Bufmgr possible overflow - Mailing list pgsql-hackers

From Ranier Vilela
Subject Bufmgr possible overflow
Date
Msg-id CAEudQAr_oWHpZk4uumZijYS362gp4KHAah-yUe08CQY4a4SsOQ@mail.gmail.com
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Responses Re: Bufmgr possible overflow  (Kyotaro Horiguchi <horikyota.ntt@gmail.com>)
List pgsql-hackers
Hi,

IMO I think that commit 31966b1 has an oversight.

All the logic of the changes are based on the "extend_by" variable, which is a uint32, but in some places it is using "int", which can lead to an overflow at some point.

I also take the opportunity to correct another oversight, regarding the commit dad50f6,
for possible duplicate assignment.
GetLocalBufferDescriptor was called twice.

Taking advantage of this, I promoted a scope reduction for some variables, which I thought was opportune.

Patch attached.

regards,
Ranier Vilela
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