1 files changed, 123 insertions, 22 deletions

diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c
index 8a5dcab05614..1c181ef99929 100644
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -18,7 +18,7 @@
 
 static DEFINE_IDA(session_ida);
 
-#define SESSION_HASH_BITS		3
+#define SESSION_HASH_BITS		12
 static DEFINE_HASHTABLE(sessions_table, SESSION_HASH_BITS);
 static DECLARE_RWSEM(sessions_table_lock);
 
@@ -59,10 +59,12 @@ static void ksmbd_session_rpc_clear_list(struct ksmbd_session *sess)
 	struct ksmbd_session_rpc *entry;
 	long index;
 
+	down_write(&sess->rpc_lock);
 	xa_for_each(&sess->rpc_handle_list, index, entry) {
 		xa_erase(&sess->rpc_handle_list, index);
 		__session_rpc_close(sess, entry);
 	}
+	up_write(&sess->rpc_lock);
 
 	xa_destroy(&sess->rpc_handle_list);
 }
@@ -90,32 +92,41 @@ static int __rpc_method(char *rpc_name)
 
 int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name)
 {
-	struct ksmbd_session_rpc *entry;
+	struct ksmbd_session_rpc *entry, *old;
 	struct ksmbd_rpc_command *resp;
-	int method;
+	int method, id;
 
 	method = __rpc_method(rpc_name);
 	if (!method)
 		return -EINVAL;
 
-	entry = kzalloc(sizeof(struct ksmbd_session_rpc), GFP_KERNEL);
+	entry = kzalloc(sizeof(struct ksmbd_session_rpc), KSMBD_DEFAULT_GFP);
 	if (!entry)
 		return -ENOMEM;
 
 	entry->method = method;
-	entry->id = ksmbd_ipc_id_alloc();
-	if (entry->id < 0)
+	entry->id = id = ksmbd_ipc_id_alloc();
+	if (id < 0)
 		goto free_entry;
-	xa_store(&sess->rpc_handle_list, entry->id, entry, GFP_KERNEL);
 
-	resp = ksmbd_rpc_open(sess, entry->id);
-	if (!resp)
+	down_write(&sess->rpc_lock);
+	old = xa_store(&sess->rpc_handle_list, id, entry, KSMBD_DEFAULT_GFP);
+	if (xa_is_err(old)) {
+		up_write(&sess->rpc_lock);
+		goto free_id;
+	}
+
+	resp = ksmbd_rpc_open(sess, id);
+	if (!resp) {
+		xa_erase(&sess->rpc_handle_list, entry->id);
+		up_write(&sess->rpc_lock);
 		goto free_id;
+	}
 
+	up_write(&sess->rpc_lock);
 	kvfree(resp);
-	return entry->id;
+	return id;
 free_id:
-	xa_erase(&sess->rpc_handle_list, entry->id);
 	ksmbd_rpc_id_free(entry->id);
 free_entry:
 	kfree(entry);
@@ -126,16 +137,20 @@ void ksmbd_session_rpc_close(struct ksmbd_session *sess, int id)
 {
 	struct ksmbd_session_rpc *entry;
 
+	down_write(&sess->rpc_lock);
 	entry = xa_erase(&sess->rpc_handle_list, id);
 	if (entry)
 		__session_rpc_close(sess, entry);
+	up_write(&sess->rpc_lock);
 }
 
 int ksmbd_session_rpc_method(struct ksmbd_session *sess, int id)
 {
 	struct ksmbd_session_rpc *entry;
 
+	lockdep_assert_held(&sess->rpc_lock);
 	entry = xa_load(&sess->rpc_handle_list, id);
+
 	return entry ? entry->method : 0;
 }
 
@@ -149,6 +164,7 @@ void ksmbd_session_destroy(struct ksmbd_session *sess)
 
 	ksmbd_tree_conn_session_logoff(sess);
 	ksmbd_destroy_file_table(&sess->file_table);
+	ksmbd_launch_ksmbd_durable_scavenger();
 	ksmbd_session_rpc_clear_list(sess);
 	free_channel_list(sess);
 	kfree(sess->Preauth_HashValue);
@@ -156,7 +172,7 @@ void ksmbd_session_destroy(struct ksmbd_session *sess)
 	kfree(sess);
 }
 
-static struct ksmbd_session *__session_lookup(unsigned long long id)
+struct ksmbd_session *__session_lookup(unsigned long long id)
 {
 	struct ksmbd_session *sess;
 
@@ -175,16 +191,19 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn)
 	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,
-			       sess->last_active + SMB2_SESSION_TIMEOUT)) {
+		if (atomic_read(&sess->refcnt) <= 1 &&
+		    (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(&conn->session_lock);
 	up_write(&sessions_table_lock);
 }
 
@@ -194,7 +213,7 @@ int ksmbd_session_register(struct ksmbd_conn *conn,
 	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));
+	return xa_err(xa_store(&conn->sessions, sess->id, sess, KSMBD_DEFAULT_GFP));
 }
 
 static int ksmbd_chann_del(struct ksmbd_conn *conn, struct ksmbd_session *sess)
@@ -223,11 +242,16 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 			if (!ksmbd_chann_del(conn, sess) &&
 			    xa_empty(&sess->ksmbd_chann_list)) {
 				hash_del(&sess->hlist);
-				ksmbd_session_destroy(sess);
+				down_write(&conn->session_lock);
+				xa_erase(&conn->sessions, sess->id);
+				up_write(&conn->session_lock);
+				if (atomic_dec_and_test(&sess->refcnt))
+					ksmbd_session_destroy(sess);
 			}
 		}
 	}
 
+	down_write(&conn->session_lock);
 	xa_for_each(&conn->sessions, id, sess) {
 		unsigned long chann_id;
 		struct channel *chann;
@@ -241,20 +265,42 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
 		if (xa_empty(&sess->ksmbd_chann_list)) {
 			xa_erase(&conn->sessions, sess->id);
 			hash_del(&sess->hlist);
-			ksmbd_session_destroy(sess);
+			if (atomic_dec_and_test(&sess->refcnt))
+				ksmbd_session_destroy(sess);
 		}
 	}
+	up_write(&conn->session_lock);
 	up_write(&sessions_table_lock);
 }
 
+bool is_ksmbd_session_in_connection(struct ksmbd_conn *conn,
+				   unsigned long long id)
+{
+	struct ksmbd_session *sess;
+
+	down_read(&conn->session_lock);
+	sess = xa_load(&conn->sessions, id);
+	if (sess) {
+		up_read(&conn->session_lock);
+		return true;
+	}
+	up_read(&conn->session_lock);
+
+	return false;
+}
+
 struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
 					   unsigned long long id)
 {
 	struct ksmbd_session *sess;
 
+	down_read(&conn->session_lock);
 	sess = xa_load(&conn->sessions, id);
-	if (sess)
+	if (sess) {
 		sess->last_active = jiffies;
+		ksmbd_user_session_get(sess);
+	}
+	up_read(&conn->session_lock);
 	return sess;
 }
 
@@ -265,7 +311,7 @@ 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;
+		ksmbd_user_session_get(sess);
 	up_read(&sessions_table_lock);
 
 	return sess;
@@ -284,12 +330,28 @@ struct ksmbd_session *ksmbd_session_lookup_all(struct ksmbd_conn *conn,
 	return sess;
 }
 
+void ksmbd_user_session_get(struct ksmbd_session *sess)
+{
+	atomic_inc(&sess->refcnt);
+}
+
+void ksmbd_user_session_put(struct ksmbd_session *sess)
+{
+	if (!sess)
+		return;
+
+	if (atomic_read(&sess->refcnt) <= 0)
+		WARN_ON(1);
+	else if (atomic_dec_and_test(&sess->refcnt))
+		ksmbd_session_destroy(sess);
+}
+
 struct preauth_session *ksmbd_preauth_session_alloc(struct ksmbd_conn *conn,
 						    u64 sess_id)
 {
 	struct preauth_session *sess;
 
-	sess = kmalloc(sizeof(struct preauth_session), GFP_KERNEL);
+	sess = kmalloc(sizeof(struct preauth_session), KSMBD_DEFAULT_GFP);
 	if (!sess)
 		return NULL;
 
@@ -301,6 +363,42 @@ struct preauth_session *ksmbd_preauth_session_alloc(struct ksmbd_conn *conn,
 	return sess;
 }
 
+void destroy_previous_session(struct ksmbd_conn *conn,
+			      struct ksmbd_user *user, u64 id)
+{
+	struct ksmbd_session *prev_sess;
+	struct ksmbd_user *prev_user;
+	int err;
+
+	down_write(&sessions_table_lock);
+	down_write(&conn->session_lock);
+	prev_sess = __session_lookup(id);
+	if (!prev_sess || prev_sess->state == SMB2_SESSION_EXPIRED)
+		goto out;
+
+	prev_user = prev_sess->user;
+	if (!prev_user ||
+	    strcmp(user->name, prev_user->name) ||
+	    user->passkey_sz != prev_user->passkey_sz ||
+	    memcmp(user->passkey, prev_user->passkey, user->passkey_sz))
+		goto out;
+
+	ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_RECONNECT);
+	err = ksmbd_conn_wait_idle_sess_id(conn, id);
+	if (err) {
+		ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP);
+		goto out;
+	}
+
+	ksmbd_destroy_file_table(&prev_sess->file_table);
+	prev_sess->state = SMB2_SESSION_EXPIRED;
+	ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP);
+	ksmbd_launch_ksmbd_durable_scavenger();
+out:
+	up_write(&conn->session_lock);
+	up_write(&sessions_table_lock);
+}
+
 static bool ksmbd_preauth_session_id_match(struct preauth_session *sess,
 					   unsigned long long id)
 {
@@ -337,7 +435,7 @@ static struct ksmbd_session *__session_create(int protocol)
 	if (protocol != CIFDS_SESSION_FLAG_SMB2)
 		return NULL;
 
-	sess = kzalloc(sizeof(struct ksmbd_session), GFP_KERNEL);
+	sess = kzalloc(sizeof(struct ksmbd_session), KSMBD_DEFAULT_GFP);
 	if (!sess)
 		return NULL;
 
@@ -351,6 +449,9 @@ 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);
+	atomic_set(&sess->refcnt, 2);
+	init_rwsem(&sess->rpc_lock);
 
 	ret = __init_smb2_session(sess);
 	if (ret)