From aacd9289af8b82f5fb01bcdd53d0e3406d1333c7 Mon Sep 17 00:00:00 2001 From: Alex Copot Date: Thu, 12 Apr 2012 22:21:45 +0000 Subject: [PATCH] tcp: bind() use stronger condition for bind_conflict We must try harder to get unique (addr, port) pairs when doing port autoselection for sockets with SO_REUSEADDR option set. We achieve this by adding a relaxation parameter to inet_csk_bind_conflict. When 'relax' parameter is off we return a conflict whenever the current searched pair (addr, port) is not unique. This tries to address the problems reported in patch: 8d238b25b1ec22a73b1c2206f111df2faaff8285 Revert "tcp: bind() fix when many ports are bound" Tests where ran for creating and binding(0) many sockets on 100 IPs. The results are, on average: * 60000 sockets, 600 ports / IP: * 0.210 s, 620 (IP, port) duplicates without patch * 0.219 s, no duplicates with patch * 100000 sockets, 1000 ports / IP: * 0.371 s, 1720 duplicates without patch * 0.373 s, no duplicates with patch * 200000 sockets, 2000 ports / IP: * 0.766 s, 6900 duplicates without patch * 0.768 s, no duplicates with patch * 500000 sockets, 5000 ports / IP: * 2.227 s, 41500 duplicates without patch * 2.284 s, no duplicates with patch Signed-off-by: Alex Copot Signed-off-by: Daniel Baluta Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/inet6_connection_sock.h | 2 +- include/net/inet_connection_sock.h | 4 ++-- net/ipv4/inet_connection_sock.c | 18 ++++++++++++++---- net/ipv6/inet6_connection_sock.c | 2 +- 4 files changed, 18 insertions(+), 8 deletions(-) diff --git a/include/net/inet6_connection_sock.h b/include/net/inet6_connection_sock.h index 3207e58ee019..1866a676c810 100644 --- a/include/net/inet6_connection_sock.h +++ b/include/net/inet6_connection_sock.h @@ -23,7 +23,7 @@ struct sock; struct sockaddr; extern int inet6_csk_bind_conflict(const struct sock *sk, - const struct inet_bind_bucket *tb); + const struct inet_bind_bucket *tb, bool relax); extern struct dst_entry* inet6_csk_route_req(struct sock *sk, const struct request_sock *req); diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index dbf9aab34c82..46c9e2ccdf02 100644 --- a/include/net/inet_connection_sock.h +++ b/include/net/inet_connection_sock.h @@ -60,7 +60,7 @@ struct inet_connection_sock_af_ops { #endif void (*addr2sockaddr)(struct sock *sk, struct sockaddr *); int (*bind_conflict)(const struct sock *sk, - const struct inet_bind_bucket *tb); + const struct inet_bind_bucket *tb, bool relax); }; /** inet_connection_sock - INET connection oriented sock @@ -245,7 +245,7 @@ extern struct request_sock *inet_csk_search_req(const struct sock *sk, const __be32 raddr, const __be32 laddr); extern int inet_csk_bind_conflict(const struct sock *sk, - const struct inet_bind_bucket *tb); + const struct inet_bind_bucket *tb, bool relax); extern int inet_csk_get_port(struct sock *sk, unsigned short snum); extern struct dst_entry* inet_csk_route_req(struct sock *sk, diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index d19f32aca6ca..14409f111bc2 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -53,7 +53,7 @@ void inet_get_local_port_range(int *low, int *high) EXPORT_SYMBOL(inet_get_local_port_range); int inet_csk_bind_conflict(const struct sock *sk, - const struct inet_bind_bucket *tb) + const struct inet_bind_bucket *tb, bool relax) { struct sock *sk2; struct hlist_node *node; @@ -79,6 +79,14 @@ int inet_csk_bind_conflict(const struct sock *sk, sk2_rcv_saddr == sk_rcv_saddr(sk)) break; } + if (!relax && reuse && sk2->sk_reuse && + sk2->sk_state != TCP_LISTEN) { + const __be32 sk2_rcv_saddr = sk_rcv_saddr(sk2); + + if (!sk2_rcv_saddr || !sk_rcv_saddr(sk) || + sk2_rcv_saddr == sk_rcv_saddr(sk)) + break; + } } } return node != NULL; @@ -122,12 +130,13 @@ again: (tb->num_owners < smallest_size || smallest_size == -1)) { smallest_size = tb->num_owners; smallest_rover = rover; - if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) { + if (atomic_read(&hashinfo->bsockets) > (high - low) + 1 && + !inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { snum = smallest_rover; goto tb_found; } } - if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) { + if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, false)) { snum = rover; goto tb_found; } @@ -178,12 +187,13 @@ tb_found: goto success; } else { ret = 1; - if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) { + if (inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb, true)) { if (sk->sk_reuse && sk->sk_state != TCP_LISTEN && smallest_size != -1 && --attempts >= 0) { spin_unlock(&head->lock); goto again; } + goto fail_unlock; } } diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c index 02dd203d9eac..e6cee5292a0b 100644 --- a/net/ipv6/inet6_connection_sock.c +++ b/net/ipv6/inet6_connection_sock.c @@ -28,7 +28,7 @@ #include int inet6_csk_bind_conflict(const struct sock *sk, - const struct inet_bind_bucket *tb) + const struct inet_bind_bucket *tb, bool relax) { const struct sock *sk2; const struct hlist_node *node; -- 2.30.2