Re: Reviewing freeze map code - Mailing list pgsql-hackers

From Noah Misch
Subject Re: Reviewing freeze map code
Date
Msg-id 20160529054426.GF496776@tornado.leadboat.com
Whole thread Raw
In response to Re: Reviewing freeze map code  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: Reviewing freeze map code
Re: Reviewing freeze map code
List pgsql-hackers
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@anarazel.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.

[1] http://www.postgresql.org/message-id/20160527025039.GA447393@tornado.leadboat.com



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