From patchwork Mon Apr 27 15:06:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Wunderlich X-Patchwork-Id: 18094 X-Patchwork-Delegate: sw@simonwunderlich.de Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from diktynna.open-mesh.org (localhost [IPv6:::1]) by diktynna.open-mesh.org (Postfix) with ESMTP id 8745581037; Mon, 27 Apr 2020 17:06:24 +0200 (CEST) ARC-Seal: i=2; cv=fail; a=rsa-sha256; d=open-mesh.org; s=20121; t=1587999973; b=Cqk/kkStxp6jUv2cMrPdvpotIgqbkLnsNRvoO7yinZ+0VM42fk384KsYV0dpMhm5PYYNe dm5QPpUqf8CM6bD8QroWyNjQPYrOTOWq7c8CHcY6i+7kohsQSAgzUSGJ4QkN+gQR2I5n+5S QJ7Ed4afTAanJiJwS4UUw/98VgwaWfk= ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1587999973; h=from : sender : reply-to : subject : date : message-id : to : cc : mime-version : content-type : content-transfer-encoding : content-id : content-description : resent-date : resent-from : resent-sender : resent-to : resent-cc : resent-message-id : in-reply-to : references : list-id : list-help : list-unsubscribe : list-subscribe : list-post : list-owner : list-archive; bh=BoPS+VvBEOmFNvGPUGe2VqfbYQwnNoXfIi/hKC7Iamw=; b=XRKiVZKMOsJ1Y5tMF94MmALFIZTEI/iRplnf56pO2PapVDZJM9RYntGoXW21o4p268qlY PDJWjKYzU9i/67OyBr7fcBe6fR9JeNCXV2zwaU/l0vsdUvHvHj85vsHmcEH+/QtG1RpAFrc Cii+WFbaOMYjB+iWuc3hzO+JGKexx3E= ARC-Authentication-Results: i=2; open-mesh.org; dkim=fail; arc=fail; dmarc=fail header.from=simonwunderlich.de Authentication-Results: open-mesh.org; dkim=fail; arc=fail; dmarc=fail header.from=simonwunderlich.de Received: from simonwunderlich.de (packetmixer.de [IPv6:2001:4d88:2000:24::c0de]) by diktynna.open-mesh.org (Postfix) with ESMTPS id E6EEC80C7D for ; Mon, 27 Apr 2020 17:06:11 +0200 (CEST) Received: from kero.packetmixer.de (p4FD5799A.dip0.t-ipconnect.de [79.213.121.154]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by simonwunderlich.de (Postfix) with ESMTPSA id AE90062071; Mon, 27 Apr 2020 17:06:11 +0200 (CEST) From: Simon Wunderlich To: davem@davemloft.net Subject: [PATCH 4/5] batman-adv: Utilize prandom_u32_max for random [0, max) values Date: Mon, 27 Apr 2020 17:06:06 +0200 Message-Id: <20200427150607.31401-5-sw@simonwunderlich.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200427150607.31401-1-sw@simonwunderlich.de> References: <20200427150607.31401-1-sw@simonwunderlich.de> MIME-Version: 1.0 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1587999971; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mtSkTGMNQ+S4x50rYhfmm89/I8xz+SL6kzJFMaGRlsE=; b=2Qu+WJAqh6Mq70WXhXCFUSxLwUmt3Di1jbpXGUihlvWwd30XWP/9wi+vhHikdbz4BdOHfe 4zJrMXw/9WMQ+CEx1oWuOve5T3fvvSFjmt+JlJwFzR6m4e+tkaLTGWXzj/anrLxw1lm+xI y5byq21bUDwOjOW/3RvSnF/HkP+JJZA= ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1587999971; a=rsa-sha256; cv=none; b=H4WatxhIQbDpckaoVXr528z8nMdI205wH5VPOElX1jBNehZpKN4URppQPDN9QOHJMqFKYC Jc7ZPielLr9DU5iSquUkm3TcDFofJGDVnYnxrkTpQAKAquZCstsVSWuyqdIb1J8peSeHXD MSIygsyQDKmEwDMSRRm6IQR+JdsSNz0= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=none; spf=pass (diktynna.open-mesh.org: domain of sw@simonwunderlich.de designates 2001:4d88:2000:24::c0de as permitted sender) smtp.mailfrom=sw@simonwunderlich.de Message-ID-Hash: SG3Z3CCOMZ4ZX2H4AHZIO4UTG55GZPSR X-Message-ID-Hash: SG3Z3CCOMZ4ZX2H4AHZIO4UTG55GZPSR X-MailFrom: sw@simonwunderlich.de X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-b.a.t.m.a.n.lists.open-mesh.org-0; header-match-b.a.t.m.a.n.lists.open-mesh.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 3.2.1 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: Sven Eckelmann The kernel provides a function to create random values from 0 - (max-1) since commit f337db64af05 ("random32: add prandom_u32_max and convert open coded users"). Simply use this function to replace code sections which use prandom_u32 and a handcrafted method to map it to the correct range. Signed-off-by: Sven Eckelmann --- net/batman-adv/bat_iv_ogm.c | 4 ++-- net/batman-adv/bat_v_elp.c | 2 +- net/batman-adv/bat_v_ogm.c | 4 ++-- 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index a7c8dd7ae513..e87f19c82e8d 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -280,7 +280,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv) unsigned int msecs; msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; - msecs += prandom_u32() % (2 * BATADV_JITTER); + msecs += prandom_u32_max(2 * BATADV_JITTER); return jiffies + msecs_to_jiffies(msecs); } @@ -288,7 +288,7 @@ batadv_iv_ogm_emit_send_time(const struct batadv_priv *bat_priv) /* when do we schedule a ogm packet to be sent */ static unsigned long batadv_iv_ogm_fwd_send_time(void) { - return jiffies + msecs_to_jiffies(prandom_u32() % (BATADV_JITTER / 2)); + return jiffies + msecs_to_jiffies(prandom_u32_max(BATADV_JITTER / 2)); } /* apply hop penalty for a normal link */ diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c index 1e3172db7492..353e49c40e7f 100644 --- a/net/batman-adv/bat_v_elp.c +++ b/net/batman-adv/bat_v_elp.c @@ -49,7 +49,7 @@ static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface) unsigned int msecs; msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER; - msecs += prandom_u32() % (2 * BATADV_JITTER); + msecs += prandom_u32_max(2 * BATADV_JITTER); queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq, msecs_to_jiffies(msecs)); diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 969466218999..0959d32be65c 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -88,7 +88,7 @@ static void batadv_v_ogm_start_queue_timer(struct batadv_hard_iface *hard_iface) unsigned int msecs = BATADV_MAX_AGGREGATION_MS * 1000; /* msecs * [0.9, 1.1] */ - msecs += prandom_u32() % (msecs / 5) - (msecs / 10); + msecs += prandom_u32_max(msecs / 5) - (msecs / 10); queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.aggr_wq, msecs_to_jiffies(msecs / 1000)); } @@ -107,7 +107,7 @@ static void batadv_v_ogm_start_timer(struct batadv_priv *bat_priv) return; msecs = atomic_read(&bat_priv->orig_interval) - BATADV_JITTER; - msecs += prandom_u32() % (2 * BATADV_JITTER); + msecs += prandom_u32_max(2 * BATADV_JITTER); queue_delayed_work(batadv_event_workqueue, &bat_priv->bat_v.ogm_wq, msecs_to_jiffies(msecs)); }