net: Make CAP_NET_BIND_SERVICE per user namespace

Allow privileged users in any user namespace to bind to
privileged sockets in network namespaces they control.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 4f5f22061e1c..24b384b7903e 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -474,6 +474,7 @@ int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
         struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
         struct sock *sk = sock->sk;
         struct inet_sock *inet = inet_sk(sk);
+        struct net *net = sock_net(sk);
         unsigned short snum;
         int chk_addr_ret;
         int err;
@@ -497,7 +498,7 @@ int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
                         goto out;
         }
 
-        chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
+        chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
 
         /* Not specified by any standard per-se, however it breaks too
          * many applications when removed.  It is unfortunate since
@@ -517,7 +518,8 @@ int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 
         snum = ntohs(addr->sin_port);
         err = -EACCES;
-        if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+        if (snum && snum < PROT_SOCK &&
+            !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
                 goto out;
 
         /*      We keep a pair of addresses. rcv_saddr is the one