diff options
Diffstat (limited to 'net/mptcp/options.c')
| -rw-r--r-- | net/mptcp/options.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 9d7fa93fe0cf..b2f018d32840 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -626,6 +626,12 @@ bool mptcp_established_options(struct sock *sk, struct sk_buff *skb, if (unlikely(mptcp_check_fallback(sk))) return false; + /* prevent adding of any MPTCP related options on reset packet + * until we support MP_TCPRST/MP_FASTCLOSE + */ + if (unlikely(skb && TCP_SKB_CB(skb)->tcp_flags & TCPHDR_RST)) + return false; + if (mptcp_established_options_mp(sk, skb, &opt_size, remaining, opts)) ret = true; else if (mptcp_established_options_dss(sk, skb, &opt_size, remaining, @@ -676,7 +682,7 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size, return false; } -static bool check_fully_established(struct mptcp_sock *msk, struct sock *sk, +static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, struct mptcp_subflow_context *subflow, struct sk_buff *skb, struct mptcp_options_received *mp_opt) @@ -693,15 +699,20 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *sk, TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq && subflow->mp_join && mp_opt->mp_join && READ_ONCE(msk->pm.server_side)) - tcp_send_ack(sk); + tcp_send_ack(ssk); goto fully_established; } - /* we should process OoO packets before the first subflow is fully - * established, but not expected for MP_JOIN subflows + /* we must process OoO packets before the first subflow is fully + * established. OoO packets are instead a protocol violation + * for MP_JOIN subflows as the peer must not send any data + * before receiving the forth ack - cfr. RFC 8684 section 3.2. */ - if (TCP_SKB_CB(skb)->seq != subflow->ssn_offset + 1) + if (TCP_SKB_CB(skb)->seq != subflow->ssn_offset + 1) { + if (subflow->mp_join) + goto reset; return subflow->mp_capable; + } if (mp_opt->dss && mp_opt->use_ack) { /* subflows are fully established as soon as we get any @@ -713,9 +724,12 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *sk, } /* If the first established packet does not contain MP_CAPABLE + data - * then fallback to TCP + * then fallback to TCP. Fallback scenarios requires a reset for + * MP_JOIN subflows. */ if (!mp_opt->mp_capable) { + if (subflow->mp_join) + goto reset; subflow->mp_capable = 0; pr_fallback(msk); __mptcp_do_fallback(msk); @@ -732,12 +746,16 @@ fully_established: subflow->pm_notified = 1; if (subflow->mp_join) { - clear_3rdack_retransmission(sk); + clear_3rdack_retransmission(ssk); mptcp_pm_subflow_established(msk, subflow); } else { mptcp_pm_fully_established(msk); } return true; + +reset: + mptcp_subflow_reset(ssk); + return false; } static u64 expand_ack(u64 old_ack, u64 cur_ack, bool use_64bit) |