Introduce a new lock, hostname_mtx, and use it to synchronize access

to global hostname and domainname variables.  Where necessary, copy
to or from a stack-local buffer before performing copyin() or
copyout().  A few uses, such as in cd9660 and daemon_saver, remain
under-synchronized and will require further updates.

Correct a bug in which a failed copyin() of domainname would leave
domainname potentially corrupted.

MFC after:	3 weeks

0 files changed, 0 insertions, 0 deletions