From patchwork Tue Jun 6 17:48:02 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: 9769389 X-Patchwork-Delegate: herbert@gondor.apana.org.au 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 3510060393 for ; Tue, 6 Jun 2017 17:49:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3077E2849E for ; Tue, 6 Jun 2017 17:49:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1E097284E3; Tue, 6 Jun 2017 17:49:16 +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=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A809E284DA for ; Tue, 6 Jun 2017 17:49:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751646AbdFFRse (ORCPT ); Tue, 6 Jun 2017 13:48:34 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:38383 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751591AbdFFRsd (ORCPT ); Tue, 6 Jun 2017 13:48:33 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id ae069eec; Tue, 6 Jun 2017 17:48:12 +0000 (UTC) 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=1yJL ns3WB1X559vpcGA+HBeZM+0=; b=BdGSGTXbiqGwXZa6JBjgOIgzhGeCDjeFaZ+V fjhkKjJefLSxH6h7sCvw99uPn71jF9qx8irojS80QTu6vBsskPMcFT2c6iGTcYds 9iLO729PcRTWJhfEXvTGzlFzfkXzNH5FbFPIsY34+QiWz/w5SRu34tFzcKN6x2xt O1Gqoidh0PYQifASnOh4eRGpgnrdtFQaCGyLOwV/oPeU5OPTOTKUWKH6FcoOhlGF c8A0ACIkwzrQJAVVz6cpyt962LMC/r/e3osVwA98fZzldg+hucd9L3dpsS4fhztO LSa2G05+ED79wfGBcB/MrU8yXRVI9F/aKUh+ppLJ2FZtHMoHYQ== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 2a27d802 (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Tue, 6 Jun 2017 17:48:11 +0000 (UTC) From: "Jason A. Donenfeld" To: Theodore Ts'o , Linux Crypto Mailing List , LKML , kernel-hardening@lists.openwall.com, Greg Kroah-Hartman , David Miller , Eric Biggers Cc: "Jason A. Donenfeld" Subject: [PATCH v4 11/13] net/route: use get_random_int for random counter Date: Tue, 6 Jun 2017 19:48:02 +0200 Message-Id: <20170606174804.31124-12-Jason@zx2c4.com> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20170606174804.31124-1-Jason@zx2c4.com> References: <20170606174804.31124-1-Jason@zx2c4.com> Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org 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 655d9eebe43e..11e001a42094 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2936,8 +2936,7 @@ 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; }