netns: notify new nsid outside __peernet2id()

[cascardo/linux.git] / net / core / net_namespace.c

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 78fc04a..ee86424 100644 (file)
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -147,11 +147,9 @@ static void ops_free_list(const struct pernet_operations *ops,
        }
 }
 
-static void rtnl_net_notifyid(struct net *net, struct net *peer, int cmd,
-                             int id);
 static int alloc_netid(struct net *net, struct net *peer, int reqid)
 {
-       int min = 0, max = 0, id;
+       int min = 0, max = 0;
 
        ASSERT_RTNL();
 
@@ -160,11 +158,7 @@ static int alloc_netid(struct net *net, struct net *peer, int reqid)
                max = reqid + 1;
        }
 
-       id = idr_alloc(&net->netns_ids, peer, min, max, GFP_KERNEL);
-       if (id >= 0)
-               rtnl_net_notifyid(net, peer, RTM_NEWNSID, id);
-
-       return id;
+       return idr_alloc(&net->netns_ids, peer, min, max, GFP_KERNEL);
 }
 
 /* This function is used by idr_for_each(). If net is equal to peer, the
@@ -180,36 +174,52 @@ static int net_eq_idr(int id, void *net, void *peer)
        return 0;
 }
 
-static int __peernet2id(struct net *net, struct net *peer, bool alloc)
+static int __peernet2id_alloc(struct net *net, struct net *peer, bool *alloc)
 {
        int id = idr_for_each(&net->netns_ids, net_eq_idr, peer);
+       bool alloc_it = *alloc;
 
        ASSERT_RTNL();
 
+       *alloc = false;
+
        /* Magic value for id 0. */
        if (id == NET_ID_ZERO)
                return 0;
        if (id > 0)
                return id;
 
-       if (alloc)
-               return alloc_netid(net, peer, -1);
+       if (alloc_it) {
+               id = alloc_netid(net, peer, -1);
+               *alloc = true;
+               return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
+       }
+
+       return NETNSA_NSID_NOT_ASSIGNED;
+}
+
+static int __peernet2id(struct net *net, struct net *peer)
+{
+       bool no = false;
 
-       return -ENOENT;
+       return __peernet2id_alloc(net, peer, &no);
 }
 
+static void rtnl_net_notifyid(struct net *net, int cmd, int id);
 /* This function returns the id of a peer netns. If no id is assigned, one will
  * be allocated and returned.
  */
-int peernet2id(struct net *net, struct net *peer)
+int peernet2id_alloc(struct net *net, struct net *peer)
 {
        bool alloc = atomic_read(&peer->count) == 0 ? false : true;
        int id;
 
-       id = __peernet2id(net, peer, alloc);
-       return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
+       id = __peernet2id_alloc(net, peer, &alloc);
+       if (alloc && id >= 0)
+               rtnl_net_notifyid(net, RTM_NEWNSID, id);
+       return id;
 }
-EXPORT_SYMBOL(peernet2id);
+EXPORT_SYMBOL(peernet2id_alloc);
 
 struct net *get_net_ns_by_id(struct net *net, int id)
 {
@@ -362,10 +372,10 @@ static void cleanup_net(struct work_struct *work)
                list_del_rcu(&net->list);
                list_add_tail(&net->exit_list, &net_exit_list);
                for_each_net(tmp) {
-                       int id = __peernet2id(tmp, net, false);
+                       int id = __peernet2id(tmp, net);
 
                        if (id >= 0) {
-                               rtnl_net_notifyid(tmp, net, RTM_DELNSID, id);
+                               rtnl_net_notifyid(tmp, RTM_DELNSID, id);
                                idr_remove(&tmp->netns_ids, id);
                        }
                }
@@ -517,14 +527,16 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh)
        if (IS_ERR(peer))
                return PTR_ERR(peer);
 
-       if (__peernet2id(net, peer, false) >= 0) {
+       if (__peernet2id(net, peer) >= 0) {
                err = -EEXIST;
                goto out;
        }
 
        err = alloc_netid(net, peer, nsid);
-       if (err > 0)
+       if (err >= 0) {
+               rtnl_net_notifyid(net, RTM_NEWNSID, err);
                err = 0;
+       }
 out:
        put_net(peer);
        return err;
@@ -538,14 +550,10 @@ static int rtnl_net_get_size(void)
 }
 
 static int rtnl_net_fill(struct sk_buff *skb, u32 portid, u32 seq, int flags,
-                        int cmd, struct net *net, struct net *peer,
-                        int nsid)
+                        int cmd, struct net *net, int nsid)
 {
        struct nlmsghdr *nlh;
        struct rtgenmsg *rth;
-       int id;
-
-       ASSERT_RTNL();
 
        nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rth), flags);
        if (!nlh)
@@ -554,14 +562,7 @@ static int rtnl_net_fill(struct sk_buff *skb, u32 portid, u32 seq, int flags,
        rth = nlmsg_data(nlh);
        rth->rtgen_family = AF_UNSPEC;
 
-       if (nsid >= 0) {
-               id = nsid;
-       } else {
-               id = __peernet2id(net, peer, false);
-               if  (id < 0)
-                       id = NETNSA_NSID_NOT_ASSIGNED;
-       }
-       if (nla_put_s32(skb, NETNSA_NSID, id))
+       if (nla_put_s32(skb, NETNSA_NSID, nsid))
                goto nla_put_failure;
 
        nlmsg_end(skb, nlh);
@@ -578,7 +579,7 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh)
        struct nlattr *tb[NETNSA_MAX + 1];
        struct sk_buff *msg;
        struct net *peer;
-       int err;
+       int err, id;
 
        err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
                          rtnl_net_policy);
@@ -600,8 +601,9 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh)
                goto out;
        }
 
+       id = __peernet2id(net, peer);
        err = rtnl_net_fill(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
-                           RTM_GETNSID, net, peer, -1);
+                           RTM_GETNSID, net, id);
        if (err < 0)
                goto err_out;
 
@@ -633,7 +635,7 @@ static int rtnl_net_dumpid_one(int id, void *peer, void *data)
 
        ret = rtnl_net_fill(net_cb->skb, NETLINK_CB(net_cb->cb->skb).portid,
                            net_cb->cb->nlh->nlmsg_seq, NLM_F_MULTI,
-                           RTM_NEWNSID, net_cb->net, peer, id);
+                           RTM_NEWNSID, net_cb->net, id);
        if (ret < 0)
                return ret;
 
@@ -661,8 +663,7 @@ static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb)
        return skb->len;
 }
 
-static void rtnl_net_notifyid(struct net *net, struct net *peer, int cmd,
-                             int id)
+static void rtnl_net_notifyid(struct net *net, int cmd, int id)
 {
        struct sk_buff *msg;
        int err = -ENOMEM;
@@ -671,7 +672,7 @@ static void rtnl_net_notifyid(struct net *net, struct net *peer, int cmd,
        if (!msg)
                goto out;
 
-       err = rtnl_net_fill(msg, 0, 0, 0, cmd, net, peer, id);
+       err = rtnl_net_fill(msg, 0, 0, 0, cmd, net, id);
        if (err < 0)
                goto err_out;