tcp: bind() fix when many ports are bound

Port autoselection done by kernel only works when number of bound
sockets is under a threshold (typically 30000).

When this threshold is over, we must check if there is a conflict before
exiting first loop in inet_csk_get_port()

Change inet_csk_bind_conflict() to forbid two reuse-enabled sockets to
bind on same (address,port) tuple (with a non ANY address)

Same change for inet6_csk_bind_conflict()

Reported-by: Gaspar Chilingarov <gasparch@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2010-04-21 09:26:15 +00:00 committed by David S. Miller
parent 24acc68956
commit fda48a0d7a
2 changed files with 21 additions and 10 deletions

View File

@ -70,13 +70,17 @@ int inet_csk_bind_conflict(const struct sock *sk,
(!sk->sk_bound_dev_if ||
!sk2->sk_bound_dev_if ||
sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
if (!reuse || !sk2->sk_reuse ||
sk2->sk_state == TCP_LISTEN) {
const __be32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
if (!sk2_rcv_saddr || !sk_rcv_saddr ||
sk2_rcv_saddr == sk_rcv_saddr)
break;
}
} else if (reuse && sk2->sk_reuse &&
sk2_rcv_saddr &&
sk2_rcv_saddr == sk_rcv_saddr)
break;
}
}
return node != NULL;
@ -120,9 +124,11 @@ again:
smallest_size = tb->num_owners;
smallest_rover = rover;
if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {
spin_unlock(&head->lock);
snum = smallest_rover;
goto have_snum;
if (!inet_csk(sk)->icsk_af_ops->bind_conflict(sk, tb)) {
spin_unlock(&head->lock);
snum = smallest_rover;
goto have_snum;
}
}
}
goto next;

View File

@ -42,11 +42,16 @@ int inet6_csk_bind_conflict(const struct sock *sk,
if (sk != sk2 &&
(!sk->sk_bound_dev_if ||
!sk2->sk_bound_dev_if ||
sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
(!sk->sk_reuse || !sk2->sk_reuse ||
sk2->sk_state == TCP_LISTEN) &&
ipv6_rcv_saddr_equal(sk, sk2))
break;
sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
if ((!sk->sk_reuse || !sk2->sk_reuse ||
sk2->sk_state == TCP_LISTEN) &&
ipv6_rcv_saddr_equal(sk, sk2))
break;
else if (sk->sk_reuse && sk2->sk_reuse &&
!ipv6_addr_any(inet6_rcv_saddr(sk2)) &&
ipv6_rcv_saddr_equal(sk, sk2))
break;
}
}
return node != NULL;