É provável que as permissões em / tmp ainda estejam confusas.
Meu sistema de arquivos raiz no CentOS 5 é assim:
[8:21am][wlynch@apple ~] ls -al /
total 178
drwxr-xr-x 24 root root 4096 Feb 1 20:56 .
drwxr-xr-x 24 root root 4096 Feb 1 20:56 ..
-rw-r--r-- 1 root root 0 Feb 1 20:56 .autofsck
-rw-r--r-- 1 root root 0 Jan 25 14:55 .autorelabel
drwxr-xr-x 2 root root 4096 Feb 8 04:02 bin
drwxr-xr-x 4 root root 1024 Jan 25 15:21 boot
drwxr-xr-x 11 root root 3700 Feb 6 11:20 dev
drwxr-xr-x 106 root root 12288 Feb 8 04:02 etc
drwxr-xr-x 3 root root 4096 Jan 25 14:56 home
drwxr-xr-x 11 root root 4096 Jan 31 18:18 lib
drwxr-xr-x 8 root root 12288 Feb 8 04:02 lib64
drwx------ 2 root root 16384 Jan 25 08:44 lost+found
drwxr-xr-x 2 root root 4096 May 11 2011 media
drwxr-xr-x 2 root root 0 Feb 1 20:57 misc
drwxr-xr-x 3 root root 4096 Jan 25 20:01 mnt
drwxr-xr-x 2 root root 0 Feb 1 20:57 net
drwxr-xr-x 5 root root 4096 Jan 25 16:41 opt
dr-xr-xr-x 150 root root 0 Feb 1 14:56 proc
drwxr-x--- 7 root root 4096 Feb 6 11:21 root
drwxr-xr-x 2 root root 12288 Feb 8 04:02 sbin
drwxr-xr-x 2 root root 4096 Jan 25 14:45 selinux
drwxr-xr-x 2 root root 4096 May 11 2011 srv
drwxr-xr-x 11 root root 0 Feb 1 14:56 sys
drwxrwxrwt 15 root root 4096 Feb 8 08:20 tmp
drwxr-xr-x 15 root root 4096 Jan 25 14:47 usr
drwxr-xr-x 22 root root 4096 Jan 25 14:51 var