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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 77964C34965 for ; Fri, 13 Dec 2019 20:37:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B744124712 for ; Fri, 13 Dec 2019 20:37:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727761AbfLMOdK (ORCPT ); Fri, 13 Dec 2019 09:33:10 -0500 Received: from www262.sakura.ne.jp ([202.181.97.72]:61020 "EHLO www262.sakura.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727610AbfLMOdK (ORCPT ); Fri, 13 Dec 2019 09:33:10 -0500 Received: from fsav401.sakura.ne.jp (fsav401.sakura.ne.jp [133.242.250.100]) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTP id xBDEV8Eb079029; Fri, 13 Dec 2019 23:31:09 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Received: from www262.sakura.ne.jp (202.181.97.72) by fsav401.sakura.ne.jp (F-Secure/fsigk_smtp/550/fsav401.sakura.ne.jp); Fri, 13 Dec 2019 23:31:08 +0900 (JST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/fsav401.sakura.ne.jp) Received: from [192.168.1.9] (softbank126040062084.bbtec.net [126.40.62.84]) (authenticated bits=0) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTPSA id xBDEV807079026 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NO); Fri, 13 Dec 2019 23:31:08 +0900 (JST) (envelope-from penguin-kernel@i-love.sakura.ne.jp) Subject: Re: BUG: unable to handle kernel NULL pointer dereference in mem_serial_out To: Dmitry Vyukov , Greg KH , Linus Torvalds Cc: syzbot , Andy Shevchenko , asierra@xes-inc.com, ext-kimmo.rautkoski@vaisala.com, Jiri Slaby , kai heng feng , LKML , linux-serial , mika.westerberg@linux.intel.com, o.barta89@gmail.com, paulburton@kernel.org, sr@denx.de, syzkaller-bugs , yegorslists@googlemail.com References: <00000000000053539a0599173973@google.com> <20191212105701.GB1476206@kroah.com> <20191213093357.GB2135612@kroah.com> From: Tetsuo Handa Message-ID: <74859736-478a-6ad7-f0be-cfe87ec40ff5@i-love.sakura.ne.jp> Date: Fri, 13 Dec 2019 23:31:08 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/12/13 19:00, Dmitry Vyukov wrote: > Easier said than done. "normal user of the serial port" is not really > a thing in Linux, right? You either have CAP_SYS_ADMIN or not, that's > not per-device... > As far as I remember +Tetsuo proposed a config along the lines of > "restrict only things that legitimately cause damage under a fuzzer > workload", e.g. freezing filesystems, disabling console output, etc. > This may be another candidate. But I can't find where that proposal is > now. That suggestion got no response for two months. https://lkml.kernel.org/r/3e4e2b6b-7828-54ab-cf28-db1a396d7e20@i-love.sakura.ne.jp Unless we add such kernel config option to upstream kernels, it will become a whack-a-mole game.