Re: [PATCH bpf-next 4/8] bpf: Teach verifier that certain helpers accept NULL pointer.

[Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx>]

On Tue, Apr 4, 2023 at 5:10 PM Martin KaFai Lau <martin.lau@xxxxxxxxx> wrote:
>
> On 4/3/23 9:50 PM, Alexei Starovoitov wrote:
> > diff --git a/net/core/filter.c b/net/core/filter.c
> > index 1f2abf0f60e6..727c5269867d 100644
> > --- a/net/core/filter.c
> > +++ b/net/core/filter.c
> > @@ -4998,7 +4998,7 @@ const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
> >       .func           = bpf_get_socket_ptr_cookie,
> >       .gpl_only       = false,
> >       .ret_type       = RET_INTEGER,
> > -     .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
> > +     .arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON | PTR_MAYBE_NULL,
>
> I think the bpf_skc_to_* helpers (eg. bpf_skc_to_tcp_sock) also need similar
> change. They are available to tracing also. It can be a follow-up. The patch set
> lgtm.

Ok. I'll take a look.