diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 7d519a46a844..88a34db265d8 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -910,22 +910,20 @@ pass: return 1; } -/* UDP encapsulation receive handler. See net/ipv4/udp.c. - * Return codes: - * 0 : success. - * <0: error - * >0: skb should be passed up to userspace as UDP. +/* UDP encapsulation receive and error receive handlers. + * See net/ipv4/udp.c for details. + * + * Note that these functions are called from inside an + * RCU-protected region, but without the socket being locked. + * + * Hence we use rcu_dereference_sk_user_data to access the + * tunnel data structure rather the usual l2tp_sk_to_tunnel + * accessor function. */ int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) { struct l2tp_tunnel *tunnel; - /* Note that this is called from the encap_rcv hook inside an - * RCU-protected region, but without the socket being locked. - * Hence we use rcu_dereference_sk_user_data to access the - * tunnel data structure rather the usual l2tp_sk_to_tunnel - * accessor function. - */ tunnel = rcu_dereference_sk_user_data(sk); if (!tunnel) goto pass_up; @@ -942,6 +940,29 @@ pass_up: } EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); +static void l2tp_udp_encap_err_recv(struct sock *sk, struct sk_buff *skb, int err, + __be16 port, u32 info, u8 *payload) +{ + struct l2tp_tunnel *tunnel; + + tunnel = rcu_dereference_sk_user_data(sk); + if (!tunnel || tunnel->fd < 0) + return; + + sk->sk_err = err; + sk_error_report(sk); + + if (ip_hdr(skb)->version == IPVERSION) { + if (inet_test_bit(RECVERR, sk)) + return ip_icmp_error(sk, skb, err, port, info, payload); +#if IS_ENABLED(CONFIG_IPV6) + } else { + if (inet6_test_bit(RECVERR6, sk)) + return ipv6_icmp_error(sk, skb, err, port, info, payload); +#endif + } +} + /************************************************************************ * Transmit handling ***********************************************************************/ @@ -1516,6 +1537,7 @@ int l2tp_tunnel_register(struct l2tp_tunnel *tunnel, struct net *net, .sk_user_data = tunnel, .encap_type = UDP_ENCAP_L2TPINUDP, .encap_rcv = l2tp_udp_encap_recv, + .encap_err_rcv = l2tp_udp_encap_err_recv, .encap_destroy = l2tp_udp_encap_destroy, };