Fragment of file phpsysinfo.ini.new:
.......
; Smartctl program
; If the smartctl program is available we can read S.M.A.R.T informations
; - "command" smartctl command is run everytime the block gets refreshed or build
; if error: Smartctl open device: /dev/sda failed: Permission denied
; Not recommended method:
; execute: chmod 4755 /usr/sbin/smartctl
; - "data" (a file must be available in the data directory of the
; phpsysinfo installation with the filename "smart{disk_number}.txt";
; content is the output from "smartctl --all device")
;
ACCESS="command"
......

chmod 4755 is sufficient, no need to do sudo