Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / net / netlink / af_netlink.c

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index c9c2a8441d32d70b26979850951e66d0888bc09e..5ed562dfe743d6febc6d4b83598d2a430bf4387b 100644 (file)
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -500,7 +500,7 @@ static unsigned int netlink_poll(struct file *file, struct socket *sock,
                while (nlk->cb != NULL && netlink_dump_space(nlk)) {
                        err = netlink_dump(sk);
                        if (err < 0) {
-                               sk->sk_err = err;
+                               sk->sk_err = -err;
                                sk->sk_error_report(sk);
                                break;
                        }
@@ -1219,7 +1219,74 @@ retry:
        return err;
 }
 
-static inline int netlink_capable(const struct socket *sock, unsigned int flag)
+/**
+ * __netlink_ns_capable - General netlink message capability test
+ * @nsp: NETLINK_CB of the socket buffer holding a netlink command from userspace.
+ * @user_ns: The user namespace of the capability to use
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in the user namespace @user_ns.
+ */
+bool __netlink_ns_capable(const struct netlink_skb_parms *nsp,
+                       struct user_namespace *user_ns, int cap)
+{
+       return ((nsp->flags & NETLINK_SKB_DST) ||
+               file_ns_capable(nsp->sk->sk_socket->file, user_ns, cap)) &&
+               ns_capable(user_ns, cap);
+}
+EXPORT_SYMBOL(__netlink_ns_capable);
+
+/**
+ * netlink_ns_capable - General netlink message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @user_ns: The user namespace of the capability to use
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in the user namespace @user_ns.
+ */
+bool netlink_ns_capable(const struct sk_buff *skb,
+                       struct user_namespace *user_ns, int cap)
+{
+       return __netlink_ns_capable(&NETLINK_CB(skb), user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_ns_capable);
+
+/**
+ * netlink_capable - Netlink global message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap in all user namespaces.
+ */
+bool netlink_capable(const struct sk_buff *skb, int cap)
+{
+       return netlink_ns_capable(skb, &init_user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_capable);
+
+/**
+ * netlink_net_capable - Netlink network namespace message capability test
+ * @skb: socket buffer holding a netlink command from userspace
+ * @cap: The capability to use
+ *
+ * Test to see if the opener of the socket we received the message
+ * from had when the netlink socket was created and the sender of the
+ * message has has the capability @cap over the network namespace of
+ * the socket we received the message from.
+ */
+bool netlink_net_capable(const struct sk_buff *skb, int cap)
+{
+       return netlink_ns_capable(skb, sock_net(skb->sk)->user_ns, cap);
+}
+EXPORT_SYMBOL(netlink_net_capable);
+
+static inline int netlink_allowed(const struct socket *sock, unsigned int flag)
 {
        return (nl_table[sock->sk->sk_protocol].flags & flag) ||
                ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN);
@@ -1287,7 +1354,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 
        /* Only superuser is allowed to listen multicasts */
        if (nladdr->nl_groups) {
-               if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
+               if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV))
                        return -EPERM;
                err = netlink_realloc_groups(sk);
                if (err)
@@ -1349,7 +1416,7 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,
                return -EINVAL;
 
        /* Only superuser is allowed to send multicasts */
-       if (nladdr->nl_groups && !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
+       if (nladdr->nl_groups && !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
                return -EPERM;
 
        if (!nlk->portid)
@@ -1921,7 +1988,7 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
                break;
        case NETLINK_ADD_MEMBERSHIP:
        case NETLINK_DROP_MEMBERSHIP: {
-               if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
+               if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV))
                        return -EPERM;
                err = netlink_realloc_groups(sk);
                if (err)
@@ -2053,6 +2120,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
        struct sk_buff *skb;
        int err;
        struct scm_cookie scm;
+       u32 netlink_skb_flags = 0;
 
        if (msg->msg_flags&MSG_OOB)
                return -EOPNOTSUPP;
@@ -2072,8 +2140,9 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
                dst_group = ffs(addr->nl_groups);
                err =  -EPERM;
                if ((dst_group || dst_portid) &&
-                   !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
+                   !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
                        goto out;
+               netlink_skb_flags |= NETLINK_SKB_DST;
        } else {
                dst_portid = nlk->dst_portid;
                dst_group = nlk->dst_group;
@@ -2103,6 +2172,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
        NETLINK_CB(skb).portid  = nlk->portid;
        NETLINK_CB(skb).dst_group = dst_group;
        NETLINK_CB(skb).creds   = siocb->scm->creds;
+       NETLINK_CB(skb).flags   = netlink_skb_flags;
 
        err = -EFAULT;
        if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
@@ -2202,7 +2272,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
        if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
                ret = netlink_dump(sk);
                if (ret) {
-                       sk->sk_err = ret;
+                       sk->sk_err = -ret;
                        sk->sk_error_report(sk);
                }
        }