ipv6: protect protocols not handling ipv4 from v4 connection/bind attempts
Some ipv6 protocols cannot handle ipv4 addresses, so we must not allow
connecting and binding to them. sendmsg logic does already check msg->name
for this but must trust already connected sockets which could be set up
for connection to ipv4 address family.
Per-socket flag ipv6only is of no use here, as it is under users control
by setsockopt.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index aab5f74..7704ea9 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -371,6 +371,9 @@
if (addr_len < sizeof(*lsa))
return -EINVAL;
+ if (usin->sin6_family != AF_INET6)
+ return -EINVAL;
+
addr_type = ipv6_addr_type(&usin->sin6_addr);
if (addr_type & IPV6_ADDR_MULTICAST)
return -EINVAL;