1 files changed, 37 insertions, 7 deletions

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index abb0c70ffc8b..3de9350cbf30 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -132,8 +132,8 @@ static int service_announce_new(struct sockaddr_qrtr *dest,
 	return kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
 }
 
-static int service_announce_del(struct sockaddr_qrtr *dest,
-				struct qrtr_server *srv)
+static void service_announce_del(struct sockaddr_qrtr *dest,
+				 struct qrtr_server *srv)
 {
 	struct qrtr_ctrl_pkt pkt;
 	struct msghdr msg = { };
@@ -157,10 +157,10 @@ static int service_announce_del(struct sockaddr_qrtr *dest,
 	msg.msg_namelen = sizeof(*dest);
 
 	ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
-	if (ret < 0)
+	if (ret < 0 && ret != -ENODEV)
 		pr_err("failed to announce del service\n");
 
-	return ret;
+	return;
 }
 
 static void lookup_notify(struct sockaddr_qrtr *to, struct qrtr_server *srv,
@@ -188,7 +188,7 @@ static void lookup_notify(struct sockaddr_qrtr *to, struct qrtr_server *srv,
 	msg.msg_namelen = sizeof(*to);
 
 	ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
-	if (ret < 0)
+	if (ret < 0 && ret != -ENODEV)
 		pr_err("failed to send lookup notification\n");
 }
 
@@ -207,6 +207,9 @@ static int announce_servers(struct sockaddr_qrtr *sq)
 	xa_for_each(&node->servers, index, srv) {
 		ret = service_announce_new(sq, srv);
 		if (ret < 0) {
+			if (ret == -ENODEV)
+				continue;
+
 			pr_err("failed to announce new service\n");
 			return ret;
 		}
@@ -369,7 +372,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
 		msg.msg_namelen = sizeof(sq);
 
 		ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
-		if (ret < 0) {
+		if (ret < 0 && ret != -ENODEV) {
 			pr_err("failed to send bye cmd\n");
 			return ret;
 		}
@@ -443,7 +446,7 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
 		msg.msg_namelen = sizeof(sq);
 
 		ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
-		if (ret < 0) {
+		if (ret < 0 && ret != -ENODEV) {
 			pr_err("failed to send del client cmd\n");
 			return ret;
 		}
@@ -725,6 +728,24 @@ int qrtr_ns_init(void)
 	if (ret < 0)
 		goto err_wq;
 
+	/* As the qrtr ns socket owner and creator is the same module, we have
+	 * to decrease the qrtr module reference count to guarantee that it
+	 * remains zero after the ns socket is created, otherwise, executing
+	 * "rmmod" command is unable to make the qrtr module deleted after the
+	 *  qrtr module is inserted successfully.
+	 *
+	 * However, the reference count is increased twice in
+	 * sock_create_kern(): one is to increase the reference count of owner
+	 * of qrtr socket's proto_ops struct; another is to increment the
+	 * reference count of owner of qrtr proto struct. Therefore, we must
+	 * decrement the module reference count twice to ensure that it keeps
+	 * zero after server's listening socket is created. Of course, we
+	 * must bump the module reference count twice as well before the socket
+	 * is closed.
+	 */
+	module_put(qrtr_ns.sock->ops->owner);
+	module_put(qrtr_ns.sock->sk->sk_prot_creator->owner);
+
 	return 0;
 
 err_wq:
@@ -739,6 +760,15 @@ void qrtr_ns_remove(void)
 {
 	cancel_work_sync(&qrtr_ns.work);
 	destroy_workqueue(qrtr_ns.workqueue);
+
+	/* sock_release() expects the two references that were put during
+	 * qrtr_ns_init(). This function is only called during module remove,
+	 * so try_stop_module() has already set the refcnt to 0. Use
+	 * __module_get() instead of try_module_get() to successfully take two
+	 * references.
+	 */
+	__module_get(qrtr_ns.sock->ops->owner);
+	__module_get(qrtr_ns.sock->sk->sk_prot_creator->owner);
 	sock_release(qrtr_ns.sock);
 }
 EXPORT_SYMBOL_GPL(qrtr_ns_remove);