tcp: Get rid of inetpeer special cases.

The get_peer method TCP uses is full of special cases that make no
sense accommodating, and it also gets in the way of doing more
reasonable things here.

First of all, if the socket doesn't have a usable cached route, there
is no sense in trying to optimize timewait recycling.

Likewise for the case where we have IP options, such as SRR enabled,
that make the IP header destination address (and thus the destination
address of the route key) differ from that of the connection's
destination address.

Just return a NULL peer in these cases, and thus we're also able to
get rid of the clumsy inetpeer release logic.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 13 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 218433c..b5ecf37 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1732,23 +1732,18 @@ do_time_wait:
 	goto discard_it;
 }
 
-static struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
+static struct inet_peer *tcp_v6_get_peer(struct sock *sk)
 {
 	struct rt6_info *rt = (struct rt6_info *) __sk_dst_get(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
-	struct net *net = sock_net(sk);
-	struct inet_peer *peer;
-
-	if (!rt ||
-	    !ipv6_addr_equal(&np->daddr, &rt->rt6i_dst.addr)) {
-		peer = inet_getpeer_v6(net, &np->daddr, 1);
-		*release_it = true;
-	} else {
-		peer = rt6_get_peer_create(rt);
-		*release_it = false;
-	}
 
-	return peer;
+	/* If we don't have a valid cached route, or we're doing IP
+	 * options which make the IPv6 header destination address
+	 * different from our peer's, do not bother with this.
+	 */
+	if (!rt || !ipv6_addr_equal(&np->daddr, &rt->rt6i_dst.addr))
+		return NULL;
+	return rt6_get_peer_create(rt);
 }
 
 static void *tcp_v6_tw_get_peer(struct sock *sk)