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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 75DB7C433E0 for ; Wed, 20 May 2020 13:06:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5118A206BE for ; Wed, 20 May 2020 13:06:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726812AbgETNGm (ORCPT ); Wed, 20 May 2020 09:06:42 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:39646 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726435AbgETNGk (ORCPT ); Wed, 20 May 2020 09:06:40 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out03.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jbOQc-0007Zb-8X; Wed, 20 May 2020 07:06:34 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jbOQb-0006Q7-Dy; Wed, 20 May 2020 07:06:34 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Kees Cook Cc: linux-kernel@vger.kernel.org, Linus Torvalds , Oleg Nesterov , Jann Horn , Greg Ungerer , Rob Landley , Bernd Edlinger , linux-fsdevel@vger.kernel.org, Al Viro , Alexey Dobriyan , Andrew Morton , Casey Schaufler , linux-security-module@vger.kernel.org, James Morris , "Serge E. Hallyn" , Andy Lutomirski , Christoph Hellwig References: <87h7wujhmz.fsf@x220.int.ebiederm.org> <87sgga6ze4.fsf@x220.int.ebiederm.org> <87v9l4zyla.fsf_-_@x220.int.ebiederm.org> <877dx822er.fsf_-_@x220.int.ebiederm.org> <202005191442.515A0ED@keescook> Date: Wed, 20 May 2020 08:02:51 -0500 In-Reply-To: <202005191442.515A0ED@keescook> (Kees Cook's message of "Tue, 19 May 2020 14:55:49 -0700") Message-ID: <87r1vekbd0.fsf@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1jbOQb-0006Q7-Dy;;;mid=<87r1vekbd0.fsf@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX19uA8zRl9AyhKnD0V7yz6o0yeiwCD3dOiE= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH v2 0/8] exec: Control flow simplifications X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Kees Cook writes: > On Mon, May 18, 2020 at 07:29:00PM -0500, Eric W. Biederman wrote: >> arch/alpha/kernel/binfmt_loader.c | 11 +---- >> fs/binfmt_elf.c | 4 +- >> fs/binfmt_elf_fdpic.c | 4 +- >> fs/binfmt_em86.c | 13 +---- >> fs/binfmt_misc.c | 69 ++++----------------------- >> fs/binfmt_script.c | 82 ++++++++++++++------------------ >> fs/exec.c | 97 ++++++++++++++++++++++++++------------ >> include/linux/binfmts.h | 36 ++++++-------- >> include/linux/lsm_hook_defs.h | 3 +- >> include/linux/lsm_hooks.h | 52 +++++++++++--------- >> include/linux/security.h | 14 ++++-- >> kernel/cred.c | 3 ++ >> security/apparmor/domain.c | 7 +-- >> security/apparmor/include/domain.h | 2 +- >> security/apparmor/lsm.c | 2 +- >> security/commoncap.c | 9 ++-- >> security/security.c | 9 +++- >> security/selinux/hooks.c | 8 ++-- >> security/smack/smack_lsm.c | 9 ++-- >> security/tomoyo/tomoyo.c | 12 ++--- >> 20 files changed, 202 insertions(+), 244 deletions(-) > > Oh, BTW, heads up on this (trivially but annoyingly) conflicting with > the copy_strings_kernel/copy_string/kernel change: > > https://ozlabs.org/~akpm/mmotm/broken-out/exec-simplify-the-copy_strings_kernel-calling-convention.patch > > Is it worth pulling that and these into your tree? > > https://ozlabs.org/~akpm/mmotm/broken-out/exec-open-code-copy_string_kernel.patch > > https://ozlabs.org/~akpm/mmotm/broken-out/umh-fix-refcount-underflow-in-fork_usermode_blob.patch Good question. It is part of the greater set_fs removal work, and I don't want to mess that up. I would love to give copy_string_kernel a length parameter so binfmt_script did not have to modify it's buffer or copy the string, before calling copy_string_kernel. Hmm. I already have to call strdup on i_name in brpm_change_interp. So I probably just want to bite the bullet and figure out a way to do strdup earlier. So unless it makes things easier for Andrew I think it is probably easier to live with the conflict for now, and use this conversation as inspiration for my next round of cleanups of binfmt_misc. Eric