fix issue #1853

lib/commands.py

@@ -94,6 +94,8 @@ class Commands:
         cmd = known_commands[method]
         if cmd.requires_password and self.wallet.use_encryption:
             self._password = apply(password_getter,())
+            if self._password is None:
+                return
         f = getattr(self, method)
         result = f(*args)
         self._password = None

lib/wallet.py

@@ -1107,6 +1107,8 @@ class Abstract_Wallet(PrintError):
             tx.sign(keypairs)
 
     def update_password(self, old_password, new_password):
+        self.check_password(old_password)
+
         if new_password == '':
             new_password = None