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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 E0147C49ED7 for ; Tue, 17 Sep 2019 02:07:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A73F520665 for ; Tue, 17 Sep 2019 02:07:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=codon.org.uk header.i=@codon.org.uk header.b="xHErRN1q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391960AbfIQCHP (ORCPT ); Mon, 16 Sep 2019 22:07:15 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:48057 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728556AbfIQCHP (ORCPT ); Mon, 16 Sep 2019 22:07:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=codon.org.uk; s=63138784; h=Subject:Message-ID:From:CC:To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To: Date:Sender:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=vVkn2O/9lGVNrbPzlDo6XOPFmZ8O6RHYGV95uzIF1K4=; b=xHErRN1qIc/xI/5awjhwSFsV39 Jd9w5VmsEBkVcocyN4+byYKC0GvQw6HOLfxqIGFvGkmhMLkHpkK7APEYxO1WvsGH0CUhzKlGGbygr RAUxRzG0L+yl27dmbBDl2HOHvXNGY76txjx0WFC6l+aRu4i59Oek1fIlAqQE5MpUQLhE=; Received: from 199-83-223-235.public.monkeybrains.net ([199.83.223.235] helo=[192.168.1.141]) by cavan.codon.org.uk with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.89) (envelope-from ) id 1iA2tG-000305-SF; Tue, 17 Sep 2019 03:06:53 +0100 Date: Mon, 16 Sep 2019 18:46:07 -0700 User-Agent: K-9 Mail for Android In-Reply-To: References: <20190916042952.GB23719@1wt.eu> <20190916061252.GA24002@1wt.eu> <20190916172117.GB15263@mit.edu> <20190916230217.vmgvsm6o2o4uq5j7@srcf.ucam.org> <20190916231103.bic65ab4ifv7vhio@srcf.ucam.org> <20190916232922.GA7880@darwi-home-pc> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable To: Linus Torvalds CC: "Ahmed S. Darwish" , "Theodore Y. Ts'o" , Willy Tarreau , Vito Caputo , Lennart Poettering , Andreas Dilger , Jan Kara , Ray Strode , William Jon McCann , "Alexander E. Patrakov" , zhangjs , linux-ext4@vger.kernel.org, lkml From: Matthew Garrett Message-ID: X-SA-Do-Not-Run: Yes X-SA-Exim-Connect-IP: 199.83.223.235 X-SA-Exim-Mail-From: mjg59@srcf.ucam.org Subject: Re: Linux 5.3-rc8 X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: No (on cavan.codon.org.uk); Unknown failure Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16 September 2019 18:41:36 GMT-07:00, Linus Torvalds wrote: >On Mon, Sep 16, 2019 at 6:24 PM Matthew Garrett >wrote: >> >> Exactly the scenario where you want getrandom() to block, yes=2E > >It *would* block=2E Just not forever=2E It's already not forever - there's enough running in the background of tha= t system that it'll unblock eventually=2E=20 >And btw, the whole "generate key at boot when nothing else is going >on" is already broken, so presumably nobody actually does it=2E If nothing ever did this, why was getrandom() designed in a way to protect= against this situation?=20 >See why I'm saying "hypothetical"? You're doing it again=2E > >> >Then you have to ignore the big warning too=2E >> >> The big warning that's only printed in dmesg? > >Well, the patch actually made getrandom() return en error too, but you >seem more interested in the hypotheticals than in arguing actualities=2E If you want to be safe, terminate the process=2E --=20 Matthew Garrett | mjg59@srcf=2Eucam=2Eorg