Possible security issue with missing files

From: Andrew Webb (andrew.webb_at_not-here.eme-med.co.uk)
Date: 05/08/03

Date: Thu, 8 May 2003 14:22:52 +0100


    We I have a server that is low on disk space in /var - the output of
'df -h' is

[root@eme-uk-its1 var]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/rd/c0d0p6 496M 263M 208M 56% /
/dev/rd/c0d0p1 97M 32M 60M 35% /boot
/dev/rd/c0d0p5 3.8G 36M 3.5G 1% /home
none 251M 0 250M 0% /dev/shm
/dev/rd/c0d0p2 10G 4.0G 5.8G 41% /usr
/dev/rd/c0d0p7 1008M 788M 169M 83% /var

If I run 'du -H' I get

... (listings for the dirs and sizes)
125MB .

This shows a usage of 125 MB whereas df shows 788MB in use ? Is there some
security issue here on file permissions that might be causing this
difference in value ?