Re: Reviewing freeze map code

On Sun, May 29, 2016 at 1:44 AM, Noah Misch <noah(at)leadboat(dot)com> wrote:
> On Fri, May 06, 2016 at 04:42:48PM -0400, Robert Haas wrote:
>> On Thu, May 5, 2016 at 2:20 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>> > On 2016-05-02 14:48:18 -0700, Andres Freund wrote:
>> > + char new_vmbuf[BLCKSZ];
>> > + char *new_cur = new_vmbuf;
>> > + bool empty = true;
>> > + bool old_lastpart;
>> > +
>> > + /* Copy page header in advance */
>> > + memcpy(new_vmbuf, &pageheader, SizeOfPageHeaderData);
>> >
>> > Shouldn't we zero out new_vmbuf? Afaics we're not necessarily zeroing it
>> > with old_lastpart && !empty, right?
>>
>> Oh, dear. That seems like a possible data corruption bug. Maybe we'd
>> better fix that right away (although I don't actually have time before
>> the wrap).
>
> [This is a generic notification.]
>
> The above-described topic is currently a PostgreSQL 9.6 open item. Robert,
> since you committed the patch believed to have created it, you own this open
> item. If some other commit is more relevant or if this does not belong as a
> 9.6 open item, please let us know. Otherwise, please observe the policy on
> open item ownership[1] and send a status update within 72 hours of this
> message. Include a date for your subsequent status update. Testers may
> discover new open items at any time, and I want to plan to get them all fixed
> well in advance of shipping 9.6rc1. Consequently, I will appreciate your
> efforts toward speedy resolution. Thanks.

I am going to try to find time to look at this later this week, but
realistically it's going to be a little bit difficult to find that
time. I was away over Memorial Day weekend and was in meetings most
of today. I have a huge pile of email to catch up on. I will send
another status update no later than Friday. If Andres or anyone else
wants to jump in and fix this up meanwhile, that would be great.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company