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From:   KP Singh <kpsingh@chromium.org>
Date:   Tue, 11 Feb 2020 13:44:48 +0100
To:     Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc:     KP Singh <kpsingh@chromium.org>, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org, linux-security-module@vger.kernel.org,
        Brendan Jackman <jackmanb@google.com>,
        Florent Revest <revest@google.com>,
        Thomas Garnier <thgarnie@google.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
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        Kees Cook <keescook@chromium.org>,
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Subject: Re: [PATCH bpf-next v3 03/10] bpf: lsm: Introduce types for eBPF
 based LSM
Message-ID: <20200211124448.GB96694@google.com>
References: <20200123152440.28956-1-kpsingh@chromium.org>
 <20200123152440.28956-4-kpsingh@chromium.org>
 <20200210235811.pbzvlok6rin7lctd@ast-mbp>
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On 10-Feb 15:58, Alexei Starovoitov wrote:
> On Thu, Jan 23, 2020 at 07:24:33AM -0800, KP Singh wrote:
> > +
> > +static const struct bpf_func_proto *get_bpf_func_proto(
> > +	enum bpf_func_id func_id, const struct bpf_prog *prog)
> > +{
> > +	switch (func_id) {
> > +	case BPF_FUNC_map_lookup_elem:
> > +		return &bpf_map_lookup_elem_proto;
> > +	case BPF_FUNC_get_current_pid_tgid:
> > +		return &bpf_get_current_pid_tgid_proto;
> > +	default:
> > +		return NULL;
> > +	}
> > +}
> > +
> > +const struct bpf_verifier_ops lsm_verifier_ops = {
> > +	.get_func_proto = get_bpf_func_proto,
> > +};
> 
> Why artificially limit it like this?
> It will cause a lot of churn in the future. Like allowing map update and
> delete, in addition to lookup, will be an obvious next step.
> I think allowing tracing_func_proto() from the start is cleaner.

Sure, I will replace it to use tracing_func_proto in the next
revision.

- KP