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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Mon, 17 Jul 2023 16:51:29 -0700
Message-ID: <CAADnVQK6J2TNNRMaZDkC7NNHO6uGs4MrUvocWW-TXsSNg_7s5g@mail.gmail.com>
Subject: Re: [PATCH v2 2/9] bpf/btf: tracing: Move finding func-proto API and
 getting func-param API to BTF
To:     Masami Hiramatsu <mhiramat@kernel.org>
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>
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On Mon, Jul 17, 2023 at 4:46=E2=80=AFPM Masami Hiramatsu <mhiramat@kernel.o=
rg> wrote:
>
> >
> > > + * Return NULL if not found, or return -EINVAL if parameter is inval=
id.
> > > + */
> > > +const struct btf_type *btf_find_func_proto(struct btf *btf, const ch=
ar *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.