protonscr

Steam SHOULD NOT demand user-namespace

steamclosed
ValveSoftware/steam-for-linux#11237 · opened 2024-09-03 by sipaktli · updated 2024-09-04 · 2 comments · github
Ssipaktli 2024-09-03 github

Suddenly you have decided to demand unprivileged user namespaces.
This leaves the system open to a myriad, enormous number of vulnerabilities that could not be exploited without it.
What is the justification for demanding this anyway?

I have zero hope of course on changing anybody's mind or make you revert. Because this decision is either intentionally malicious or profoundly ignorant. Whoever took this decision needs to be slapped.

https://security.stackexchange.com/questions/209529/what-does-enabling-kernel-unprivileged-userns-clone-do

Since you won't change your mind, I will no longer play steam. Ever again. No purchasing new games, nothing. It's a shame but I guess it is the universe telling me quit gaming... or you telling me to fk off!

Kkisak-valve maintainer 2024-09-03 github

Hello @sipaktli, Steam's web component is run inside of the Steam Linux Runtime 3.0 (sniper) container environment, and this container is setup by Pressure Vessel.

Pressure Vessel is a cousin of Flatpak and similarly uses bubblewrap. Noted at https://github.com/ValveSoftware/steam-runtime/blob/master/doc/steamlinuxruntime-known-issues.md#kernelunprivileged_userns_clone and discussed in https://github.com/ValveSoftware/steam-runtime/issues/297, if your system provides a setuid-root variant of bwrap, Steam will use that as an alternative to needing user namespaces to function.

Ssipaktli 2024-09-04 github

Hi kisak!

Thanks for the reply.

Many distros don't use flatpak. Like Arch (used in steam deck). Many of us reject such things precisely because of security concerns. We could get into the old debate on why flatpak/snap is an incorrect technical approach (aka 'evil')... but I just want to be able to play games without annihilating the security of my system.

The justification in the link you have provided is "modern systems use flatpak so it must be cool". That is not a valid technical rationale.

  1. The runtime has been running fine thus far without requirement for unprivileged namespaces, so I still fail to see why it is randomly necessary now.
  2. Now, that's the runtime, but why should the native client require UNs???

There could not be any other more dangerous configuration to enable in a system than UNs. Is the security of systems not important at all? To me, the safety of my system is worth more than all gaming.