Running bash on windows 10, the simple syntax below works when I SSH to my webserver, but not when I exit out and am on my local machine. It doesn't give me an error, but I can see permissions are unchanged. I have to checked that I am set up as an administrator on my computer. Is this an error or is this just a consequence of the local operating system being windows? IF the later, it makes me question the value of using bash on windows if common operations such as this won't work.
$chmod 644 filename
Amade's answer is correct, but please note, the cmd only take effect in session scope. If you exit current bash, you'll lose your setting.
To fix this, you need to edit /etc/wsl.conf. and put below config in.
[automount]
enabled = true
options = "metadata"
Ref:
There was an update to WSL recently (source), which lets you change permissions to files (Insider Build 17063).
All you have to do is to run:
sudo umount /mnt/c
sudo mount -t drvfs C: /mnt/c -o metadata
来源：https://stackoverflow.com/questions/46610256/chmod-wsl-bash-doesnt-work