Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 9 Feb 2003 14:27:48 +0100
From:      Thomas Moestl <tmoestl@gmx.net>
To:        Tim Robbins <tjr@FreeBSD.org>
Cc:        Kris Kennaway <kris@obsecurity.org>, Morten Rodal <morten@rodal.no>, current@FreeBSD.org
Subject:   Re: Panic in fork()
Message-ID:  <20030209132747.GA638@crow.dom2ip.de>
In-Reply-To: <20030209143936.A2648@dilbert.robbins.dropbear.id.au>
References:  <20030208092406.GA12104@rot13.obsecurity.org> <20030208110512.GB12696@rot13.obsecurity.org> <20030208141542.GC11725@slurp.rodal.no> <20030208151226.GB624@crow.dom2ip.de> <20030208220456.GB15257@rot13.obsecurity.org> <20030209143936.A2648@dilbert.robbins.dropbear.id.au>

next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, 2003/02/09 at 14:39:36 +1100, Tim Robbins wrote:
> On Sat, Feb 08, 2003 at 02:04:56PM -0800, Kris Kennaway wrote:
> 
> > On Sat, Feb 08, 2003 at 04:12:26PM +0100, Thomas Moestl wrote:
> > 
> > > addr2line will usually point to the first line of a statement if it
> > > spans multiple lines; in this case, the full guard is:
> > > 
> > > 			while (p2->p_pid == trypid ||
> > > 			    p2->p_pgrp->pg_id == trypid ||
> > > 			    p2->p_session->s_sid == trypid) {
> > 
> > OK, I suspected that.
> > 
> > tjr was looking into this last night and proposed the following patch:
> 
> Alfred was the one who pointed out that holding proctree was probably
> necessary, though :-)

I don't really get why this is required - the pg_session pointer in
struct pgrp is constant over the pgrp's lifetime, so for it to be
invalid the wrong struct pgrp must be referenced; the p_pgrp pointer
is protected by the process lock however, which is held for this check.

	- Thomas

-- 
Thomas Moestl <tmoestl@gmx.net>	http://www.tu-bs.de/~y0015675/
              <tmm@FreeBSD.org>	http://people.FreeBSD.org/~tmm/
PGP fingerprint: 1C97 A604 2BD0 E492 51D0  9C0F 1FE6 4F1D 419C 776C

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030209132747.GA638>