diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/udp.c | 73 | ||||
| -rw-r--r-- | net/ipv6/udp.c | 14 |
2 files changed, 72 insertions, 15 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index d73e917..1eaf575 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -152,16 +152,49 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num, return 0; } +/* + * Note: we still hold spinlock of primary hash chain, so no other writer + * can insert/delete a socket with local_port == num + */ +static int udp_lib_lport_inuse2(struct net *net, __u16 num, + struct udp_hslot *hslot2, + struct sock *sk, + int (*saddr_comp)(const struct sock *sk1, + const struct sock *sk2)) +{ + struct sock *sk2; + struct hlist_nulls_node *node; + int res = 0; + + spin_lock(&hslot2->lock); + udp_portaddr_for_each_entry(sk2, node, &hslot2->head) + if (net_eq(sock_net(sk2), net) && + sk2 != sk && + (udp_sk(sk2)->udp_port_hash == num) && + (!sk2->sk_reuse || !sk->sk_reuse) && + (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if + || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && + (*saddr_comp)(sk, sk2)) { + res = 1; + break; + } + spin_unlock(&hslot2->lock); + return res; +} + /** * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6 * * @sk: socket struct in question * @snum: port number to look up * @saddr_comp: AF-dependent comparison of bound local IP addresses + * @hash2_nulladdr: AF-dependant hash value in secondary hash chains, + * with NULL address */ int udp_lib_get_port(struct sock *sk, unsigned short snum, int (*saddr_comp)(const struct sock *sk1, - const struct sock *sk2)) + const struct sock *sk2), + unsigned int hash2_nulladdr) { struct udp_hslot *hslot, *hslot2; struct udp_table *udptable = sk->sk_prot->h.udp_table; @@ -210,6 +243,30 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum, } else { hslot = udp_hashslot(udptable, net, snum); spin_lock_bh(&hslot->lock); + if (hslot->count > 10) { + int exist; + unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum; + + slot2 &= udptable->mask; + hash2_nulladdr &= udptable->mask; + + hslot2 = udp_hashslot2(udptable, slot2); + if (hslot->count < hslot2->count) + goto scan_primary_hash; + + exist = udp_lib_lport_inuse2(net, snum, hslot2, + sk, saddr_comp); + if (!exist && (hash2_nulladdr != slot2)) { + hslot2 = udp_hashslot2(udptable, hash2_nulladdr); + exist = udp_lib_lport_inuse2(net, snum, hslot2, + sk, saddr_comp); + } + if (exist) + goto fail_unlock; + else + goto found; + } +scan_primary_hash: if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, saddr_comp, 0)) goto fail_unlock; @@ -255,12 +312,14 @@ static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr, int udp_v4_get_port(struct sock *sk, unsigned short snum) { + unsigned int hash2_nulladdr = + udp4_portaddr_hash(sock_net(sk), INADDR_ANY, snum); + unsigned int hash2_partial = + udp4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0); + /* precompute partial secondary hash */ - udp_sk(sk)->udp_portaddr_hash = - udp4_portaddr_hash(sock_net(sk), - inet_sk(sk)->inet_rcv_saddr, - 0); - return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal); + udp_sk(sk)->udp_portaddr_hash = hash2_partial; + return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr); } static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr, @@ -336,8 +395,6 @@ static inline int compute_score2(struct sock *sk, struct net *net, return score; } -#define udp_portaddr_for_each_entry_rcu(__sk, node, list) \ - hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node) /* called with read_rcu_lock() */ static struct sock *udp4_lib_lookup2(struct net *net, diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 2915e1d..f4c85b2 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -100,12 +100,14 @@ static unsigned int udp6_portaddr_hash(struct net *net, int udp_v6_get_port(struct sock *sk, unsigned short snum) { + unsigned int hash2_nulladdr = + udp6_portaddr_hash(sock_net(sk), &in6addr_any, snum); + unsigned int hash2_partial = + udp6_portaddr_hash(sock_net(sk), &inet6_sk(sk)->rcv_saddr, 0); + /* precompute partial secondary hash */ - udp_sk(sk)->udp_portaddr_hash = - udp6_portaddr_hash(sock_net(sk), - &inet6_sk(sk)->rcv_saddr, - 0); - return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal); + udp_sk(sk)->udp_portaddr_hash = hash2_partial; + return udp_lib_get_port(sk, snum, ipv6_rcv_saddr_equal, hash2_nulladdr); } static inline int compute_score(struct sock *sk, struct net *net, @@ -181,8 +183,6 @@ static inline int compute_score2(struct sock *sk, struct net *net, return score; } -#define udp_portaddr_for_each_entry_rcu(__sk, node, list) \ - hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node) /* called with read_rcu_lock() */ static struct sock *udp6_lib_lookup2(struct net *net, |