tcp: must block bh in __inet_twsk_hashdance()

__inet_twsk_hashdance() might be called from process context,
better block BH before acquiring bind hash and established locks

Fixes: c10d9310ed ("tcp: do not assume TCP code is non preemptible")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2016-05-03 17:10:50 -07:00 committed by David S. Miller
parent 46cc6e4976
commit 614bdd4d6e

View File

@ -94,7 +94,7 @@ static void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
}
/*
* Enter the time wait state. This is called with locally disabled BH.
* Enter the time wait state.
* Essentially we whip up a timewait bucket, copy the relevant info into it
* from the SK, and mess with hash chains and list linkage.
*/
@ -112,7 +112,7 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
*/
bhead = &hashinfo->bhash[inet_bhashfn(twsk_net(tw), inet->inet_num,
hashinfo->bhash_size)];
spin_lock(&bhead->lock);
spin_lock_bh(&bhead->lock);
tw->tw_tb = icsk->icsk_bind_hash;
WARN_ON(!icsk->icsk_bind_hash);
inet_twsk_add_bind_node(tw, &tw->tw_tb->owners);
@ -138,7 +138,7 @@ void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
if (__sk_nulls_del_node_init_rcu(sk))
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
spin_unlock(lock);
spin_unlock_bh(lock);
}
EXPORT_SYMBOL_GPL(__inet_twsk_hashdance);