From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760618AbYENLoR (ORCPT ); Wed, 14 May 2008 07:44:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757808AbYENLoG (ORCPT ); Wed, 14 May 2008 07:44:06 -0400 Received: from bipbip.grupopie.com ([195.23.16.24]:35521 "EHLO bipbip.grupopie.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756832AbYENLoF (ORCPT ); Wed, 14 May 2008 07:44:05 -0400 Message-ID: <482AD08D.7070206@grupopie.com> Date: Wed, 14 May 2008 12:44:13 +0100 From: Paulo Marques Organization: Grupo PIE User-Agent: Thunderbird 1.5.0.14 (X11/20071210) MIME-Version: 1.0 To: Vegard Nossum CC: akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kallsyms: fix potential overflow in binary search References: <20080513200736.GA17909@damson.getinternet.no> In-Reply-To: <20080513200736.GA17909@damson.getinternet.no> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vegard Nossum wrote: >>>From 61b840f071e496f632fcc293f5435428cfc98844 Mon Sep 17 00:00:00 2001 > From: Vegard Nossum > Date: Tue, 13 May 2008 10:20:27 +0200 > Subject: [PATCH] kallsyms: fix potential overflow in binary search > > This will probably never trigger... but it won't hurt to be careful. Not "probably", this will never trigger _period_. If you ever have more than 2^31 symbols in the kernel's kallsyms table you'll have worse problems to worry about than the binary search overflowing. So, I don't think it is worth this des-optimization at all... > http://googleresearch.blogspot.com/2006/06/extra-extra-read-all-about-it-nearly.html > > Signed-off-by: Vegard Nossum > --- > kernel/kallsyms.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c > index 6fc0040..38fc10a 100644 > --- a/kernel/kallsyms.c > +++ b/kernel/kallsyms.c > @@ -176,7 +176,7 @@ static unsigned long get_symbol_pos(unsigned long addr, > high = kallsyms_num_syms; > > while (high - low > 1) { > - mid = (low + high) / 2; > + mid = low + (high - low) / 2; > if (kallsyms_addresses[mid] <= addr) > low = mid; > else -- Paulo Marques - www.grupopie.com Dear aunt, let's set so double the killer delete select all. -- Microsoft voice recognition live demonstration