[PATCH] SYSV IPC ABI rototill

[Alfred Perlstein]

* John Baldwin <jhb at freebsd.org> [090623 14:07] wrote:
> On Tuesday 23 June 2009 4:52:09 pm Dag-Erling Sm??rgrav wrote:
> > John Baldwin <jhb at freebsd.org> writes:
> > > There have been a several issues with the existing ABI of the SYSV IPC 
> > > structures over the past several years and it has been on the todo list for 
> > > at least both 7.0 and 8.0.  Rather than putting it off until 9.0 I sat down 
> > > and worked on it this week.
> > 
> > Have you given any thought to virtualization, i.e. separate namespaces
> > for each jail?  Will your patch make this any easier or harder to
> > implement?
> 
> It likely has zero effect on that.  The global variables one would need to
> virtualize are unchanged by this.

John, would it make sense to check for overflow in ipcperm_new2old and return
some error so that callers get back some nasty error so that they don't make
a mistake about permissions when an overflow happens?

A crash/error sounds better than silent truncating of credential information,
but I could be wrong.

-Alfred