Re: [PATCH bpf] bpf, sockmap: Reject sk_msg egress redirects to non-TCP sockets

[Kui-Feng Lee <sinquersw@xxxxxxxxx>]

On 9/20/23 03:20, Jakub Sitnicki wrote:
> diff --git a/net/core/sock_map.c b/net/core/sock_map.c
> index cb11750b1df5..4292c2ed1828 100644
> --- a/net/core/sock_map.c
> +++ b/net/core/sock_map.c
> @@ -668,6 +668,8 @@ BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg *, msg,
>   	sk = __sock_map_lookup_elem(map, key);
>   	if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
>   		return SK_DROP;
> +	if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk))
> +		return SK_DROP;
>   
>   	msg->flags = flags;
>   	msg->sk_redir = sk;
> @@ -1267,6 +1269,8 @@ BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg *, msg,
>   	sk = __sock_hash_lookup_elem(map, key);
>   	if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
>   		return SK_DROP;
> +	if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk))
> +		return SK_DROP;
>   
>   	msg->flags = flags;
>   	msg->sk_redir = sk;

Just be curious! Can it happen to other socket types?
I mean to redirect a msg from a sk of any type to one of another type.