diff options
| -rw-r--r-- | net/ipv4/inet_timewait_sock.c | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c index 1f5d508bb18b..d38ca7c77b93 100644 --- a/net/ipv4/inet_timewait_sock.c +++ b/net/ipv4/inet_timewait_sock.c @@ -427,31 +427,40 @@ void inet_twsk_purge(struct net *net, struct inet_hashinfo *hashinfo, struct inet_timewait_sock *tw; struct sock *sk; struct hlist_nulls_node *node; - int h; + unsigned int slot; - local_bh_disable(); - for (h = 0; h <= hashinfo->ehash_mask; h++) { - struct inet_ehash_bucket *head = - inet_ehash_bucket(hashinfo, h); - spinlock_t *lock = inet_ehash_lockp(hashinfo, h); + for (slot = 0; slot <= hashinfo->ehash_mask; slot++) { + struct inet_ehash_bucket *head = &hashinfo->ehash[slot]; +restart_rcu: + rcu_read_lock(); restart: - spin_lock(lock); - sk_nulls_for_each(sk, node, &head->twchain) { - + sk_nulls_for_each_rcu(sk, node, &head->twchain) { tw = inet_twsk(sk); if (!net_eq(twsk_net(tw), net) || tw->tw_family != family) continue; - atomic_inc(&tw->tw_refcnt); - spin_unlock(lock); + if (unlikely(!atomic_inc_not_zero(&tw->tw_refcnt))) + continue; + + if (unlikely(!net_eq(twsk_net(tw), net) || + tw->tw_family != family)) { + inet_twsk_put(tw); + goto restart; + } + + rcu_read_unlock(); inet_twsk_deschedule(tw, twdr); inet_twsk_put(tw); - - goto restart; + goto restart_rcu; } - spin_unlock(lock); + /* If the nulls value we got at the end of this lookup is + * not the expected one, we must restart lookup. + * We probably met an item that was moved to another chain. + */ + if (get_nulls_value(node) != slot) + goto restart; + rcu_read_unlock(); } - local_bh_enable(); } EXPORT_SYMBOL_GPL(inet_twsk_purge); |