ipv6: Disallow binding to v4-mapped address on v6-only socket.

A socket marked v6-only, can not receive or send traffic to v4-mapped
addresses.  Thus allowing binding to v4-mapped address on such a
socket makes no sense.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index fbf533cc9dce..7f092fa912bd 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -276,6 +276,13 @@ int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 
         /* Check if the address belongs to the host. */
         if (addr_type == IPV6_ADDR_MAPPED) {
+                /* Binding to v4-mapped address on a v6-only socket
+                 * makes no sense
+                 */
+                if (np->ipv6only) {
+                        err = -EINVAL;
+                        goto out;
+                }
                 v4addr = addr->sin6_addr.s6_addr32[3];
                 if (inet_addr_type(net, v4addr) != RTN_LOCAL) {
                         err = -EADDRNOTAVAIL;