tipc: fix modprobe tipc failed after switch order of device registration

Error message printed:
modprobe: ERROR: could not insert 'tipc': Address family not
supported by protocol.
when modprobe tipc after the following patch: switch order of
device registration, commit 7e27e8d6130c
("tipc: switch order of device registration to fix a crash")

Because sock_create_kern(net, AF_TIPC, ...) called by
tipc_topsrv_create_listener() in the initialization process
of tipc_init_net(), so tipc_socket_init() must be execute before that.
Meanwhile, tipc_net_id need to be initialized when sock_create()
called, and tipc_socket_init() is no need to be called for each namespace.

I add a variable tipc_topsrv_net_ops, and split the
register_pernet_subsys() of tipc into two parts, and split
tipc_socket_init() with initialization of pernet params.

By the way, I fixed resources rollback error when tipc_bcast_init()
failed in tipc_init_net().

Fixes: 7e27e8d6130c ("tipc: switch order of device registration to fix a crash")
Signed-off-by: Junwei Hu <hujunwei4@huawei.com>
Reported-by: Wang Wang <wangwang2@huawei.com>
Reported-by: syzbot+1e8114b61079bfe9cbc5@syzkaller.appspotmail.com
Reviewed-by: Kang Zhou <zhoukang7@huawei.com>
Reviewed-by: Suanming Mou <mousuanming@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 2 deletions

diff --git a/net/tipc/topsrv.c b/net/tipc/topsrv.c
index b45932d78004..f345662890a6 100644
--- a/net/tipc/topsrv.c
+++ b/net/tipc/topsrv.c
@@ -635,7 +635,7 @@ static void tipc_topsrv_work_stop(struct tipc_topsrv *s)
 	destroy_workqueue(s->send_wq);
 }
 
-int tipc_topsrv_start(struct net *net)
+static int tipc_topsrv_start(struct net *net)
 {
 	struct tipc_net *tn = tipc_net(net);
 	const char name[] = "topology_server";
@@ -668,7 +668,7 @@ int tipc_topsrv_start(struct net *net)
 	return ret;
 }
 
-void tipc_topsrv_stop(struct net *net)
+static void tipc_topsrv_stop(struct net *net)
 {
 	struct tipc_topsrv *srv = tipc_topsrv(net);
 	struct socket *lsock = srv->listener;
@@ -693,3 +693,13 @@ void tipc_topsrv_stop(struct net *net)
 	idr_destroy(&srv->conn_idr);
 	kfree(srv);
 }
+
+int __net_init tipc_topsrv_init_net(struct net *net)
+{
+	return tipc_topsrv_start(net);
+}
+
+void __net_exit tipc_topsrv_exit_net(struct net *net)
+{
+	tipc_topsrv_stop(net);
+}