Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262448AbVESCqO (ORCPT ); Wed, 18 May 2005 22:46:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262454AbVESCqO (ORCPT ); Wed, 18 May 2005 22:46:14 -0400 Received: from fire.osdl.org ([65.172.181.4]:52705 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S262448AbVESCqK (ORCPT ); Wed, 18 May 2005 22:46:10 -0400 Date: Wed, 18 May 2005 19:47:57 -0700 (PDT) From: Linus Torvalds To: Rik van Riel cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH] prevent NULL mmap in topdown model In-Reply-To: Message-ID: References: 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: 981 Lines: 28 On Wed, 18 May 2005, Rik van Riel wrote: > > On Wed, 18 May 2005, Linus Torvalds wrote: > > > Why not just change the "addr >= len" test into "addr > len" and be done > > with it? > > If you're fine with not catching dereferences of a struct > member further than PAGE_SIZE into a struct when the struct > pointer is NULL, sure ... I'm certainly ok with that, especially since it should never be a problem in practice (ie the virtual memory map getting so full that we even get to these low allocations should be basically something that never happens under normal load). However, it would be good to have even the trivial patch tested. Especially since what it tries to fix is a total corner-case in the first place.. Linus - 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/