From: Florian Westphal Date: Mon, 2 Jan 2023 11:46:12 +0000 (+0100) Subject: netfilter: conntrack: avoid reload of ct->status X-Git-Tag: v6.6.17~5509^2~264^2~6 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4883ec512c1715fc827557f0e2bfce76c6530757;p=platform%2Fkernel%2Flinux-rpi.git netfilter: conntrack: avoid reload of ct->status 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 --- diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 81ece11..9e12cad 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1854,14 +1854,15 @@ 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 3b516cf..6b92066 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 */