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Date:   Tue, 18 Jul 2023 10:03:45 +0900
From:   Masami Hiramatsu (Google) <mhiramat@kernel.org>
To:     Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        linux-trace-kernel@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        bpf <bpf@vger.kernel.org>, Sven Schnelle <svens@linux.ibm.com>,
        Alexei Starovoitov <ast@kernel.org>
Subject: Re: [PATCH v2 2/9] bpf/btf: tracing: Move finding func-proto API
 and getting func-param API to BTF
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On Mon, 17 Jul 2023 16:51:29 -0700
Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:

> On Mon, Jul 17, 2023 at 4:46 PM Masami Hiramatsu <mhiramat@kernel.org> wrote:
> >
> > >
> > > > + * Return NULL if not found, or return -EINVAL if parameter is invalid.
> > > > + */
> > > > +const struct btf_type *btf_find_func_proto(struct btf *btf, const char *func_name)
> > > > +{
> > > > +   const struct btf_type *t;
> > > > +   s32 id;
> > > > +
> > > > +   if (!btf || !func_name)
> > > > +           return ERR_PTR(-EINVAL);
> 
> Please remove these checks.
> We don't do defensive programming in the BPF subsystem.
> Don't pass NULL pointers to such functions.

OK, we will trust API user to pass a non-NULL parameters.

Thank you!

-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>