git config file permission lost after `git remote set-url origin https://`

Question

I was using capistrano for the deployment cap production deploy, the error message from capistrano

 DEBUG [3730481e]       fatal: unable to access './config': Permission denied

I found it's because the file permission lost.

the repo/config file permission 0664 before

-rw-rw-r--  1 ec ec 217 Mar  1 12:08 config

after git remote set-url origin https://myawesometoken:@github.com/myawesomeusername/myawesomeproject.git

the repo/config file permission was lost, 0000

----------  1 ec ec 217 Mar  1 12:09 config

[core]
        repositoryformatversion = 0
        filemode = true
        bare = true
[remote "origin"]
        url = https://myawesometoken:@github.com/myawesomeusername/myawesomeproject.git
        fetch = +refs/*:refs/*
        mirror = true