netns: Add network namespace argument to rt6_fill_node() and ipv6_dev_get_saddr()

ipv6_dev_get_saddr() blindly de-references dst_dev to get the network
namespace, but some callers might pass NULL.  Change callers to pass a
namespace pointer instead.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index a7842c5..e2d3b758 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1106,13 +1106,12 @@
 	return ret;
 }
 
-int ipv6_dev_get_saddr(struct net_device *dst_dev,
+int ipv6_dev_get_saddr(struct net *net, struct net_device *dst_dev,
 		       const struct in6_addr *daddr, unsigned int prefs,
 		       struct in6_addr *saddr)
 {
 	struct ipv6_saddr_score scores[2],
 				*score = &scores[0], *hiscore = &scores[1];
-	struct net *net = dev_net(dst_dev);
 	struct ipv6_saddr_dst dst;
 	struct net_device *dev;
 	int dst_type;
diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 8d05527..f5de3f9 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -93,7 +93,8 @@
 			if (flags & RT6_LOOKUP_F_SRCPREF_COA)
 				srcprefs |= IPV6_PREFER_SRC_COA;
 
-			if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
+			if (ipv6_dev_get_saddr(net,
+					       ip6_dst_idev(&rt->u.dst)->dev,
 					       &flp->fl6_dst, srcprefs,
 					       &saddr))
 				goto again;
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 52dddc2..29c7c99 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -378,6 +378,7 @@
 
 	arg.skb = skb;
 	arg.cb = cb;
+	arg.net = net;
 	w->args = &arg;
 
 	for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index a4402de..0e844c2 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -934,7 +934,7 @@
 		goto out_err_release;
 
 	if (ipv6_addr_any(&fl->fl6_src)) {
-		err = ipv6_dev_get_saddr(ip6_dst_idev(*dst)->dev,
+		err = ipv6_dev_get_saddr(net, ip6_dst_idev(*dst)->dev,
 					 &fl->fl6_dst,
 					 sk ? inet6_sk(sk)->srcprefs : 0,
 					 &fl->fl6_src);
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index beb48e3..f1c62ba 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -549,7 +549,7 @@
 			override = 0;
 		in6_ifa_put(ifp);
 	} else {
-		if (ipv6_dev_get_saddr(dev, daddr,
+		if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
 				       inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
 				       &tmpaddr))
 			return;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 41b165f..9af6115 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2106,7 +2106,8 @@
 	       + nla_total_size(sizeof(struct rta_cacheinfo));
 }
 
-static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
+static int rt6_fill_node(struct net *net,
+			 struct sk_buff *skb, struct rt6_info *rt,
 			 struct in6_addr *dst, struct in6_addr *src,
 			 int iif, int type, u32 pid, u32 seq,
 			 int prefix, int nowait, unsigned int flags)
@@ -2189,7 +2190,7 @@
 	} else if (dst) {
 		struct inet6_dev *idev = ip6_dst_idev(&rt->u.dst);
 		struct in6_addr saddr_buf;
-		if (ipv6_dev_get_saddr(idev ? idev->dev : NULL,
+		if (ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
 				       dst, 0, &saddr_buf) == 0)
 			NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
 	}
@@ -2234,7 +2235,8 @@
 	} else
 		prefix = 0;
 
-	return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
+	return rt6_fill_node(arg->net,
+		     arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
 		     NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
 		     prefix, 0, NLM_F_MULTI);
 }
@@ -2300,7 +2302,7 @@
 	rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl);
 	skb->dst = &rt->u.dst;
 
-	err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
+	err = rt6_fill_node(net, skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
 			    RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
 			    nlh->nlmsg_seq, 0, 0, 0);
 	if (err < 0) {
@@ -2327,7 +2329,7 @@
 	if (skb == NULL)
 		goto errout;
 
-	err = rt6_fill_node(skb, rt, NULL, NULL, 0,
+	err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
 				event, info->pid, seq, 0, 0, 0);
 	if (err < 0) {
 		/* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 8f1e054..08e4cbb 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -52,12 +52,14 @@
 static int xfrm6_get_saddr(xfrm_address_t *saddr, xfrm_address_t *daddr)
 {
 	struct dst_entry *dst;
+	struct net_device *dev;
 
 	dst = xfrm6_dst_lookup(0, NULL, daddr);
 	if (IS_ERR(dst))
 		return -EHOSTUNREACH;
 
-	ipv6_dev_get_saddr(ip6_dst_idev(dst)->dev,
+	dev = ip6_dst_idev(dst)->dev;
+	ipv6_dev_get_saddr(dev_net(dev), dev,
 			   (struct in6_addr *)&daddr->a6, 0,
 			   (struct in6_addr *)&saddr->a6);
 	dst_release(dst);