From patchwork Tue Jun 6 17:48:01 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: 9769403 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 919146035D for ; Tue, 6 Jun 2017 17:49:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8D9F1205AD for ; Tue, 6 Jun 2017 17:49:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8294F205D6; Tue, 6 Jun 2017 17:49:55 +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 4784C205AD for ; Tue, 6 Jun 2017 17:49:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751752AbdFFRtX (ORCPT ); Tue, 6 Jun 2017 13:49:23 -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 S1751615AbdFFRsb (ORCPT ); Tue, 6 Jun 2017 13:48:31 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 2b2715a6; Tue, 6 Jun 2017 17:48:10 +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=xZPxHColhWLnkOpn9xCiHK6PFGUD+KTnrLes IIc8lav4U3DmwiAn8Z8eTWFgrU5bZzasQlkz+2OpYXXUCtu35OClz8zPVfYzhyLH 2HAi+EmaY1pQjwuEZSdSYQv4LPkNuw4EWzZyLhfxrkeN/eo4iz+THJSu/K1F7yk3 IG5cTe9rCh45oXoMjW1lPgyw0qxR/iL8XGbJZftQrbjaHNkA/VNsZtiQPQMaWG/c ej8YUYqXell5VvGNVqtMaxO6lXR1ucOmpdt/YhlrD+AFku03bK36hZRVIVswM8yT 0NsdNPPX0lgv2fnTnJnsmETZgVdnluMRI5exAn9/p64ucGVdug== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 75e24749 (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Tue, 6 Jun 2017 17:48:09 +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 10/13] net/neighbor: use get_random_u32 for 32-bit hash random Date: Tue, 6 Jun 2017 19:48:01 +0200 Message-Id: <20170606174804.31124-11-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_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)