Subject: Re: [PATCH bpf-next 00/10] bpf_link observability APIs

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Fri, 24 Apr 2020 13:40:16 +0200

Andrii Nakryiko <[email-masked]> writes:

> This patch series adds various observability APIs to bpf_link:
>   - each bpf_link now gets ID, similar to bpf_map and bpf_prog, by which
>     user-space can iterate over all existing bpf_links and create limited FD
>     from ID;
>   - allows to get extra object information with bpf_link general and
>     type-specific information;
>   - implements `bpf link show` command which lists all active bpf_links in the
>     system;
>   - implements `bpf link pin` allowing to pin bpf_link by ID or from other
>     pinned path.
>
> rfc->v1:
>   - dropped read-only bpf_links (Alexei);

Just to make sure I understand this right: With this change, the
GET_FD_BY_ID operation will always return a r/w bpf_link fd that can
subsequently be used to detach the link? And you're doing the 'access
limiting' by just requiring CAP_SYS_ADMIN for the whole thing. Right? :)

-Toke