[net.unix-wizards] Xenix Crash? Trivial...

ignatz@aicchi.UUCP (Ihnat) (07/18/85)

Gosh, you have to go into a program?  I just discovered tonight, while
'adb'ing a stripped object (DON'T ask why I would want to do it--object
licensees have to do many things a respectable source licensee wouldn't
*dream* of), that I can trash the kernel by simply trying to single-step
through a system call!

I'm running Xenix 3.0b on an Altos 586.  I'm curious if this will happen
on an AT or XT, but please...backup and 'sync' your disks if you're willing
to attempt to make this sacrifice for the expansion of humankind's knowledge.

If you've an Altos running Xenix?  I dunno...maybe make 'adb' executable
only by root?  (heh, heh...)

	Dave "Damn, am I glad my 80-meg didn't get trashed" Ihnat
	Analysts International Corp.
	ihnp4!aicchi!ignatz
	ihnp4!aicchi!homebru!ignatz

-- 
	Dave Ihnat
	Analysts International Corporation
	(312) 882-4673
	ihnp4!aicchi!ignatz

tang@mulga.OZ (Antony Tang) (07/21/85)

In article <518@aicchi.UUCP> ignatz@aicchi.UUCP (Ihnat) writes:
>Gosh, you have to go into a program?  I just discovered tonight, while
>'adb'ing a stripped object (DON'T ask why I would want to do it--object
>licensees have to do many things a respectable source licensee wouldn't
>*dream* of), that I can trash the kernel by simply trying to single-step
>through a system call!
>

In the manual of XENIX 1.0 for the AT, it read  : "System calls cannot
be single-stepped"

ignatz@aicchi.UUCP (Ihnat) (07/24/85)

In article <831@mulga.OZ> of net.unix-wizards, Anthony Tang responds to
my comment in <518@aicchi.UUCP> :

>>Gosh, you have to go into a program?  I just discovered tonight, while
>>'adb'ing a stripped object (DON'T ask why I would want to do it--object
>>licensees have to do many things a respectable source licensee wouldn't
>>*dream* of), that I can trash the kernel by simply trying to single-step
>>through a system call!

with:

>In the manual of XENIX 1.0 for the AT, it read  : "System calls cannot
>be single-stepped"

Mmmm-hmmmm.  No argument; they (syscalls) shouldn't be.  BUT--should any
random, non-priviliged user--malicious or not--be able to trash the system
with such a trivial mistake?  I think not...oh, well...
-- 
	Dave Ihnat
	Analysts International Corporation
	(312) 882-4673
	ihnp4!aicchi!ignatz