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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 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 62F1BC433DB for ; Wed, 3 Feb 2021 20:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03ED064F41 for ; Wed, 3 Feb 2021 20:26:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231873AbhBCUZ6 (ORCPT ); Wed, 3 Feb 2021 15:25:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:50056 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231215AbhBCUZ5 (ORCPT ); Wed, 3 Feb 2021 15:25:57 -0500 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 5F5BA64F6C; Wed, 3 Feb 2021 20:25:15 +0000 (UTC) Date: Wed, 3 Feb 2021 15:25:13 -0500 From: Steven Rostedt To: Kees Cook Cc: Timur Tabi , Petr Mladek , Sergey Senozhatsky , linux-kernel@vger.kernel.org, vbabka@suse.cz, linux-mm@kvack.org, willy@infradead.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, roman.fietze@magna.com, john.ogness@linutronix.de, Andy Shevchenko , Rasmus Villemoes , akinobu.mita@gmail.com Subject: Re: [PATCH][RESEND] lib/vsprintf: make-printk-non-secret printks all addresses as unhashed Message-ID: <20210203152513.34492916@gandalf.local.home> In-Reply-To: <202102031201.FFED9547D@keescook> References: <20210202213633.755469-1-timur@kernel.org> <19c1c17e-d0b3-326e-97ec-a4ec1ebee749@kernel.org> <202102031201.FFED9547D@keescook> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 3 Feb 2021 12:02:05 -0800 Kees Cook wrote: > On Wed, Feb 03, 2021 at 12:58:41PM -0600, Timur Tabi wrote: > > On 2/3/21 7:31 AM, Petr Mladek wrote: > > > Also please make sure that lib/test_printf.c will work with > > > the new option. > > > > As you suspected, it doesn't work: > > > > [ 206.966478] test_printf: loaded. > > [ 206.966528] test_printf: plain 'p' does not appear to be hashed > > [ 206.966740] test_printf: failed 1 out of 388 tests > > > > What should I do about this? > > > > On one hand, it is working as expected: %p is not hashed, and that should be > > a warning. > > > > On the other hand, maybe test_printf should be aware of the command line > > parameter and test to make sure that %p is NOT hashed? > > It seems like it'd be best for the test to fail, yes? It _is_ a problem > that %p is unhashed; it's just that the failure was intended. > I disagree. With a big notice that all pointers of unhashed, I don't think we need to print it failed when we expect it to fail. If anything, skip the test and state: test_printf: hash test skipped because "make-printk-non-secret" is on the command line. -- Steve