Re: How to find I/F to destination

[Patrick McHardy <kaber@trash.net>]

David Howells wrote:
> static void rxrpc_assess_MTU_size(struct rxrpc_peer *peer)
> {
> 	struct rtable *rt;
> 	struct flowi fl;
> 	int ret;
> 
> 	peer->if_mtu = 1500;
> 
> 	memset(&fl, 0, sizeof(fl));
> 
> 	switch (peer->srx.transport.family) {
> 	case AF_INET:
> 		fl.oif = 0;
> 		fl.proto = IPPROTO_UDP,
> 		fl.nl_u.ip4_u.saddr = 0;
> 		fl.nl_u.ip4_u.daddr = peer->srx.transport.sin.sin_addr.s_addr;
> 		fl.nl_u.ip4_u.tos = 0;
> 		/* assume AFS.CM talking to AFS.FS */
> 		fl.uli_u.ports.sport = htonl(7001);
> 		fl.uli_u.ports.dport = htonl(7000);

htons()

> 		break;
> 	default:
> 		BUG();
> 	}
> 
> 	ret = ip_route_output_key(&rt, &fl);
> 	if (ret < 0) {
> 		kleave(" [route err %d]", ret);
> 		return;
> 	}
> 
> 	peer->if_mtu = dst_mtu(&rt->u.dst);


You need dst_release(&rt->u.dst) here.