From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1917C3DA7A for ; Mon, 2 Jan 2023 11:47:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232099AbjABLqo (ORCPT ); Mon, 2 Jan 2023 06:46:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232685AbjABLqg (ORCPT ); Mon, 2 Jan 2023 06:46:36 -0500 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:237:300::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D8D9F18 for ; Mon, 2 Jan 2023 03:46:35 -0800 (PST) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1pCJGz-0004rQ-SE; Mon, 02 Jan 2023 12:46:33 +0100 From: Florian Westphal To: Cc: Florian Westphal Subject: [PATCH nf-next 3/3] netfilter: conntrack: avoid reload of ct->status Date: Mon, 2 Jan 2023 12:46:12 +0100 Message-Id: <20230102114612.15860-4-fw@strlen.de> X-Mailer: git-send-email 2.38.2 In-Reply-To: <20230102114612.15860-1-fw@strlen.de> References: <20230102114612.15860-1-fw@strlen.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org Compiler can't merge the two test_bit() calls, so load ct->status once and use non-atomic accesses. This is fine because IPS_EXPECTED or NAT_CLASH are either set at ct creation time or not at all, but compiler can't know that. Signed-off-by: Florian Westphal --- net/netfilter/nf_conntrack_core.c | 9 +++++---- net/netfilter/nf_conntrack_proto_udp.c | 10 ++++++---- 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 17c72d276868..c00858344f02 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1855,14 +1855,15 @@ resolve_normal_ct(struct nf_conn *tmpl, if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) { ctinfo = IP_CT_ESTABLISHED_REPLY; } else { + unsigned long status = READ_ONCE(ct->status); + /* Once we've had two way comms, always ESTABLISHED. */ - if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { + if (likely(status & IPS_SEEN_REPLY)) ctinfo = IP_CT_ESTABLISHED; - } else if (test_bit(IPS_EXPECTED_BIT, &ct->status)) { + else if (status & IPS_EXPECTED) ctinfo = IP_CT_RELATED; - } else { + else ctinfo = IP_CT_NEW; - } } nf_ct_set(skb, ct, ctinfo); return 0; diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c index 3b516cffc779..6b9206635b24 100644 --- a/net/netfilter/nf_conntrack_proto_udp.c +++ b/net/netfilter/nf_conntrack_proto_udp.c @@ -88,6 +88,7 @@ int nf_conntrack_udp_packet(struct nf_conn *ct, const struct nf_hook_state *state) { unsigned int *timeouts; + unsigned long status; if (udp_error(skb, dataoff, state)) return -NF_ACCEPT; @@ -96,26 +97,27 @@ int nf_conntrack_udp_packet(struct nf_conn *ct, if (!timeouts) timeouts = udp_get_timeouts(nf_ct_net(ct)); - if (!nf_ct_is_confirmed(ct)) + status = READ_ONCE(ct->status); + if ((status & IPS_CONFIRMED) == 0) ct->proto.udp.stream_ts = 2 * HZ + jiffies; /* If we've seen traffic both ways, this is some kind of UDP * stream. Set Assured. */ - if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { + if (status & IPS_SEEN_REPLY_BIT) { unsigned long extra = timeouts[UDP_CT_UNREPLIED]; bool stream = false; /* Still active after two seconds? Extend timeout. */ if (time_after(jiffies, ct->proto.udp.stream_ts)) { extra = timeouts[UDP_CT_REPLIED]; - stream = true; + stream = (status & IPS_ASSURED) == 0; } nf_ct_refresh_acct(ct, ctinfo, skb, extra); /* never set ASSURED for IPS_NAT_CLASH, they time out soon */ - if (unlikely((ct->status & IPS_NAT_CLASH))) + if (unlikely((status & IPS_NAT_CLASH))) return NF_ACCEPT; /* Also, more likely to be important, and not a probe */ -- 2.38.2