The long road to a fix for CVE-2021-20316

Posted Feb 15, 2022 19:45 UTC (Tue) by Wol (subscriber, #4433)
In reply to: The long road to a fix for CVE-2021-20316 by nybble41
Parent article: The long road to a fix for CVE-2021-20316

> Which OS do you use that doesn't have symlinks?

DID I use ... they pre-date linux, MacOS and Windows ...

A Multics-derivative called Pr1mos, various DOSes (I don't think I used CP/M ...) (and I don't mean MS-DOS and derivatives ...)

There used to be a world with many different OSes, not just the three behemoths we have now.

Cheers,
Wol

The long road to a fix for CVE-2021-20316

Posted Feb 16, 2022 15:06 UTC (Wed) by foom (subscriber, #14868) [Link] (2 responses)

Classic macos didn't have symlinks either. It did have "aliases", but those were (and are -- they still exist in modern macos, alongside symlinks and hardlinks and copy-on-write copies..) more akin to windows lnk files, as they're resolved at a higher level than basic filesystem traversal.

This allows them to be less fragile -- they store multiple ways of finding the original file, so it can still be used even in case the target has been moved or renamed. They can also do things like display a gui prompt to ask the user to insert the appropriate floppy disk which contains the target file, or automatically mount the proper remote volume.

However, the downside is that they are not functional for command-line/cross platform programs, which don't use alias-aware file access apis.

The long road to a fix for CVE-2021-20316

Posted Feb 17, 2022 12:52 UTC (Thu) by khim (subscriber, #9252) [Link] (1 responses)

> However, the downside is that they are not functional for command-line/cross platform programs, which don't use alias-aware file access apis.

But classic MacOS had no support for command-line apps which solved that problem.

The long road to a fix for CVE-2021-20316

Posted Feb 19, 2022 21:56 UTC (Sat) by foom (subscriber, #14868) [Link]

Classic macos did, kinda, have a shell, shell scripts, and command line apps, in MPW (https://en.m.wikipedia.org/wiki/Macintosh_Programmer's_Workshop). But that was just an app, not the fundamental underpinnings of the system.

(Of course modern macos does have both command line POSIX apps and aliases)