Date: Tue, 24 Jan 2023 17:25:38 +0900 (JST)
Message-Id: <20230124.172538.809130207355878809.horikyota.ntt@gmail.com>
To: melanieplageman@gmail.com
Cc: vignesh21@gmail.com, andres@anarazel.de, pryzby@telsasoft.com,
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 pgsql-hackers@postgresql.org, thomas.munro@gmail.com, m.sakrejda@gmail.com
Subject: Re: pg_stat_bgwriter.buffers_backend is pretty meaningless (and
 more?)
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
In-Reply-To: <20230124.172203.448918351330829200.horikyota.ntt@gmail.com>
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At Tue, 24 Jan 2023 17:22:03 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in 
> +pgstat_count_io_op(IOObject io_object, IOContext io_context, IOOp io_op)
> +{
> +	Assert(io_object < IOOBJECT_NUM_TYPES);
> +	Assert(io_context < IOCONTEXT_NUM_TYPES);
> +	Assert(io_op < IOOP_NUM_TYPES);
> +	Assert(pgstat_tracks_io_op(MyBackendType, io_object, io_context, io_op));
> 
> Is there any reason for not checking the value ranges at the
> bottom-most functions?  They can lead to out-of-bounds access so I

To make sure, the "They" means "out-of-range io_object/context/op
values"..

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center