From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932702Ab3APQJS (ORCPT ); Wed, 16 Jan 2013 11:09:18 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:36768 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758663Ab3APQJP (ORCPT ); Wed, 16 Jan 2013 11:09:15 -0500 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Akinobu Mita , Marek Lindner , Simon Wunderlich , Antonio Quartulli , b.a.t.m.a.n@lists.open-mesh.org, "David S. Miller" , netdev@vger.kernel.org, Herton Ronaldo Krzesinski Subject: [PATCH 182/222] batman-adv: fix random jitter calculation Date: Wed, 16 Jan 2013 13:56:22 -0200 Message-Id: <1358351822-7675-183-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1358351822-7675-1-git-send-email-herton.krzesinski@canonical.com> References: <1358351822-7675-1-git-send-email-herton.krzesinski@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Akinobu Mita commit 143cdd8f33909ff5a153e3f02048738c5964ba26 upstream. 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: Herton Ronaldo Krzesinski --- net/batman-adv/bat_iv_ogm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index dc53798..bcf3760 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -117,7 +117,7 @@ static unsigned long bat_iv_ogm_emit_send_time(const struct bat_priv *bat_priv) { return jiffies + msecs_to_jiffies( atomic_read(&bat_priv->orig_interval) - - JITTER + (random32() % 2*JITTER)); + JITTER + (random32() % (2*JITTER))); } /* when do we schedule a ogm packet to be sent */ -- 1.7.9.5