--- zzzz-none-000/linux-3.10.107/net/dccp/minisocks.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/net/dccp/minisocks.c 2021-02-04 17:41:59.000000000 +0000 @@ -27,46 +27,27 @@ struct inet_timewait_death_row dccp_death_row = { .sysctl_max_tw_buckets = NR_FILE * 2, - .period = DCCP_TIMEWAIT_LEN / INET_TWDR_TWKILL_SLOTS, - .death_lock = __SPIN_LOCK_UNLOCKED(dccp_death_row.death_lock), .hashinfo = &dccp_hashinfo, - .tw_timer = TIMER_INITIALIZER(inet_twdr_hangman, 0, - (unsigned long)&dccp_death_row), - .twkill_work = __WORK_INITIALIZER(dccp_death_row.twkill_work, - inet_twdr_twkill_work), -/* Short-time timewait calendar */ - - .twcal_hand = -1, - .twcal_timer = TIMER_INITIALIZER(inet_twdr_twcal_tick, 0, - (unsigned long)&dccp_death_row), }; EXPORT_SYMBOL_GPL(dccp_death_row); void dccp_time_wait(struct sock *sk, int state, int timeo) { - struct inet_timewait_sock *tw = NULL; + struct inet_timewait_sock *tw; - if (dccp_death_row.tw_count < dccp_death_row.sysctl_max_tw_buckets) - tw = inet_twsk_alloc(sk, state); + tw = inet_twsk_alloc(sk, &dccp_death_row, state); if (tw != NULL) { const struct inet_connection_sock *icsk = inet_csk(sk); const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1); #if IS_ENABLED(CONFIG_IPV6) if (tw->tw_family == PF_INET6) { - const struct ipv6_pinfo *np = inet6_sk(sk); - struct inet6_timewait_sock *tw6; - - tw->tw_ipv6_offset = inet6_tw_offset(sk->sk_prot); - tw6 = inet6_twsk((struct sock *)tw); - tw6->tw_v6_daddr = np->daddr; - tw6->tw_v6_rcv_saddr = np->rcv_saddr; - tw->tw_ipv6only = np->ipv6only; + tw->tw_v6_daddr = sk->sk_v6_daddr; + tw->tw_v6_rcv_saddr = sk->sk_v6_rcv_saddr; + tw->tw_ipv6only = sk->sk_ipv6only; } #endif - /* Linkage updates. */ - __inet_twsk_hashdance(tw, sk, &dccp_hashinfo); /* Get the TIME_WAIT timeout firing. */ if (timeo < rto) @@ -76,8 +57,9 @@ if (state == DCCP_TIME_WAIT) timeo = DCCP_TIMEWAIT_LEN; - inet_twsk_schedule(tw, &dccp_death_row, timeo, - DCCP_TIMEWAIT_LEN); + inet_twsk_schedule(tw, timeo); + /* Linkage updates. */ + __inet_twsk_hashdance(tw, sk, &dccp_hashinfo); inet_twsk_put(tw); } else { /* Sorry, if we're out of memory, just CLOSE this @@ -90,7 +72,7 @@ dccp_done(sk); } -struct sock *dccp_create_openreq_child(struct sock *sk, +struct sock *dccp_create_openreq_child(const struct sock *sk, const struct request_sock *req, const struct sk_buff *skb) { @@ -158,11 +140,18 @@ * as an request_sock. */ struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb, - struct request_sock *req, - struct request_sock **prev) + struct request_sock *req) { struct sock *child = NULL; struct dccp_request_sock *dreq = dccp_rsk(req); + bool own_req; + + /* TCP/DCCP listeners became lockless. + * DCCP stores complex state in its request_sock, so we need + * a protection for them, now this code runs without being protected + * by the parent (listener) lock. + */ + spin_lock_bh(&dreq->dreq_lock); /* Check for retransmitted REQUEST */ if (dccp_hdr(skb)->dccph_type == DCCP_PKT_REQUEST) { @@ -178,7 +167,7 @@ inet_rtx_syn_ack(sk, req); } /* Network Duplicate, discard packet */ - return NULL; + goto out; } DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR; @@ -202,24 +191,22 @@ if (dccp_parse_options(sk, dreq, skb)) goto drop; - child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL); - if (child == NULL) - goto listen_overflow; - - inet_csk_reqsk_queue_unlink(sk, req, prev); - inet_csk_reqsk_queue_removed(sk, req); - inet_csk_reqsk_queue_add(sk, req, child); -out: - return child; -listen_overflow: - dccp_pr_debug("listen_overflow!\n"); + child = inet_csk(sk)->icsk_af_ops->syn_recv_sock(sk, skb, req, NULL, + req, &own_req); + if (child) { + child = inet_csk_complete_hashdance(sk, child, req, own_req); + goto out; + } + DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_TOO_BUSY; drop: if (dccp_hdr(skb)->dccph_type != DCCP_PKT_RESET) req->rsk_ops->send_reset(sk, skb); - inet_csk_reqsk_queue_drop(sk, req, prev); - goto out; + inet_csk_reqsk_queue_drop(sk, req); +out: + spin_unlock_bh(&dreq->dreq_lock); + return child; } EXPORT_SYMBOL_GPL(dccp_check_req); @@ -241,7 +228,7 @@ /* Wakeup parent, send SIGIO */ if (state == DCCP_RESPOND && child->sk_state != state) - parent->sk_data_ready(parent, 0); + parent->sk_data_ready(parent); } else { /* Alas, it is possible again, because we do lookup * in main socket hash table and lock on listening @@ -257,7 +244,7 @@ EXPORT_SYMBOL_GPL(dccp_child_process); -void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb, +void dccp_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, struct request_sock *rsk) { DCCP_BUG("DCCP-ACK packets are never sent in LISTEN/RESPOND state"); @@ -270,10 +257,11 @@ { struct dccp_request_sock *dreq = dccp_rsk(req); - inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport; - inet_rsk(req)->loc_port = dccp_hdr(skb)->dccph_dport; - inet_rsk(req)->acked = 0; - dreq->dreq_timestamp_echo = 0; + spin_lock_init(&dreq->dreq_lock); + inet_rsk(req)->ir_rmt_port = dccp_hdr(skb)->dccph_sport; + inet_rsk(req)->ir_num = ntohs(dccp_hdr(skb)->dccph_dport); + inet_rsk(req)->acked = 0; + dreq->dreq_timestamp_echo = 0; /* inherit feature negotiation options from listening socket */ return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);