inet: Pass inetpeer root into inet_getpeer*() interfaces.

Otherwise we reference potentially non-existing members when
ipv6 is disabled.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/inetpeer.h

@@ -83,11 +83,11 @@ static inline bool inet_metrics_new(const struct inet_peer *p)
 }
 
 /* can be called with or without local BH being disabled */
-struct inet_peer *inet_getpeer(struct net *net,
+struct inet_peer *inet_getpeer(struct inet_peer_base *base,
 			       const struct inetpeer_addr *daddr,
 			       int create);
 
-static inline struct inet_peer *inet_getpeer_v4(struct net *net,
+static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
 						__be32 v4daddr,
 						int create)
 {
@@ -95,10 +95,10 @@ static inline struct inet_peer *inet_getpeer_v4(struct net *net,
 
 	daddr.addr.a4 = v4daddr;
 	daddr.family = AF_INET;
-	return inet_getpeer(net, &daddr, create);
+	return inet_getpeer(base, &daddr, create);
 }
 
-static inline struct inet_peer *inet_getpeer_v6(struct net *net,
+static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
 						const struct in6_addr *v6daddr,
 						int create)
 {
@@ -106,7 +106,7 @@ static inline struct inet_peer *inet_getpeer_v6(struct net *net,
 
 	*(struct in6_addr *)daddr.addr.a6 = *v6daddr;
 	daddr.family = AF_INET6;
-	return inet_getpeer(net, &daddr, create);
+	return inet_getpeer(base, &daddr, create);
 }
 
 /* can be called from BH context or outside */

net/ipv4/inetpeer.c

@@ -391,12 +391,6 @@ static void unlink_from_pool(struct inet_peer *p, struct inet_peer_base *base,
 	call_rcu(&p->rcu, inetpeer_free_rcu);
 }
 
-static struct inet_peer_base *family_to_base(struct net *net,
-					     int family)
-{
-	return family == AF_INET ? net->ipv4.peers : net->ipv6.peers;
-}
-
 /* perform garbage collect on all items stacked during a lookup */
 static int inet_peer_gc(struct inet_peer_base *base,
 			struct inet_peer __rcu **stack[PEER_MAXDEPTH],
@@ -434,12 +428,11 @@ static int inet_peer_gc(struct inet_peer_base *base,
 	return cnt;
 }
 
-struct inet_peer *inet_getpeer(struct net *net,
+struct inet_peer *inet_getpeer(struct inet_peer_base *base,
 			       const struct inetpeer_addr *daddr,
 			       int create)
 {
 	struct inet_peer __rcu **stack[PEER_MAXDEPTH], ***stackptr;
-	struct inet_peer_base *base = family_to_base(net, daddr->family);
 	struct inet_peer *p;
 	unsigned int sequence;
 	int invalidated, gccnt = 0;

net/ipv4/ip_fragment.c

@@ -184,7 +184,7 @@ static void ip4_frag_init(struct inet_frag_queue *q, void *a)
 	qp->daddr = arg->iph->daddr;
 	qp->user = arg->user;
 	qp->peer = sysctl_ipfrag_max_dist ?
-		inet_getpeer_v4(net, arg->iph->saddr, 1) : NULL;
+		inet_getpeer_v4(net->ipv4.peers, arg->iph->saddr, 1) : NULL;
 }
 
 static __inline__ void ip4_frag_free(struct inet_frag_queue *q)

net/ipv4/route.c

@@ -1328,7 +1328,7 @@ void rt_bind_peer(struct rtable *rt, __be32 daddr, int create)
 	struct net *net = dev_net(rt->dst.dev);
 	struct inet_peer *peer;
 
-	peer = inet_getpeer_v4(net, daddr, create);
+	peer = inet_getpeer_v4(net->ipv4.peers, daddr, create);
 
 	if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL)
 		inet_putpeer(peer);
@@ -1684,7 +1684,7 @@ unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph,
 	unsigned short est_mtu = 0;
 	struct inet_peer *peer;
 
-	peer = inet_getpeer_v4(net, iph->daddr, 1);
+	peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
 	if (peer) {
 		unsigned short mtu = new_mtu;
 
@@ -1929,7 +1929,7 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4,
 	if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
 		create = 1;
 
-	rt->peer = peer = inet_getpeer_v4(net, rt->rt_dst, create);
+	rt->peer = peer = inet_getpeer_v4(net->ipv4.peers, rt->rt_dst, create);
 	if (peer) {
 		rt->rt_peer_genid = rt_peer_genid();
 		if (inet_metrics_new(peer))

net/ipv6/route.c

@@ -306,7 +306,7 @@ void rt6_bind_peer(struct rt6_info *rt, int create)
 	struct net *net = dev_net(rt->dst.dev);
 	struct inet_peer *peer;
 
-	peer = inet_getpeer_v6(net, &rt->rt6i_dst.addr, create);
+	peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, create);
 	if (peer && cmpxchg(&rt->rt6i_peer, NULL, peer) != NULL)
 		inet_putpeer(peer);
 	else