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From: Ashutosh Sharma <ashu.coek88@gmail.com>
Date: Fri, 5 Jun 2026 13:30:42 +0530
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Subject: Re: Fw: Re: heap_force_common in contrib/pg_surgery/heap_surgery.c
 has an off by one stack buffer overflow
To: Michael Paquier <michael@paquier.xyz>
Cc: surya poondla <suryapoondla4@gmail.com>,
	"violin0613@tju.edu.cn" <violin0613@tju.edu.cn>, pgsql-bugs@postgresql.org
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Hi Michael,

Thanks for the patch.

On Fri, Jun 5, 2026 at 12:27=E2=80=AFPM Michael Paquier <michael@paquier.xy=
z> wrote:
>
> On Fri, Jun 05, 2026 at 08:17:15AM +0900, Michael Paquier wrote:
> > At the end, the first pattern is an outlier, we don't need to worry
> > about performance in pg_surgery, and we're talking about three lines
> > of code in pg_surgery to change (two for include_this_tid, one for the
> > assertion).  With all that in mind, I'd just do a -1 conversion and
> > call it a day.  :)
>
> Which implies something like the simpler patch attached.

I have one small comment:

"+ Assert((offno - 1) < MaxHeapTuplesPerPage);"

I think this can be simplified to:

Assert(offno <=3D MaxHeapTuplesPerPage);

Since "offno" is already 1-based, there doesn't seem to be a need to
subtract 1 from it and adjust the comparison accordingly.

--
With Regards,
Ashutosh Sharma.