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IIRC, NTFS doesn't support permissions.

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config NTFS3_FS_POSIX_ACL

bool "NTFS POSIX Access Control Lists"

depends on NTFS3_FS

select FS_POSIX_ACL

help

POSIX Access Control Lists (ACLs) support additional access rights for users and groups beyond the standard owner/group/world scheme, and this option selects support for ACLs specifically for ntfs filesystems.

NOTE: this is linux only feature. Windows will ignore these ACLs.

I'm not sure, but iirc POSIX ACL and typical Unix permission (ala chmod 0755) are two different things.

Unix permissions are those you change via chmod while POSIX ACLs are those you view/change with getfacl/setfacl.

NTFS probably has that because Windows used to have (still has? dunno) a full POSIX subsystem / compatibility layer.

NTFS actually does support permissions, it's Windows that doesn't. NTFS also supports symbolic links and hard links.

Not contradicting just genuinely wondering, what do you mean by windows doesn't? I have different permissions setup for various users on different folders on ntfs volumes in regular windows 10 installs. Or do you mean another sort of permissions?

In this context they are talking about the POSIX permissions related to running Linux on the drive which NTFS supports but Windows does not use. Instead Windows uses another attribute for their security descriptor model which is also used by other non-file objects throughout the OS.

A lot of this stuff is actually legacy from when NT hosted POSIX and Windows subsystems simultaneously on the same kernel.

Sadly that stuff is long since dead but they have in part revived some of the ideas with their SQL Server for Linux port and WSL of course.

Not sure why I'm getting downvoted here. When POSIX subsystem of the NT kernel they added support for many POSIX style features. Namely POSIX ACL support, hard links and case-sensitivity.

I guess the reality of this is lost to history and folks like me that remember NT for what it was before it was relegated to just hosting Win32.

Does it support suid?

Um, I've had plenty of times I got a UAC (~windows sudo) prompt trying to access files I didn't have permissions to.

Doesn't WSL support Linux permissions via EAs? Couldn't they use the same model?

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