有时候在编辑/etc/sudoers文件时，不小心编辑错误并保存，导致用户没有sudo权限，无法使用sudu
此时可以重启系统，选择进入“修复模式”
开始进行具体的操作
sudo cp /etc/sudoers /etc/sudoers.backup
sudo nano /etc/sudoers
确保你新的sudoers文件的内容如下
# /etc/sudoers
#
# This file MUST be edited with the 'visudo' command as root.
#
# See the man page for details on how to write a sudoers file.
#
Defaults env_reset
# Host alias specification
# User alias specification
# Cmnd alias specification
# User privilege specification
root ALL=(ALL) ALL
# Allow members of group sudo to execute any command after they have
# provided their password
# (Note that later entries override this, so you might need to move
# it further down)
%sudo ALL=(ALL) ALL
#
#includedir /etc/sudoers.d
# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL
#
# This file MUST be edited with the 'visudo' command as root.
#
# See the man page for details on how to write a sudoers file.
#
Defaults env_reset
# Host alias specification
# User alias specification
# Cmnd alias specification
# User privilege specification
root ALL=(ALL) ALL
# Allow members of group sudo to execute any command after they have
# provided their password
# (Note that later entries override this, so you might need to move
# it further down)
%sudo ALL=(ALL) ALL
#
#includedir /etc/sudoers.d
# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL
如果没有编辑权限时，先给sudoers文件增加写权限，然后完成编辑，最后去掉写入权限。重启系统即可