l2tp: take reference on sessions being dumped

[pandora-kernel.git] / net / l2tp / l2tp_netlink.c

diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c
index 93a41a0..6fd6322 100644 (file)
--- a/net/l2tp/l2tp_netlink.c
+++ b/net/l2tp/l2tp_netlink.c
@@ -40,7 +40,8 @@ static struct genl_family l2tp_nl_family = {
 /* Accessed under genl lock */
 static const struct l2tp_nl_cmd_ops *l2tp_nl_cmd_ops[__L2TP_PWTYPE_MAX];
 
-static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
+static struct l2tp_session *l2tp_nl_session_get(struct genl_info *info,
+                                               bool do_ref)
 {
        u32 tunnel_id;
        u32 session_id;
@@ -51,14 +52,15 @@ static struct l2tp_session *l2tp_nl_session_find(struct genl_info *info)
 
        if (info->attrs[L2TP_ATTR_IFNAME]) {
                ifname = nla_data(info->attrs[L2TP_ATTR_IFNAME]);
-               session = l2tp_session_find_by_ifname(net, ifname);
+               session = l2tp_session_get_by_ifname(net, ifname, do_ref);
        } else if ((info->attrs[L2TP_ATTR_SESSION_ID]) &&
                   (info->attrs[L2TP_ATTR_CONN_ID])) {
                tunnel_id = nla_get_u32(info->attrs[L2TP_ATTR_CONN_ID]);
                session_id = nla_get_u32(info->attrs[L2TP_ATTR_SESSION_ID]);
                tunnel = l2tp_tunnel_find(net, tunnel_id);
                if (tunnel)
-                       session = l2tp_session_find(net, tunnel, session_id);
+                       session = l2tp_session_get(net, tunnel, session_id,
+                                                  do_ref);
        }
 
        return session;
@@ -495,7 +497,7 @@ static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *inf
        struct l2tp_session *session;
        u16 pw_type;
 
-       session = l2tp_nl_session_find(info);
+       session = l2tp_nl_session_get(info, true);
        if (session == NULL) {
                ret = -ENODEV;
                goto out;
@@ -506,6 +508,10 @@ static int l2tp_nl_cmd_session_delete(struct sk_buff *skb, struct genl_info *inf
                if (l2tp_nl_cmd_ops[pw_type] && l2tp_nl_cmd_ops[pw_type]->session_delete)
                        ret = (*l2tp_nl_cmd_ops[pw_type]->session_delete)(session);
 
+       if (session->deref)
+               session->deref(session);
+       l2tp_session_dec_refcount(session);
+
 out:
        return ret;
 }
@@ -515,7 +521,7 @@ static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *inf
        int ret = 0;
        struct l2tp_session *session;
 
-       session = l2tp_nl_session_find(info);
+       session = l2tp_nl_session_get(info, false);
        if (session == NULL) {
                ret = -ENODEV;
                goto out;
@@ -545,6 +551,8 @@ static int l2tp_nl_cmd_session_modify(struct sk_buff *skb, struct genl_info *inf
        if (info->attrs[L2TP_ATTR_MRU])
                session->mru = nla_get_u16(info->attrs[L2TP_ATTR_MRU]);
 
+       l2tp_session_dec_refcount(session);
+
 out:
        return ret;
 }
@@ -615,29 +623,34 @@ static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info)
        struct sk_buff *msg;
        int ret;
 
-       session = l2tp_nl_session_find(info);
+       session = l2tp_nl_session_get(info, false);
        if (session == NULL) {
                ret = -ENODEV;
-               goto out;
+               goto err;
        }
 
        msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
        if (!msg) {
                ret = -ENOMEM;
-               goto out;
+               goto err_ref;
        }
 
        ret = l2tp_nl_session_send(msg, info->snd_pid, info->snd_seq,
                                   0, session);
        if (ret < 0)
-               goto err_out;
+               goto err_ref_msg;
 
-       return genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
+       ret = genlmsg_unicast(genl_info_net(info), msg, info->snd_pid);
 
-err_out:
-       nlmsg_free(msg);
+       l2tp_session_dec_refcount(session);
 
-out:
+       return ret;
+
+err_ref_msg:
+       nlmsg_free(msg);
+err_ref:
+       l2tp_session_dec_refcount(session);
+err:
        return ret;
 }
 
@@ -656,7 +669,7 @@ static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback
                                goto out;
                }
 
-               session = l2tp_session_find_nth(tunnel, si);
+               session = l2tp_session_get_nth(tunnel, si, false);
                if (session == NULL) {
                        ti++;
                        tunnel = NULL;
@@ -666,8 +679,11 @@ static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback
 
                if (l2tp_nl_session_send(skb, NETLINK_CB(cb->skb).pid,
                                         cb->nlh->nlmsg_seq, NLM_F_MULTI,
-                                        session) <= 0)
+                                        session) <= 0) {
+                       l2tp_session_dec_refcount(session);
                        break;
+               }
+               l2tp_session_dec_refcount(session);
 
                si++;
        }