Re: [PATCH] bpf: cg_skb add get classid helper

[Martin KaFai Lau <martin.lau@linux.dev>]

On 8/14/24 2:50 AM, Feng zhou wrote:
> From: Feng Zhou <zhoufeng.zf@bytedance.com>
> 
> At cg_skb hook point, can get classid for v1 or v2, allowing
> users to do more functions such as acl.
> 
> Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com>
> ---
>   net/core/filter.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/net/core/filter.c b/net/core/filter.c
> index 78a6f746ea0b..d69ba589882f 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -8111,6 +8111,12 @@ cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
>   		return &bpf_get_listener_sock_proto;
>   	case BPF_FUNC_skb_ecn_set_ce:
>   		return &bpf_skb_ecn_set_ce_proto;
> +	case BPF_FUNC_get_cgroup_classid:
> +		return &bpf_get_cgroup_classid_proto;
> +#endif
> +#ifdef CONFIG_CGROUP_NET_CLASSID
> +	case BPF_FUNC_skb_cgroup_classid:
> +		return &bpf_skb_cgroup_classid_proto;

With this bpf_skb_cgroup_classid_proto, is the above 
bpf_get_cgroup_classid_proto necessary?
The cg_skb hook must have a skb->sk.

Please add a selftest and tag the subject with bpf-next.

pw-bot: cr

>   #endif
>   	default:
>   		return sk_filter_func_proto(func_id, prog);