tcp: connect() race with timewait reuse

[firefly-linux-kernel-4.4.55.git] / net / ipv6 / inet6_hashtables.c

diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 1bcc3431859ede58e1166a9efaa101461e1cc8e6..c813e294ec0c94d2aac13149f528683a85987d91 100644 (file)
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -73,7 +73,7 @@ struct sock *__inet6_lookup_established(struct net *net,
         * have wildcards anyways.
         */
        unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
-       unsigned int slot = hash & (hashinfo->ehash_size - 1);
+       unsigned int slot = hash & hashinfo->ehash_mask;
        struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 
 
@@ -125,7 +125,7 @@ static int inline compute_score(struct sock *sk, struct net *net,
 {
        int score = -1;
 
-       if (net_eq(sock_net(sk), net) && inet_sk(sk)->num == hnum &&
+       if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
            sk->sk_family == PF_INET6) {
                const struct ipv6_pinfo *np = inet6_sk(sk);
 
@@ -214,15 +214,16 @@ static int __inet6_check_established(struct inet_timewait_death_row *death_row,
        const struct in6_addr *daddr = &np->rcv_saddr;
        const struct in6_addr *saddr = &np->daddr;
        const int dif = sk->sk_bound_dev_if;
-       const __portpair ports = INET_COMBINED_PORTS(inet->dport, lport);
+       const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
        struct net *net = sock_net(sk);
        const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
-                                               inet->dport);
+                                               inet->inet_dport);
        struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
        spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
        struct sock *sk2;
        const struct hlist_nulls_node *node;
        struct inet_timewait_sock *tw;
+       int twrefcnt = 0;
 
        spin_lock(lock);
 
@@ -248,21 +249,25 @@ static int __inet6_check_established(struct inet_timewait_death_row *death_row,
 unique:
        /* Must record num and sport now. Otherwise we will see
         * in hash table socket with a funny identity. */
-       inet->num = lport;
-       inet->sport = htons(lport);
+       inet->inet_num = lport;
+       inet->inet_sport = htons(lport);
+       sk->sk_hash = hash;
        WARN_ON(!sk_unhashed(sk));
        __sk_nulls_add_node_rcu(sk, &head->chain);
-       sk->sk_hash = hash;
+       if (tw) {
+               twrefcnt = inet_twsk_unhash(tw);
+               NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED);
+       }
        spin_unlock(lock);
+       if (twrefcnt)
+               inet_twsk_put(tw);
        sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
 
-       if (twp != NULL) {
+       if (twp) {
                *twp = tw;
-               NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED);
-       } else if (tw != NULL) {
+       } else if (tw) {
                /* Silly. Should hash-dance instead... */
                inet_twsk_deschedule(tw, death_row);
-               NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED);
 
                inet_twsk_put(tw);
        }
@@ -279,7 +284,7 @@ static inline u32 inet6_sk_port_offset(const struct sock *sk)
        const struct ipv6_pinfo *np = inet6_sk(sk);
        return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
                                          np->daddr.s6_addr32,
-                                         inet->dport);
+                                         inet->inet_dport);
 }
 
 int inet6_hash_connect(struct inet_timewait_death_row *death_row,