我在CentOS上也遇到了这个问题. 事实证明，安装在CentO中的默认git已经过时了.

I also had this problem on CentOS. It turns out that the default git installed in CentOs is too out-of-dated.

请按照以下答案链接，尝试将git升级到CentOS上的最新版本，然后再次运行flutter doctor

Please try upgrading git to the latest version on CentOS by following this answer link and then run flutter doctor again