4 files changed, 57 insertions, 8 deletions

diff --git a/fs/smb/server/mgmt/tree_connect.c b/fs/smb/server/mgmt/tree_connect.c
index 408cddf2f094..d2c81a8a11dd 100644
--- a/fs/smb/server/mgmt/tree_connect.c
+++ b/fs/smb/server/mgmt/tree_connect.c
@@ -73,7 +73,10 @@ ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 
 	tree_conn->user = sess->user;
 	tree_conn->share_conf = sc;
+	tree_conn->t_state = TREE_NEW;
 	status.tree_conn = tree_conn;
+	atomic_set(&tree_conn->refcount, 1);
+	init_waitqueue_head(&tree_conn->refcount_q);
 
 	ret = xa_err(xa_store(&sess->tree_conns, tree_conn->id, tree_conn,
 			      GFP_KERNEL));
@@ -93,14 +96,33 @@ out_error:
 	return status;
 }
 
+void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon)
+{
+	/*
+	 * Checking waitqueue to releasing tree connect on
+	 * tree disconnect. waitqueue_active is safe because it
+	 * uses atomic operation for condition.
+	 */
+	if (!atomic_dec_return(&tcon->refcount) &&
+	    waitqueue_active(&tcon->refcount_q))
+		wake_up(&tcon->refcount_q);
+}
+
 int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
 			       struct ksmbd_tree_connect *tree_conn)
 {
 	int ret;
 
+	write_lock(&sess->tree_conns_lock);
+	xa_erase(&sess->tree_conns, tree_conn->id);
+	write_unlock(&sess->tree_conns_lock);
+
+	if (!atomic_dec_and_test(&tree_conn->refcount))
+		wait_event(tree_conn->refcount_q,
+			   atomic_read(&tree_conn->refcount) == 0);
+
 	ret = ksmbd_ipc_tree_disconnect_request(sess->id, tree_conn->id);
 	ksmbd_release_tree_conn_id(sess, tree_conn->id);
-	xa_erase(&sess->tree_conns, tree_conn->id);
 	ksmbd_share_config_put(tree_conn->share_conf);
 	kfree(tree_conn);
 	return ret;
@@ -111,11 +133,15 @@ struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess,
 {
 	struct ksmbd_tree_connect *tcon;
 
+	read_lock(&sess->tree_conns_lock);
 	tcon = xa_load(&sess->tree_conns, id);
 	if (tcon) {
-		if (test_bit(TREE_CONN_EXPIRE, &tcon->status))
+		if (tcon->t_state != TREE_CONNECTED)
+			tcon = NULL;
+		else if (!atomic_inc_not_zero(&tcon->refcount))
 			tcon = NULL;
 	}
+	read_unlock(&sess->tree_conns_lock);
 
 	return tcon;
 }
@@ -129,8 +155,18 @@ int ksmbd_tree_conn_session_logoff(struct ksmbd_session *sess)
 	if (!sess)
 		return -EINVAL;
 
-	xa_for_each(&sess->tree_conns, id, tc)
+	xa_for_each(&sess->tree_conns, id, tc) {
+		write_lock(&sess->tree_conns_lock);
+		if (tc->t_state == TREE_DISCONNECTED) {
+			write_unlock(&sess->tree_conns_lock);
+			ret = -ENOENT;
+			continue;
+		}
+		tc->t_state = TREE_DISCONNECTED;
+		write_unlock(&sess->tree_conns_lock);
+
 		ret |= ksmbd_tree_conn_disconnect(sess, tc);
+	}
 	xa_destroy(&sess->tree_conns);
 	return ret;
 }
diff --git a/fs/smb/server/mgmt/tree_connect.h b/fs/smb/server/mgmt/tree_connect.h
index 562d647ad9fa..6377a70b811c 100644
--- a/fs/smb/server/mgmt/tree_connect.h
+++ b/fs/smb/server/mgmt/tree_connect.h
@@ -14,7 +14,11 @@ struct ksmbd_share_config;
 struct ksmbd_user;
 struct ksmbd_conn;
 
-#define TREE_CONN_EXPIRE		1
+enum {
+	TREE_NEW = 0,
+	TREE_CONNECTED,
+	TREE_DISCONNECTED
+};
 
 struct ksmbd_tree_connect {
 	int				id;
@@ -27,7 +31,9 @@ struct ksmbd_tree_connect {
 
 	int				maximal_access;
 	bool				posix_extensions;
-	unsigned long			status;
+	atomic_t			refcount;
+	wait_queue_head_t		refcount_q;
+	unsigned int			t_state;
 };
 
 struct ksmbd_tree_conn_status {
@@ -46,6 +52,7 @@ struct ksmbd_session;
 struct ksmbd_tree_conn_status
 ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 			const char *share_name);
+void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon);
 
 int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
 			       struct ksmbd_tree_connect *tree_conn);
diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c
index 8a5dcab05614..15f68ee05089 100644
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -174,7 +174,7 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn)
 	unsigned long id;
 	struct ksmbd_session *sess;
 
-	down_write(&sessions_table_lock);
+	down_write(&conn->session_lock);
 	xa_for_each(&conn->sessions, id, sess) {
 		if (sess->state != SMB2_SESSION_VALID ||
 		    time_after(jiffies,
@@ -185,7 +185,7 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn)
 			continue;
 		}
 	}
-	up_write(&sessions_table_lock);
+	up_write(&conn->session_lock);
 }
 
 int ksmbd_session_register(struct ksmbd_conn *conn,
@@ -227,7 +227,9 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 			}
 		}
 	}
+	up_write(&sessions_table_lock);
 
+	down_write(&conn->session_lock);
 	xa_for_each(&conn->sessions, id, sess) {
 		unsigned long chann_id;
 		struct channel *chann;
@@ -244,7 +246,7 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 			ksmbd_session_destroy(sess);
 		}
 	}
-	up_write(&sessions_table_lock);
+	up_write(&conn->session_lock);
 }
 
 struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
@@ -252,9 +254,11 @@ struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
 {
 	struct ksmbd_session *sess;
 
+	down_read(&conn->session_lock);
 	sess = xa_load(&conn->sessions, id);
 	if (sess)
 		sess->last_active = jiffies;
+	up_read(&conn->session_lock);
 	return sess;
 }
 
@@ -351,6 +355,7 @@ static struct ksmbd_session *__session_create(int protocol)
 	xa_init(&sess->ksmbd_chann_list);
 	xa_init(&sess->rpc_handle_list);
 	sess->sequence_number = 1;
+	rwlock_init(&sess->tree_conns_lock);
 
 	ret = __init_smb2_session(sess);
 	if (ret)
diff --git a/fs/smb/server/mgmt/user_session.h b/fs/smb/server/mgmt/user_session.h
index f99d475b28db..63cb08fffde8 100644
--- a/fs/smb/server/mgmt/user_session.h
+++ b/fs/smb/server/mgmt/user_session.h
@@ -60,6 +60,7 @@ struct ksmbd_session {
 
 	struct ksmbd_file_table		file_table;
 	unsigned long			last_active;
+	rwlock_t			tree_conns_lock;
 };
 
 static inline int test_session_flag(struct ksmbd_session *sess, int bit)