airootfs/etc/pam.d/su

   1 #%PAM-1.0
   2 auth            sufficient      pam_rootok.so
   3 auth            sufficient      pam_wheel.so trust use_uid
   4 auth            required        pam_unix.so
   5 account         required        pam_unix.so
   6 session         required        pam_unix.so