[PATCH net-next RFC v1 11/27] afnetns: validate afnetns in inet_allow_bind

[Hannes Frederic Sowa]

Signed-off-by: Hannes Frederic Sowa <han...@stressinduktion.org>
---
 net/ipv4/af_inet.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index aee599e23137e7..5f11399bafd16f 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -453,6 +453,17 @@ int inet_allow_bind(struct sock *sk, __be32 addr)
            chk_addr_ret != RTN_BROADCAST)
                return -EADDRNOTAVAIL;
 
+       if (chk_addr_ret == RTN_LOCAL &&
+           net_afnetns(net) != sock_afnetns(sk)) {
+               struct afnetns *afnetns;
+
+               rcu_read_lock();
+               afnetns = ifa_find_afnetns_rcu(net, addr);
+               if (afnetns != sock_afnetns(sk))
+                       chk_addr_ret = -EADDRNOTAVAIL;
+               rcu_read_unlock();
+       }
+
        return chk_addr_ret;
 }
 EXPORT_SYMBOL(inet_allow_bind);
-- 
2.9.3