming
> that the forked process doesn't still inherit all open FH's.
>
> In a nutshell, running arbitrary shell code (let alone arbitrary
> executables) in a pl that's running inside the Postgres backend sounds
> insanely risky to me.

Well, it is insantely risky, but the code in this context is not
arbitrary; it's only:
PERFORM shexec('rm -f ' || _OutputFile);

merlin