Re: [PATCH] libbpf: adjust OPTS_VALID logic, so that it can be used correctly

[Xin Liu]

On Wed, 14 Sep 2022 at 6:15:39 PM Hao Luo <haoluo@xxxxxxxxxx> wrote:
> Hi Xin,
>
> On Wed, Sep 14, 2022 at 5:35 AM Xin Liu <liuxin350@xxxxxxxxxx> wrote:
> >
> > We found that function btf_dump__dump_type_data can be called by the user
> > as an api, but in this function, the `opts` parameter may be used as a
> > null pointer, because OPTS_VALID can't properly prevent opts used as null
> > pointers during verification. Therefore, we fix this problem through this
> > modification.
> >
> > This modification has no impact on other places where OPTS_VALID has been
> > used.
>
> I think this is a bug of btf_dump__dump_type_data(), not OPTS_VALID.
> It seems allowing OPTS_VALID to accept NULL is the intended behavior.
>
> >
> [...]
> >

Thank you for your review.
You are right, OPTS_GET should be used to get data from opts and determine if
opts is NULL. Here I'll use OPTS_GET to fix the bug in the v2 version.