6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Michal Luczaj <mhal@xxxxxxx>
[ Upstream commit 9c5bd93edf7b8834aecaa7c340b852d5990d7c78 ]
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>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
Link: https://lore.kernel.org/bpf/20241013-vsock-fixes-for-redir-v2-1-d6577bbfe742@xxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 2d4149075091b..f127fc268a5ef 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 724b6856fcc3e..219fd8f1ca2a4 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -656,6 +656,8 @@ 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;
@@ -684,6 +686,8 @@ 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;
@@ -1258,6 +1262,8 @@ 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;
@@ -1286,6 +1292,8 @@ 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;
--
2.43.0
