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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 8697DC433E2 for ; Tue, 19 May 2020 14:32:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6EBEF20849 for ; Tue, 19 May 2020 14:32:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729152AbgESOcv (ORCPT ); Tue, 19 May 2020 10:32:51 -0400 Received: from mail-oi1-f194.google.com ([209.85.167.194]:46918 "EHLO mail-oi1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726203AbgESOcv (ORCPT ); Tue, 19 May 2020 10:32:51 -0400 Received: by mail-oi1-f194.google.com with SMTP id b3so4520765oib.13; Tue, 19 May 2020 07:32:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=abHSSr+FE4mwVPeVCc+1hZ1CV3QH4VBasK3yRu00G8w=; b=oaGeqlKaZ8FujpIeSZRhUs2PoG3Asm4GAYsfjiPkX/1z0yAOmVTWfRupmy0oBAo+TX OW45xYUeqiu0lQKTSUrt6Zm0VGfDPCMiP9nsRoIWM035WlIhBs5Ej4PiCvhgRaNiwHPP A1eMWyliH2kOImfaUXGJ3PNH5zHKeCWeqjDi/VCJkDIDPeafVp6pbg0Lds0oJqNNpT49 S+7wppebosENFswBh80N9hLcqi6yVKXsY1iSdu9uhQtnmLOyikSnNf2XPjn/HI6e0agK RpjIVpEbNsYyASpi1JsRB2YpIw8Fx/w9M6xlZl88oZOPUS2S3Ls8rcT2f+YnE154dPw/ 7LWA== X-Gm-Message-State: AOAM533eCqVK6uiruvhbB1qoigSo+dmoUfm/W4e7rQNyZ94WFgtixhsP vk9hYblhSfKrL27X4DLKvcaXE53tA1EzYHwe0Cw= X-Google-Smtp-Source: ABdhPJx5xpaNUb44KFms9IJ3GzKK63OnX4HawXvL1bIDgomSjsEfyzELox7IqozrkRT0A93QxuZvt9nAfcPrRCUr8bQ= X-Received: by 2002:aca:cd93:: with SMTP id d141mr3227937oig.148.1589898770045; Tue, 19 May 2020 07:32:50 -0700 (PDT) MIME-Version: 1.0 References: <20200518055457.12302-1-keescook@chromium.org> <20200518055457.12302-2-keescook@chromium.org> <20200518130251.zih2s32q2rxhxg6f@wittgenstein> <20200518144627.sv5nesysvtgxwkp7@wittgenstein> <87blmk3ig4.fsf@x220.int.ebiederm.org> <87mu64uxq1.fsf@igel.home> <87sgfwuoi3.fsf@x220.int.ebiederm.org> <20200519131341.qiysndpmj75zfjtz@wittgenstein> In-Reply-To: <20200519131341.qiysndpmj75zfjtz@wittgenstein> From: Geert Uytterhoeven Date: Tue, 19 May 2020 16:32:38 +0200 Message-ID: Subject: Re: [PATCH 1/4] exec: Change uselib(2) IS_SREG() failure to EACCES To: Christian Brauner Cc: "Eric W. Biederman" , Andreas Schwab , Jann Horn , Kees Cook , Al Viro , Andrew Morton , Tetsuo Handa , Eric Biggers , Dmitry Vyukov , linux-fsdevel , linux-security-module , Linux API , kernel list Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Hi Christian, On Tue, May 19, 2020 at 3:15 PM Christian Brauner wrote: > On Tue, May 19, 2020 at 06:56:36AM -0500, Eric W. Biederman wrote: > > Andreas Schwab writes: > > > On Mai 18 2020, Eric W. Biederman wrote: > > >> If it was only libc4 and libc5 that used the uselib system call then it > > >> can probably be removed after enough time. > > > > > > Only libc4 used it, libc5 was already ELF. > > > > binfmt_elf.c supports uselib. In a very a.out ish way. Do you know if > > that support was ever used? > > > > If we are truly talking a.out only we should be able to make uselib > > conditional on a.out support in the kernel which is strongly mostly > > disabled at this point. > > The only ones that even allow setting AOUT: > > arch/alpha/Kconfig: select HAVE_AOUT > arch/m68k/Kconfig: select HAVE_AOUT if MMU > > and x86 deprecated it March 2019: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eac616557050737a8d6ef6fe0322d0980ff0ffde Quoting myself (for the second time this month): "I think it's safe to assume no one still runs a.out binaries on m68k." http://lore.kernel.org/r/CAMuHMdW+m0Q+j3rsQdMXnrEPm+XB5Y2AQrxW5sD1mZAKgmEqoA@mail.gmail.com Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds