这是 Ubuntu 20.4 或 Ubuntu 22.04 的全新安装，但当我尝试从 Ubuntu 控制台启用 ufw 时，它们都失败了，并出现如下错误。
sudo ufw enable
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/ufw/util.py", line 427, in under_ssh
ppid = get_ppid(pid)
File "/usr/lib/python3/dist-packages/ufw/util.py", line 419, in get_ppid
ppid = open(name).readlines()[0].split(')')[1].split()[1]
IndexError: list index out of range
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/sbin/ufw", line 138, in <module>
not ui.continue_under_ssh():
File "/usr/lib/python3/dist-packages/ufw/frontend.py", line 901, in continue_under_ssh
if self.backend.do_checks and ufw.util.under_ssh(): # pragma: no cover
File …