> I really don't see where this is a problem. User level processing does not
> need
> hardware memory protection; it could be implemented as a strictly software
> solution. For example, a table defined within the OS giving the user and the
> level. Then, all memory access could interrogate this table and give pseudo
> memory level security.
And how are you going to make sure the program you are about to execute
isn't going to do anything malicious ?? Rewrite kernel CS, DS, other
programs' memory space, interrupt table or something else ?? By software
control ??? How are you going to find out whether the binary you are
attempting to run uses standard library calls or not (= uses some other
code that violates system integrity) ?? Such code can be hidden in less
than 50 bytes of code and covered pretty good. Any user can write
ownprogram that allows him to rewrite important structures in memory
(kernel DS) and thereby give him root access or just hang the system.
bye, Ab
