Re: danger of stats_temp_directory = /dev/shm

On Thu, Apr 25, 2013 at 12:09 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
>> Jeff Janes escribió:
>>> With the stats file split patch 187492b6c2e8cafc5 introduced in 9.3dev, now
>>> after a crash the postmaster will try to delete all files in the directory
>>> stats_temp_directory. When that is just a subdirectory of PGDATA, this is
>>> fine. But it seems rather hostile when it is set to a shared directory,
>>> like the popular /dev/shm.
>
>>> Does this need to be fixed, or at least documented?
>
>> I think we need it fixed so that it only deletes the files matching a
>> well-known pattern.
>
> I think we need it fixed to reject any stats_temp_directory that is not
> postgres-owned with restrictive permissions. The problem here is not
> with what it deletes, it's with the insanely insecure configuration.

Only deleting files matching the relevant pattern might not be a bad
idea either, though.

--
Robert Haas
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