Merge mainline/master into arm/fixes

[linux.git] / net / ipv4 / tcp_ipv4.c

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index bf124b1742df864a3007d137ff31c8bfb2bee12a..92282f98dc82290bfaf53acc050182e4cc3be1eb 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -121,11 +121,9 @@ int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
 #if IS_ENABLED(CONFIG_IPV6)
                if (tw->tw_family == AF_INET6) {
                        if (ipv6_addr_loopback(&tw->tw_v6_daddr) ||
-                           (ipv6_addr_v4mapped(&tw->tw_v6_daddr) &&
-                            (tw->tw_v6_daddr.s6_addr[12] == 127)) ||
+                           ipv6_addr_v4mapped_loopback(&tw->tw_v6_daddr) ||
                            ipv6_addr_loopback(&tw->tw_v6_rcv_saddr) ||
-                           (ipv6_addr_v4mapped(&tw->tw_v6_rcv_saddr) &&
-                            (tw->tw_v6_rcv_saddr.s6_addr[12] == 127)))
+                           ipv6_addr_v4mapped_loopback(&tw->tw_v6_rcv_saddr))
                                loopback = true;
                } else
 #endif
@@ -164,9 +162,11 @@ int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
                 * without appearing to create any others.
                 */
                if (likely(!tp->repair)) {
-                       tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2;
-                       if (tp->write_seq == 0)
-                               tp->write_seq = 1;
+                       u32 seq = tcptw->tw_snd_nxt + 65535 + 2;
+
+                       if (!seq)
+                               seq = 1;
+                       WRITE_ONCE(tp->write_seq, seq);
                        tp->rx_opt.ts_recent       = tcptw->tw_ts_recent;
                        tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
                }
@@ -253,7 +253,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
                tp->rx_opt.ts_recent       = 0;
                tp->rx_opt.ts_recent_stamp = 0;
                if (likely(!tp->repair))
-                       tp->write_seq      = 0;
+                       WRITE_ONCE(tp->write_seq, 0);
        }
 
        inet->inet_dport = usin->sin_port;
@@ -291,16 +291,17 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 
        if (likely(!tp->repair)) {
                if (!tp->write_seq)
-                       tp->write_seq = secure_tcp_seq(inet->inet_saddr,
-                                                      inet->inet_daddr,
-                                                      inet->inet_sport,
-                                                      usin->sin_port);
+                       WRITE_ONCE(tp->write_seq,
+                                  secure_tcp_seq(inet->inet_saddr,
+                                                 inet->inet_daddr,
+                                                 inet->inet_sport,
+                                                 usin->sin_port));
                tp->tsoffset = secure_tcp_ts_off(sock_net(sk),
                                                 inet->inet_saddr,
                                                 inet->inet_daddr);
        }
 
-       inet->inet_id = tp->write_seq ^ jiffies;
+       inet->inet_id = prandom_u32();
 
        if (tcp_fastopen_defer_connect(sk, &err))
                return err;
@@ -478,7 +479,7 @@ int tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
        icsk = inet_csk(sk);
        tp = tcp_sk(sk);
        /* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
-       fastopen = tp->fastopen_rsk;
+       fastopen = rcu_dereference(tp->fastopen_rsk);
        snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
        if (sk->sk_state != TCP_LISTEN &&
            !between(seq, snd_una, tp->snd_nxt)) {
@@ -1447,7 +1448,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
        inet_csk(newsk)->icsk_ext_hdr_len = 0;
        if (inet_opt)
                inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
-       newinet->inet_id = newtp->write_seq ^ jiffies;
+       newinet->inet_id = prandom_u32();
 
        if (!dst) {
                dst = inet_csk_route_child_sock(sk, newsk, req);
@@ -1644,7 +1645,7 @@ int tcp_v4_early_demux(struct sk_buff *skb)
 
 bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb)
 {
-       u32 limit = sk->sk_rcvbuf + sk->sk_sndbuf;
+       u32 limit = READ_ONCE(sk->sk_rcvbuf) + READ_ONCE(sk->sk_sndbuf);
        struct skb_shared_info *shinfo;
        const struct tcphdr *th;
        struct tcphdr *thtail;
@@ -2121,7 +2122,7 @@ void tcp_v4_destroy_sock(struct sock *sk)
        if (inet_csk(sk)->icsk_bind_hash)
                inet_put_port(sk);
 
-       BUG_ON(tp->fastopen_rsk);
+       BUG_ON(rcu_access_pointer(tp->fastopen_rsk));
 
        /* If socket is aborted during connect operation */
        tcp_free_fastopen_req(tp);
@@ -2450,17 +2451,18 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
 
        state = inet_sk_state_load(sk);
        if (state == TCP_LISTEN)
-               rx_queue = sk->sk_ack_backlog;
+               rx_queue = READ_ONCE(sk->sk_ack_backlog);
        else
                /* Because we don't lock the socket,
                 * we might find a transient negative value.
                 */
-               rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
+               rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) -
+                                     READ_ONCE(tp->copied_seq), 0);
 
        seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX "
                        "%08X %5u %8d %lu %d %pK %lu %lu %u %u %d",
                i, src, srcp, dest, destp, state,
-               tp->write_seq - tp->snd_una,
+               READ_ONCE(tp->write_seq) - tp->snd_una,
                rx_queue,
                timer_active,
                jiffies_delta_to_clock_t(timer_expires - jiffies),
@@ -2677,7 +2679,7 @@ static int __net_init tcp_sk_init(struct net *net)
        net->ipv4.tcp_death_row.sysctl_max_tw_buckets = cnt / 2;
        net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo;
 
-       net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256);
+       net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 128);
        net->ipv4.sysctl_tcp_sack = 1;
        net->ipv4.sysctl_tcp_window_scaling = 1;
        net->ipv4.sysctl_tcp_timestamps = 1;