diff options
Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r-- | net/ipv4/tcp_input.c | 432 |
1 files changed, 307 insertions, 125 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index ff6cd98ce8d5..4cf2f7bb2802 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -78,6 +78,7 @@ #include <linux/errqueue.h> #include <trace/events/tcp.h> #include <linux/static_key.h> +#include <net/busy_poll.h> int sysctl_tcp_max_orphans __read_mostly = NR_FILE; @@ -111,6 +112,25 @@ int sysctl_tcp_max_orphans __read_mostly = NR_FILE; #define REXMIT_LOST 1 /* retransmit packets marked lost */ #define REXMIT_NEW 2 /* FRTO-style transmit of unsent/new packets */ +#if IS_ENABLED(CONFIG_TLS_DEVICE) +static DEFINE_STATIC_KEY_FALSE(clean_acked_data_enabled); + +void clean_acked_data_enable(struct inet_connection_sock *icsk, + void (*cad)(struct sock *sk, u32 ack_seq)) +{ + icsk->icsk_clean_acked = cad; + static_branch_inc(&clean_acked_data_enabled); +} +EXPORT_SYMBOL_GPL(clean_acked_data_enable); + +void clean_acked_data_disable(struct inet_connection_sock *icsk) +{ + static_branch_dec(&clean_acked_data_enabled); + icsk->icsk_clean_acked = NULL; +} +EXPORT_SYMBOL_GPL(clean_acked_data_disable); +#endif + static void tcp_gro_dev_warn(struct sock *sk, const struct sk_buff *skb, unsigned int len) { @@ -184,24 +204,27 @@ static void tcp_measure_rcv_mss(struct sock *sk, const struct sk_buff *skb) } } -static void tcp_incr_quickack(struct sock *sk) +static void tcp_incr_quickack(struct sock *sk, unsigned int max_quickacks) { struct inet_connection_sock *icsk = inet_csk(sk); unsigned int quickacks = tcp_sk(sk)->rcv_wnd / (2 * icsk->icsk_ack.rcv_mss); if (quickacks == 0) quickacks = 2; + quickacks = min(quickacks, max_quickacks); if (quickacks > icsk->icsk_ack.quick) - icsk->icsk_ack.quick = min(quickacks, TCP_MAX_QUICKACKS); + icsk->icsk_ack.quick = quickacks; } -static void tcp_enter_quickack_mode(struct sock *sk) +void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks) { struct inet_connection_sock *icsk = inet_csk(sk); - tcp_incr_quickack(sk); + + tcp_incr_quickack(sk, max_quickacks); icsk->icsk_ack.pingpong = 0; icsk->icsk_ack.ato = TCP_ATO_MIN; } +EXPORT_SYMBOL(tcp_enter_quickack_mode); /* Send ACKs quickly, if "quick" count is not exhausted * and the session is not interactive. @@ -222,10 +245,17 @@ static void tcp_ecn_queue_cwr(struct tcp_sock *tp) tp->ecn_flags |= TCP_ECN_QUEUE_CWR; } -static void tcp_ecn_accept_cwr(struct tcp_sock *tp, const struct sk_buff *skb) +static void tcp_ecn_accept_cwr(struct sock *sk, const struct sk_buff *skb) { - if (tcp_hdr(skb)->cwr) - tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR; + if (tcp_hdr(skb)->cwr) { + tcp_sk(sk)->ecn_flags &= ~TCP_ECN_DEMAND_CWR; + + /* If the sender is telling us it has entered CWR, then its + * cwnd may be very low (even just 1 packet), so we should ACK + * immediately. + */ + inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW; + } } static void tcp_ecn_withdraw_cwr(struct tcp_sock *tp) @@ -233,8 +263,10 @@ static void tcp_ecn_withdraw_cwr(struct tcp_sock *tp) tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR; } -static void __tcp_ecn_check_ce(struct tcp_sock *tp, const struct sk_buff *skb) +static void __tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) { + struct tcp_sock *tp = tcp_sk(sk); + switch (TCP_SKB_CB(skb)->ip_dsfield & INET_ECN_MASK) { case INET_ECN_NOT_ECT: /* Funny extension: if ECT is not set on a segment, @@ -242,31 +274,31 @@ static void __tcp_ecn_check_ce(struct tcp_sock *tp, const struct sk_buff *skb) * it is probably a retransmit. */ if (tp->ecn_flags & TCP_ECN_SEEN) - tcp_enter_quickack_mode((struct sock *)tp); + tcp_enter_quickack_mode(sk, 2); break; case INET_ECN_CE: - if (tcp_ca_needs_ecn((struct sock *)tp)) - tcp_ca_event((struct sock *)tp, CA_EVENT_ECN_IS_CE); + if (tcp_ca_needs_ecn(sk)) + tcp_ca_event(sk, CA_EVENT_ECN_IS_CE); if (!(tp->ecn_flags & TCP_ECN_DEMAND_CWR)) { /* Better not delay acks, sender can have a very low cwnd */ - tcp_enter_quickack_mode((struct sock *)tp); + tcp_enter_quickack_mode(sk, 2); tp->ecn_flags |= TCP_ECN_DEMAND_CWR; } tp->ecn_flags |= TCP_ECN_SEEN; break; default: - if (tcp_ca_needs_ecn((struct sock *)tp)) - tcp_ca_event((struct sock *)tp, CA_EVENT_ECN_NO_CE); + if (tcp_ca_needs_ecn(sk)) + tcp_ca_event(sk, CA_EVENT_ECN_NO_CE); tp->ecn_flags |= TCP_ECN_SEEN; break; } } -static void tcp_ecn_check_ce(struct tcp_sock *tp, const struct sk_buff *skb) +static void tcp_ecn_check_ce(struct sock *sk, const struct sk_buff *skb) { - if (tp->ecn_flags & TCP_ECN_OK) - __tcp_ecn_check_ce(tp, skb); + if (tcp_sk(sk)->ecn_flags & TCP_ECN_OK) + __tcp_ecn_check_ce(sk, skb); } static void tcp_ecn_rcv_synack(struct tcp_sock *tp, const struct tcphdr *th) @@ -559,9 +591,12 @@ static inline void tcp_rcv_rtt_measure_ts(struct sock *sk, { struct tcp_sock *tp = tcp_sk(sk); - if (tp->rx_opt.rcv_tsecr && - (TCP_SKB_CB(skb)->end_seq - - TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss)) { + if (tp->rx_opt.rcv_tsecr == tp->rcv_rtt_last_tsecr) + return; + tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr; + + if (TCP_SKB_CB(skb)->end_seq - + TCP_SKB_CB(skb)->seq >= inet_csk(sk)->icsk_ack.rcv_mss) { u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr; u32 delta_us; @@ -582,6 +617,8 @@ void tcp_rcv_space_adjust(struct sock *sk) u32 copied; int time; + trace_tcp_rcv_space_adjust(sk); + tcp_mstamp_refresh(tp); time = tcp_stamp_us_delta(tp->tcp_mstamp, tp->rcvq_space.time); if (time < (tp->rcv_rtt_est.rtt_us >> 3) || tp->rcv_rtt_est.rtt_us == 0) @@ -665,7 +702,7 @@ static void tcp_event_data_recv(struct sock *sk, struct sk_buff *skb) /* The _first_ data packet received, initialize * delayed ACK engine. */ - tcp_incr_quickack(sk); + tcp_incr_quickack(sk, TCP_MAX_QUICKACKS); icsk->icsk_ack.ato = TCP_ATO_MIN; } else { int m = now - icsk->icsk_ack.lrcvtime; @@ -681,13 +718,13 @@ static void tcp_event_data_recv(struct sock *sk, struct sk_buff *skb) /* Too long gap. Apparently sender failed to * restart window, so that we send ACKs quickly. */ - tcp_incr_quickack(sk); + tcp_incr_quickack(sk, TCP_MAX_QUICKACKS); sk_mem_reclaim(sk); } } icsk->icsk_ack.lrcvtime = now; - tcp_ecn_check_ce(tp, skb); + tcp_ecn_check_ce(sk, skb); if (skb->len >= 128) tcp_grow_window(sk, skb); @@ -844,6 +881,7 @@ static void tcp_dsack_seen(struct tcp_sock *tp) { tp->rx_opt.sack_ok |= TCP_DSACK_SEEN; tp->rack.dsack_seen = 1; + tp->dsack_dups++; } /* It's reordering when higher sequence was delivered (i.e. sacked) before @@ -875,8 +913,8 @@ static void tcp_check_sack_reordering(struct sock *sk, const u32 low_seq, sock_net(sk)->ipv4.sysctl_tcp_max_reordering); } - tp->rack.reord = 1; /* This exciting event is worth to be remembered. 8) */ + tp->reord_seen++; NET_INC_STATS(sock_net(sk), ts ? LINUX_MIB_TCPTSREORDER : LINUX_MIB_TCPSACKREORDER); } @@ -1358,9 +1396,6 @@ static struct sk_buff *tcp_shift_skb_data(struct sock *sk, struct sk_buff *skb, int len; int in_sack; - if (!sk_can_gso(sk)) - goto fallback; - /* Normally R but no L won't result in plain S */ if (!dup_sack && (TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_RETRANS)) == TCPCB_SACKED_RETRANS) @@ -1843,6 +1878,7 @@ static void tcp_check_reno_reordering(struct sock *sk, const int addend) tp->reordering = min_t(u32, tp->packets_out + addend, sock_net(sk)->ipv4.sysctl_tcp_max_reordering); + tp->reord_seen++; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRENOREORDER); } @@ -1899,19 +1935,54 @@ static inline void tcp_init_undo(struct tcp_sock *tp) tp->undo_retrans = tp->retrans_out ? : -1; } -/* Enter Loss state. If we detect SACK reneging, forget all SACK information +static bool tcp_is_rack(const struct sock *sk) +{ + return sock_net(sk)->ipv4.sysctl_tcp_recovery & TCP_RACK_LOSS_DETECTION; +} + +/* If we detect SACK reneging, forget all SACK information * and reset tags completely, otherwise preserve SACKs. If receiver * dropped its ofo queue, we will know this due to reneging detection. */ +static void tcp_timeout_mark_lost(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct sk_buff *skb, *head; + bool is_reneg; /* is receiver reneging on SACKs? */ + + head = tcp_rtx_queue_head(sk); + is_reneg = head && (TCP_SKB_CB(head)->sacked & TCPCB_SACKED_ACKED); + if (is_reneg) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING); + tp->sacked_out = 0; + /* Mark SACK reneging until we recover from this loss event. */ + tp->is_sack_reneg = 1; + } else if (tcp_is_reno(tp)) { + tcp_reset_reno_sack(tp); + } + + skb = head; + skb_rbtree_walk_from(skb) { + if (is_reneg) + TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED; + else if (tcp_is_rack(sk) && skb != head && + tcp_rack_skb_timeout(tp, skb, 0) > 0) + continue; /* Don't mark recently sent ones lost yet */ + tcp_mark_skb_lost(sk, skb); + } + tcp_verify_left_out(tp); + tcp_clear_all_retrans_hints(tp); +} + +/* Enter Loss state. */ void tcp_enter_loss(struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); - struct sk_buff *skb; bool new_recovery = icsk->icsk_ca_state < TCP_CA_Recovery; - bool is_reneg; /* is receiver reneging on SACKs? */ - bool mark_lost; + + tcp_timeout_mark_lost(sk); /* Reduce ssthresh if it has not yet been made inside this window. */ if (icsk->icsk_ca_state <= TCP_CA_Disorder || @@ -1923,40 +1994,10 @@ void tcp_enter_loss(struct sock *sk) tcp_ca_event(sk, CA_EVENT_LOSS); tcp_init_undo(tp); } - tp->snd_cwnd = 1; + tp->snd_cwnd = tcp_packets_in_flight(tp) + 1; tp->snd_cwnd_cnt = 0; tp->snd_cwnd_stamp = tcp_jiffies32; - tp->retrans_out = 0; - tp->lost_out = 0; - - if (tcp_is_reno(tp)) - tcp_reset_reno_sack(tp); - - skb = tcp_rtx_queue_head(sk); - is_reneg = skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED); - if (is_reneg) { - NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSACKRENEGING); - tp->sacked_out = 0; - /* Mark SACK reneging until we recover from this loss event. */ - tp->is_sack_reneg = 1; - } - tcp_clear_all_retrans_hints(tp); - - skb_rbtree_walk_from(skb) { - mark_lost = (!(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) || - is_reneg); - if (mark_lost) - tcp_sum_lost(tp, skb); - TCP_SKB_CB(skb)->sacked &= (~TCPCB_TAGBITS)|TCPCB_SACKED_ACKED; - if (mark_lost) { - TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED; - TCP_SKB_CB(skb)->sacked |= TCPCB_LOST; - tp->lost_out += tcp_skb_pcount(skb); - } - } - tcp_verify_left_out(tp); - /* Timeout in disordered state after receiving substantial DUPACKs * suggests that the degree of reordering is over-estimated. */ @@ -2123,7 +2164,7 @@ static bool tcp_time_to_recover(struct sock *sk, int flag) return true; /* Not-A-Trick#2 : Classic rule... */ - if (tcp_dupack_heuristics(tp) > tp->reordering) + if (!tcp_is_rack(sk) && tcp_dupack_heuristics(tp) > tp->reordering) return true; return false; @@ -2200,9 +2241,7 @@ static void tcp_update_scoreboard(struct sock *sk, int fast_rexmit) { struct tcp_sock *tp = tcp_sk(sk); - if (tcp_is_reno(tp)) { - tcp_mark_head_lost(sk, 1, 1); - } else { + if (tcp_is_sack(tp)) { int sacked_upto = tp->sacked_out - tp->reordering; if (sacked_upto >= 0) tcp_mark_head_lost(sk, sacked_upto, 0); @@ -2700,12 +2739,16 @@ static bool tcp_try_undo_partial(struct sock *sk, u32 prior_snd_una) return false; } -static void tcp_rack_identify_loss(struct sock *sk, int *ack_flag) +static void tcp_identify_packet_loss(struct sock *sk, int *ack_flag) { struct tcp_sock *tp = tcp_sk(sk); - /* Use RACK to detect loss */ - if (sock_net(sk)->ipv4.sysctl_tcp_recovery & TCP_RACK_LOSS_DETECTION) { + if (tcp_rtx_queue_empty(sk)) + return; + + if (unlikely(tcp_is_reno(tp))) { + tcp_newreno_mark_lost(sk, *ack_flag & FLAG_SND_UNA_ADVANCED); + } else if (tcp_is_rack(sk)) { u32 prior_retrans = tp->retrans_out; tcp_rack_mark_lost(sk); @@ -2801,11 +2844,11 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, tcp_try_keep_open(sk); return; } - tcp_rack_identify_loss(sk, ack_flag); + tcp_identify_packet_loss(sk, ack_flag); break; case TCP_CA_Loss: tcp_process_loss(sk, flag, is_dupack, rexmit); - tcp_rack_identify_loss(sk, ack_flag); + tcp_identify_packet_loss(sk, ack_flag); if (!(icsk->icsk_ca_state == TCP_CA_Open || (*ack_flag & FLAG_LOST_RETRANS))) return; @@ -2822,7 +2865,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, if (icsk->icsk_ca_state <= TCP_CA_Disorder) tcp_try_undo_dsack(sk); - tcp_rack_identify_loss(sk, ack_flag); + tcp_identify_packet_loss(sk, ack_flag); if (!tcp_time_to_recover(sk, flag)) { tcp_try_to_open(sk, flag); return; @@ -2844,7 +2887,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, fast_rexmit = 1; } - if (do_lost) + if (!tcp_is_rack(sk) && do_lost) tcp_update_scoreboard(sk, fast_rexmit); *rexmit = REXMIT_LOST; } @@ -3152,6 +3195,15 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack, if (tcp_is_reno(tp)) { tcp_remove_reno_sacks(sk, pkts_acked); + + /* If any of the cumulatively ACKed segments was + * retransmitted, non-SACK case cannot confirm that + * progress was due to original transmission due to + * lack of TCPCB_SACKED_ACKED bits even if some of + * the packets may have been never retransmitted. + */ + if (flag & FLAG_RETRANS_DATA_ACKED) + flag &= ~FLAG_ORIG_SACK_ACKED; } else { int delta; @@ -3420,7 +3472,7 @@ static void tcp_send_challenge_ack(struct sock *sk, const struct sk_buff *skb) static void tcp_store_ts_recent(struct tcp_sock *tp) { tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval; - tp->rx_opt.ts_recent_stamp = get_seconds(); + tp->rx_opt.ts_recent_stamp = ktime_get_seconds(); } static void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq) @@ -3499,6 +3551,22 @@ static void tcp_xmit_recovery(struct sock *sk, int rexmit) tcp_xmit_retransmit_queue(sk); } +/* Returns the number of packets newly acked or sacked by the current ACK */ +static u32 tcp_newly_delivered(struct sock *sk, u32 prior_delivered, int flag) +{ + const struct net *net = sock_net(sk); + struct tcp_sock *tp = tcp_sk(sk); + u32 delivered; + + delivered = tp->delivered - prior_delivered; + NET_ADD_STATS(net, LINUX_MIB_TCPDELIVERED, delivered); + if (flag & FLAG_ECE) { + tp->delivered_ce += delivered; + NET_ADD_STATS(net, LINUX_MIB_TCPDELIVEREDCE, delivered); + } + return delivered; +} + /* This routine deals with incoming acks, but not outgoing ones. */ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) { @@ -3545,6 +3613,12 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) if (after(ack, prior_snd_una)) { flag |= FLAG_SND_UNA_ADVANCED; icsk->icsk_retransmits = 0; + +#if IS_ENABLED(CONFIG_TLS_DEVICE) + if (static_branch_unlikely(&clean_acked_data_enabled)) + if (icsk->icsk_clean_acked) + icsk->icsk_clean_acked(sk, ack); +#endif } prior_fack = tcp_is_sack(tp) ? tcp_highest_sack_seq(tp) : tp->snd_una; @@ -3622,7 +3696,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP)) sk_dst_confirm(sk); - delivered = tp->delivered - delivered; /* freshly ACKed or SACKed */ + delivered = tcp_newly_delivered(sk, delivered, flag); lost = tp->lost - lost; /* freshly marked lost */ rs.is_ack_delayed = !!(flag & FLAG_ACK_MAYBE_DELAYED); tcp_rate_gen(sk, delivered, lost, is_sack_reneg, sack_state.rate); @@ -3632,9 +3706,11 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) no_queue: /* If data was DSACKed, see if we can undo a cwnd reduction. */ - if (flag & FLAG_DSACKING_ACK) + if (flag & FLAG_DSACKING_ACK) { tcp_fastretrans_alert(sk, prior_snd_una, is_dupack, &flag, &rexmit); + tcp_newly_delivered(sk, delivered, flag); + } /* If this ack opens up a zero window, clear backoff. It was * being used to time the probes, and is probably far higher than * it needs to be for normal retransmission. @@ -3658,6 +3734,7 @@ old_ack: &sack_state); tcp_fastretrans_alert(sk, prior_snd_una, is_dupack, &flag, &rexmit); + tcp_newly_delivered(sk, delivered, flag); tcp_xmit_recovery(sk, rexmit); } @@ -3871,11 +3948,8 @@ const u8 *tcp_parse_md5sig_option(const struct tcphdr *th) int length = (th->doff << 2) - sizeof(*th); const u8 *ptr = (const u8 *)(th + 1); - /* If the TCP option is too short, we can short cut */ - if (length < TCPOLEN_MD5SIG) - return NULL; - - while (length > 0) { + /* If not enough data remaining, we can short cut */ + while (length >= TCPOLEN_MD5SIG) { int opcode = *ptr++; int opsize; @@ -4132,7 +4206,7 @@ static void tcp_send_dupack(struct sock *sk, const struct sk_buff *skb) if (TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq && before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { NET_INC_STATS(sock_net(sk), LINUX_MIB_DELAYEDACKLOST); - tcp_enter_quickack_mode(sk); + tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); if (tcp_is_sack(tp) && sock_net(sk)->ipv4.sysctl_tcp_dsack) { u32 end_seq = TCP_SKB_CB(skb)->end_seq; @@ -4202,6 +4276,8 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq) * If the sack array is full, forget about the last one. */ if (this_sack >= TCP_NUM_SACKS) { + if (tp->compressed_ack) + tcp_send_ack(sk); this_sack--; tp->rx_opt.num_sacks--; sp--; @@ -4277,6 +4353,11 @@ static bool tcp_try_coalesce(struct sock *sk, if (TCP_SKB_CB(from)->seq != TCP_SKB_CB(to)->end_seq) return false; +#ifdef CONFIG_TLS_DEVICE + if (from->decrypted != to->decrypted) + return false; +#endif + if (!skb_try_coalesce(to, from, fragstolen, &delta)) return false; @@ -4295,6 +4376,23 @@ static bool tcp_try_coalesce(struct sock *sk, return true; } +static bool tcp_ooo_try_coalesce(struct sock *sk, + struct sk_buff *to, + struct sk_buff *from, + bool *fragstolen) +{ + bool res = tcp_try_coalesce(sk, to, from, fragstolen); + + /* In case tcp_drop() is called later, update to->gso_segs */ + if (res) { + u32 gso_segs = max_t(u16, 1, skb_shinfo(to)->gso_segs) + + max_t(u16, 1, skb_shinfo(from)->gso_segs); + + skb_shinfo(to)->gso_segs = min_t(u32, gso_segs, 0xFFFF); + } + return res; +} + static void tcp_drop(struct sock *sk, struct sk_buff *skb) { sk_drops_add(sk, skb); @@ -4383,7 +4481,7 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) u32 seq, end_seq; bool fragstolen; - tcp_ecn_check_ce(tp, skb); + tcp_ecn_check_ce(sk, skb); if (unlikely(tcp_try_rmem_schedule(sk, skb, skb->truesize))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFODROP); @@ -4418,8 +4516,8 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) /* In the typical case, we are adding an skb to the end of the list. * Use of ooo_last_skb avoids the O(Log(N)) rbtree lookup. */ - if (tcp_try_coalesce(sk, tp->ooo_last_skb, - skb, &fragstolen)) { + if (tcp_ooo_try_coalesce(sk, tp->ooo_last_skb, + skb, &fragstolen)) { coalesce_done: tcp_grow_window(sk, skb); kfree_skb_partial(skb, fragstolen); @@ -4447,7 +4545,7 @@ coalesce_done: /* All the bits are present. Drop. */ NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE); - __kfree_skb(skb); + tcp_drop(sk, skb); skb = NULL; tcp_dsack_set(sk, seq, end_seq); goto add_sack; @@ -4466,11 +4564,11 @@ coalesce_done: TCP_SKB_CB(skb1)->end_seq); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE); - __kfree_skb(skb1); + tcp_drop(sk, skb1); goto merge_right; } - } else if (tcp_try_coalesce(sk, skb1, - skb, &fragstolen)) { + } else if (tcp_ooo_try_coalesce(sk, skb1, + skb, &fragstolen)) { goto coalesce_done; } p = &parent->rb_right; @@ -4555,8 +4653,10 @@ int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size) skb->data_len = data_len; skb->len = size; - if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) + if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); goto err_free; + } err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size); if (err) @@ -4579,6 +4679,17 @@ err: } +void tcp_data_ready(struct sock *sk) +{ + const struct tcp_sock *tp = tcp_sk(sk); + int avail = tp->rcv_nxt - tp->copied_seq; + + if (avail < sk->sk_rcvlowat && !sock_flag(sk, SOCK_DONE)) + return; + + sk->sk_data_ready(sk); +} + static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) { struct tcp_sock *tp = tcp_sk(sk); @@ -4592,7 +4703,7 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) skb_dst_drop(skb); __skb_pull(skb, tcp_hdr(skb)->doff * 4); - tcp_ecn_accept_cwr(tp, skb); + tcp_ecn_accept_cwr(sk, skb); tp->rx_opt.dsack = 0; @@ -4601,18 +4712,21 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) * Out of sequence packets to the out_of_order_queue. */ if (TCP_SKB_CB(skb)->seq == tp->rcv_nxt) { - if (tcp_receive_window(tp) == 0) + if (tcp_receive_window(tp) == 0) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); goto out_of_window; + } /* Ok. In sequence. In window. */ queue_and_out: if (skb_queue_len(&sk->sk_receive_queue) == 0) sk_forced_mem_schedule(sk, skb->truesize); - else if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) + else if (tcp_try_rmem_schedule(sk, skb, skb->truesize)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVQDROP); goto drop; + } eaten = tcp_queue_rcv(sk, skb, 0, &fragstolen); - tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq); if (skb->len) tcp_event_data_recv(sk, skb); if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) @@ -4621,11 +4735,11 @@ queue_and_out: if (!RB_EMPTY_ROOT(&tp->out_of_order_queue)) { tcp_ofo_queue(sk); - /* RFC2581. 4.2. SHOULD send immediate ACK, when + /* RFC5681. 4.2. SHOULD send immediate ACK, when * gap in queue is filled. */ if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) - inet_csk(sk)->icsk_ack.pingpong = 0; + inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW; } if (tp->rx_opt.num_sacks) @@ -4636,7 +4750,7 @@ queue_and_out: if (eaten > 0) kfree_skb_partial(skb, fragstolen); if (!sock_flag(sk, SOCK_DEAD)) - sk->sk_data_ready(sk); + tcp_data_ready(sk); return; } @@ -4646,7 +4760,7 @@ queue_and_out: tcp_dsack_set(sk, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq); out_of_window: - tcp_enter_quickack_mode(sk); + tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); inet_csk_schedule_ack(sk); drop: tcp_drop(sk, skb); @@ -4657,8 +4771,6 @@ drop: if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt + tcp_receive_window(tp))) goto out_of_window; - tcp_enter_quickack_mode(sk); - if (before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { /* Partial packet, seq < rcv_next < end_seq */ SOCK_DEBUG(sk, "partial packet: rcv_next %X seq %X - %X\n", @@ -4670,8 +4782,10 @@ drop: /* If window is closed, drop tail of packet. But after * remembering D-SACK for its head made in previous line. */ - if (!tcp_receive_window(tp)) + if (!tcp_receive_window(tp)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPZEROWINDOWDROP); goto out_of_window; + } goto queue_and_out; } @@ -4789,6 +4903,9 @@ restart: break; memcpy(nskb->cb, skb->cb, sizeof(skb->cb)); +#ifdef CONFIG_TLS_DEVICE + nskb->decrypted = skb->decrypted; +#endif TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start; if (list) __skb_queue_before(list, skb, nskb); @@ -4816,6 +4933,10 @@ restart: skb == tail || (TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN))) goto end; +#ifdef CONFIG_TLS_DEVICE + if (skb->decrypted != nskb->decrypted) + goto end; +#endif } } } @@ -4830,6 +4951,7 @@ end: static void tcp_collapse_ofo_queue(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); + u32 range_truesize, sum_tiny = 0; struct sk_buff *skb, *head; u32 start, end; @@ -4841,6 +4963,7 @@ new_range: } start = TCP_SKB_CB(skb)->seq; end = TCP_SKB_CB(skb)->end_seq; + range_truesize = skb->truesize; for (head = skb;;) { skb = skb_rb_next(skb); @@ -4851,11 +4974,20 @@ new_range: if (!skb || after(TCP_SKB_CB(skb)->seq, end) || before(TCP_SKB_CB(skb)->end_seq, start)) { - tcp_collapse(sk, NULL, &tp->out_of_order_queue, - head, skb, start, end); + /* Do not attempt collapsing tiny skbs */ + if (range_truesize != head->truesize || + end - start >= SKB_WITH_OVERHEAD(SK_MEM_QUANTUM)) { + tcp_collapse(sk, NULL, &tp->out_of_order_queue, + head, skb, start, end); + } else { + sum_tiny += range_truesize; + if (sum_tiny > sk->sk_rcvbuf >> 3) + return; + } goto new_range; } + range_truesize += skb->truesize; if (unlikely(before(TCP_SKB_CB(skb)->seq, start))) start = TCP_SKB_CB(skb)->seq; if (after(TCP_SKB_CB(skb)->end_seq, end)) @@ -4870,6 +5002,7 @@ new_range: * 2) not add too big latencies if thousands of packets sit there. * (But if application shrinks SO_RCVBUF, we could still end up * freeing whole queue here) + * 3) Drop at least 12.5 % of sk_rcvbuf to avoid malicious attacks. * * Return true if queue has shrunk. */ @@ -4877,20 +5010,26 @@ static bool tcp_prune_ofo_queue(struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); struct rb_node *node, *prev; + int goal; if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) return false; NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED); + goal = sk->sk_rcvbuf >> 3; node = &tp->ooo_last_skb->rbnode; do { prev = rb_prev(node); rb_erase(node, &tp->out_of_order_queue); + goal -= rb_to_skb(node)->truesize; tcp_drop(sk, rb_to_skb(node)); - sk_mem_reclaim(sk); - if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && - !tcp_under_memory_pressure(sk)) - break; + if (!prev || goal <= 0) { + sk_mem_reclaim(sk); + if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && + !tcp_under_memory_pressure(sk)) + break; + goal = sk->sk_rcvbuf >> 3; + } node = prev; } while (node); tp->ooo_last_skb = rb_to_skb(prev); @@ -4925,6 +5064,9 @@ static int tcp_prune_queue(struct sock *sk) else if (tcp_under_memory_pressure(sk)) tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss); + if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) + return 0; + tcp_collapse_ofo_queue(sk); if (!skb_queue_empty(&sk->sk_receive_queue)) tcp_collapse(sk, &sk->sk_receive_queue, NULL, @@ -5025,23 +5167,50 @@ static inline void tcp_data_snd_check(struct sock *sk) static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible) { struct tcp_sock *tp = tcp_sk(sk); + unsigned long rtt, delay; /* More than one full frame received... */ if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss && /* ... and right edge of window advances far enough. - * (tcp_recvmsg() will send ACK otherwise). Or... + * (tcp_recvmsg() will send ACK otherwise). + * If application uses SO_RCVLOWAT, we want send ack now if + * we have not received enough bytes to satisfy the condition. */ - __tcp_select_window(sk) >= tp->rcv_wnd) || + (tp->rcv_nxt - tp->copied_seq < sk->sk_rcvlowat || + __tcp_select_window(sk) >= tp->rcv_wnd)) || /* We ACK each frame or... */ tcp_in_quickack_mode(sk) || - /* We have out of order data. */ - (ofo_possible && !RB_EMPTY_ROOT(&tp->out_of_order_queue))) { - /* Then ack it now */ + /* Protocol state mandates a one-time immediate ACK */ + inet_csk(sk)->icsk_ack.pending & ICSK_ACK_NOW) { +send_now: tcp_send_ack(sk); - } else { - /* Else, send delayed ack. */ + return; + } + + if (!ofo_possible || RB_EMPTY_ROOT(&tp->out_of_order_queue)) { tcp_send_delayed_ack(sk); + return; } + + if (!tcp_is_sack(tp) || + tp->compressed_ack >= sock_net(sk)->ipv4.sysctl_tcp_comp_sack_nr) + goto send_now; + tp->compressed_ack++; + + if (hrtimer_is_queued(&tp->compressed_ack_timer)) + return; + + /* compress ack timer : 5 % of rtt, but no more than tcp_comp_sack_delay_ns */ + + rtt = tp->rcv_rtt_est.rtt_us; + if (tp->srtt_us && tp->srtt_us < rtt) + rtt = tp->srtt_us; + + delay = min_t(unsigned long, sock_net(sk)->ipv4.sysctl_tcp_comp_sack_delay_ns, + rtt * (NSEC_PER_USEC >> 3)/20); + sock_hold(sk); + hrtimer_start(&tp->compressed_ack_timer, ns_to_ktime(delay), + HRTIMER_MODE_REL_PINNED_SOFT); } static inline void tcp_ack_snd_check(struct sock *sk) @@ -5305,11 +5474,11 @@ discard: * the rest is checked inline. Fast processing is turned on in * tcp_data_queue when everything is OK. */ -void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, - const struct tcphdr *th) +void tcp_rcv_established(struct sock *sk, struct sk_buff *skb) { - unsigned int len = skb->len; + const struct tcphdr *th = (const struct tcphdr *)skb->data; struct tcp_sock *tp = tcp_sk(sk); + unsigned int len = skb->len; /* TCP congestion window tracking */ trace_tcp_probe(sk, skb); @@ -5388,6 +5557,11 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, tcp_ack(sk, skb, 0); __kfree_skb(skb); tcp_data_snd_check(sk); + /* When receiving pure ack in fast path, update + * last ts ecr directly instead of calling + * tcp_rcv_rtt_measure_ts() + */ + tp->rcv_rtt_last_tsecr = tp->rx_opt.rcv_tsecr; return; } else { /* Header too small */ TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS); @@ -5434,7 +5608,7 @@ void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, no_ack: if (eaten) kfree_skb_partial(skb, fragstolen); - sk->sk_data_ready(sk); + tcp_data_ready(sk); return; } } @@ -5489,6 +5663,7 @@ void tcp_finish_connect(struct sock *sk, struct sk_buff *skb) if (skb) { icsk->icsk_af_ops->sk_rx_dst_set(sk, skb); security_inet_conn_established(sk, skb); + sk_mark_napi_id(sk, skb); } tcp_init_transfer(sk, BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB); @@ -5556,9 +5731,12 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack, return true; } tp->syn_data_acked = tp->syn_data; - if (tp->syn_data_acked) - NET_INC_STATS(sock_net(sk), - LINUX_MIB_TCPFASTOPENACTIVE); + if (tp->syn_data_acked) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVE); + /* SYN-data is counted as two separate packets in tcp_ack() */ + if (tp->delivered > 1) + --tp->delivered; + } tcp_fastopen_add_skb(sk, synack); @@ -5704,7 +5882,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, * to stand against the temptation 8) --ANK */ inet_csk_schedule_ack(sk); - tcp_enter_quickack_mode(sk); + tcp_enter_quickack_mode(sk, TCP_MAX_QUICKACKS); inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, TCP_DELACK_MAX, TCP_RTO_MAX); @@ -5862,10 +6040,12 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) tp->rx_opt.saw_tstamp = 0; req = tp->fastopen_rsk; if (req) { + bool req_stolen; + WARN_ON_ONCE(sk->sk_state != TCP_SYN_RECV && sk->sk_state != TCP_FIN_WAIT1); - if (!tcp_check_req(sk, skb, req, true)) + if (!tcp_check_req(sk, skb, req, true, &req_stolen)) goto discard; } @@ -5888,6 +6068,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) } switch (sk->sk_state) { case TCP_SYN_RECV: + tp->delivered++; /* SYN-ACK delivery isn't tracked in tcp_ack */ if (!tp->srtt_us) tcp_synack_rtt_meas(sk, req); @@ -6186,8 +6367,8 @@ static bool tcp_syn_flood_action(const struct sock *sk, if (!queue->synflood_warned && net->ipv4.sysctl_tcp_syncookies != 2 && xchg(&queue->synflood_warned, 1) == 0) - pr_info("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n", - proto, ntohs(tcp_hdr(skb)->dest), msg); + net_info_ratelimited("%s: Possible SYN flooding on port %d. %s. Check SNMP counters.\n", + proto, ntohs(tcp_hdr(skb)->dest), msg); return want_cookie; } @@ -6311,6 +6492,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, tcp_rsk(req)->snt_isn = isn; tcp_rsk(req)->txhash = net_tx_rndhash(); tcp_openreq_init_rwin(req, sk, dst); + sk_rx_queue_set(req_to_sk(req), skb); if (!want_cookie) { tcp_reqsk_record_syn(sk, req, skb); fastopen_sk = tcp_try_fastopen(sk, skb, req, &foc, dst); |