[PATCH bpf-next v2 4/7] bpf: Attachment verification for BPF_MODIFY_RETURN

[Andrii Nakryiko]

On Tue, Mar 3, 2020 at 5:56 PM KP Singh <kpsingh at chromium.org> wrote:
>
> From: KP Singh <kpsingh at google.com>
>
> - Allow BPF_MODIFY_RETURN attachment only to functions that are:
>
>     * Whitelisted by for error injection i.e. by checking
>       within_error_injection_list. Similar disucssions happened for the
>       bpf_overrie_return helper.

2 typos: discussions and bpf_override_return ;)

>
>     * security hooks, this is expected to be cleaned up with the LSM
>       changes after the KRSI patches introduce the LSM_HOOK macro:
>
>         https://lore.kernel.org/bpf/20200220175250.10795-1-kpsingh@chromium.org/
>
> - The attachment is currently limited to functions that return an int.
>   This can be extended later other types (e.g. PTR).
>
> Signed-off-by: KP Singh <kpsingh at google.com>
> ---

Acked-by: Andrii Nakryiko <andriin at fb.com>

>  kernel/bpf/btf.c      | 28 ++++++++++++++++++++--------
>  kernel/bpf/verifier.c | 31 +++++++++++++++++++++++++++++++
>  2 files changed, 51 insertions(+), 8 deletions(-)
>

[...]