From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Philipp Stephani Newsgroups: gmane.emacs.devel Subject: Re: Skipping unexec via a big .elc file Date: Mon, 24 Oct 2016 16:51:20 +0000 Message-ID: References: <87eg51ng4r.fsf_-_@users.sourceforge.net> <87k2djwumn.fsf@users.sourceforge.net> <83h98nidvd.fsf@gnu.org> <87eg3rvtsf.fsf@users.sourceforge.net> <83k2dihpm9.fsf@gnu.org> <8760p2wzgj.fsf@users.sourceforge.net> <838ttyhhzu.fsf@gnu.org> <871szqwu51.fsf@users.sourceforge.net> <831szqhbc2.fsf@gnu.org> <87d1itt79z.fsf_-_@users.sourceforge.net> <7baa18d4-2b09-caa8-005e-29008a383ad1@cs.ucla.edu> <83mvhwrgd5.fsf@gnu.org> <8539f38f-9a11-44c3-4de7-bb974c96206c@cs.ucla.edu> <8360ojpndr.fsf@gnu.org> <83shrnm0k1.fsf@gnu.org> <83insi5jy9.fsf@gnu.org> <83mvht50qb.fsf@gnu.org> <8c085c3e-361d-7d10-6f34-07c387eb3b43@dancol.org> <83a8dt4u3a.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=089e0122f07c25f684053f9f34c6 X-Trace: blaine.gmane.org 1477328300 2753 195.159.176.226 (24 Oct 2016 16:58:20 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 24 Oct 2016 16:58:20 +0000 (UTC) Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Daniel Colascione , Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Oct 24 18:58:16 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1byiZR-0006p9-JH for ged-emacs-devel@m.gmane.org; Mon, 24 Oct 2016 18:57:57 +0200 Original-Received: from localhost ([::1]:48235 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byiZT-0005Ln-Vh for ged-emacs-devel@m.gmane.org; Mon, 24 Oct 2016 12:58:00 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:47241) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1byiTJ-00075G-2Z for emacs-devel@gnu.org; Mon, 24 Oct 2016 12:51:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1byiTH-0007SM-MI for emacs-devel@gnu.org; Mon, 24 Oct 2016 12:51:37 -0400 Original-Received: from mail-wm0-x22d.google.com ([2a00:1450:400c:c09::22d]:38462) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1byiTF-0007R3-DD; Mon, 24 Oct 2016 12:51:33 -0400 Original-Received: by mail-wm0-x22d.google.com with SMTP id c78so125628753wme.1; Mon, 24 Oct 2016 09:51:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=XtrfjqEHX/M72WgILHL3KLkPn9HwNVeWpkpJwlAwnoo=; b=cKpkzKDOvMuuPlH9du6w+ocQUTQLrvikQ9Ho7sW4TIrSdnfyNdYcSKH/IGvRj19UZz 0e3iOCePWSQgvVp6tJwKafwfhNmRJn4dcofzWQHcQe8uSYvkczOIoiVqbVJSbrMexM2h QFeHiKfp2OFBZO1H3mH2ZrG+uQeqQEEh5B5EnAl0W20uXdarDBwNks18xT0rv3ztvWQb NlSu9gqFWeGKYhoGB61+1Cgo9A1F+r5Wz8blaF6EbSHoE8G/JPOcfRMqx04Z2lRyJcZS x7IwEXR9WMkp2l9xqqpaDjtf0OsMK8pc01u76bFZNbisi5zfg4bjDpasWzVhfbBmxKat IBiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=XtrfjqEHX/M72WgILHL3KLkPn9HwNVeWpkpJwlAwnoo=; b=JPTf8tqdZtSNHGkrBse9LexzG9l2FeURaLG/0P1N2f2m2W/m6PO1dI/7ts+a7FFeJv c8HQZEUQXpcP7mRxGawZwlGOWCfsj5UpVPlduQhnKyfc7KyyKWzA6I+4uA3WWxMhzd0p xbmbkdRxzKpQmicePK6bcTM2mIX6R0HFWVl8w0FSMN6s6iVakqDhEtRAGR4DsNEva0DR HHkdZEatdsgLjUsLdhRkTg5LAJAoKUjnuAa8KQyvaX6ThvwK2JGVcYjOyG23YIgo5UxW tcSCzcsc5CqvGMNz7iCH59tMECkNVs5DnpL+tXfA8HQ1EumhNXLn9+Zp1JjArOO07yWQ DiXA== X-Gm-Message-State: ABUngvfdBmlbJH7QoYkHkXFOcQPUWh04zlUxQXH1IvBAyFjXXLJN4Eu1nLZft3D6TGcnV4cyIRwwOwl2wFP+OQ== X-Received: by 10.194.170.163 with SMTP id an3mr12971612wjc.73.1477327890804; Mon, 24 Oct 2016 09:51:30 -0700 (PDT) In-Reply-To: X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:400c:c09::22d X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:208725 Archived-At: --089e0122f07c25f684053f9f34c6 Content-Type: text/plain; charset=UTF-8 Daniel Colascione schrieb am Mo., 24. Okt. 2016 um 18:35 Uhr: > That is, we *could* get into a situation where "no people on board [] > know enough about unexec to solve the next problem" I'd argue that we are already in this situation. For example, nobody knows how to make unexec work with ASLR or PIE; when I tried fuzzing Emacs with AFL, the dumped binary would simply crash; the dumped binary is not reproducible (i.e. bit-by-bit identical after every build); and I think dumping also doesn't work with ASan. The fraction of situation where unexec doesn't work any more gets larger and larger. If we had people who could solve these problems, it should get smaller instead. --089e0122f07c25f684053f9f34c6 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


Daniel= Colascione <dancol@dancol.org&= gt; schrieb am Mo., 24. Okt. 2016 um 18:35=C2=A0Uhr:
That is, we *could* get into a situation where "no p= eople on board []
know enough about unexec to solve the next problem"
<= br>
I'd argue that we are already in this situation.=C2=A0 Fo= r example, nobody knows how to make unexec work with ASLR or PIE; when I tr= ied fuzzing Emacs with AFL, the dumped binary would simply crash; the dumpe= d binary is not reproducible (i.e. bit-by-bit identical after every build);= and I think dumping also doesn't work with ASan. The fraction of situa= tion where unexec doesn't work any more gets larger and larger. If we h= ad people who could solve these problems, it should get smaller instead.
--089e0122f07c25f684053f9f34c6--