ksmbd: update tree disconnect race update 2

Signed-off-by: Namjae Jeon <[email protected]>
namjaejeon · Oct 3, 2023 · 97a934a · 97a934a
1 parent 11d3bf6
commit 97a934a
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Showing 2 changed files with 24 additions and 9 deletions.
diff --git a/mgmt/tree_connect.c b/mgmt/tree_connect.c
@@ -109,12 +109,6 @@ int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
 	int ret;
 
 	write_lock(&sess->tree_conns_lock);
-	if (tree_conn->t_state == TREE_DISCONNECTED) {
-		write_unlock(&sess->tree_conns_lock);
-		return -ENOENT;
-	}
-
-	tree_conn->t_state = TREE_DISCONNECTED;
 	xa_erase(&sess->tree_conns, tree_conn->id);
 	write_unlock(&sess->tree_conns_lock);
 
@@ -156,8 +150,18 @@ 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/smb2pdu.c b/smb2pdu.c
@@ -2146,13 +2146,24 @@ int smb2_tree_disconnect(struct ksmbd_work *work)
 		ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId);
 
 		rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
-		smb2_set_err_rsp(work);
 		err = -ENOENT;
 		goto err_out;
 	}
 
 	ksmbd_close_tree_conn_fds(work);
-	atomic_dec(&tcon->refcount);
+
+	write_lock(&sess->tree_conns_lock);
+	if (tcon->t_state == TREE_DISCONNECTED) {
+		write_unlock(&sess->tree_conns_lock);
+		rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
+		err = -ENOENT;
+		goto err_out;
+	}
+
+	BUG_ON(atomic_dec_and_test(&tcon->refcount));
+	tcon->t_state = TREE_DISCONNECTED;
+	write_unlock(&sess->tree_conns_lock);
+
 	err = ksmbd_tree_conn_disconnect(sess, tcon);
 	if (err) {
 		rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;