[comp.unix.internals] kstuff 0.18

jfh@rpp386.cactus.org (John F Haugh II) (05/14/91)

In article <9105131716.AA17481@rodan.UU.NET>, kyle@UUNET.UU.NET writes:
> You did indeed post a fix.  But without the details, it's very
> hard for admins to come up with alternate solutions that don't
> impact their base of users and programs as much.  It's hard to
> close a hole if you don't know what it is.  Your proposed fixes
> might be complete and correct, but still not be the best for a
> particular installation.
> 
> Don't take this as another flame, it's not.  I'm just pointing
> out that reality often demands more than one solution to a
> problem.

One problem is that the changes that are needed really have to
be made by the vendors because the changes aren't the same for
every UNIX platform.  So he can't post a detailed fix.

On the other hand, posting the code that breaks into the system
will make it too easy on the programmers that haven't figured
it out yet and the vendors deserve a chance to get their butts
in gear.  My prediction is that Dan will post his code, a lot
of system will be broken into, and then Dan will be arrested
and hauled off to jail.  All because the vendors don't want to
be bothered.

Since this has sounded like a defense of Dan, I suppose I need
to attack him just to even things out ;-)  I've sent Dan a request
for his breakin suite (or whatever) and he hasn't provided it
yet.  I don't know if this is an oversight, or if he doesn't
believe that I actually work on AIX.
-- 
John F. Haugh II        | Distribution to  | UUCP: ...!cs.utexas.edu!rpp386!jfh
Ma Bell: (512) 255-8251 | GEnie PROHIBITED :-) |  Domain: jfh@rpp386.cactus.org
"If liberals interpreted the 2nd Amendment the same way they interpret the
 rest of the Constitution, gun ownership would be mandatory."

brnstnd@kramden.acf.nyu.edu (Dan Bernstein) (05/16/91)

In article <19274@rpp386.cactus.org> jfh@rpp386.cactus.org (John F Haugh II) writes:
> One problem is that the changes that are needed really have to
> be made by the vendors because the changes aren't the same for
> every UNIX platform.  So he can't post a detailed fix.

Fortunately (?), the holes were all inherited from the same place, so
the fixes are essentially the same on each platform. In fact, I haven't
heard of a (BSD-derived) system where my fixes don't work as is.

What would really simplify the fixes is to eliminate all kernel changes.
I have a (theoretically unreliable but in practice race-free) user-mode
opencount() for various systems, including SunOS, Ultrix, straight BSD,
DYNIX, et al., so on those systems it isn't necessary to implement
TIOCOPENCT inside the kernel, at least not at first. It turns out that
TIOCNOTTY already works on /dev/ttyxx on quite a few systems. That
leaves just one kernel change for those systems, namely implementing
/dev/stdtty. If someone can figure out a solution to /dev/tty that
doesn't involve kernel changes, it'll suddenly be possible to distribute
working patches even to sites without source.

> My prediction is that Dan will post his code, a lot
> of system will be broken into, and then Dan will be arrested
> and hauled off to jail.  All because the vendors don't want to
> be bothered.

Thank you for that pleasant thought.

> I've sent Dan a request
> for his breakin suite (or whatever) and he hasn't provided it
> yet.

Slow down, willya? I think it's more important to get the information to
vendors like Sun that still have the problem than to vendors like IBM
that (at least claim to) have fixed it.

---Dan