Kernel Rootkits

[Allison <fireflyblue@gmail.com>]

Hi,

I was curious about how kernel rootkits become a part of the kernel ?
One way I guess is by inserting a kernel module.  And rootkits also
manage to hide themselves from rootkit detectors.

few questions:
1. Are there any other ways by which rootkits become part of the kernel ?

2. If modules can access only exported symbols, how is it that kernel
rootkits manage to get hold of other information from the kernel ? For
ex, the process table.

I am not familiar with the /dev/kmem interface. Does this interface
let any kernel module read any symbol (even non-exported) from the
kernel ?

3. If I want to hide a function which is part of the kernel from
kernel modules, is this possible ideally ?

thanks,
Allison