Merge tag '6.4-rc-ksmbd-server-fixes-part2' of git://git.samba.org/ksmbd

Pull ksmbd server fixes from Steve French:
 "Ten ksmbd server fixes, including some important security fixes:

   - Two use after free fixes

   - Fix RCU callback race

   - Deadlock fix

   - Three patches to prevent session setup attacks

   - Prevent guest users from establishing multichannel sessions

   - Fix null pointer dereference in query FS info

   - Memleak fix"

* tag '6.4-rc-ksmbd-server-fixes-part2' of git://git.samba.org/ksmbd:
  ksmbd: call rcu_barrier() in ksmbd_server_exit()
  ksmbd: fix racy issue under cocurrent smb2 tree disconnect
  ksmbd: fix racy issue from smb2 close and logoff with multichannel
  ksmbd: not allow guest user on multichannel
  ksmbd: fix deadlock in ksmbd_find_crypto_ctx()
  ksmbd: block asynchronous requests when making a delay on session setup
  ksmbd: destroy expired sessions
  ksmbd: fix racy issue from session setup and logoff
  ksmbd: fix NULL pointer dereference in smb2_get_info_filesystem()
  ksmbd: fix memleak in session setup

fs/ksmbd/auth.c

@@ -221,22 +221,22 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 {
 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
-	struct ksmbd_crypto_ctx *ctx;
+	struct ksmbd_crypto_ctx *ctx = NULL;
 	char *construct = NULL;
 	int rc, len;
 
-	ctx = ksmbd_crypto_ctx_find_hmacmd5();
-	if (!ctx) {
-		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
-		return -ENOMEM;
-	}
-
 	rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
 	if (rc) {
 		ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
 		goto out;
 	}
 
+	ctx = ksmbd_crypto_ctx_find_hmacmd5();
+	if (!ctx) {
+		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
+		return -ENOMEM;
+	}
+
 	rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
 				 ntlmv2_hash,
 				 CIFS_HMAC_MD5_HASH_SIZE);
@@ -272,6 +272,8 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 		ksmbd_debug(AUTH, "Could not generate md5 hash\n");
 		goto out;
 	}
+	ksmbd_release_crypto_ctx(ctx);
+	ctx = NULL;
 
 	rc = ksmbd_gen_sess_key(sess, ntlmv2_hash, ntlmv2_rsp);
 	if (rc) {
@@ -282,6 +284,7 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
 	if (memcmp(ntlmv2->ntlmv2_hash, ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE) != 0)
 		rc = -EINVAL;
 out:
+	if (ctx)
 		ksmbd_release_crypto_ctx(ctx);
 	kfree(construct);
 	return rc;

fs/ksmbd/connection.c

@@ -20,7 +20,7 @@ static DEFINE_MUTEX(init_lock);
 static struct ksmbd_conn_ops default_conn_ops;
 
 LIST_HEAD(conn_list);
-DEFINE_RWLOCK(conn_list_lock);
+DECLARE_RWSEM(conn_list_lock);
 
 /**
  * ksmbd_conn_free() - free resources of the connection instance
@@ -32,9 +32,9 @@ DEFINE_RWLOCK(conn_list_lock);
  */
 void ksmbd_conn_free(struct ksmbd_conn *conn)
 {
-	write_lock(&conn_list_lock);
+	down_write(&conn_list_lock);
 	list_del(&conn->conns_list);
-	write_unlock(&conn_list_lock);
+	up_write(&conn_list_lock);
 
 	xa_destroy(&conn->sessions);
 	kvfree(conn->request_buf);
@@ -56,7 +56,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 		return NULL;
 
 	conn->need_neg = true;
-	conn->status = KSMBD_SESS_NEW;
+	ksmbd_conn_set_new(conn);
 	conn->local_nls = load_nls("utf8");
 	if (!conn->local_nls)
 		conn->local_nls = load_nls_default();
@@ -84,9 +84,9 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
 	spin_lock_init(&conn->llist_lock);
 	INIT_LIST_HEAD(&conn->lock_list);
 
-	write_lock(&conn_list_lock);
+	down_write(&conn_list_lock);
 	list_add(&conn->conns_list, &conn_list);
-	write_unlock(&conn_list_lock);
+	up_write(&conn_list_lock);
 	return conn;
 }
 
@@ -95,7 +95,7 @@ bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c)
 	struct ksmbd_conn *t;
 	bool ret = false;
 
-	read_lock(&conn_list_lock);
+	down_read(&conn_list_lock);
 	list_for_each_entry(t, &conn_list, conns_list) {
 		if (memcmp(t->ClientGUID, c->ClientGUID, SMB2_CLIENT_GUID_SIZE))
 			continue;
@@ -103,7 +103,7 @@ bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c)
 		ret = true;
 		break;
 	}
-	read_unlock(&conn_list_lock);
+	up_read(&conn_list_lock);
 	return ret;
 }
 
@@ -147,19 +147,47 @@ int ksmbd_conn_try_dequeue_request(struct ksmbd_work *work)
 	return ret;
 }
 
-static void ksmbd_conn_lock(struct ksmbd_conn *conn)
+void ksmbd_conn_lock(struct ksmbd_conn *conn)
 {
 	mutex_lock(&conn->srv_mutex);
 }
 
-static void ksmbd_conn_unlock(struct ksmbd_conn *conn)
+void ksmbd_conn_unlock(struct ksmbd_conn *conn)
 {
 	mutex_unlock(&conn->srv_mutex);
 }
 
-void ksmbd_conn_wait_idle(struct ksmbd_conn *conn)
+void ksmbd_all_conn_set_status(u64 sess_id, u32 status)
 {
+	struct ksmbd_conn *conn;
+
+	down_read(&conn_list_lock);
+	list_for_each_entry(conn, &conn_list, conns_list) {
+		if (conn->binding || xa_load(&conn->sessions, sess_id))
+			WRITE_ONCE(conn->status, status);
+	}
+	up_read(&conn_list_lock);
+}
+
+void ksmbd_conn_wait_idle(struct ksmbd_conn *conn, u64 sess_id)
+{
+	struct ksmbd_conn *bind_conn;
+
 	wait_event(conn->req_running_q, atomic_read(&conn->req_running) < 2);
+
+	down_read(&conn_list_lock);
+	list_for_each_entry(bind_conn, &conn_list, conns_list) {
+		if (bind_conn == conn)
+			continue;
+
+		if ((bind_conn->binding || xa_load(&bind_conn->sessions, sess_id)) &&
+		    !ksmbd_conn_releasing(bind_conn) &&
+		    atomic_read(&bind_conn->req_running)) {
+			wait_event(bind_conn->req_running_q,
+				atomic_read(&bind_conn->req_running) == 0);
+		}
+	}
+	up_read(&conn_list_lock);
 }
 
 int ksmbd_conn_write(struct ksmbd_work *work)
@@ -243,7 +271,7 @@ bool ksmbd_conn_alive(struct ksmbd_conn *conn)
 	if (!ksmbd_server_running())
 		return false;
 
-	if (conn->status == KSMBD_SESS_EXITING)
+	if (ksmbd_conn_exiting(conn))
 		return false;
 
 	if (kthread_should_stop())
@@ -303,7 +331,7 @@ int ksmbd_conn_handler_loop(void *p)
 		pdu_size = get_rfc1002_len(hdr_buf);
 		ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size);
 
-		if (conn->status == KSMBD_SESS_GOOD)
+		if (ksmbd_conn_good(conn))
 			max_allowed_pdu_size =
 				SMB3_MAX_MSGSIZE + conn->vals->max_write_size;
 		else
@@ -312,7 +340,7 @@ int ksmbd_conn_handler_loop(void *p)
 		if (pdu_size > max_allowed_pdu_size) {
 			pr_err_ratelimited("PDU length(%u) exceeded maximum allowed pdu size(%u) on connection(%d)\n",
 					pdu_size, max_allowed_pdu_size,
-					conn->status);
+					READ_ONCE(conn->status));
 			break;
 		}
 
@@ -360,10 +388,10 @@ int ksmbd_conn_handler_loop(void *p)
 	}
 
 out:
+	ksmbd_conn_set_releasing(conn);
 	/* Wait till all reference dropped to the Server object*/
 	wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0);
 
-
 	if (IS_ENABLED(CONFIG_UNICODE))
 		utf8_unload(conn->um);
 	unload_nls(conn->local_nls);
@@ -407,7 +435,7 @@ static void stop_sessions(void)
 	struct ksmbd_transport *t;
 
 again:
-	read_lock(&conn_list_lock);
+	down_read(&conn_list_lock);
 	list_for_each_entry(conn, &conn_list, conns_list) {
 		struct task_struct *task;
 
@@ -416,14 +444,14 @@ static void stop_sessions(void)
 		if (task)
 			ksmbd_debug(CONN, "Stop session handler %s/%d\n",
 				    task->comm, task_pid_nr(task));
-		conn->status = KSMBD_SESS_EXITING;
+		ksmbd_conn_set_exiting(conn);
 		if (t->ops->shutdown) {
-			read_unlock(&conn_list_lock);
+			up_read(&conn_list_lock);
 			t->ops->shutdown(t);
-			read_lock(&conn_list_lock);
+			down_read(&conn_list_lock);
 		}
 	}
-	read_unlock(&conn_list_lock);
+	up_read(&conn_list_lock);
 
 	if (!list_empty(&conn_list)) {
 		schedule_timeout_interruptible(HZ / 10); /* 100ms */

fs/ksmbd/connection.h

@@ -26,7 +26,8 @@ enum {
 	KSMBD_SESS_GOOD,
 	KSMBD_SESS_EXITING,
 	KSMBD_SESS_NEED_RECONNECT,
-	KSMBD_SESS_NEED_NEGOTIATE
+	KSMBD_SESS_NEED_NEGOTIATE,
+	KSMBD_SESS_RELEASING
 };
 
 struct ksmbd_stats {
@@ -140,10 +141,10 @@ struct ksmbd_transport {
 #define KSMBD_TCP_PEER_SOCKADDR(c)	((struct sockaddr *)&((c)->peer_addr))
 
 extern struct list_head conn_list;
-extern rwlock_t conn_list_lock;
+extern struct rw_semaphore conn_list_lock;
 
 bool ksmbd_conn_alive(struct ksmbd_conn *conn);
-void ksmbd_conn_wait_idle(struct ksmbd_conn *conn);
+void ksmbd_conn_wait_idle(struct ksmbd_conn *conn, u64 sess_id);
 struct ksmbd_conn *ksmbd_conn_alloc(void);
 void ksmbd_conn_free(struct ksmbd_conn *conn);
 bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c);
@@ -162,6 +163,8 @@ void ksmbd_conn_init_server_callbacks(struct ksmbd_conn_ops *ops);
 int ksmbd_conn_handler_loop(void *p);
 int ksmbd_conn_transport_init(void);
 void ksmbd_conn_transport_destroy(void);
+void ksmbd_conn_lock(struct ksmbd_conn *conn);
+void ksmbd_conn_unlock(struct ksmbd_conn *conn);
 
 /*
  * WARNING
@@ -169,43 +172,60 @@ void ksmbd_conn_transport_destroy(void);
  * This is a hack. We will move status to a proper place once we land
  * a multi-sessions support.
  */
-static inline bool ksmbd_conn_good(struct ksmbd_work *work)
+static inline bool ksmbd_conn_good(struct ksmbd_conn *conn)
 {
-	return work->conn->status == KSMBD_SESS_GOOD;
+	return READ_ONCE(conn->status) == KSMBD_SESS_GOOD;
 }
 
-static inline bool ksmbd_conn_need_negotiate(struct ksmbd_work *work)
+static inline bool ksmbd_conn_need_negotiate(struct ksmbd_conn *conn)
 {
-	return work->conn->status == KSMBD_SESS_NEED_NEGOTIATE;
+	return READ_ONCE(conn->status) == KSMBD_SESS_NEED_NEGOTIATE;
 }
 
-static inline bool ksmbd_conn_need_reconnect(struct ksmbd_work *work)
+static inline bool ksmbd_conn_need_reconnect(struct ksmbd_conn *conn)
 {
-	return work->conn->status == KSMBD_SESS_NEED_RECONNECT;
+	return READ_ONCE(conn->status) == KSMBD_SESS_NEED_RECONNECT;
 }
 
-static inline bool ksmbd_conn_exiting(struct ksmbd_work *work)
+static inline bool ksmbd_conn_exiting(struct ksmbd_conn *conn)
 {
-	return work->conn->status == KSMBD_SESS_EXITING;
+	return READ_ONCE(conn->status) == KSMBD_SESS_EXITING;
 }
 
-static inline void ksmbd_conn_set_good(struct ksmbd_work *work)
+static inline bool ksmbd_conn_releasing(struct ksmbd_conn *conn)
 {
-	work->conn->status = KSMBD_SESS_GOOD;
+	return READ_ONCE(conn->status) == KSMBD_SESS_RELEASING;
 }
 
-static inline void ksmbd_conn_set_need_negotiate(struct ksmbd_work *work)
+static inline void ksmbd_conn_set_new(struct ksmbd_conn *conn)
 {
-	work->conn->status = KSMBD_SESS_NEED_NEGOTIATE;
+	WRITE_ONCE(conn->status, KSMBD_SESS_NEW);
 }
 
-static inline void ksmbd_conn_set_need_reconnect(struct ksmbd_work *work)
+static inline void ksmbd_conn_set_good(struct ksmbd_conn *conn)
 {
-	work->conn->status = KSMBD_SESS_NEED_RECONNECT;
+	WRITE_ONCE(conn->status, KSMBD_SESS_GOOD);
 }
 
-static inline void ksmbd_conn_set_exiting(struct ksmbd_work *work)
+static inline void ksmbd_conn_set_need_negotiate(struct ksmbd_conn *conn)
 {
-	work->conn->status = KSMBD_SESS_EXITING;
+	WRITE_ONCE(conn->status, KSMBD_SESS_NEED_NEGOTIATE);
 }
+
+static inline void ksmbd_conn_set_need_reconnect(struct ksmbd_conn *conn)
+{
+	WRITE_ONCE(conn->status, KSMBD_SESS_NEED_RECONNECT);
+}
+
+static inline void ksmbd_conn_set_exiting(struct ksmbd_conn *conn)
+{
+	WRITE_ONCE(conn->status, KSMBD_SESS_EXITING);
+}
+
+static inline void ksmbd_conn_set_releasing(struct ksmbd_conn *conn)
+{
+	WRITE_ONCE(conn->status, KSMBD_SESS_RELEASING);
+}
+
+void ksmbd_all_conn_set_status(u64 sess_id, u32 status);
 #endif /* __CONNECTION_H__ */

fs/ksmbd/mgmt/tree_connect.c

@@ -109,7 +109,15 @@ int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
 struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess,
 						  unsigned int id)
 {
-	return xa_load(&sess->tree_conns, id);
+	struct ksmbd_tree_connect *tcon;
+
+	tcon = xa_load(&sess->tree_conns, id);
+	if (tcon) {
+		if (test_bit(TREE_CONN_EXPIRE, &tcon->status))
+			tcon = NULL;
+	}
+
+	return tcon;
 }
 
 struct ksmbd_share_config *ksmbd_tree_conn_share(struct ksmbd_session *sess,
@@ -129,6 +137,9 @@ int ksmbd_tree_conn_session_logoff(struct ksmbd_session *sess)
 	struct ksmbd_tree_connect *tc;
 	unsigned long id;
 
+	if (!sess)
+		return -EINVAL;
+
 	xa_for_each(&sess->tree_conns, id, tc)
 		ret |= ksmbd_tree_conn_disconnect(sess, tc);
 	xa_destroy(&sess->tree_conns);

fs/ksmbd/mgmt/tree_connect.h

@@ -14,6 +14,8 @@ struct ksmbd_share_config;
 struct ksmbd_user;
 struct ksmbd_conn;
 
+#define TREE_CONN_EXPIRE		1
+
 struct ksmbd_tree_connect {
 	int				id;
 
@@ -25,6 +27,7 @@ struct ksmbd_tree_connect {
 
 	int				maximal_access;
 	bool				posix_extensions;
+	unsigned long			status;
 };
 
 struct ksmbd_tree_conn_status {

fs/ksmbd/mgmt/user_session.c

@@ -144,10 +144,6 @@ void ksmbd_session_destroy(struct ksmbd_session *sess)
 	if (!sess)
 		return;
 
-	down_write(&sessions_table_lock);
-	hash_del(&sess->hlist);
-	up_write(&sessions_table_lock);
-
 	if (sess->user)
 		ksmbd_free_user(sess->user);
 
@@ -165,17 +161,39 @@ static struct ksmbd_session *__session_lookup(unsigned long long id)
 	struct ksmbd_session *sess;
 
 	hash_for_each_possible(sessions_table, sess, hlist, id) {
-		if (id == sess->id)
+		if (id == sess->id) {
+			sess->last_active = jiffies;
 			return sess;
 		}
+	}
 	return NULL;
 }
 
+static void ksmbd_expire_session(struct ksmbd_conn *conn)
+{
+	unsigned long id;
+	struct ksmbd_session *sess;
+
+	down_write(&sessions_table_lock);
+	xa_for_each(&conn->sessions, id, sess) {
+		if (sess->state != SMB2_SESSION_VALID ||
+		    time_after(jiffies,
+			       sess->last_active + SMB2_SESSION_TIMEOUT)) {
+			xa_erase(&conn->sessions, sess->id);
+			hash_del(&sess->hlist);
+			ksmbd_session_destroy(sess);
+			continue;
+		}
+	}
+	up_write(&sessions_table_lock);
+}
+
 int ksmbd_session_register(struct ksmbd_conn *conn,
 			   struct ksmbd_session *sess)
 {
 	sess->dialect = conn->dialect;
 	memcpy(sess->ClientGUID, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE);
+	ksmbd_expire_session(conn);
 	return xa_err(xa_store(&conn->sessions, sess->id, sess, GFP_KERNEL));
 }
 
@@ -188,47 +206,56 @@ static int ksmbd_chann_del(struct ksmbd_conn *conn, struct ksmbd_session *sess)
 		return -ENOENT;
 
 	kfree(chann);
-
 	return 0;
 }
 
 void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 {
 	struct ksmbd_session *sess;
+	unsigned long id;
 
+	down_write(&sessions_table_lock);
 	if (conn->binding) {
 		int bkt;
+		struct hlist_node *tmp;
 
-		down_write(&sessions_table_lock);
-		hash_for_each(sessions_table, bkt, sess, hlist) {
-			if (!ksmbd_chann_del(conn, sess)) {
-				up_write(&sessions_table_lock);
-				goto sess_destroy;
+		hash_for_each_safe(sessions_table, bkt, tmp, sess, hlist) {
+			if (!ksmbd_chann_del(conn, sess) &&
+			    xa_empty(&sess->ksmbd_chann_list)) {
+				hash_del(&sess->hlist);
+				ksmbd_session_destroy(sess);
+			}
 		}
 	}
-		up_write(&sessions_table_lock);
-	} else {
-		unsigned long id;
 
 	xa_for_each(&conn->sessions, id, sess) {
-			if (!ksmbd_chann_del(conn, sess))
-				goto sess_destroy;
-		}
-	}
+		unsigned long chann_id;
+		struct channel *chann;
 
-	return;
+		xa_for_each(&sess->ksmbd_chann_list, chann_id, chann) {
+			if (chann->conn != conn)
+				ksmbd_conn_set_exiting(chann->conn);
+		}
 
-sess_destroy:
+		ksmbd_chann_del(conn, sess);
 		if (xa_empty(&sess->ksmbd_chann_list)) {
 			xa_erase(&conn->sessions, sess->id);
+			hash_del(&sess->hlist);
 			ksmbd_session_destroy(sess);
 		}
+	}
+	up_write(&sessions_table_lock);
 }
 
 struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
 					   unsigned long long id)
 {
-	return xa_load(&conn->sessions, id);
+	struct ksmbd_session *sess;
+
+	sess = xa_load(&conn->sessions, id);
+	if (sess)
+		sess->last_active = jiffies;
+	return sess;
 }
 
 struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id)
@@ -237,6 +264,8 @@ struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id)
 
 	down_read(&sessions_table_lock);
 	sess = __session_lookup(id);
+	if (sess)
+		sess->last_active = jiffies;
 	up_read(&sessions_table_lock);
 
 	return sess;
@@ -315,6 +344,8 @@ static struct ksmbd_session *__session_create(int protocol)
 	if (ksmbd_init_file_table(&sess->file_table))
 		goto error;
 
+	sess->last_active = jiffies;
+	sess->state = SMB2_SESSION_IN_PROGRESS;
 	set_session_flag(sess, protocol);
 	xa_init(&sess->tree_conns);
 	xa_init(&sess->ksmbd_chann_list);

fs/ksmbd/mgmt/user_session.h

@@ -59,6 +59,7 @@ struct ksmbd_session {
 	__u8				smb3signingkey[SMB3_SIGN_KEY_SIZE];
 
 	struct ksmbd_file_table		file_table;
+	unsigned long			last_active;
 };
 
 static inline int test_session_flag(struct ksmbd_session *sess, int bit)

fs/ksmbd/server.c

@@ -93,7 +93,8 @@ static inline int check_conn_state(struct ksmbd_work *work)
 {
 	struct smb_hdr *rsp_hdr;
 
-	if (ksmbd_conn_exiting(work) || ksmbd_conn_need_reconnect(work)) {
+	if (ksmbd_conn_exiting(work->conn) ||
+	    ksmbd_conn_need_reconnect(work->conn)) {
 		rsp_hdr = work->response_buf;
 		rsp_hdr->Status.CifsError = STATUS_CONNECTION_DISCONNECTED;
 		return 1;
@@ -605,6 +606,7 @@ static int __init ksmbd_server_init(void)
 static void __exit ksmbd_server_exit(void)
 {
 	ksmbd_server_shutdown();
+	rcu_barrier();
 	ksmbd_release_inode_hash();
 }
 

fs/ksmbd/smb2pdu.c

@@ -248,7 +248,7 @@ int init_smb2_neg_rsp(struct ksmbd_work *work)
 
 	rsp = smb2_get_msg(work->response_buf);
 
-	WARN_ON(ksmbd_conn_good(work));
+	WARN_ON(ksmbd_conn_good(conn));
 
 	rsp->StructureSize = cpu_to_le16(65);
 	ksmbd_debug(SMB, "conn->dialect 0x%x\n", conn->dialect);
@@ -277,7 +277,7 @@ int init_smb2_neg_rsp(struct ksmbd_work *work)
 		rsp->SecurityMode |= SMB2_NEGOTIATE_SIGNING_REQUIRED_LE;
 	conn->use_spnego = true;
 
-	ksmbd_conn_set_need_negotiate(work);
+	ksmbd_conn_set_need_negotiate(conn);
 	return 0;
 }
 
@@ -561,7 +561,7 @@ int smb2_check_user_session(struct ksmbd_work *work)
 	    cmd == SMB2_SESSION_SETUP_HE)
 		return 0;
 
-	if (!ksmbd_conn_good(work))
+	if (!ksmbd_conn_good(conn))
 		return -EINVAL;
 
 	sess_id = le64_to_cpu(req_hdr->SessionId);
@@ -594,7 +594,7 @@ static void destroy_previous_session(struct ksmbd_conn *conn,
 
 	prev_sess->state = SMB2_SESSION_EXPIRED;
 	xa_for_each(&prev_sess->ksmbd_chann_list, index, chann)
-		chann->conn->status = KSMBD_SESS_EXITING;
+		ksmbd_conn_set_exiting(chann->conn);
 }
 
 /**
@@ -1051,7 +1051,7 @@ int smb2_handle_negotiate(struct ksmbd_work *work)
 
 	ksmbd_debug(SMB, "Received negotiate request\n");
 	conn->need_neg = false;
-	if (ksmbd_conn_good(work)) {
+	if (ksmbd_conn_good(conn)) {
 		pr_err("conn->tcp_status is already in CifsGood State\n");
 		work->send_no_response = 1;
 		return rc;
@@ -1205,7 +1205,7 @@ int smb2_handle_negotiate(struct ksmbd_work *work)
 	}
 
 	conn->srv_sec_mode = le16_to_cpu(rsp->SecurityMode);
-	ksmbd_conn_set_need_negotiate(work);
+	ksmbd_conn_set_need_negotiate(conn);
 
 err_out:
 	if (rc < 0)
@@ -1431,7 +1431,7 @@ static int ntlm_authenticate(struct ksmbd_work *work)
 		 * Reuse session if anonymous try to connect
 		 * on reauthetication.
 		 */
-		if (ksmbd_anonymous_user(user)) {
+		if (conn->binding == false && ksmbd_anonymous_user(user)) {
 			ksmbd_free_user(user);
 			return 0;
 		}
@@ -1445,7 +1445,7 @@ static int ntlm_authenticate(struct ksmbd_work *work)
 		sess->user = user;
 	}
 
-	if (user_guest(sess->user)) {
+	if (conn->binding == false && user_guest(sess->user)) {
 		rsp->SessionFlags = SMB2_SESSION_FLAG_IS_GUEST_LE;
 	} else {
 		struct authenticate_message *authblob;
@@ -1628,6 +1628,7 @@ int smb2_sess_setup(struct ksmbd_work *work)
 	rsp->SecurityBufferLength = 0;
 	inc_rfc1001_len(work->response_buf, 9);
 
+	ksmbd_conn_lock(conn);
 	if (!req->hdr.SessionId) {
 		sess = ksmbd_smb2_session_create();
 		if (!sess) {
@@ -1675,11 +1676,22 @@ int smb2_sess_setup(struct ksmbd_work *work)
 			goto out_err;
 		}
 
+		if (ksmbd_conn_need_reconnect(conn)) {
+			rc = -EFAULT;
+			sess = NULL;
+			goto out_err;
+		}
+
 		if (ksmbd_session_lookup(conn, sess_id)) {
 			rc = -EACCES;
 			goto out_err;
 		}
 
+		if (user_guest(sess->user)) {
+			rc = -EOPNOTSUPP;
+			goto out_err;
+		}
+
 		conn->binding = true;
 	} else if ((conn->dialect < SMB30_PROT_ID ||
 		    server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL) &&
@@ -1694,11 +1706,19 @@ int smb2_sess_setup(struct ksmbd_work *work)
 			rc = -ENOENT;
 			goto out_err;
 		}
+
+		if (sess->state == SMB2_SESSION_EXPIRED) {
+			rc = -EFAULT;
+			goto out_err;
 		}
-	work->sess = sess;
 
-	if (sess->state == SMB2_SESSION_EXPIRED)
-		sess->state = SMB2_SESSION_IN_PROGRESS;
+		if (ksmbd_conn_need_reconnect(conn)) {
+			rc = -EFAULT;
+			sess = NULL;
+			goto out_err;
+		}
+	}
+	work->sess = sess;
 
 	negblob_off = le16_to_cpu(req->SecurityBufferOffset);
 	negblob_len = le16_to_cpu(req->SecurityBufferLength);
@@ -1729,8 +1749,10 @@ int smb2_sess_setup(struct ksmbd_work *work)
 				goto out_err;
 			}
 
-			ksmbd_conn_set_good(work);
+			if (!ksmbd_conn_need_reconnect(conn)) {
+				ksmbd_conn_set_good(conn);
 				sess->state = SMB2_SESSION_VALID;
+			}
 			kfree(sess->Preauth_HashValue);
 			sess->Preauth_HashValue = NULL;
 		} else if (conn->preferred_auth_mech == KSMBD_AUTH_NTLMSSP) {
@@ -1752,8 +1774,10 @@ int smb2_sess_setup(struct ksmbd_work *work)
 				if (rc)
 					goto out_err;
 
-				ksmbd_conn_set_good(work);
+				if (!ksmbd_conn_need_reconnect(conn)) {
+					ksmbd_conn_set_good(conn);
 					sess->state = SMB2_SESSION_VALID;
+				}
 				if (conn->binding) {
 					struct preauth_session *preauth_sess;
 
@@ -1766,6 +1790,10 @@ int smb2_sess_setup(struct ksmbd_work *work)
 				}
 				kfree(sess->Preauth_HashValue);
 				sess->Preauth_HashValue = NULL;
+			} else {
+				pr_info_ratelimited("Unknown NTLMSSP message type : 0x%x\n",
+						le32_to_cpu(negblob->MessageType));
+				rc = -EINVAL;
 			}
 		} else {
 			/* TODO: need one more negotiation */
@@ -1788,6 +1816,8 @@ int smb2_sess_setup(struct ksmbd_work *work)
 		rsp->hdr.Status = STATUS_NETWORK_SESSION_EXPIRED;
 	else if (rc == -ENOMEM)
 		rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES;
+	else if (rc == -EOPNOTSUPP)
+		rsp->hdr.Status = STATUS_NOT_SUPPORTED;
 	else if (rc)
 		rsp->hdr.Status = STATUS_LOGON_FAILURE;
 
@@ -1815,14 +1845,17 @@ int smb2_sess_setup(struct ksmbd_work *work)
 			if (sess->user && sess->user->flags & KSMBD_USER_FLAG_DELAY_SESSION)
 				try_delay = true;
 
-			xa_erase(&conn->sessions, sess->id);
-			ksmbd_session_destroy(sess);
-			work->sess = NULL;
-			if (try_delay)
+			sess->last_active = jiffies;
+			sess->state = SMB2_SESSION_EXPIRED;
+			if (try_delay) {
+				ksmbd_conn_set_need_reconnect(conn);
 				ssleep(5);
+				ksmbd_conn_set_need_negotiate(conn);
+			}
 		}
 	}
 
+	ksmbd_conn_unlock(conn);
 	return rc;
 }
 
@@ -2020,11 +2053,12 @@ int smb2_tree_disconnect(struct ksmbd_work *work)
 
 	ksmbd_debug(SMB, "request\n");
 
-	if (!tcon) {
+	if (!tcon || test_and_set_bit(TREE_CONN_EXPIRE, &tcon->status)) {
 		struct smb2_tree_disconnect_req *req =
 			smb2_get_msg(work->request_buf);
 
 		ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId);
+
 		rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
 		smb2_set_err_rsp(work);
 		return 0;
@@ -2046,21 +2080,25 @@ int smb2_session_logoff(struct ksmbd_work *work)
 {
 	struct ksmbd_conn *conn = work->conn;
 	struct smb2_logoff_rsp *rsp = smb2_get_msg(work->response_buf);
-	struct ksmbd_session *sess = work->sess;
+	struct ksmbd_session *sess;
+	struct smb2_logoff_req *req = smb2_get_msg(work->request_buf);
+	u64 sess_id = le64_to_cpu(req->hdr.SessionId);
 
 	rsp->StructureSize = cpu_to_le16(4);
 	inc_rfc1001_len(work->response_buf, 4);
 
 	ksmbd_debug(SMB, "request\n");
 
-	/* setting CifsExiting here may race with start_tcp_sess */
-	ksmbd_conn_set_need_reconnect(work);
+	ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_RECONNECT);
 	ksmbd_close_session_fds(work);
-	ksmbd_conn_wait_idle(conn);
+	ksmbd_conn_wait_idle(conn, sess_id);
 
+	/*
+	 * Re-lookup session to validate if session is deleted
+	 * while waiting request complete
+	 */
+	sess = ksmbd_session_lookup_all(conn, sess_id);
 	if (ksmbd_tree_conn_session_logoff(sess)) {
-		struct smb2_logoff_req *req = smb2_get_msg(work->request_buf);
-
 		ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId);
 		rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
 		smb2_set_err_rsp(work);
@@ -2072,9 +2110,7 @@ int smb2_session_logoff(struct ksmbd_work *work)
 
 	ksmbd_free_user(sess->user);
 	sess->user = NULL;
-
-	/* let start_tcp_sess free connection info now */
-	ksmbd_conn_set_need_negotiate(work);
+	ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_NEGOTIATE);
 	return 0;
 }
 
@@ -4881,6 +4917,9 @@ static int smb2_get_info_filesystem(struct ksmbd_work *work,
 	int rc = 0, len;
 	int fs_infoclass_size = 0;
 
+	if (!share->path)
+		return -EIO;
+
 	rc = kern_path(share->path, LOOKUP_NO_SYMLINKS, &path);
 	if (rc) {
 		pr_err("cannot create vfs path\n");
@@ -6826,7 +6865,7 @@ int smb2_lock(struct ksmbd_work *work)
 
 		nolock = 1;
 		/* check locks in connection list */
-		read_lock(&conn_list_lock);
+		down_read(&conn_list_lock);
 		list_for_each_entry(conn, &conn_list, conns_list) {
 			spin_lock(&conn->llist_lock);
 			list_for_each_entry_safe(cmp_lock, tmp2, &conn->lock_list, clist) {
@@ -6843,7 +6882,7 @@ int smb2_lock(struct ksmbd_work *work)
 						list_del(&cmp_lock->flist);
 						list_del(&cmp_lock->clist);
 						spin_unlock(&conn->llist_lock);
-						read_unlock(&conn_list_lock);
+						up_read(&conn_list_lock);
 
 						locks_free_lock(cmp_lock->fl);
 						kfree(cmp_lock);
@@ -6865,7 +6904,7 @@ int smb2_lock(struct ksmbd_work *work)
 				    cmp_lock->start > smb_lock->start &&
 				    cmp_lock->start < smb_lock->end) {
 					spin_unlock(&conn->llist_lock);
-					read_unlock(&conn_list_lock);
+					up_read(&conn_list_lock);
 					pr_err("previous lock conflict with zero byte lock range\n");
 					goto out;
 				}
@@ -6874,7 +6913,7 @@ int smb2_lock(struct ksmbd_work *work)
 				    smb_lock->start > cmp_lock->start &&
 				    smb_lock->start < cmp_lock->end) {
 					spin_unlock(&conn->llist_lock);
-					read_unlock(&conn_list_lock);
+					up_read(&conn_list_lock);
 					pr_err("current lock conflict with zero byte lock range\n");
 					goto out;
 				}
@@ -6885,14 +6924,14 @@ int smb2_lock(struct ksmbd_work *work)
 				      cmp_lock->end >= smb_lock->end)) &&
 				    !cmp_lock->zero_len && !smb_lock->zero_len) {
 					spin_unlock(&conn->llist_lock);
-					read_unlock(&conn_list_lock);
+					up_read(&conn_list_lock);
 					pr_err("Not allow lock operation on exclusive lock range\n");
 					goto out;
 				}
 			}
 			spin_unlock(&conn->llist_lock);
 		}
-		read_unlock(&conn_list_lock);
+		up_read(&conn_list_lock);
 out_check_cl:
 		if (smb_lock->fl->fl_type == F_UNLCK && nolock) {
 			pr_err("Try to unlock nolocked range\n");

fs/ksmbd/smb2pdu.h

@@ -61,6 +61,8 @@ struct preauth_integrity_info {
 #define SMB2_SESSION_IN_PROGRESS	BIT(0)
 #define SMB2_SESSION_VALID		BIT(1)
 
+#define SMB2_SESSION_TIMEOUT		(10 * HZ)
+
 struct create_durable_req_v2 {
 	struct create_context ccontext;
 	__u8   Name[8];

fs/ksmbd/transport_tcp.c

@@ -333,7 +333,7 @@ static int ksmbd_tcp_readv(struct tcp_transport *t, struct kvec *iov_orig,
 		if (length == -EINTR) {
 			total_read = -ESHUTDOWN;
 			break;
-		} else if (conn->status == KSMBD_SESS_NEED_RECONNECT) {
+		} else if (ksmbd_conn_need_reconnect(conn)) {
 			total_read = -EAGAIN;
 			break;
 		} else if (length == -ERESTARTSYS || length == -EAGAIN) {