Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 6 Nov 2002 14:05:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 6 Nov 2002 14:05:50 -0500 Received: from rtlab.med.cornell.edu ([140.251.145.175]:63909 "HELO openlab.rtlab.org") by vger.kernel.org with SMTP id ; Wed, 6 Nov 2002 14:05:49 -0500 Date: Wed, 6 Nov 2002 14:12:28 -0500 (EST) From: "Calin A. Culianu" X-X-Sender: To: Subject: /prod/PID-related proc fs question Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1296 Lines: 33 I just noticed something today that I found odd and I know there must be a good reason for it, but I can't think of what it might be.. Basically if I am listing the contents of a /proc/PID directory, it seems that the cwd, exe, and root (symlink) entries are invalid unless the process corresponding to PID is a process owned by me, or I am root. Why is this? Is this feature security related? If so I can't really think of any security issues that would arise from having that information as a non-priviledged user. It would seem reasonable to me that users seeing each other's /prod/PID/root and /proc/PID/exe symlinks isn't really much of a security vulnerability.. Plus it would make possible a non-root user to grab statistics on the most popular running binaries, the number of chrooted processes.. etc.. probably trivial statistics but it still would be nice to see if any other instance of an application is running (unless there already is another mechanism for this that I am unaware of). Anyway any answers appreciated... -Calin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/