lkml.org 
[lkml]   [2020]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH bpf-next 1/2] bpf: Expose bpf_get_socket_cookie to tracing programs
From
Date


On 11/26/20 9:02 AM, Florent Revest wrote:
> This creates a new helper proto because the existing
> bpf_get_socket_cookie_sock_proto has a ARG_PTR_TO_CTX argument and only
> works for BPF programs where the context is a sock.
>
> This helper could also be useful to other BPF program types such as LSM.
>
> Signed-off-by: Florent Revest <revest@google.com>
> ---
> kernel/trace/bpf_trace.c | 4 ++++
> net/core/filter.c | 7 +++++++
> 2 files changed, 11 insertions(+)
>
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index d255bc9b2bfa..14ad96579813 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -1725,6 +1725,8 @@ raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
> }
> }
>
> +extern const struct bpf_func_proto bpf_get_socket_cookie_sock_tracing_proto;
> +
> const struct bpf_func_proto *
> tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
> {
> @@ -1748,6 +1750,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
> return &bpf_sk_storage_get_tracing_proto;
> case BPF_FUNC_sk_storage_delete:
> return &bpf_sk_storage_delete_tracing_proto;
> + case BPF_FUNC_get_socket_cookie:
> + return &bpf_get_socket_cookie_sock_tracing_proto;
> #endif
> case BPF_FUNC_seq_printf:
> return prog->expected_attach_type == BPF_TRACE_ITER ?
> diff --git a/net/core/filter.c b/net/core/filter.c
> index 2ca5eecebacf..177c4e5e529d 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -4631,6 +4631,13 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
> .arg1_type = ARG_PTR_TO_CTX,
> };
>
> +const struct bpf_func_proto bpf_get_socket_cookie_sock_tracing_proto = {
> + .func = bpf_get_socket_cookie_sock,
> + .gpl_only = false,
> + .ret_type = RET_INTEGER,
> + .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
> +};

This seems correct to me. Could you add another helper description in
uapi bpf.h? Currently we already have:
u64 bpf_get_socket_cookie(struct sk_buff *skb)
u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx)

The btf-id based helper will be something like below
u64 bpf_get_socket_cookie(void *sk)


> +
> BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
> {
> return __sock_gen_cookie(ctx->sk);
>

\
 
 \ /
  Last update: 2020-11-27 09:11    [W:0.082 / U:0.812 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site