[PATCH 3.18 17/31] ipv6: Consider sk_bound_dev_if when binding a socket to an address

From: Greg Kroah-Hartman
Date: Mon Feb 04 2019 - 05:38:22 EST

3.18-stable review patch. If anyone has any objections, please let me know.


From: David Ahern <dsahern@xxxxxxxxx>

[ 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@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
net/ipv6/af_inet6.c | 3 +++
1 file changed, 3 insertions(+)

--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -333,6 +333,9 @@ 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;