From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 28 May 2001 19:47:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 28 May 2001 19:46:56 -0400 Received: from yoda.planetinternet.be ([195.95.30.146]:10252 "EHLO yoda.planetinternet.be") by vger.kernel.org with ESMTP id ; Mon, 28 May 2001 19:46:39 -0400 Date: Tue, 29 May 2001 01:46:35 +0200 From: Kurt Roeckx To: Russell King Cc: Vadim Lebedev , linux-kernel@vger.kernel.org Subject: Re: Potenitial security hole in the kernel Message-ID: <20010529014635.A3499@ping.be> In-Reply-To: <003601c0e7bf$41953080$0101a8c0@LAP> <20010529001256.F9203@flint.arm.linux.org.uk> <20010529013030.A3381@ping.be> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <20010529013030.A3381@ping.be> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 29, 2001 at 01:30:30AM +0200, Kurt Roeckx wrote: > You should never "return" from userspace to kernelspace. The > only way to go from user space to kernel space should be by using > a system call. If you were able to return to kernel space, it already means you're running as kernel in the first place. There is no reason to even do the return in the first place. Kurt