Set USER and LOGNAME environment variables when dropping privileges #465
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When a service is configured to run as a non-root user (@user), finit correctly drops privileges via setuid() and sets HOME and PATH, but does not set the USER and LOGNAME environment variables. They remain set to "root" from boot time. This causes problems for software that determines its identity from the environment rather than getuid(). For example, rootless Podman checks os.Getenv("USER") first when looking up subordinate UID/GID ranges in /etc/subuid and /etc/subgid. With USER=root but UID=1000, Podman looks up root's subuid entry instead of the actual user's, causing applications like newuidmap to fail. Setting USER and LOGNAME to match the actual user identity follows POSIX conventions and matches the behavior of su, sudo, and login.
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When a service is configured to run as a non-root user (
@user), finit correctly drops privileges via setuid() and sets HOME and PATH, but does not set the USER and LOGNAME environment variables. They remain set to "root" from boot time.This causes problems for software that determines its identity from the environment rather than getuid(). For example, rootless Podman checks os.Getenv("USER") first when looking up subordinate UID/GID ranges in /etc/subuid and /etc/subgid.
With USER=root but UID=1000, Podman looks up root's subuid entry instead of the actual user's, causing applications like newuidmap to fail. Setting USER and LOGNAME to match the actual user identity follows POSIX conventions and matches the behavior of su, sudo, and login.
https://github.com/containers/podman/blob/fd90d334a3a7a66fd4e07b3fe98a18378bbc55ed/pkg/rootless/rootless_linux.go#L168