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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

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Systemd wants to expand to include a sudo replacement (outpost.fosspost.org)

submitted 7 months ago by [email protected] to c/[email protected]

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[–] [email protected] 43 points 7 months ago (1 children)

There's a rewrite of sudo happening in rust, but he wants to throw out the SUID idea altogether?

when invoked under the “run0” name (via a symlink) it behaves a lot like a sudo clone. But with one key difference: it’s not in fact SUID. Instead it just asks the service manager to invoke a command or shell under the target user’s UID. It allocates a new PTY for that, and then shovels data back and forth from the originating TTY and this PTY.

That sounds like opening up the door to what windows is doing UAC and the wonderful vulnerability that the GOG Launcher had for privilege escalation.

I'm not a security researcher, but giving arbitrary users the ability to tel PID 1 to run a binary of the user's choosing is... probably not what Pottering is suggesting, but opens up to such vulnerabilities. And if it's written in C/C++ my trust is further reduced.

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[–] [email protected] 6 points 7 months ago

Giving users access to PID1 running binaries, giving users access to the kernel running binaries as root, I don't see much difference. SUID was notorious in the past for being leaky, it only ended when distros got serious about fencing use of it in, giving it only to programs actually needing it, making sure that they drop privilege properly, etc.

If anything I'm in the PID1 camp because it's more microkernely. But in any case broader userspace shouldn't really care about the mechanism, only have an API to do it and that API being a bit in the file permissions is soooo 1960s.