os: MkdirAll does not return an error when insufficient access privilege exists on a path component

[hashibuto]

What version of Go are you using (go version)?

$ go version
go version go1.16 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GOOS="linux"
GOARCH="amd64"

What did you do?

Attempt to create a directory with insufficient permissions in /root using os.MkdirAll
Example:

os.MkdirAll("/root/mydir", os.FileMode(0700)

What did you expect to see?

I expected an error to be returned, indicating a permission issue.

What did you see instead?

A nil was returned for the error, but obviously the directory was not created.

[gopherbot]

Change https://golang.org/cl/299611 mentions this issue: os: return an error in os.MkdirAll when user permissions are insufficient