From: Geliang Tang <tanggeliang@kylinos.cn>

Drop the NULL check as Martin suggested.

Use the "struct sock *sk" instead of "struct mptcp-sock *msk" as the
argument in the bpf_iter_mptcp_subflow_new as Martin suggested.

Use msk_owned_by_me().

v2:
 - check the owner before assigning the msk as Mat suggested.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/bpf.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c
index 7e9d9c9a04cf..c0ac11f611b0 100644
--- a/net/mptcp/bpf.c
+++ b/net/mptcp/bpf.c
@@ -235,24 +235,26 @@ bpf_mptcp_subflow_ctx(const struct sock *sk)
 
 __bpf_kfunc static int
 bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it,
-			   struct mptcp_sock *msk)
+			   struct sock *sk)
 {
 	struct bpf_iter_mptcp_subflow_kern *kit = (void *)it;
-	struct sock *sk = (struct sock *)msk;
+	struct mptcp_sock *msk;
 
 	BUILD_BUG_ON(sizeof(struct bpf_iter_mptcp_subflow_kern) >
 		     sizeof(struct bpf_iter_mptcp_subflow));
 	BUILD_BUG_ON(__alignof__(struct bpf_iter_mptcp_subflow_kern) !=
 		     __alignof__(struct bpf_iter_mptcp_subflow));
 
-	kit->msk = msk;
-	if (!msk)
+	if (unlikely(!sk || !sk_fullsock(sk)))
 		return -EINVAL;
 
-	if (!sock_owned_by_user_nocheck(sk) &&
-	    !spin_is_locked(&sk->sk_lock.slock))
+	if (sk->sk_protocol != IPPROTO_MPTCP)
 		return -EINVAL;
 
+	msk = mptcp_sk(sk);
+	msk_owned_by_me(msk);
+
+	kit->msk = msk;
 	kit->pos = &msk->conn_list;
 	return 0;
 }
-- 
2.43.0