kern/153938: [run] [panic] [patch] Workaround for use-after-free panic

[Juergen Lock]

The following reply was made to PR kern/153938; it has been noted by GNATS.

From: Juergen Lock <nox at jelal.kn-bremen.de>
To: PseudoCylon <moonlightakkiy at yahoo.ca>
Cc: Juergen Lock <nox at jelal.kn-bremen.de>, bug-followup at freebsd.org
Subject: Re: kern/153938: [run] [panic] [patch] Workaround for use-after-free
 panic
Date: Mon, 17 Jan 2011 22:14:04 +0100

 On Sun, Jan 16, 2011 at 10:24:07PM -0800, PseudoCylon wrote:
 
 > > [...]
 > >  I see you removed the rn->wcid code, I guess I should  have
 > > explained what it's for:  ni->ni_associd already gets zeroed  before
 > > run_node_cleanup() is called so with your version no  sc->sc_ni[wcid]
 > > ever gets set to NULL.
 > > 
 > 
 > You're right.
 > 
 > > +        if (wcid ==  0)
 > > +            wcid =  rn->wcid;
 > 
 > 
 > Is there any reason to test "ni->ni_associd == 0"? We know it is 0.
 
 Oh I only left it in in case the surrounding code changes in the
 future, but I guess that's pretty unlikely.  So I agree the check
 can be removed...