CVE-2026-78422 zbus_polkit: polkit authorization bypass via PID reuse due to incorrect D-Bus type for the subject UID

Subject::newforowner in the zbuspolkit crate encodes the uid entry of a unix-process polkit subject as an unsigned 32-bit integer D-Bus type u, whereas the org.freedesktop.PolicyKit1.Authority interface specifies a signed 32-bit integer D-Bus type i. Because of this type mismatch, polkit silently...