Re: [syzbot] [rdma] general protection fault in kernel_sock_shutdown (4)

[Edward Adam Davis <eadavis@qq.com>]

#syz test

diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
index 50a2cb5405e2..92847e955ca2 100644
--- a/drivers/infiniband/sw/rxe/rxe_net.c
+++ b/drivers/infiniband/sw/rxe/rxe_net.c
@@ -642,6 +642,8 @@ static void rxe_sock_put(struct sock *sk,
 	}
 }
 
+static DEFINE_MUTEX(rxe_net_del_mutex);
+
 void rxe_net_del(struct ib_device *dev)
 {
 	struct rxe_dev *rxe = container_of(dev, struct rxe_dev, ib_dev);
@@ -649,9 +651,10 @@ void rxe_net_del(struct ib_device *dev)
 	struct sock *sk;
 	struct net *net;
 
+	mutex_lock(&rxe_net_del_mutex);
 	ndev = rxe_ib_device_get_netdev(&rxe->ib_dev);
 	if (!ndev)
-		return;
+		goto out;
 
 	net = dev_net(ndev);
 
@@ -664,6 +667,8 @@ void rxe_net_del(struct ib_device *dev)
 		rxe_sock_put(sk, rxe_ns_pernet_set_sk6, net);
 
 	dev_put(ndev);
+out:
+	mutex_unlock(&rxe_net_del_mutex);
 }
 
 static void rxe_port_event(struct rxe_dev *rxe,