From patchwork Wed Jun 7 23:26:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 9773283 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D0C3360234 for ; Wed, 7 Jun 2017 23:27:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C4395283AD for ; Wed, 7 Jun 2017 23:27:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B6F702848D; Wed, 7 Jun 2017 23:27:34 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 4C391283AD for ; Wed, 7 Jun 2017 23:27:33 +0000 (UTC) Received: (qmail 30115 invoked by uid 550); 7 Jun 2017 23:26:53 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 26415 invoked from network); 7 Jun 2017 23:26:36 -0000 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=zx2c4.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=mail; bh=JaFl dA2KJnLPzHIExR5XqUmgB7U=; b=U8D453bI+K/R5BIHJ9XOHkEGzTKulOv4Z3kE H8sqhNpj4zk4PPZnCxBWRbYBnB36qPI8XYpgH3tgqV6Ez4/O2SkuNYvM80bVSuv9 I5weQKd0TQPPRu5vI9cs5DAQ7+6F4uHGh8gQut/X5WfmAqf11CoTW50hUr4H4jHI KN+VaoeC7X1QoLGGML3D3n9acQQo/w++Y8cRd149JUOihR9LVsB3TYEdhu8StKPX 9Y4MaEV+mDpJhszoLz7eXI8lUG2FOI7kfPbiFYpaEw2FoNRKumdS8LQLWeRJT1YM VxNJAd4Ncveduew+m1t/PQge+7MSKpAjU4CRmzhd+G9yqG5u1g== From: "Jason A. Donenfeld" To: Theodore Ts'o , Linux Crypto Mailing List , LKML , kernel-hardening@lists.openwall.com, Greg Kroah-Hartman , Eric Biggers , Linus Torvalds , David Miller Cc: "Jason A. Donenfeld" Date: Thu, 8 Jun 2017 01:26:05 +0200 Message-Id: <20170607232607.26870-12-Jason@zx2c4.com> In-Reply-To: <20170607232607.26870-1-Jason@zx2c4.com> References: <20170607232607.26870-1-Jason@zx2c4.com> Subject: [kernel-hardening] [PATCH v5 11/13] net/route: use get_random_int for random counter X-Virus-Scanned: ClamAV using ClamSMTP Using get_random_int here is faster, more fitting of the use case, and just as cryptographically secure. It also has the benefit of providing better randomness at early boot, which is when many of these structures are assigned. Also, semantically, it's not really proper to have been assigning an atomic_t in this way before, even if in practice it works fine. Signed-off-by: Jason A. Donenfeld Cc: David Miller --- net/ipv4/route.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 6883b3d4ba8f..32a3332ec9cf 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2944,8 +2944,7 @@ static __net_init int rt_genid_init(struct net *net) { atomic_set(&net->ipv4.rt_genid, 0); atomic_set(&net->fnhe_genid, 0); - get_random_bytes(&net->ipv4.dev_addr_genid, - sizeof(net->ipv4.dev_addr_genid)); + atomic_set(&net->ipv4.dev_addr_genid, get_random_int()); return 0; }