diff options
Diffstat (limited to 'net/mptcp/subflow.c')
| -rw-r--r-- | net/mptcp/subflow.c | 127 |
1 files changed, 98 insertions, 29 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 8841e8cd9ad8..63e8892ec807 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -843,7 +843,8 @@ enum mapping_status { MAPPING_INVALID, MAPPING_EMPTY, MAPPING_DATA_FIN, - MAPPING_DUMMY + MAPPING_DUMMY, + MAPPING_BAD_CSUM }; static void dbg_bad_map(struct mptcp_subflow_context *subflow, u32 ssn) @@ -958,11 +959,7 @@ static enum mapping_status validate_data_csum(struct sock *ssk, struct sk_buff * subflow->map_data_csum); if (unlikely(csum)) { MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DATACSUMERR); - if (subflow->mp_join || subflow->valid_csum_seen) { - subflow->send_mp_fail = 1; - MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_MPFAILTX); - } - return subflow->mp_join ? MAPPING_INVALID : MAPPING_DUMMY; + return MAPPING_BAD_CSUM; } subflow->valid_csum_seen = 1; @@ -974,7 +971,6 @@ static enum mapping_status get_mapping_status(struct sock *ssk, { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); bool csum_reqd = READ_ONCE(msk->csum_enabled); - struct sock *sk = (struct sock *)msk; struct mptcp_ext *mpext; struct sk_buff *skb; u16 data_len; @@ -1016,9 +1012,6 @@ static enum mapping_status get_mapping_status(struct sock *ssk, pr_debug("infinite mapping received"); MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX); subflow->map_data_len = 0; - if (!sock_flag(ssk, SOCK_DEAD)) - sk_stop_timer(sk, &sk->sk_timer); - return MAPPING_INVALID; } @@ -1165,6 +1158,33 @@ static bool subflow_can_fallback(struct mptcp_subflow_context *subflow) return !subflow->fully_established; } +static void mptcp_subflow_fail(struct mptcp_sock *msk, struct sock *ssk) +{ + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + unsigned long fail_tout; + + /* greceful failure can happen only on the MPC subflow */ + if (WARN_ON_ONCE(ssk != READ_ONCE(msk->first))) + return; + + /* since the close timeout take precedence on the fail one, + * no need to start the latter when the first is already set + */ + if (sock_flag((struct sock *)msk, SOCK_DEAD)) + return; + + /* we don't need extreme accuracy here, use a zero fail_tout as special + * value meaning no fail timeout at all; + */ + fail_tout = jiffies + TCP_RTO_MAX; + if (!fail_tout) + fail_tout = 1; + WRITE_ONCE(subflow->fail_tout, fail_tout); + tcp_send_ack(ssk); + + mptcp_reset_timeout(msk, subflow->fail_tout); +} + static bool subflow_check_data_avail(struct sock *ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); @@ -1184,10 +1204,8 @@ 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 (unlikely(status == MAPPING_INVALID)) - goto fallback; - - if (unlikely(status == MAPPING_DUMMY)) + if (unlikely(status == MAPPING_INVALID || status == MAPPING_DUMMY || + status == MAPPING_BAD_CSUM)) goto fallback; if (status != MAPPING_OK) @@ -1229,22 +1247,17 @@ no_data: fallback: if (!__mptcp_check_fallback(msk)) { /* RFC 8684 section 3.7. */ - if (subflow->send_mp_fail) { + if (status == MAPPING_BAD_CSUM && + (subflow->mp_join || subflow->valid_csum_seen)) { + subflow->send_mp_fail = 1; + if (!READ_ONCE(msk->allow_infinite_fallback)) { - ssk->sk_err = EBADMSG; - tcp_set_state(ssk, TCP_CLOSE); subflow->reset_transient = 0; subflow->reset_reason = MPTCP_RST_EMIDDLEBOX; - tcp_send_active_reset(ssk, GFP_ATOMIC); - while ((skb = skb_peek(&ssk->sk_receive_queue))) - sk_eat_skb(ssk, skb); - } else if (!sock_flag(ssk, SOCK_DEAD)) { - WRITE_ONCE(subflow->mp_fail_response_expect, true); - sk_reset_timer((struct sock *)msk, - &((struct sock *)msk)->sk_timer, - jiffies + TCP_RTO_MAX); + goto reset; } - WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); + mptcp_subflow_fail(msk, ssk); + WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_DATA_AVAIL); return true; } @@ -1252,16 +1265,20 @@ fallback: /* fatal protocol error, close the socket. * subflow_error_report() will introduce the appropriate barriers */ - ssk->sk_err = EBADMSG; - tcp_set_state(ssk, TCP_CLOSE); subflow->reset_transient = 0; subflow->reset_reason = MPTCP_RST_EMPTCP; + +reset: + ssk->sk_err = EBADMSG; + tcp_set_state(ssk, TCP_CLOSE); + while ((skb = skb_peek(&ssk->sk_receive_queue))) + sk_eat_skb(ssk, skb); tcp_send_active_reset(ssk, GFP_ATOMIC); WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA); return false; } - __mptcp_do_fallback(msk); + mptcp_do_fallback(ssk); } skb = skb_peek(&ssk->sk_receive_queue); @@ -1706,6 +1723,58 @@ static void subflow_state_change(struct sock *sk) } } +void mptcp_subflow_queue_clean(struct sock *listener_ssk) +{ + struct request_sock_queue *queue = &inet_csk(listener_ssk)->icsk_accept_queue; + struct mptcp_sock *msk, *next, *head = NULL; + struct request_sock *req; + + /* build a list of all unaccepted mptcp sockets */ + spin_lock_bh(&queue->rskq_lock); + for (req = queue->rskq_accept_head; req; req = req->dl_next) { + struct mptcp_subflow_context *subflow; + struct sock *ssk = req->sk; + struct mptcp_sock *msk; + + if (!sk_is_mptcp(ssk)) + continue; + + subflow = mptcp_subflow_ctx(ssk); + if (!subflow || !subflow->conn) + continue; + + /* skip if already in list */ + msk = mptcp_sk(subflow->conn); + if (msk->dl_next || msk == head) + continue; + + msk->dl_next = head; + head = msk; + } + spin_unlock_bh(&queue->rskq_lock); + if (!head) + return; + + /* can't acquire the msk socket lock under the subflow one, + * or will cause ABBA deadlock + */ + release_sock(listener_ssk); + + for (msk = head; msk; msk = next) { + struct sock *sk = (struct sock *)msk; + bool slow; + + slow = lock_sock_fast_nested(sk); + next = msk->dl_next; + msk->first = NULL; + msk->dl_next = NULL; + unlock_sock_fast(sk, slow); + } + + /* we are still under the listener msk socket lock */ + lock_sock_nested(listener_ssk, SINGLE_DEPTH_NESTING); +} + static int subflow_ulp_init(struct sock *sk) { struct inet_connection_sock *icsk = inet_csk(sk); |