220 40353 article Path: news.gmane.org!.POSTED!not-for-mail From: Daniel Gutson Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Re: more security concerns Date: Sun, 7 Oct 2018 01:54:23 -0300 Lines: 154 Approved: news@gmane.org Message-ID: References: <8fa2ebcf-19c5-4b32-a8c6-9fa503010467@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="00000000000037717905779c4dfa" X-Trace: blaine.gmane.org 1538887954 10014 195.159.176.226 (7 Oct 2018 04:52:34 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 7 Oct 2018 04:52:34 +0000 (UTC) To: std-proposals Original-X-From: std-proposals+bncBDE3NBMV6UFBBEFD43OQKGQETNHWLEI@isocpp.org Sun Oct 07 06:52:30 2018 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-lj1-f198.google.com ([209.85.208.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1g913O-0002VR-MY for gclcip-std-proposals@m.gmane.org; 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[209.85.220.41]) by mx.google.com with SMTPS id z9-v6sor764010ljz.29.2018.10.06.21.54.39 for (Google Transport Security); Sat, 06 Oct 2018 21:54:39 -0700 (PDT) Received-SPF: pass (google.com: domain of danielgutson@gmail.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; X-Received: by 2002:a2e:8ec6:: with SMTP id e6-v6mr9784584ljl.166.1538888077634; Sat, 06 Oct 2018 21:54:37 -0700 (PDT) In-Reply-To: <8fa2ebcf-19c5-4b32-a8c6-9fa503010467@isocpp.org> X-Original-Sender: danielgutson@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=GZYL2dko; spf=pass (google.com: domain of danielgutson@gmail.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=danielgutson@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Spam-Checked-In-Group: std-proposals@isocpp.org X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:40353 Archived-At: --00000000000037717905779c4dfa Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable El lun., 1 de oct. de 2018 a la(s) 06:28, escribi=C3=B3: > > > Op vrijdag 28 september 2018 13:14:06 UTC+2 schreef Daniel Gutson: >> >> Again, on the DSE related optimizations. >> >> I'm at the Ekoparty where I will show a presentation about security >> vulnerabilities caused by compiler optimizations. The subject is more an= d >> more serious (e.g. [1]). >> >> I want to propose to allow [[nodiscard]] in individual expressions, such >> as calls to memset(), std::fill_n, and assignments (DSE happens with bot= h >> memory and registers). >> >> What's DSE? > And what's [1]? > Sorry for the lack of context, I strongly suggest people to take a look at these papers without further participating in this discussion: https://www.usenix.org/system/files/conference/usenixsecurity17/sec17-yang.= pdf https://nebelwelt.net/publications/files/15LangSec.pdf Comments: https://wiki.sei.cmu.edu/confluence/display/c/MSC06-C.+Beware+of+compiler+o= ptimizations There are plenty of issues filed to the gcc and clang issue trackers about this that were systematically closed as invalid. But the problem remains and is deadly serious. I did a demonstration at the Ekoparty of an exploit using this. > > > -- > You received this message because you are subscribed to the Google Groups > "ISO C++ Standard - Future Proposals" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to std-proposals+unsubscribe@isocpp.org. > To post to this group, send email to std-proposals@isocpp.org. > To view this discussion on the web visit > https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/8fa2ebcf-19c= 5-4b32-a8c6-9fa503010467%40isocpp.org > > . > --=20 Who=E2=80=99s got the sweetest disposition? One guess, that=E2=80=99s who? Who=E2=80=99d never, ever start an argument? Who never shows a bit of temperament? Who's never wrong but always right? Who'd never dream of starting a fight? Who get stuck with all the bad luck? --=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/CAFdMc-3ow7TvHO%2B2Y9Ww12PwGRj6H5hq3aennxt2Jq7-X= GLzmw%40mail.gmail.com. --00000000000037717905779c4dfa Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable

El lun., 1 de oct. de 2018 a l= a(s) 06:28, <olaf@join.cc> escribi=C3=B3:


Op vrijdag 28 sep= tember 2018 13:14:06 UTC+2 schreef Daniel Gutson:
Again, on the DSE related optimiza= tions.

I'm at the Ekoparty where I will show a prese= ntation about security vulnerabilities caused by compiler optimizations. Th= e subject is more and more serious (e.g. [1]).

I w= ant to propose to allow [[nodiscard]] in individual expressions, such as ca= lls to memset(), std::fill_n, and assignments (DSE happens with both memory= and registers).

What's DSE= ?
And what's [1]?

Sorry for the lack of context, I strongly suggest people to take a look at= these papers without further participating in this discussion:=C2=A0
=

There are plenty of issues filed to= the gcc and clang issue trackers about this that were systematically close= d as invalid. But the problem remains and is deadly serious. I did a demons= tration at the Ekoparty of an exploit using this.
=C2=A0
=C2=A0=

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To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org.
To post to this group, send email to std-proposals@isocpp.org.
To view this discussion on the web visit = https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/8fa2ebcf-19c5-= 4b32-a8c6-9fa503010467%40isocpp.org.


--
Who=E2=80=99s got the sweetest disposition?
O= ne guess, that=E2=80=99s who?
Who=E2=80=99d never, ever start an argumen= t?
Who never shows a bit of temperament?
Who's never wrong but al= ways right?
Who'd never dream of starting a fight?
Who get stuck = with all the bad luck?

--
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To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+unsubscribe@isocpp.org.
To post to this group, send email to std-proposals@isocpp.org.
To view this discussion on the web visit h= ttps://groups.google.com/a/isocpp.org/d/msgid/std-proposals/CAFdMc-3ow7TvHO= %2B2Y9Ww12PwGRj6H5hq3aennxt2Jq7-XGLzmw%40mail.gmail.com.
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