2 files changed, 75 insertions, 9 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 074cf3e91c6f..f29b63fad932 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1091,8 +1091,10 @@ static void netlink_remove(struct sock *sk)
 	mutex_unlock(&nl_sk_hash_lock);
 
 	netlink_table_grab();
-	if (nlk_sk(sk)->subscriptions)
+	if (nlk_sk(sk)->subscriptions) {
 		__sk_del_bind_node(sk);
+		netlink_update_listeners(sk);
+	}
 	netlink_table_ungrab();
 }
 
@@ -1226,8 +1228,8 @@ static int netlink_release(struct socket *sock)
 
 	module_put(nlk->module);
 
-	netlink_table_grab();
 	if (netlink_is_kernel(sk)) {
+		netlink_table_grab();
 		BUG_ON(nl_table[sk->sk_protocol].registered == 0);
 		if (--nl_table[sk->sk_protocol].registered == 0) {
 			struct listeners *old;
@@ -1241,11 +1243,16 @@ static int netlink_release(struct socket *sock)
 			nl_table[sk->sk_protocol].flags = 0;
 			nl_table[sk->sk_protocol].registered = 0;
 		}
-	} else if (nlk->subscriptions) {
-		netlink_update_listeners(sk);
+		netlink_table_ungrab();
 	}
-	netlink_table_ungrab();
 
+	if (nlk->netlink_unbind) {
+		int i;
+
+		for (i = 0; i < nlk->ngroups; i++)
+			if (test_bit(i, nlk->groups))
+				nlk->netlink_unbind(i + 1);
+	}
 	kfree(nlk->groups);
 	nlk->groups = NULL;
 
@@ -1410,8 +1417,8 @@ static int netlink_realloc_groups(struct sock *sk)
 	return err;
 }
 
-static void netlink_unbind(int group, long unsigned int groups,
-			   struct netlink_sock *nlk)
+static void netlink_undo_bind(int group, long unsigned int groups,
+			      struct netlink_sock *nlk)
 {
 	int undo;
 
@@ -1461,7 +1468,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 			err = nlk->netlink_bind(group);
 			if (!err)
 				continue;
-			netlink_unbind(group, groups, nlk);
+			netlink_undo_bind(group, groups, nlk);
 			return err;
 		}
 	}
@@ -1471,7 +1478,7 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr,
 			netlink_insert(sk, net, nladdr->nl_pid) :
 			netlink_autobind(sock);
 		if (err) {
-			netlink_unbind(nlk->ngroups, groups, nlk);
+			netlink_undo_bind(nlk->ngroups, groups, nlk);
 			return err;
 		}
 	}
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 76393f2f4b22..05bf40bbd189 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -983,11 +983,70 @@ static struct genl_multicast_group genl_ctrl_groups[] = {
 	{ .name = "notify", },
 };
 
+static int genl_bind(int group)
+{
+	int i, err;
+	bool found = false;
+
+	down_read(&cb_lock);
+	for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
+		struct genl_family *f;
+
+		list_for_each_entry(f, genl_family_chain(i), family_list) {
+			if (group >= f->mcgrp_offset &&
+			    group < f->mcgrp_offset + f->n_mcgrps) {
+				int fam_grp = group - f->mcgrp_offset;
+
+				if (f->mcast_bind)
+					err = f->mcast_bind(fam_grp);
+				else
+					err = 0;
+				found = true;
+				break;
+			}
+		}
+	}
+	up_read(&cb_lock);
+
+	if (WARN_ON(!found))
+		err = 0;
+
+	return err;
+}
+
+static void genl_unbind(int group)
+{
+	int i;
+	bool found = false;
+
+	down_read(&cb_lock);
+	for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
+		struct genl_family *f;
+
+		list_for_each_entry(f, genl_family_chain(i), family_list) {
+			if (group >= f->mcgrp_offset &&
+			    group < f->mcgrp_offset + f->n_mcgrps) {
+				int fam_grp = group - f->mcgrp_offset;
+
+				if (f->mcast_unbind)
+					f->mcast_unbind(fam_grp);
+				found = true;
+				break;
+			}
+		}
+	}
+	up_read(&cb_lock);
+
+	WARN_ON(!found);
+}
+
 static int __net_init genl_pernet_init(struct net *net)
 {
 	struct netlink_kernel_cfg cfg = {
 		.input		= genl_rcv,
 		.flags		= NL_CFG_F_NONROOT_RECV,
+		.bind		= genl_bind,
+		.unbind		= genl_unbind,
 	};
 
 	/* we'll bump the group number right afterwards */