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=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8C9FBC433E2 for ; Tue, 1 Sep 2020 13:14:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60D6B206EF for ; Tue, 1 Sep 2020 13:14:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728130AbgIANNp convert rfc822-to-8bit (ORCPT ); Tue, 1 Sep 2020 09:13:45 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([207.82.80.151]:49264 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728048AbgIANK3 (ORCPT ); Tue, 1 Sep 2020 09:10:29 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-124-RgJ3VotCP16CESXx20TH0w-1; Tue, 01 Sep 2020 14:10:19 +0100 X-MC-Unique: RgJ3VotCP16CESXx20TH0w-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Tue, 1 Sep 2020 14:10:18 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Tue, 1 Sep 2020 14:10:18 +0100 From: David Laight To: 'Willy Tarreau' , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" CC: Sedat Dilek , George Spelvin , "Amit Klein" , Eric Dumazet , "Jason A. Donenfeld" , Andy Lutomirski , Kees Cook , Thomas Gleixner , Peter Zijlstra , Linus Torvalds , "tytso@mit.edu" , Florian Westphal , Marc Plumb Subject: RE: [PATCH 1/2] random32: make prandom_u32() output unpredictable Thread-Topic: [PATCH 1/2] random32: make prandom_u32() output unpredictable Thread-Index: AQHWgCtYkxpri6yNnUCyYLzB8IqNYqlTwT5w Date: Tue, 1 Sep 2020 13:10:18 +0000 Message-ID: References: <20200901064302.849-1-w@1wt.eu> <20200901064302.849-2-w@1wt.eu> In-Reply-To: <20200901064302.849-2-w@1wt.eu> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Willy Tarreau > Sent: 01 September 2020 07:43 ... > +/* > + * Generate some initially weak seeding values to allow > + * the prandom_u32() engine to be started. > + */ > +static int __init prandom_init_early(void) > +{ > + int i; > + unsigned long v0, v1, v2, v3; > + > + if (!arch_get_random_long(&v0)) > + v0 = jiffies; Isn't jiffies likely to be zero here? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)