From owner-freebsd-fs  Tue Oct 28 07:34:21 1997
Return-Path: <owner-freebsd-fs>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id HAA29308
          for fs-outgoing; Tue, 28 Oct 1997 07:34:21 -0800 (PST)
          (envelope-from owner-freebsd-fs)
Received: from mailer.zib.de (mailer.zib.de [130.73.108.11])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id HAA29189
          for <freebsd-fs@FreeBSD.ORG>; Tue, 28 Oct 1997 07:33:49 -0800 (PST)
          (envelope-from wolfram@softs11.zib.de)
Received: from soft13.zib.de (soft13.zib.de [130.73.63.13] (may be forged))
	by mailer.zib.de (8.8.7/8.8.7) with SMTP id QAA18146;
	Tue, 28 Oct 1997 16:33:20 +0100 (MET)
Received: by soft13.zib.de (SMI-8.6/SMI-SVR4)
	id QAA04035; Tue, 28 Oct 1997 16:33:19 +0100
Date: Tue, 28 Oct 1997 16:33:19 +0100
Message-Id: <199710281533.QAA04035@soft13.zib.de>
From: Wolfram Schneider <schneider@zib.de>
To: Ollivier Robert <roberto@keltia.freenix.fr>
Cc: freebsd-fs@FreeBSD.ORG
Subject: Re: disabled symlinks
In-Reply-To: <19971027001140.31561@keltia.freenix.fr>
References: <199710261041.LAA00556@panke.panke.de>
	<19971027001140.31561@keltia.freenix.fr>
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
Sender: owner-freebsd-fs@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

Ollivier Robert writes:
>According to Wolfram Schneider:
>> The nosymlink flag do not allow the creation of a symlink
>> on the mounted file system.
>Could you please modify your patch not to _follow_ symlinks in order to
>disallow all symlinks in a given FS ?


The patch return 'Permission denied' for symlinks in the
kernel function namei/lookup.

Index: vfs_lookup.c
===================================================================
RCS file: /usr/cvs/src/sys/kern/vfs_lookup.c,v
retrieving revision 1.11.4.1
diff -u -r1.11.4.1 vfs_lookup.c
--- vfs_lookup.c	1996/12/03 15:48:25	1.11.4.1
+++ vfs_lookup.c	1997/10/27 14:51:56
@@ -493,6 +493,10 @@
 	    ((cnp->cn_flags & FOLLOW) || trailing_slash ||
 	     *ndp->ni_next == '/')) {
 		cnp->cn_flags |= ISSYMLINK;
+		if (dp->v_mount->mnt_flag & MNT_NOSYMLINK) {
+			error = EACCES;
+			goto bad2;
+		}
 		return (0);
 	}