releases/4.4.173/ipv6-consider-sk_bound_dev_if-when-binding-a-socket-to-an-address.patch

From foo@baz Sat Feb  2 11:39:00 CET 2019
From: David Ahern <dsahern@gmail.com>
Date: Wed, 2 Jan 2019 18:57:09 -0800
Subject: ipv6: Consider sk_bound_dev_if when binding a socket to an address

From: David Ahern <dsahern@gmail.com>

[ Upstream commit c5ee066333ebc322a24a00a743ed941a0c68617e ]

IPv6 does not consider if the socket is bound to a device when binding
to an address. The result is that a socket can be bound to eth0 and then
bound to the address of eth1. If the device is a VRF, the result is that
a socket can only be bound to an address in the default VRF.

Resolve by considering the device if sk_bound_dev_if is set.

This problem exists from the beginning of git history.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv6/af_inet6.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -345,6 +345,9 @@ int inet6_bind(struct socket *sock, stru
 					err = -EINVAL;
 					goto out_unlock;
 				}
+			}
+
+			if (sk->sk_bound_dev_if) {
 				dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 				if (!dev) {
 					err = -ENODEV;