[BLUG] Unix conventions for controlling file access

[Steven Black]

As others have said, this technique is decades old. There is nothing harmful
about it.

This technique is older than Linux, let alone the Ext2 file-system. Every
file-system for Linux has to support this, as it is an inherent
characteristic of Unix-like file-systems and our ability to do upgrades of
live systems (and perform rm -r / and actually delete everything).

Most security measures are about reducing risk. If you only have a temp. file
as an open-able file for a short period of time, it reduces the risk of
others snooping it on you. -- Especially when the names are picked truly
randomly.

Cheers,
Steven Black

On Fri, Jul 13, 2007 at 04:05:49PM +0000, Mark Krenz wrote:
> # lsof | grep deleted
> [snip]
> mysqld    31958        mysql    7u   REG        9,0        0         15 /tmp/ibwZfdKe (deleted)
> mysqld    31958        mysql   13u   REG        9,0        0         16 /tmp/ibR0K4tQ (deleted)
> mysqld    31959        mysql    6u   REG        9,0        0         14 /tmp/ibuPNjWc (deleted)
> mysqld    31959        mysql    7u   REG        9,0        0         15 /tmp/ibwZfdKe (deleted)
> mysqld    31959        mysql   13u   REG        9,0        0         16 /tmp/ibR0K4tQ (deleted)