From patchwork Wed Jan 8 19:13:22 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 308403 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 8D5512C00B8 for ; Thu, 9 Jan 2014 06:13:49 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756850AbaAHTNp (ORCPT ); Wed, 8 Jan 2014 14:13:45 -0500 Received: from mail.us.es ([193.147.175.20]:54773 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756115AbaAHTNn (ORCPT ); Wed, 8 Jan 2014 14:13:43 -0500 Received: (qmail 14545 invoked from network); 8 Jan 2014 20:13:41 +0100 Received: from unknown (HELO us.es) (192.168.2.12) by us.es with SMTP; 8 Jan 2014 20:13:41 +0100 Received: (qmail 27389 invoked by uid 507); 8 Jan 2014 19:13:41 -0000 X-Qmail-Scanner-Diagnostics: from 127.0.0.1 by antivirus2 (envelope-from , uid 501) with qmail-scanner-2.10 (clamdscan: 0.98/18327. spamassassin: 3.3.2. 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Processed in 4.435359 secs); 08 Jan 2014 19:13:41 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on antivirus2 X-Spam-Level: X-Spam-Status: No, score=-102.2 required=7.5 tests=ALL_TRUSTED,BAYES_50, SMTPAUTH_US,USER_IN_WHITELIST autolearn=disabled version=3.3.2 X-Spam-ASN: X-Envelope-From: pablo@netfilter.org Received: from unknown (HELO antivirus2) (127.0.0.1) by us.es with SMTP; 8 Jan 2014 19:13:37 -0000 Received: from 192.168.1.13 (192.168.1.13) by antivirus2 (F-Secure/fsigk_smtp/412/antivirus2); Wed, 08 Jan 2014 20:13:37 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/412/antivirus2) Received: (qmail 8034 invoked from network); 8 Jan 2014 20:13:37 +0100 Received: from unknown (HELO soleta.us.es) (pneira@us.es@10.100.3.147) by mail.us.es with SMTP; 8 Jan 2014 20:13:37 +0100 From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 1/3] Revert "netfilter: avoid get_random_bytes calls" Date: Wed, 8 Jan 2014 20:13:22 +0100 Message-Id: <1389208404-3956-2-git-send-email-pablo@netfilter.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1389208404-3956-1-git-send-email-pablo@netfilter.org> References: <1389208404-3956-1-git-send-email-pablo@netfilter.org> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This reverts commit a42b99a6e329654d376b330de057eff87686d890. Hannes Frederic Sowa reported some problems with this patch, more specifically that prandom_u32() may not be ready at boot time, see: http://marc.info/?l=linux-netdev&m=138896532403533&w=2 Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink_log.c | 8 ++++++++ net/netfilter/nft_hash.c | 2 +- net/netfilter/xt_RATEEST.c | 2 +- net/netfilter/xt_connlimit.c | 2 +- net/netfilter/xt_hashlimit.c | 2 +- net/netfilter/xt_recent.c | 2 +- 6 files changed, 13 insertions(+), 5 deletions(-) diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index 7d4254b..3c4b69e 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -28,6 +28,8 @@ #include #include #include +#include +#include #include #include #include @@ -73,6 +75,7 @@ struct nfulnl_instance { }; #define INSTANCE_BUCKETS 16 +static unsigned int hash_init; static int nfnl_log_net_id __read_mostly; @@ -1063,6 +1066,11 @@ static int __init nfnetlink_log_init(void) { int status = -ENOMEM; + /* it's not really all that important to have a random value, so + * we can do this from the init function, even if there hasn't + * been that much entropy yet */ + get_random_bytes(&hash_init, sizeof(hash_init)); + netlink_register_notifier(&nfulnl_rtnl_notifier); status = nfnetlink_subsys_register(&nfulnl_subsys); if (status < 0) { diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c index 6aae699..3d3f8fc 100644 --- a/net/netfilter/nft_hash.c +++ b/net/netfilter/nft_hash.c @@ -164,7 +164,7 @@ static int nft_hash_init(const struct nft_set *set, unsigned int cnt, i; if (unlikely(!nft_hash_rnd_initted)) { - nft_hash_rnd = prandom_u32(); + get_random_bytes(&nft_hash_rnd, 4); nft_hash_rnd_initted = true; } diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c index 190854b..370adf6 100644 --- a/net/netfilter/xt_RATEEST.c +++ b/net/netfilter/xt_RATEEST.c @@ -100,7 +100,7 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par) int ret; if (unlikely(!rnd_inited)) { - jhash_rnd = prandom_u32(); + get_random_bytes(&jhash_rnd, sizeof(jhash_rnd)); rnd_inited = true; } diff --git a/net/netfilter/xt_connlimit.c b/net/netfilter/xt_connlimit.c index 7671e82..c40b269 100644 --- a/net/netfilter/xt_connlimit.c +++ b/net/netfilter/xt_connlimit.c @@ -229,7 +229,7 @@ static int connlimit_mt_check(const struct xt_mtchk_param *par) u_int32_t rand; do { - rand = prandom_u32(); + get_random_bytes(&rand, sizeof(rand)); } while (!rand); cmpxchg(&connlimit_rnd, 0, rand); } diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c index d819f62..a3910fc 100644 --- a/net/netfilter/xt_hashlimit.c +++ b/net/netfilter/xt_hashlimit.c @@ -177,7 +177,7 @@ dsthash_alloc_init(struct xt_hashlimit_htable *ht, /* initialize hash with random val at the time we allocate * the first hashtable entry */ if (unlikely(!ht->rnd_initialized)) { - ht->rnd = prandom_u32(); + get_random_bytes(&ht->rnd, sizeof(ht->rnd)); ht->rnd_initialized = true; } diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index bfdc29f..1e657cf 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -334,7 +334,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par, size_t sz; if (unlikely(!hash_rnd_inited)) { - hash_rnd = prandom_u32(); + get_random_bytes(&hash_rnd, sizeof(hash_rnd)); hash_rnd_inited = true; } if (info->check_set & ~XT_RECENT_VALID_FLAGS) {