What is rootless bring brought up so much? It’s a container, it’s isolated from the host anyway, what does it matter what user runs inside? And if something breaks into the container they can trash the app in it and the shared volumes anyway, even if they’re not root.
Defense in depth. If something escapes the container it’s limited to only what’s under that user and not the whole system. Having access to the whole system makes it easier for malware to hide/persist itself.
Way too dependent on the setup, a container with absolutely no outside access theoretically just has the kernel, but usually we want to communicate with our docker images not just run them
Because a container is only as isolated from the host as you want it to be.
Suppose you run a container and mount the entire filesystem into it. If that container is running as root, it can then read and write anything it likes (including password databases and /etc/sudo)
So what? If I mount / in the container and choose to run it as root that’s my business. Why would the containerization engine second-guess what I’m doing?
How would you like it if sudo told you “I can’t let you be root, you could read and write anything you like, including password databases and /etc/sudo”?
Nothing to stop running podman containers with full root access by creating & running them as root, you run them as whatever user you want. I’ve done it to troubleshoot containers on more than one occasion, usually when I want to play with VPN or privileged ports but too lazy to do it proper. The end goal for a lot of ppl, including myself, is to run as many things as non-root as possible. Why? Best practices around security have you give a service the minimal access & resources it needs to do it’s tasks. Some people allow traffic from the internet to their containers & they probably feel a little bit safer running those programs as non-root since it can create an extra layer that may need to be broken to fully compromise a system.
The point is to minimize privilege to the least possible - not to make it impossible to create higher privileged containers. If a container doesn’t need to get direct raw hardware access, manage low ports on the host network, etc. then why should I give it root and let it be able to do those things? Mapping it to a user, controlling what resources it has access to, and restricting it’s capabilities means that in the event that my container gets compromised, my entire host isn’t necessarily screwed.
We’re not saying “sudo shouldn’t be able to run as root” but that “by default things shouldn’t be run with sudo - and you need a compelling reason to swap over when you do”
What is rootless bring brought up so much? It’s a container, it’s isolated from the host anyway, what does it matter what user runs inside? And if something breaks into the container they can trash the app in it and the shared volumes anyway, even if they’re not root.
Defense in depth. If something escapes the container it’s limited to only what’s under that user and not the whole system. Having access to the whole system makes it easier for malware to hide/persist itself.
Correct me if I’m wrong but containerization is enforced by the kernel, correct? If something escapes you’re pretty much screwed anyway.
There are many layers involved in preventing escapes from containers.
Way too dependent on the setup, a container with absolutely no outside access theoretically just has the kernel, but usually we want to communicate with our docker images not just run them
Because a container is only as isolated from the host as you want it to be.
Suppose you run a container and mount the entire filesystem into it. If that container is running as root, it can then read and write anything it likes (including password databases and /etc/sudo)
So what? If I mount / in the container and choose to run it as root that’s my business. Why would the containerization engine second-guess what I’m doing?
How would you like it if sudo told you “I can’t let you be root, you could read and write anything you like, including password databases and /etc/sudo”?
Nothing to stop running podman containers with full root access by creating & running them as root, you run them as whatever user you want. I’ve done it to troubleshoot containers on more than one occasion, usually when I want to play with VPN or privileged ports but too lazy to do it proper. The end goal for a lot of ppl, including myself, is to run as many things as non-root as possible. Why? Best practices around security have you give a service the minimal access & resources it needs to do it’s tasks. Some people allow traffic from the internet to their containers & they probably feel a little bit safer running those programs as non-root since it can create an extra layer that may need to be broken to fully compromise a system.
The point is to minimize privilege to the least possible - not to make it impossible to create higher privileged containers. If a container doesn’t need to get direct raw hardware access, manage low ports on the host network, etc. then why should I give it root and let it be able to do those things? Mapping it to a user, controlling what resources it has access to, and restricting it’s capabilities means that in the event that my container gets compromised, my entire host isn’t necessarily screwed.
We’re not saying “sudo shouldn’t be able to run as root” but that “by default things shouldn’t be run with sudo - and you need a compelling reason to swap over when you do”