From patchwork Wed Jan 9 20:35:23 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 210873 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 7FA7D2C00D8 for ; Thu, 10 Jan 2013 08:02:37 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933858Ab3AIVCd (ORCPT ); Wed, 9 Jan 2013 16:02:33 -0500 Received: from mail.kernel.org ([198.145.19.201]:43355 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933838Ab3AIUkZ (ORCPT ); Wed, 9 Jan 2013 15:40:25 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C15F420424; Wed, 9 Jan 2013 20:40:24 +0000 (UTC) Received: from localhost (c-67-168-183-230.hsd1.wa.comcast.net [67.168.183.230]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0ACEB20426; Wed, 9 Jan 2013 20:40:24 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Akinobu Mita , Antonio Quartulli , Marek Lindner , Simon Wunderlich , "David S. Miller" , b.a.t.m.a.n@lists.open-mesh.org, netdev@vger.kernel.org Subject: [ 084/123] batman-adv: fix random jitter calculation Date: Wed, 9 Jan 2013 12:35:23 -0800 Message-Id: <20130109201509.395329312@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130109201458.392601412@linuxfoundation.org> References: <20130109201458.392601412@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 X-Spam-Status: No, score=1.0 required=5.0 tests=BAYES_00,KHOP_BIG_TO_CC, UNPARSEABLE_RELAY autolearn=no version=3.3.1 X-Spam-Level: * X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Akinobu Mita [ Upstream commit 143cdd8f33909ff5a153e3f02048738c5964ba26 ] batadv_iv_ogm_emit_send_time() attempts to calculates a random integer in the range of 'orig_interval +- BATADV_JITTER' by the below lines. msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; msecs += (random32() % 2 * BATADV_JITTER); But it actually gets 'orig_interval' or 'orig_interval - BATADV_JITTER' because '%' and '*' have same precedence and associativity is left-to-right. This adds the parentheses at the appropriate position so that it matches original intension. Signed-off-by: Akinobu Mita Acked-by: Antonio Quartulli Cc: Marek Lindner Cc: Simon Wunderlich Cc: Antonio Quartulli Cc: b.a.t.m.a.n@lists.open-mesh.org Cc: "David S. Miller" Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/bat_iv_ogm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -119,7 +119,7 @@ batadv_iv_ogm_emit_send_time(const struc unsigned int msecs; msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; - msecs += (random32() % 2 * BATADV_JITTER); + msecs += random32() % (2 * BATADV_JITTER); return jiffies + msecs_to_jiffies(msecs); }