[PATCH 4.14 01/63] ipv6: Consider sk_bound_dev_if when binding a socket to a v4 mapped address

From: Greg Kroah-Hartman
Date: Thu Jan 24 2019 - 15:05:49 EST


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

------------------

From: David Ahern <dsahern@xxxxxxxxx>

[ Upstream commit ec90ad334986fa5856d11dd272f7f22fa86c55c4 ]

Similar to c5ee066333eb ("ipv6: Consider sk_bound_dev_if when binding a
socket to an address"), binding a socket to v4 mapped addresses needs to
consider if the socket is bound to a device.

This problem also 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 | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -317,6 +317,7 @@ int inet6_bind(struct socket *sock, stru

/* Check if the address belongs to the host. */
if (addr_type == IPV6_ADDR_MAPPED) {
+ struct net_device *dev = NULL;
int chk_addr_ret;

/* Binding to v4-mapped address on a v6-only socket
@@ -327,9 +328,17 @@ int inet6_bind(struct socket *sock, stru
goto out;
}

+ if (sk->sk_bound_dev_if) {
+ dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
+ if (!dev) {
+ err = -ENODEV;
+ goto out;
+ }
+ }
+
/* Reproduce AF_INET checks to make the bindings consistent */
v4addr = addr->sin6_addr.s6_addr32[3];
- chk_addr_ret = inet_addr_type(net, v4addr);
+ chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr);
if (!net->ipv4.sysctl_ip_nonlocal_bind &&
!(inet->freebind || inet->transparent) &&
v4addr != htonl(INADDR_ANY) &&