From patchwork Tue Jun 6 00:51:05 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: 9767763 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 430DC6034B for ; Tue, 6 Jun 2017 00:52:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 38F3E27968 for ; Tue, 6 Jun 2017 00:52:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2DC6028445; Tue, 6 Jun 2017 00:52:53 +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 EA64227968 for ; Tue, 6 Jun 2017 00:52:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751540AbdFFAwe (ORCPT ); Mon, 5 Jun 2017 20:52:34 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:49237 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751495AbdFFAwM (ORCPT ); Mon, 5 Jun 2017 20:52:12 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id e8085293; Tue, 6 Jun 2017 00:51:45 +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=Wx3E csjwLHV0PI0DLBl591GMgPQ=; b=UK6ckHHiSjKMV4QOHaNycZ5vwg31pql9XVLq b0aFpjgVjzEGISrzEVljv9adNu2hlfQSSmwW12+nfy35Zy4bAMIDhhBWZhN76NZZ 2KvA7ZWhNTB0a+XnJ+9EHAEXw+v7YBtdTNBHJLrlNBWTudaIFcaEJs3tn5HDBNwn 5xb5FIgiq17I0vB/FbZp+yZFWSgm7hhFi/950UCz8FgJ+/ySHDb+3SaADwttAQ52 6ea76WYBB8D7lLyc2oaBXuUjfqEJ3A2EmshuC5LpdWvOeNAcfrrHDm5y/Ihulcwy u6+Wlz8zid2GvTrAKjI5P9FYZDwvg0Og9L2orOn0Hs3zSJ3Mmg== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id fef4ce9c (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Tue, 6 Jun 2017 00:51:44 +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 Cc: "Jason A. Donenfeld" Subject: [PATCH v3 10/13] net/neighbor: use get_random_u32 for 32-bit hash random Date: Tue, 6 Jun 2017 02:51:05 +0200 Message-Id: <20170606005108.5646-11-Jason@zx2c4.com> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20170606005108.5646-1-Jason@zx2c4.com> References: <20170606005108.5646-1-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_u32 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. Signed-off-by: Jason A. Donenfeld Cc: David Miller --- net/core/neighbour.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/core/neighbour.c b/net/core/neighbour.c index d274f81fcc2c..9784133b0cdb 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -312,8 +312,7 @@ static struct neighbour *neigh_alloc(struct neigh_table *tbl, struct net_device static void neigh_get_hash_rnd(u32 *x) { - get_random_bytes(x, sizeof(*x)); - *x |= 1; + *x = get_random_u32() | 1; } static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift)