diff options
author | David S. Miller <davem@davemloft.net> | 2021-06-07 23:01:52 +0300 |
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committer | David S. Miller <davem@davemloft.net> | 2021-06-07 23:01:52 +0300 |
commit | 126285651b7f95282a0afe3a1b0221419b31d989 (patch) | |
tree | e5d547255814a5ed55b6b74be3155464598b39f2 /net/mptcp/subflow.c | |
parent | 9977d6f56bacc9784654be4d0f4d27b368f57f5b (diff) | |
parent | 3822d0670c9d4342794d73e0d0e615322b40438e (diff) | |
download | linux-126285651b7f95282a0afe3a1b0221419b31d989.tar.xz |
Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net
Bug fixes overlapping feature additions and refactoring, mostly.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp/subflow.c')
-rw-r--r-- | net/mptcp/subflow.c | 79 |
1 files changed, 40 insertions, 39 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 2a58503e55bd..33956337c46b 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -630,21 +630,20 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk, /* if the sk is MP_CAPABLE, we try to fetch the client key */ if (subflow_req->mp_capable) { - if (TCP_SKB_CB(skb)->seq != subflow_req->ssn_offset + 1) { - /* here we can receive and accept an in-window, - * out-of-order pkt, which will not carry the MP_CAPABLE - * opt even on mptcp enabled paths - */ - goto create_msk; - } - + /* we can receive and accept an in-window, out-of-order pkt, + * which may not carry the MP_CAPABLE opt even on mptcp enabled + * paths: always try to extract the peer key, and fallback + * for packets missing it. + * Even OoO DSS packets coming legitly after dropped or + * reordered MPC will cause fallback, but we don't have other + * options. + */ mptcp_get_options(skb, &mp_opt); if (!mp_opt.mp_capable) { fallback = true; goto create_child; } -create_msk: new_msk = mptcp_sk_clone(listener->conn, &mp_opt, req); if (!new_msk) fallback = true; @@ -1012,21 +1011,11 @@ static bool subflow_check_data_avail(struct sock *ssk) status = get_mapping_status(ssk, msk); trace_subflow_check_data_avail(status, skb_peek(&ssk->sk_receive_queue)); - if (status == MAPPING_INVALID) { - ssk->sk_err = EBADMSG; - goto fatal; - } - if (status == MAPPING_DUMMY) { - __mptcp_do_fallback(msk); - skb = skb_peek(&ssk->sk_receive_queue); - subflow->map_valid = 1; - subflow->map_seq = READ_ONCE(msk->ack_seq); - subflow->map_data_len = skb->len; - subflow->map_subflow_seq = tcp_sk(ssk)->copied_seq - - subflow->ssn_offset; - subflow->data_avail = MPTCP_SUBFLOW_DATA_AVAIL; - return true; - } + if (unlikely(status == MAPPING_INVALID)) + goto fallback; + + if (unlikely(status == MAPPING_DUMMY)) + goto fallback; if (status != MAPPING_OK) goto no_data; @@ -1039,10 +1028,8 @@ static bool subflow_check_data_avail(struct sock *ssk) * MP_CAPABLE-based mapping */ if (unlikely(!READ_ONCE(msk->can_ack))) { - if (!subflow->mpc_map) { - ssk->sk_err = EBADMSG; - goto fatal; - } + if (!subflow->mpc_map) + goto fallback; WRITE_ONCE(msk->remote_key, subflow->remote_key); WRITE_ONCE(msk->ack_seq, subflow->map_seq); WRITE_ONCE(msk->can_ack, true); @@ -1070,17 +1057,31 @@ static bool subflow_check_data_avail(struct sock *ssk) no_data: subflow_sched_work_if_closed(msk, ssk); return false; -fatal: - /* fatal protocol error, close the socket */ - /* This barrier is coupled with smp_rmb() in tcp_poll() */ - smp_wmb(); - ssk->sk_error_report(ssk); - tcp_set_state(ssk, TCP_CLOSE); - subflow->reset_transient = 0; - subflow->reset_reason = MPTCP_RST_EMPTCP; - tcp_send_active_reset(ssk, GFP_ATOMIC); - subflow->data_avail = 0; - return false; + +fallback: + /* RFC 8684 section 3.7. */ + if (subflow->mp_join || subflow->fully_established) { + /* fatal protocol error, close the socket. + * subflow_error_report() will introduce the appropriate barriers + */ + ssk->sk_err = EBADMSG; + ssk->sk_error_report(ssk); + tcp_set_state(ssk, TCP_CLOSE); + subflow->reset_transient = 0; + subflow->reset_reason = MPTCP_RST_EMPTCP; + tcp_send_active_reset(ssk, GFP_ATOMIC); + subflow->data_avail = 0; + return false; + } + + __mptcp_do_fallback(msk); + skb = skb_peek(&ssk->sk_receive_queue); + subflow->map_valid = 1; + subflow->map_seq = READ_ONCE(msk->ack_seq); + subflow->map_data_len = skb->len; + subflow->map_subflow_seq = tcp_sk(ssk)->copied_seq - subflow->ssn_offset; + subflow->data_avail = MPTCP_SUBFLOW_DATA_AVAIL; + return true; } bool mptcp_subflow_data_available(struct sock *sk) |