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Date: Wed, 9 Sep 2015 08:47:24 -0600
From: Tycho Andersen <tycho.andersen@canonical.com>
To: Kees Cook <keescook@chromium.org>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
        Linux API <linux-api@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>, Will Drewry <wad@chromium.org>,
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        Pavel Emelyanov <xemul@parallels.com>,
        "Serge E. Hallyn" <serge.hallyn@ubuntu.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        LKML <linux-kernel@vger.kernel.org>,
        Network Development <netdev@vger.kernel.org>
Subject: Re: [PATCH 5/6] seccomp: add a way to attach a filter via eBPF fd
Message-ID: <20150909144724.GZ26679@smitten>
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On Tue, Sep 08, 2015 at 05:07:03PM -0700, Kees Cook wrote:
>
> Yeah, bpf's union looks good. Let's add a "command" flag, though:
> 
> seccomp(SECCOMP_MODE_FILTER_EBPF, int cmd, union, size);
> 
> And this cmd could be ADD_FD or something?
> 
> How's that look?

I think we can drop the size (using the same strategy as bpf() and
checking for zeroes at the end), and keep the same signature for
seccomp(); so:

seccomp(SECCOMP_MODE_FILTER_EBPF, SECCOMP_ADD_BPF_FD, &union)

Yes, I'll use this in the next version.

Tycho