Adding upstream version 6.9.7.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index abb0c70ffc..654a3cc0d3 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -725,6 +725,24 @@ 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 +757,15 @@ 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);