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From:   Brendan Jackman <jackmanb@google.com>
Date:   Thu, 29 Apr 2021 10:46:06 +0200
Message-ID: <CA+i-1C3YJQt60FBaOg3pHD+BG6kuUK1Z8RiZ87O9+WSr1Ynbyg@mail.gmail.com>
Subject: Re: [PATCH bpf-next] libbpf: Fix signed overflow in ringbuf_process_ring
To:     Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc:     KP Singh <kpsingh@kernel.org>, bpf <bpf@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        open list <linux-kernel@vger.kernel.org>
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On Wed, 28 Apr 2021 at 20:13, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
...
>
> Yep, let's cap. But to not penalize a hot loop with extra checks.
> Let's use int64_t internally for counting and only cap it before the
> return.

Cool, sounds good. Patch incoming but I'm on interrupts duty this week
so might not be today/tomorrow.