1 files changed, 56 insertions, 148 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 9df64a50b075..f49476e2d884 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -277,22 +277,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
         rt = (struct rt6_info *) dst;
         if (tcp_death_row.sysctl_tw_recycle &&
             !tp->rx_opt.ts_recent_stamp &&
-            ipv6_addr_equal(&rt->rt6i_dst.addr, &np->daddr)) {
-                struct inet_peer *peer = rt6_get_peer(rt);
-                /*
-                 * VJ's idea. We save last timestamp seen from
-                 * the destination in peer table, when entering state
-                 * TIME-WAIT * and initialize rx_opt.ts_recent from it,
-                 * when trying new connection.
-                 */
-                if (peer) {
-                        inet_peer_refcheck(peer);
-                        if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) {
-                                tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp;
-                                tp->rx_opt.ts_recent = peer->tcp_ts;
-                        }
-                }
-        }
+            ipv6_addr_equal(&rt->rt6i_dst.addr, &np->daddr))
+                tcp_fetch_timewait_stamp(sk, dst);
 
         icsk->icsk_ext_hdr_len = 0;
         if (np->opt)
@@ -329,6 +315,23 @@ failure:
         return err;
 }
 
+static void tcp_v6_mtu_reduced(struct sock *sk)
+{
+        struct dst_entry *dst;
+
+        if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
+                return;
+
+        dst = inet6_csk_update_pmtu(sk, tcp_sk(sk)->mtu_info);
+        if (!dst)
+                return;
+
+        if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
+                tcp_sync_mss(sk, dst_mtu(dst));
+                tcp_simple_retransmit(sk);
+        }
+}
+
 static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
                 u8 type, u8 code, int offset, __be32 info)
 {
@@ -356,7 +359,7 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         }
 
         bh_lock_sock(sk);
-        if (sock_owned_by_user(sk))
+        if (sock_owned_by_user(sk) && type != ICMPV6_PKT_TOOBIG)
                 NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
 
         if (sk->sk_state == TCP_CLOSE)
@@ -377,49 +380,19 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 
         np = inet6_sk(sk);
 
-        if (type == ICMPV6_PKT_TOOBIG) {
-                struct dst_entry *dst;
-
-                if (sock_owned_by_user(sk))
-                        goto out;
-                if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
-                        goto out;
-
-                /* icmp should have updated the destination cache entry */
-                dst = __sk_dst_check(sk, np->dst_cookie);
-
-                if (dst == NULL) {
-                        struct inet_sock *inet = inet_sk(sk);
-                        struct flowi6 fl6;
-
-                        /* BUGGG_FUTURE: Again, it is not clear how
-                           to handle rthdr case. Ignore this complexity
-                           for now.
-                         */
-                        memset(&fl6, 0, sizeof(fl6));
-                        fl6.flowi6_proto = IPPROTO_TCP;
-                        fl6.daddr = np->daddr;
-                        fl6.saddr = np->saddr;
-                        fl6.flowi6_oif = sk->sk_bound_dev_if;
-                        fl6.flowi6_mark = sk->sk_mark;
-                        fl6.fl6_dport = inet->inet_dport;
-                        fl6.fl6_sport = inet->inet_sport;
-                        security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
-
-                        dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
-                        if (IS_ERR(dst)) {
-                                sk->sk_err_soft = -PTR_ERR(dst);
-                                goto out;
-                        }
+        if (type == NDISC_REDIRECT) {
+                struct dst_entry *dst = __sk_dst_check(sk, np->dst_cookie);
 
-                } else
-                        dst_hold(dst);
+                if (dst)
+                        dst->ops->redirect(dst, sk, skb);
+        }
 
-                if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
-                        tcp_sync_mss(sk, dst_mtu(dst));
-                        tcp_simple_retransmit(sk);
-                } /* else let the usual retransmit timer handle it */
-                dst_release(dst);
+        if (type == ICMPV6_PKT_TOOBIG) {
+                tp->mtu_info = ntohl(info);
+                if (!sock_owned_by_user(sk))
+                        tcp_v6_mtu_reduced(sk);
+                else
+                        set_bit(TCP_MTU_REDUCED_DEFERRED, &tp->tsq_flags);
                 goto out;
         }
 
@@ -475,62 +448,43 @@ out:
 }
 
 
-static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
+static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst,
+                              struct flowi6 *fl6,
+                              struct request_sock *req,
                               struct request_values *rvp,
                               u16 queue_mapping)
 {
         struct inet6_request_sock *treq = inet6_rsk(req);
         struct ipv6_pinfo *np = inet6_sk(sk);
         struct sk_buff * skb;
-        struct ipv6_txoptions *opt = NULL;
-        struct in6_addr * final_p, final;
-        struct flowi6 fl6;
-        struct dst_entry *dst;
-        int err;
+        int err = -ENOMEM;
 
-        memset(&fl6, 0, sizeof(fl6));
-        fl6.flowi6_proto = IPPROTO_TCP;
-        fl6.daddr = treq->rmt_addr;
-        fl6.saddr = treq->loc_addr;
-        fl6.flowlabel = 0;
-        fl6.flowi6_oif = treq->iif;
-        fl6.flowi6_mark = sk->sk_mark;
-        fl6.fl6_dport = inet_rsk(req)->rmt_port;
-        fl6.fl6_sport = inet_rsk(req)->loc_port;
-        security_req_classify_flow(req, flowi6_to_flowi(&fl6));
-
-        opt = np->opt;
-        final_p = fl6_update_dst(&fl6, opt, &final);
-
-        dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
-        if (IS_ERR(dst)) {
-                err = PTR_ERR(dst);
-                dst = NULL;
+        /* First, grab a route. */
+        if (!dst && (dst = inet6_csk_route_req(sk, fl6, req)) == NULL)
                 goto done;
-        }
+
         skb = tcp_make_synack(sk, dst, req, rvp);
-        err = -ENOMEM;
+
         if (skb) {
                 __tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
 
-                fl6.daddr = treq->rmt_addr;
+                fl6->daddr = treq->rmt_addr;
                 skb_set_queue_mapping(skb, queue_mapping);
-                err = ip6_xmit(sk, skb, &fl6, opt, np->tclass);
+                err = ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
                 err = net_xmit_eval(err);
         }
 
 done:
-        if (opt && opt != np->opt)
-                sock_kfree_s(sk, opt, opt->tot_len);
-        dst_release(dst);
         return err;
 }
 
 static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req,
                              struct request_values *rvp)
 {
+        struct flowi6 fl6;
+
         TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
-        return tcp_v6_send_synack(sk, req, rvp, 0);
+        return tcp_v6_send_synack(sk, NULL, &fl6, req, rvp, 0);
 }
 
 static void tcp_v6_reqsk_destructor(struct request_sock *req)
@@ -1057,6 +1011,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         struct tcp_sock *tp = tcp_sk(sk);
         __u32 isn = TCP_SKB_CB(skb)->when;
         struct dst_entry *dst = NULL;
+        struct flowi6 fl6;
         bool want_cookie = false;
 
         if (skb->protocol == htons(ETH_P_IP))
@@ -1085,7 +1040,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         tcp_clear_options(&tmp_opt);
         tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
         tmp_opt.user_mss = tp->rx_opt.user_mss;
-        tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
+        tcp_parse_options(skb, &tmp_opt, &hash_location, 0, NULL);
 
         if (tmp_opt.cookie_plus > 0 &&
             tmp_opt.saw_tstamp &&
@@ -1150,8 +1105,6 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
                 treq->iif = inet6_iif(skb);
 
         if (!isn) {
-                struct inet_peer *peer = NULL;
-
                 if (ipv6_opt_accepted(sk, skb) ||
                     np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
                     np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
@@ -1176,14 +1129,8 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
                  */
                 if (tmp_opt.saw_tstamp &&
                     tcp_death_row.sysctl_tw_recycle &&
-                    (dst = inet6_csk_route_req(sk, req)) != NULL &&
-                    (peer = rt6_get_peer((struct rt6_info *)dst)) != NULL &&
-                    ipv6_addr_equal((struct in6_addr *)peer->daddr.addr.a6,
-                                    &treq->rmt_addr)) {
-                        inet_peer_refcheck(peer);
-                        if ((u32)get_seconds() - peer->tcp_ts_stamp < TCP_PAWS_MSL &&
-                            (s32)(peer->tcp_ts - req->ts_recent) >
-                                                        TCP_PAWS_WINDOW) {
+                    (dst = inet6_csk_route_req(sk, &fl6, req)) != NULL) {
+                        if (!tcp_peer_is_proven(req, dst, true)) {
                                 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
                                 goto drop_and_release;
                         }
@@ -1192,8 +1139,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
                 else if (!sysctl_tcp_syncookies &&
                          (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) <
                           (sysctl_max_syn_backlog >> 2)) &&
-                         (!peer || !peer->tcp_ts_stamp) &&
-                         (!dst || !dst_metric(dst, RTAX_RTT))) {
+                         !tcp_peer_is_proven(req, dst, false)) {
                         /* Without syncookies last quarter of
                          * backlog is filled with destinations,
                          * proven to be alive.
@@ -1215,7 +1161,7 @@ have_isn:
         if (security_inet_conn_request(sk, skb, req))
                 goto drop_and_release;
 
-        if (tcp_v6_send_synack(sk, req,
+        if (tcp_v6_send_synack(sk, dst, &fl6, req,
                                (struct request_values *)&tmp_ext,
                                skb_get_queue_mapping(skb)) ||
             want_cookie)
@@ -1242,10 +1188,10 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         struct inet_sock *newinet;
         struct tcp_sock *newtp;
         struct sock *newsk;
-        struct ipv6_txoptions *opt;
 #ifdef CONFIG_TCP_MD5SIG
         struct tcp_md5sig_key *key;
 #endif
+        struct flowi6 fl6;
 
         if (skb->protocol == htons(ETH_P_IP)) {
                 /*
@@ -1302,13 +1248,12 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         }
 
         treq = inet6_rsk(req);
-        opt = np->opt;
 
         if (sk_acceptq_is_full(sk))
                 goto out_overflow;
 
         if (!dst) {
-                dst = inet6_csk_route_req(sk, req);
+                dst = inet6_csk_route_req(sk, &fl6, req);
                 if (!dst)
                         goto out;
         }
@@ -1371,11 +1316,8 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
            but we make one more one thing there: reattach optmem
            to newsk.
          */
-        if (opt) {
-                newnp->opt = ipv6_dup_options(newsk, opt);
-                if (opt != np->opt)
-                        sock_kfree_s(sk, opt, opt->tot_len);
-        }
+        if (np->opt)
+                newnp->opt = ipv6_dup_options(newsk, np->opt);
 
         inet_csk(newsk)->icsk_ext_hdr_len = 0;
         if (newnp->opt)
@@ -1422,8 +1364,6 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 out_overflow:
         NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
 out_nonewsk:
-        if (opt && opt != np->opt)
-                sock_kfree_s(sk, opt, opt->tot_len);
         dst_release(dst);
 out:
         NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
@@ -1734,42 +1674,10 @@ do_time_wait:
         goto discard_it;
 }
 
-static struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
-{
-        struct rt6_info *rt = (struct rt6_info *) __sk_dst_get(sk);
-        struct ipv6_pinfo *np = inet6_sk(sk);
-        struct inet_peer *peer;
-
-        if (!rt ||
-            !ipv6_addr_equal(&np->daddr, &rt->rt6i_dst.addr)) {
-                peer = inet_getpeer_v6(&np->daddr, 1);
-                *release_it = true;
-        } else {
-                if (!rt->rt6i_peer)
-                        rt6_bind_peer(rt, 1);
-                peer = rt->rt6i_peer;
-                *release_it = false;
-        }
-
-        return peer;
-}
-
-static void *tcp_v6_tw_get_peer(struct sock *sk)
-{
-        const struct inet6_timewait_sock *tw6 = inet6_twsk(sk);
-        const struct inet_timewait_sock *tw = inet_twsk(sk);
-
-        if (tw->tw_family == AF_INET)
-                return tcp_v4_tw_get_peer(sk);
-
-        return inet_getpeer_v6(&tw6->tw_v6_daddr, 1);
-}
-
 static struct timewait_sock_ops tcp6_timewait_sock_ops = {
         .twsk_obj_size  = sizeof(struct tcp6_timewait_sock),
         .twsk_unique    = tcp_twsk_unique,
         .twsk_destructor= tcp_twsk_destructor,
-        .twsk_getpeer   = tcp_v6_tw_get_peer,
 };
 
 static const struct inet_connection_sock_af_ops ipv6_specific = {
@@ -1778,7 +1686,6 @@ static const struct inet_connection_sock_af_ops ipv6_specific = {
         .rebuild_header    = inet6_sk_rebuild_header,
         .conn_request      = tcp_v6_conn_request,
         .syn_recv_sock     = tcp_v6_syn_recv_sock,
-        .get_peer          = tcp_v6_get_peer,
         .net_header_len    = sizeof(struct ipv6hdr),
         .net_frag_header_len = sizeof(struct frag_hdr),
         .setsockopt        = ipv6_setsockopt,
@@ -1810,7 +1717,6 @@ static const struct inet_connection_sock_af_ops ipv6_mapped = {
         .rebuild_header    = inet_sk_rebuild_header,
         .conn_request      = tcp_v6_conn_request,
         .syn_recv_sock     = tcp_v6_syn_recv_sock,
-        .get_peer          = tcp_v4_get_peer,
         .net_header_len    = sizeof(struct iphdr),
         .setsockopt        = ipv6_setsockopt,
         .getsockopt        = ipv6_getsockopt,
@@ -2049,6 +1955,8 @@ struct proto tcpv6_prot = {
         .sendmsg                = tcp_sendmsg,
         .sendpage               = tcp_sendpage,
         .backlog_rcv            = tcp_v6_do_rcv,
+        .release_cb             = tcp_release_cb,
+        .mtu_reduced            = tcp_v6_mtu_reduced,
         .hash                   = tcp_v6_hash,
         .unhash                 = inet_unhash,
         .get_port               = inet_csk_get_port,