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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 57CC1C63699 for ; Sat, 14 Nov 2020 06:52:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1C4922227F for ; Sat, 14 Nov 2020 06:52:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="pGs1Q5ED" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726519AbgKNGwE (ORCPT ); Sat, 14 Nov 2020 01:52:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:33502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726133AbgKNGwE (ORCPT ); Sat, 14 Nov 2020 01:52:04 -0500 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 313B922282; Sat, 14 Nov 2020 06:52:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605336723; bh=KOEu7SPo3dHDOVfsJrzFpcbuRAiGkAnaqEgRozzrBSg=; h=Date:From:To:Subject:In-Reply-To:From; b=pGs1Q5EDDXY+6CXUasClnK9pSqkMcTimVvM6lGOrZ4NjJm1XxBA1z/3lbAdzosl0P cWZYEwHqupMu7JZkG5T41aFZm2O4AwZEtPqpPEd+jRYxWP14+YFXRuFpLrYF8ZguJ6 9CRdsPjLlW9yMmWEQLwVlUM7gNHWuzBNjEwfqKUY= Date: Fri, 13 Nov 2020 22:52:02 -0800 From: Andrew Morton To: akpm@linux-foundation.org, arnd@arndb.de, fabf@skynet.be, gregkh@linuxfoundation.org, keescook@chromium.org, linux-mm@kvack.org, linux@roeck-us.net, mcroce@microsoft.com, mm-commits@vger.kernel.org, pasha.tatashin@soleen.com, pmladek@suse.com, robinmholt@gmail.com, rppt@kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 08/14] Revert "kernel/reboot.c: convert simple_strtoul to kstrtoint" Message-ID: <20201114065202.FWrl0Eulf%akpm@linux-foundation.org> In-Reply-To: <20201113225115.b24faebc85f710d5aff55aa7@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Matteo Croce Subject: Revert "kernel/reboot.c: convert simple_strtoul to kstrtoint" Patch series "fix parsing of reboot= cmdline", v3. The parsing of the reboot= cmdline has two major errors: - a missing bound check can crash the system on reboot - parsing of the cpu number only works if specified last Fix both. This patch (of 2): This reverts commit 616feab753972b97. kstrtoint() and simple_strtoul() have a subtle difference which makes them non interchangeable: if a non digit character is found amid the parsing, the former will return an error, while the latter will just stop parsing, e.g. simple_strtoul("123xyx") = 123. The kernel cmdline reboot= argument allows to specify the CPU used for rebooting, with the syntax `s####` among the other flags, e.g. "reboot=warm,s31,force", so if this flag is not the last given, it's silently ignored as well as the subsequent ones. Link: https://lkml.kernel.org/r/20201103214025.116799-2-mcroce@linux.microsoft.com Fixes: 616feab75397 ("kernel/reboot.c: convert simple_strtoul to kstrtoint") Signed-off-by: Matteo Croce Cc: Guenter Roeck Cc: Petr Mladek Cc: Arnd Bergmann Cc: Mike Rapoport Cc: Kees Cook Cc: Pavel Tatashin Cc: Robin Holt Cc: Fabian Frederick Cc: Greg Kroah-Hartman Cc: Signed-off-by: Andrew Morton --- kernel/reboot.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) --- a/kernel/reboot.c~revert-kernel-rebootc-convert-simple_strtoul-to-kstrtoint +++ a/kernel/reboot.c @@ -551,22 +551,15 @@ static int __init reboot_setup(char *str break; case 's': - { - int rc; - - if (isdigit(*(str+1))) { - rc = kstrtoint(str+1, 0, &reboot_cpu); - if (rc) - return rc; - } else if (str[1] == 'm' && str[2] == 'p' && - isdigit(*(str+3))) { - rc = kstrtoint(str+3, 0, &reboot_cpu); - if (rc) - return rc; - } else + if (isdigit(*(str+1))) + reboot_cpu = simple_strtoul(str+1, NULL, 0); + else if (str[1] == 'm' && str[2] == 'p' && + isdigit(*(str+3))) + reboot_cpu = simple_strtoul(str+3, NULL, 0); + else *mode = REBOOT_SOFT; break; - } + case 'g': *mode = REBOOT_GPIO; break; _