From 8141ed9fcedb278f4a3a78680591bef1e55f75fb Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Mon, 21 Jan 2013 02:00:03 +0000 Subject: ipv4: Add a socket release callback for datagram sockets This implements a socket release callback function to check if the socket cached route got invalid during the time we owned the socket. The function is used from udp, raw and ping sockets. Signed-off-by: Steffen Klassert Signed-off-by: David S. Miller --- net/ipv4/datagram.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'net/ipv4/datagram.c') diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c index 424fafbc8cb0..b28e863fe0a7 100644 --- a/net/ipv4/datagram.c +++ b/net/ipv4/datagram.c @@ -85,3 +85,28 @@ out: return err; } EXPORT_SYMBOL(ip4_datagram_connect); + +void ip4_datagram_release_cb(struct sock *sk) +{ + const struct inet_sock *inet = inet_sk(sk); + const struct ip_options_rcu *inet_opt; + __be32 daddr = inet->inet_daddr; + struct flowi4 fl4; + struct rtable *rt; + + if (! __sk_dst_get(sk) || __sk_dst_check(sk, 0)) + return; + + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + if (inet_opt && inet_opt->opt.srr) + daddr = inet_opt->opt.faddr; + rt = ip_route_output_ports(sock_net(sk), &fl4, sk, daddr, + inet->inet_saddr, inet->inet_dport, + inet->inet_sport, sk->sk_protocol, + RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); + if (!IS_ERR(rt)) + __sk_dst_set(sk, &rt->dst); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(ip4_datagram_release_cb); -- cgit v1.2.3