diff options
| -rw-r--r-- | net/mptcp/subflow.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index ada04df6f99f..e645483d1200 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -53,6 +53,12 @@ static void subflow_generate_hmac(u64 key1, u64 key2, u32 nonce1, u32 nonce2, mptcp_crypto_hmac_sha(key1, key2, msg, 8, hmac); } +static bool mptcp_can_accept_new_subflow(const struct mptcp_sock *msk) +{ + return mptcp_is_fully_established((void *)msk) && + READ_ONCE(msk->pm.accept_subflow); +} + /* validate received token and create truncated hmac and nonce for SYN-ACK */ static struct mptcp_sock *subflow_token_join_request(struct request_sock *req, const struct sk_buff *skb) @@ -443,6 +449,7 @@ create_msk: } else if (subflow_req->mp_join) { mptcp_get_options(skb, &mp_opt); if (!mp_opt.mp_join || + !mptcp_can_accept_new_subflow(subflow_req->msk) || !subflow_hmac_valid(req, &mp_opt)) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKMAC); fallback = true; |