Before I can enable rtnetlink to work in all network namespaces
I need to be certain that something won't break.  So this
patch deliberately disables all of the rtnletlink methods in everything
except the initial network namespace.  After the methods have been
audited this extra check can be disabled.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 net/bridge/br_netlink.c |    9 +++++++++
 net/core/fib_rules.c    |   11 +++++++++++
 net/core/neighbour.c    |   18 ++++++++++++++++++
 net/core/rtnetlink.c    |   19 +++++++++++++++++++
 net/decnet/dn_dev.c     |   12 ++++++++++++
 net/decnet/dn_fib.c     |    8 ++++++++
 net/decnet/dn_route.c   |    8 ++++++++
 net/decnet/dn_table.c   |    4 ++++
 net/ipv4/devinet.c      |   12 ++++++++++++
 net/ipv4/fib_frontend.c |   12 ++++++++++++
 net/ipv4/route.c        |    4 ++++
 net/ipv6/addrconf.c     |   31 +++++++++++++++++++++++++++++++
 net/ipv6/ip6_fib.c      |    4 ++++
 net/ipv6/route.c        |   12 ++++++++++++
 net/sched/act_api.c     |   10 ++++++++++
 net/sched/cls_api.c     |   10 ++++++++++
 net/sched/sch_api.c     |   21 +++++++++++++++++++++
 17 files changed, 205 insertions(+), 0 deletions(-)

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 53ab8e0..a4ffa2b 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -13,6 +13,7 @@
 #include <linux/kernel.h>
 #include <net/rtnetlink.h>
 #include <net/net_namespace.h>
+#include <net/sock.h>
 #include "br_private.h"
 
 static inline size_t br_nlmsg_size(void)
@@ -107,9 +108,13 @@ errout:
  */
 static int br_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	struct net_device *dev;
 	int idx;
 
+	if (net != &init_net)
+		return 0;
+
 	idx = 0;
 	for_each_netdev(&init_net, dev) {
 		/* not a bridge port */
@@ -135,12 +140,16 @@ skip:
  */
 static int br_rtm_setlink(struct sk_buff *skb,  struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct ifinfomsg *ifm;
 	struct nlattr *protinfo;
 	struct net_device *dev;
 	struct net_bridge_port *p;
 	u8 new_state;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (nlmsg_len(nlh) < sizeof(*ifm))
 		return -EINVAL;
 
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 13de6f5..357bfa0 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -206,6 +206,9 @@ static int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 	struct nlattr *tb[FRA_MAX+1];
 	int err = -EINVAL, unresolved = 0;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 		goto errout;
 
@@ -336,12 +339,16 @@ errout:
 
 static int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct fib_rule_hdr *frh = nlmsg_data(nlh);
 	struct fib_rules_ops *ops = NULL;
 	struct fib_rule *rule, *tmp;
 	struct nlattr *tb[FRA_MAX+1];
 	int err = -EINVAL;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh)))
 		goto errout;
 
@@ -517,9 +524,13 @@ skip:
 
 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	struct fib_rules_ops *ops;
 	int idx = 0, family;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	family = rtnl_msg_family(cb->nlh);
 	if (family != AF_UNSPEC) {
 		/* Protocol specific dump request */
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index c52df85..27001db 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1448,6 +1448,9 @@ static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct net_device *dev = NULL;
 	int err = -EINVAL;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (nlmsg_len(nlh) < sizeof(*ndm))
 		goto out;
 
@@ -1514,6 +1517,9 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct net_device *dev = NULL;
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
 	if (err < 0)
 		goto out;
@@ -1788,11 +1794,15 @@ static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = {
 
 static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct neigh_table *tbl;
 	struct ndtmsg *ndtmsg;
 	struct nlattr *tb[NDTA_MAX+1];
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ndtmsg), tb, NDTA_MAX,
 			  nl_neightbl_policy);
 	if (err < 0)
@@ -1912,11 +1922,15 @@ errout:
 
 static int neightbl_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	int family, tidx, nidx = 0;
 	int tbl_skip = cb->args[0];
 	int neigh_skip = cb->args[1];
 	struct neigh_table *tbl;
 
+	if (net != &init_net)
+		return 0;
+
 	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
 
 	read_lock(&neigh_tbl_lock);
@@ -2041,9 +2055,13 @@ out:
 
 static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	struct neigh_table *tbl;
 	int t, family, s_t;
 
+	if (net != &init_net)
+		return 0;
+
 	read_lock(&neigh_tbl_lock);
 	family = ((struct rtgenmsg *) nlmsg_data(cb->nlh))->rtgen_family;
 	s_t = cb->args[0];
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 8bc68e6..56fc4f9 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -707,6 +707,9 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 	int s_idx = cb->args[0];
 	struct net_device *dev;
 
+	if (net != &init_net)
+		return 0;
+
 	idx = 0;
 	for_each_netdev(net, dev) {
 		if (idx < s_idx)
@@ -909,6 +912,9 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct nlattr *tb[IFLA_MAX+1];
 	char ifname[IFNAMSIZ];
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 	if (err < 0)
 		goto errout;
@@ -957,6 +963,9 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct nlattr *tb[IFLA_MAX+1];
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 	if (err < 0)
 		return err;
@@ -1038,6 +1047,9 @@ static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct nlattr *linkinfo[IFLA_INFO_MAX+1];
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 #ifdef CONFIG_KMOD
 replay:
 #endif
@@ -1164,6 +1176,9 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 	struct sk_buff *nskb;
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
 	if (err < 0)
 		return err;
@@ -1199,9 +1214,13 @@ errout:
 
 static int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	int idx;
 	int s_idx = cb->family;
 
+	if (net != &init_net)
+		return 0;
+
 	if (s_idx == 0)
 		s_idx = 1;
 	for (idx=1; idx<NPROTO; idx++) {
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index 26130af..6e82f7a 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -647,12 +647,16 @@ static const struct nla_policy dn_ifa_policy[IFA_MAX+1] = {
 
 static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct nlattr *tb[IFA_MAX+1];
 	struct dn_dev *dn_db;
 	struct ifaddrmsg *ifm;
 	struct dn_ifaddr *ifa, **ifap;
 	int err = -EADDRNOTAVAIL;
 
+	if (net != &init_net)
+		goto errout;
+
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
 	if (err < 0)
 		goto errout;
@@ -679,6 +683,7 @@ errout:
 
 static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct nlattr *tb[IFA_MAX+1];
 	struct net_device *dev;
 	struct dn_dev *dn_db;
@@ -686,6 +691,9 @@ static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	struct dn_ifaddr *ifa;
 	int err;
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
 	if (err < 0)
 		return err;
@@ -791,11 +799,15 @@ errout:
 
 static int dn_nl_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
 {
+	struct net *net = skb->sk->sk_net;
 	int idx, dn_idx = 0, skip_ndevs, skip_naddr;
 	struct net_device *dev;
 	struct dn_dev *dn_db;
 	struct dn_ifaddr *ifa;
 
+	if (net != &init_net)
+		return 0;
+
 	skip_ndevs = cb->args[0];
 	skip_naddr = cb->args[1];
 
diff --git a/net/decnet/dn_fib.c b/net/decnet/dn_fib.c
index 3760a20..5413e1b 100644
--- a/net/decnet/dn_fib.c
+++ b/net/decnet/dn_fib.c
@@ -506,10 +506,14 @@ static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
 
 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct dn_fib_table *tb;
 	struct rtattr **rta = arg;
 	struct rtmsg *r = NLMSG_DATA(nlh);
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (dn_fib_check_attr(r, rta))
 		return -EINVAL;
 
@@ -522,10 +526,14 @@ static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *
 
 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
+	struct net *net = skb->sk->sk_net;
 	struct dn_fib_table *tb;
 	struct rtattr **rta = arg;
 	struct rtmsg *r = NLMSG_DATA(nlh);
 
+	if (net != &init_net)
+		return -EINVAL;
+
 	if (dn_fib_check_attr(r, rta))
 		return -EINVAL;
 
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index b7ebf99..a16374b 100644
--- a/