diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index a21d02ac715e..68021c0c1783 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -297,40 +297,46 @@ void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb) /* rehashing is required only in MP mode as P2P has one peer * only and thus there is no hashtable */ - if (peer->ovpn->mode == OVPN_MODE_MP) { - spin_lock_bh(&peer->ovpn->lock); - spin_lock_bh(&peer->lock); - bind = rcu_dereference_protected(peer->bind, - lockdep_is_held(&peer->lock)); - if (unlikely(!bind)) { - spin_unlock_bh(&peer->lock); - spin_unlock_bh(&peer->ovpn->lock); - return; - } + if (peer->ovpn->mode != OVPN_MODE_MP) + return; - /* This function may be invoked concurrently, therefore another - * float may have happened in parallel: perform rehashing - * using the peer->bind->remote directly as key - */ + spin_lock_bh(&peer->ovpn->lock); + spin_lock_bh(&peer->lock); + bind = rcu_dereference_protected(peer->bind, + lockdep_is_held(&peer->lock)); + if (unlikely(!bind)) + goto unlock2; - switch (bind->remote.in4.sin_family) { - case AF_INET: - salen = sizeof(*sa); - break; - case AF_INET6: - salen = sizeof(*sa6); - break; - } + /* peer may have been concurrently removed between the caller's + * initial lookup and our acquisition of ovpn->lock; skip the + * rehash so we don't re-insert a removed peer + */ + if (unlikely(hlist_unhashed(&peer->hash_entry_id))) + goto unlock2; - /* remove old hashing */ - hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr); - /* re-add with new transport address */ - nhead = ovpn_get_hash_head(peer->ovpn->peers->by_transp_addr, - &bind->remote, salen); - hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); - spin_unlock_bh(&peer->lock); - spin_unlock_bh(&peer->ovpn->lock); + /* This function may be invoked concurrently, therefore another + * float may have happened in parallel: perform rehashing + * using the peer->bind->remote directly as key + */ + + switch (bind->remote.in4.sin_family) { + case AF_INET: + salen = sizeof(*sa); + break; + case AF_INET6: + salen = sizeof(*sa6); + break; } + + /* remove old hashing */ + hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr); + /* re-add with new transport address */ + nhead = ovpn_get_hash_head(peer->ovpn->peers->by_transp_addr, + &bind->remote, salen); + hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); +unlock2: + spin_unlock_bh(&peer->lock); + spin_unlock_bh(&peer->ovpn->lock); return; unlock: spin_unlock_bh(&peer->lock); @@ -906,6 +912,13 @@ void ovpn_peer_hash_vpn_ip(struct ovpn_peer *peer) if (peer->ovpn->mode != OVPN_MODE_MP) return; + /* peer may have been concurrently removed between the caller's + * initial lookup and our acquisition of ovpn->lock; skip the + * rehash so we don't re-insert a removed peer + */ + if (hlist_unhashed(&peer->hash_entry_id)) + return; + if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) { /* remove potential old hashing */ hlist_nulls_del_init_rcu(&peer->hash_entry_addr4);