On 10/9/24 2:20 PM, Michal Luczaj wrote:
Don't mislead the callers of bpf_{sk,msg}_redirect_{map,hash}(): make sure
to immediately and visibly fail the forwarding of unsupported af_vsock
packets.
Fixes: 634f1a7110b4 ("vsock: support sockmap")
Signed-off-by: Michal Luczaj <mhal@xxxxxxx>
---
include/net/sock.h | 5 +++++
net/core/sock_map.c | 8 ++++++++
2 files changed, 13 insertions(+)
diff --git a/include/net/sock.h b/include/net/sock.h
index c58ca8dd561b7312ffc0836585c04d9fe917a124..c87295f3476db23934d4fcbeabc7851c61ad2bc4 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 242c91a6e3d3870ec6da6fa095d180a933d1d3d4..07d6aa4e39ef606aab33bd0d95711ecf156596b9 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;
Jakub Sitnicki, I think you have been on another thread about this change.
Please help to take a look and ack if it looks good. Thanks.
msg->flags = flags;
msg->sk_redir = sk;