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From:   Junio C Hamano <gitster@pobox.com>
To:     Phillip Wood <phillip.wood123@gmail.com>
Cc:     Taylor Blau <me@ttaylorr.com>, git@vger.kernel.org,
        Derrick Stolee <derrickstolee@github.com>,
        Jeff King <peff@peff.net>,
        Johannes Schindelin <Johannes.Schindelin@gmx.de>,
        Victoria Dye <vdye@github.com>
Subject: Re: [PATCH 02/20] packfile.c: prevent overflow in `load_idx()`
References: <cover.1689205042.git.me@ttaylorr.com>
        <d6902cd9e7f7f2a6b8044c8fb782a28c23e15600.1689205042.git.me@ttaylorr.com>
        <5d2cf09f-34c7-9a88-bab2-8bf348dd13bb@gmail.com>
Date:   Thu, 13 Jul 2023 09:14:05 -0700
In-Reply-To: <5d2cf09f-34c7-9a88-bab2-8bf348dd13bb@gmail.com> (Phillip Wood's
        message of "Thu, 13 Jul 2023 09:21:55 +0100")
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Phillip Wood <phillip.wood123@gmail.com> writes:

>> -		p->crc_offset = 8 + 4 * 256 + nr * hashsz;
>> +		p->crc_offset = st_add(8 + 4 * 256, st_mult(nr, hashsz));
>
> p->crc_offset is a uint32_t so we're still prone to truncation here

Good eyes.  Thanks.