From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B03CCC10F0E for ; Thu, 18 Apr 2019 06:08:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 881D4204FD for ; Thu, 18 Apr 2019 06:08:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731304AbfDRGIJ (ORCPT ); Thu, 18 Apr 2019 02:08:09 -0400 Received: from relay7-d.mail.gandi.net ([217.70.183.200]:37055 "EHLO relay7-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725876AbfDRGIJ (ORCPT ); Thu, 18 Apr 2019 02:08:09 -0400 X-Originating-IP: 79.86.19.127 Received: from [192.168.0.11] (127.19.86.79.rev.sfr.net [79.86.19.127]) (Authenticated sender: alex@ghiti.fr) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id D89BD20008; Thu, 18 Apr 2019 06:08:02 +0000 (UTC) Subject: Re: [PATCH v3 09/11] mips: Use STACK_TOP when computing mmap base address To: Kees Cook Cc: Andrew Morton , Christoph Hellwig , Russell King , Catalin Marinas , Will Deacon , Ralf Baechle , Paul Burton , James Hogan , Palmer Dabbelt , Albert Ou , Alexander Viro , Luis Chamberlain , LKML , linux-arm-kernel , linux-mips@vger.kernel.org, linux-riscv@lists.infradead.org, "linux-fsdevel@vger.kernel.org" , Linux-MM References: <20190417052247.17809-1-alex@ghiti.fr> <20190417052247.17809-10-alex@ghiti.fr> From: Alex Ghiti Message-ID: <16ed1829-a7ad-76b9-2929-9eb14406da00@ghiti.fr> Date: Thu, 18 Apr 2019 02:08:02 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: sv-FI Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 4/18/19 1:31 AM, Kees Cook wrote: > On Wed, Apr 17, 2019 at 12:32 AM Alexandre Ghiti wrote: >> mmap base address must be computed wrt stack top address, using TASK_SIZE >> is wrong since STACK_TOP and TASK_SIZE are not equivalent. >> >> Signed-off-by: Alexandre Ghiti > Acked-by: Kees Cook Thanks ! > > -Kees > >> --- >> arch/mips/mm/mmap.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/arch/mips/mm/mmap.c b/arch/mips/mm/mmap.c >> index 3ff82c6f7e24..ffbe69f3a7d9 100644 >> --- a/arch/mips/mm/mmap.c >> +++ b/arch/mips/mm/mmap.c >> @@ -22,7 +22,7 @@ EXPORT_SYMBOL(shm_align_mask); >> >> /* gap between mmap and stack */ >> #define MIN_GAP (128*1024*1024UL) >> -#define MAX_GAP ((TASK_SIZE)/6*5) >> +#define MAX_GAP ((STACK_TOP)/6*5) >> #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) >> >> static int mmap_is_legacy(struct rlimit *rlim_stack) >> @@ -54,7 +54,7 @@ static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) >> else if (gap > MAX_GAP) >> gap = MAX_GAP; >> >> - return PAGE_ALIGN(TASK_SIZE - gap - rnd); >> + return PAGE_ALIGN(STACK_TOP - gap - rnd); >> } >> >> #define COLOUR_ALIGN(addr, pgoff) \ >> -- >> 2.20.1 >> >