net/ipv4: bind ip_nonlocal_bind to current netns

net.ipv4.ip_nonlocal_bind sysctl was global to all network
namespaces. This patch allows to set a different value for each
network namespace.

Signed-off-by: Vincent Bernat <vincent@bernat.im>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index d156b3c..b537bd9 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -418,10 +418,6 @@
 }
 EXPORT_SYMBOL(inet_release);
 
-/* It is off by default, see below. */
-int sysctl_ip_nonlocal_bind __read_mostly;
-EXPORT_SYMBOL(sysctl_ip_nonlocal_bind);
-
 int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 {
 	struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
@@ -461,7 +457,7 @@
 	 *  is temporarily down)
 	 */
 	err = -EADDRNOTAVAIL;
-	if (!sysctl_ip_nonlocal_bind &&
+	if (!net->ipv4.sysctl_ip_nonlocal_bind &&
 	    !(inet->freebind || inet->transparent) &&
 	    addr->sin_addr.s_addr != htonl(INADDR_ANY) &&
 	    chk_addr_ret != RTN_LOCAL &&