K 10
svn:author
V 3
pjd
K 8
svn:date
V 27
2012-09-01T11:21:56.847278Z
K 7
svn:log
V 858
Fix panic in procdesc that can be triggered in the following scenario:

1. Process A pdfork(2)s process B.
2. Process A passes process descriptor of B to unrelated process C.
3. Hit CTRL+C to terminate process A. Process B is also terminated
   with SIGINT.
4. init(8) collects status of process B.
5. Process C closes process descriptor associated with process B.

When we have such order of events, init(8), by collecting status of
process B, will call procdesc_reap(). This function sets pd_proc to NULL.

Now when process C calls close on this process descriptor,
procdesc_close() is called. Unfortunately procdesc_close() assumes that
pd_proc points at a valid proc structure, but it was set to NULL earlier,
so the kernel panics.

The patch also adds setting 'p->p_procdesc' to NULL in procdesc_reap(),
which I think should be done.

MFC after:	1 week

END