Hello, I'd like to start a discussion regarding setting HOME_MODE by default in the /etc/login.defs file (owned by sys-apps/shadow package).
Upstream keeps HOME_MODE commented: https://github.com/shadow-maint/shadow/blob/3e59e9613ec40c51c19c7bb5c28468e33a4529d5/etc/login.defs#L207 HOME_MODE affects only useradd and newuser commands: if HOME_MODE is set, they will use the specified permission when creating a user home directory, otherwise the default UMASK will be used. Since the default umask is 022, keeping HOME_MODE unset will result in home readable home directories created by useradd, which goes against security best practices. The proposal is to set HOME_MODE to 0700, or at least 0750: RedHat and RH based distros, OpenSuse, ArchLinux all set it to 0700, Ubuntu has it at 0750. Debian and Gentoo are two exceptions, keeping the upstream value of HOME_MODE (although login.defs is changed in other ways). I previously made a PR on github where you can find more details ( https://github.com/gentoo/gentoo/pull/35231), but as pointed in the comments this probably warrants some discussion beforehand. I can understand the argument against the change, which is keeping in sync with upstream and don't risk changing the historic default behaviour of tools some users might rely upon. I do believe though there's merit in providing safer and secure defaults, so I would like HOME_MODE to have a safe default value for Gentoo and Gentoo based distros. Have a nice day, Daniel
