diff options
Diffstat (limited to 'net/mptcp/options.c')
| -rw-r--r-- | net/mptcp/options.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 45acd877bef3..fd2c3150e591 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -334,6 +334,8 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, struct mptcp_sock *msk; unsigned int ack_size; bool ret = false; + bool can_ack; + u64 ack_seq; u8 tcp_fin; if (skb) { @@ -360,9 +362,22 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, ret = true; } + /* passive sockets msk will set the 'can_ack' after accept(), even + * if the first subflow may have the already the remote key handy + */ + can_ack = true; opts->ext_copy.use_ack = 0; msk = mptcp_sk(subflow->conn); - if (!msk || !READ_ONCE(msk->can_ack)) { + if (likely(msk && READ_ONCE(msk->can_ack))) { + ack_seq = msk->ack_seq; + } else if (subflow->can_ack) { + mptcp_crypto_key_sha(subflow->remote_key, NULL, &ack_seq); + ack_seq++; + } else { + can_ack = false; + } + + if (unlikely(!can_ack)) { *size = ALIGN(dss_size, 4); return ret; } @@ -375,7 +390,7 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb, dss_size += ack_size; - opts->ext_copy.data_ack = msk->ack_seq; + opts->ext_copy.data_ack = ack_seq; opts->ext_copy.ack64 = 1; opts->ext_copy.use_ack = 1; |