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, 5 insertions, 3 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 15379acd9c08..2e897069310a 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -335,6 +335,7 @@ static struct sctp_af *sctp_sockaddr_af(struct sctp_sock *opt,
 /* Bind a local address either to an endpoint or to an association.  */
 SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
 {
+        struct net *net = sock_net(sk);
         struct sctp_sock *sp = sctp_sk(sk);
         struct sctp_endpoint *ep = sp->ep;
         struct sctp_bind_addr *bp = &ep->base.bind_addr;
@@ -378,7 +379,8 @@ SCTP_STATIC int sctp_do_bind(struct sock *sk, union sctp_addr *addr, int len)
                 }
         }
 
-        if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+        if (snum && snum < PROT_SOCK &&
+            !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
                 return -EACCES;
 
         /* See if the address matches any of the addresses we may have
@@ -1161,7 +1163,7 @@ static int __sctp_connect(struct sock* sk,
                                  * be permitted to open new associations.
                                  */
                                 if (ep->base.bind_addr.port < PROT_SOCK &&
-                                    !capable(CAP_NET_BIND_SERVICE)) {
+                                    !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
                                         err = -EACCES;
                                         goto out_free;
                                 }
@@ -1790,7 +1792,7 @@ SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
                          * associations.
                          */
                         if (ep->base.bind_addr.port < PROT_SOCK &&
-                            !capable(CAP_NET_BIND_SERVICE)) {
+                            !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE)) {
                                 err = -EACCES;
                                 goto out_unlock;
                         }