releases/4.4.172/ipv6-consider-sk_bound_dev_if-when-binding-a-socket-to-a-v4-mapped-address.patch

   1 From foo@baz Wed Jan 23 08:29:58 CET 2019
   2 From: David Ahern <dsahern@gmail.com>
   3 Date: Fri, 4 Jan 2019 16:58:15 -0800
   4 Subject: ipv6: Consider sk_bound_dev_if when binding a socket to a v4 mapped address
   5
   6 From: David Ahern <dsahern@gmail.com>
   7
   8 [ Upstream commit ec90ad334986fa5856d11dd272f7f22fa86c55c4 ]
   9
  10 Similar to c5ee066333eb ("ipv6: Consider sk_bound_dev_if when binding a
  11 socket to an address"), binding a socket to v4 mapped addresses needs to
  12 consider if the socket is bound to a device.
  13
  14 This problem also exists from the beginning of git history.
  15
  16 Signed-off-by: David Ahern <dsahern@gmail.com>
  17 Signed-off-by: David S. Miller <davem@davemloft.net>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19 ---
  20  net/ipv6/af_inet6.c |   11 ++++++++++-
  21  1 file changed, 10 insertions(+), 1 deletion(-)
  22
  23 --- a/net/ipv6/af_inet6.c
  24 +++ b/net/ipv6/af_inet6.c
  25 @@ -292,6 +292,7 @@ int inet6_bind(struct socket *sock, stru
  26
  27         /* Check if the address belongs to the host. */
  28         if (addr_type == IPV6_ADDR_MAPPED) {
  29 +               struct net_device *dev = NULL;
  30                 int chk_addr_ret;
  31
  32                 /* Binding to v4-mapped address on a v6-only socket
  33 @@ -302,9 +303,17 @@ int inet6_bind(struct socket *sock, stru
  34                         goto out;
  35                 }
  36
  37 +               if (sk->sk_bound_dev_if) {
  38 +                       dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
  39 +                       if (!dev) {
  40 +                               err = -ENODEV;
  41 +                               goto out;
  42 +                       }
  43 +               }
  44 +
  45                 /* Reproduce AF_INET checks to make the bindings consistent */
  46                 v4addr = addr->sin6_addr.s6_addr32[3];
  47 -               chk_addr_ret = inet_addr_type(net, v4addr);
  48 +               chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr);
  49                 if (!net->ipv4.sysctl_ip_nonlocal_bind &&
  50                     !(inet->freebind || inet->transparent) &&
  51                     v4addr != htonl(INADDR_ANY) &&