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From:   Lorenz Bauer <lmb@cloudflare.com>
Date:   Wed, 13 Oct 2021 09:35:03 +0100
Message-ID: <CACAyw99ZfALrTRYKOTifWXCRFS9sUOhONbyEyWjTBdzFE4fpQQ@mail.gmail.com>
Subject: Re: [PATCH v2 4/4] bpf: export bpf_jit_current
To:     nicolas.dichtel@6wind.com
Cc:     Luke Nelson <luke.r.nels@gmail.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        kernel-team <kernel-team@cloudflare.com>,
        linux-doc@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>
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On Tue, 12 Oct 2021 at 17:29, Nicolas Dichtel <nicolas.dichtel@6wind.com> w=
rote:
>
> Le 12/10/2021 =C3=A0 15:59, Lorenz Bauer a =C3=A9crit :
> > Expose bpf_jit_current as a read only value via sysctl.
> >
> > Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
> > ---
>
> [snip]
>
> > +     {
> > +             .procname       =3D "bpf_jit_current",
> > +             .data           =3D &bpf_jit_current,
> > +             .maxlen         =3D sizeof(long),
> > +             .mode           =3D 0400,
> Why not 0444 ?

This mirrors what the other BPF related sysctls do, which only allow
access from root with CAP_SYS_ADMIN. I'd prefer 0444 as well, but
Daniel explicitly locked down these sysctls in
2e4a30983b0f9b19b59e38bbf7427d7fdd480d98.

Lorenz

--
Lorenz Bauer  |  Systems Engineer
6th Floor, County Hall/The Riverside Building, SE1 7PB, UK

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