Horton

Re: Range Types - typo + NULL string constructor

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

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From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
To: Jeff Davis <pgsql@j-davis.com>
Cc: Alexander Korotkov <aekorotkov@gmail.com>, pgsql-hackers@postgresql.org
Date: 2011-10-26T06:53:46Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Replace the "New Linear" GiST split algorithm for boxes and points with a

On 25.10.2011 19:37, Jeff Davis wrote:
> On Mon, 2011-10-24 at 13:15 +0300, Heikki Linnakangas wrote:
>> Hmm, I don't think that's safe. After Oid wraparound, a range type oid
>> might get reused for some other range type, and the cache would return
>> stale values. Extremely unlikely to happen by accident, but could be
>> exploited by an attacker.
>
> Any ideas on how to remedy that? I don't have another plan for making it
> perform well. Plugging it into the cache invalidation mechanism seems
> like overkill, but I suppose that would solve the problem.

I think we should look at the array-functions for precedent. array_in et 
al cache the information in fn_extra, so that when it's called 
repeatedly in one statement for the same type, the information is only 
looked up once. That's good enough, it covers repeated execution in a 
single query, as well as COPY and comparison calls from index searches, 
for example.

> Aren't there a few other cases like this floating around the code?

Not that I know of. That said, I wouldn't be too surprised if there was.

> I know the single-xid cache is potentially vulnerable to xid wraparound
> for the same reason.

True.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com