From owner-freebsd-questions  Mon Apr  2 14:25:41 2001
Delivered-To: freebsd-questions@freebsd.org
Received: from neko.cts.com (neko.cts.com [209.68.192.150])
	by hub.freebsd.org (Postfix) with ESMTP id 7802D37B727
	for <freebsd-questions@FreeBSD.ORG>; Mon,  2 Apr 2001 14:25:37 -0700 (PDT)
	(envelope-from ctsmhn@cts.com)
Received: from CARTMAN (cartman.cts.com [205.163.23.192])
	by neko.cts.com (8.9.3/8.9.3) with SMTP id OAA17975;
	Mon, 2 Apr 2001 14:25:36 -0700 (PDT)
From: "Matthew H. North" <ctsmhn@cts.com>
To: "Jeremiah Gowdy" <jgowdy@home.com>,
	<freebsd-questions@FreeBSD.ORG>
Subject: RE: Reproducible kernel panics, 4.2-STABLE, various hardware
Date: Mon, 2 Apr 2001 14:29:32 -0700
Message-ID: <LAEKJNMMIOPFCDDPFBDEKEBICBAA.ctsmhn@cts.com>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: 7bit
X-Priority: 3 (Normal)
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0)
X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700
In-Reply-To: <006b01c0bbb7$baed3150$035778d8@sherline.net>
Importance: Normal
Sender: owner-freebsd-questions@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.ORG


| That's not true though.  Userland programs running as root can
| cause kernel
| panics and hard lockups.  :)

Interesting.  Is that because root-running programs have direct access to
hardware and BIOS?  Or is this true even if the program only uses system
calls to get anything low-level done?

In any event, the way squid works is it starts as root and establishes
itself as a parent process, then spawns a child that uses seteuid (and
setegid) to run as an unprivileged user.  The root-running parent just
watches its single child and spawns a new one should it die.  That should
make the point moot.

But I was just looking at the squid code and it appears that it has a
function that changes uid back to 0.  Not sure if children are allowed to
use that function or not.  Just another ? ... sigh.

|
| Have you tried CVSUPing to 4.3-RC and seeing if it does it there?

I have not - I'll have to try that next I suppose.

- Matt


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