On Fri, Sep 27, 2024 at 12:54 AM +02, Michal Luczaj wrote:
On 9/24/24 12:25, Michal Luczaj wrote:
On 8/19/24 22:05, Jakub Sitnicki wrote:
On Wed, Aug 14, 2024 at 06:14 PM +02, Michal Luczaj wrote:
On 8/6/24 19:45, Jakub Sitnicki wrote:
On Tue, Aug 06, 2024 at 07:18 PM +02, Michal Luczaj wrote:
Great, thanks for the review. With this completed, I guess we can unwind the (mail) stack to [1]. Is that ingress-to-local et al. something you wanted to take care of yourself or can I give it a try? [1] https://lore.kernel.org/netdev/87msmqn9ws.fsf@cloudflare.com/
I haven't stated any work on. You're welcome to tackle that.
All I have is a toy test that I've used to generate the redirect matrix. Perhaps it can serve as inspiration:
All right, please let me know if this is more or less what you meant and I'll post the whole series for a review (+patch to purge sockmap_listen of redir tests, fix misnomers). [...]
Gave it a look as promised. It makes sense to me as well to put these tests in a new module. There will be some overlap with sockmap_listen, which has diverged from its inital scope, but we can dedup that later.
One thought that I had is that it could make sense to test the not supported redirect combos (and expect an error). Sometimes folks make changes and enable some parts of the API by accient.
All right, so I did what sockmap_listen does: check test_sockmap_listen.c:verdict_map[SK_PASS] to see if the redirect took place for a given combo. And that works well... except for skb/msg to ingress af_vsock. Even though this is unsupported and no redirect actually happens, verdict appears to be SK_PASS. Is this correct?
Here's a follow up: my guess is that some checks are missing. I'm not sure if it's the best approach, but this fixes things for me:
So you have already found a bug with a negative test. Nice.
Your patch makes sense to me.
FYI, I've started a GH repo for anciallary materials for sockmap. Code samples, pointers to resources, a backlog of stuff to do (?). Inspired by the xdp-project repo:
https://github.com/xdp-project/xdp-project
We can move it to a dedicated project namespace, right now it's at:
https://github.com/jsitnicki/sockmap-project/
Feel free to add stuff there.
diff --git a/include/net/sock.h b/include/net/sock.h index c58ca8dd561b..c87295f3476d 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2715,6 +2715,11 @@ static inline bool sk_is_stream_unix(const struct sock *sk) return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM; } +static inline bool sk_is_vsock(const struct sock *sk) +{
- return sk->sk_family == AF_VSOCK;
+}
/**
- sk_eat_skb - Release a skb if it is no longer needed
- @sk: socket to eat this skb from
diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 242c91a6e3d3..07d6aa4e39ef 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -647,6 +647,8 @@ BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, 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_vsock(sk))
return SK_DROP;skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); return SK_PASS; @@ -675,6 +677,8 @@ BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg *, msg, return SK_DROP; if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk)) return SK_DROP;
- if (sk_is_vsock(sk))
return SK_DROP;msg->flags = flags; msg->sk_redir = sk; @@ -1249,6 +1253,8 @@ BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, 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_vsock(sk))
return SK_DROP;skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); return SK_PASS; @@ -1277,6 +1283,8 @@ BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg *, msg, return SK_DROP; if (!(flags & BPF_F_INGRESS) && !sk_is_tcp(sk)) return SK_DROP;
- if (sk_is_vsock(sk))
return SK_DROP;msg->flags = flags; msg->sk_redir = sk;