Why do you redirect tar's stderr to /dev/null?
I recommend passing these options to tar, so that the user's name/group/umask are not leaked:
--owner root --group root --mode a+rX Have you seen #685611? -- Jakub Wilk -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org