[SRU][F:linux-bluefield][PATCH v2 4/5] netfilter: conntrack: Introduce udp offload timeout configuration

[Bodong Wang]

From: Oz Shlomo <ozsh at nvidia.com>

BugLink: https://launchpad.net/bugs/1934401

UDP connections may be offloaded from nf conntrack to nf flow table.
Offloaded connections are aged after 30 seconds of inactivity.
Once aged, ownership is returned to conntrack with a hard coded pickup
time of 30 seconds, after which the connection may be deleted.
eted. The current aging intervals may be too aggressive for some users.

Provide users with the ability to control the nf flow table offload
aging and pickup time intervals via sysctl parameter as a pre-step for
configuring the nf flow table GC timeout intervals.

Signed-off-by: Oz Shlomo <ozsh at nvidia.com>
Reviewed-by: Paul Blakey <paulb at nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo at netfilter.org>
(cherry picked from commit 975c57504da1114551fdb3a91ed61dda7739613e linux-next)
Signed-off-by: Bodong Wang <bodong at nvidia.com>
---
 include/net/netns/conntrack.h           |  4 ++++
 net/netfilter/nf_conntrack_proto_udp.c  |  5 +++++
 net/netfilter/nf_conntrack_standalone.c | 22 ++++++++++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/include/net/netns/conntrack.h b/include/net/netns/conntrack.h
index 11be37c..67bbaa6 100644
--- a/include/net/netns/conntrack.h
+++ b/include/net/netns/conntrack.h
@@ -41,6 +41,10 @@ enum udp_conntrack {
 
 struct nf_udp_net {
 	unsigned int timeouts[UDP_CT_MAX];
+#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
+	unsigned int offload_timeout;
+	unsigned int offload_pickup;
+#endif
 };
 
 struct nf_icmp_net {
diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c
index 760ca24..5c1b9bc 100644
--- a/net/netfilter/nf_conntrack_proto_udp.c
+++ b/net/netfilter/nf_conntrack_proto_udp.c
@@ -276,6 +276,11 @@ void nf_conntrack_udp_init_net(struct net *net)
 
 	for (i = 0; i < UDP_CT_MAX; i++)
 		un->timeouts[i] = udp_timeouts[i];
+
+#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
+	un->offload_timeout = 30 * HZ;
+	un->offload_pickup = 30 * HZ;
+#endif
 }
 
 const struct nf_conntrack_l4proto nf_conntrack_l4proto_udp =
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 3f4b449..ac8f12b 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -576,6 +576,10 @@ enum nf_ct_sysctl_index {
 	NF_SYSCTL_CT_PROTO_TCP_MAX_RETRANS,
 	NF_SYSCTL_CT_PROTO_TIMEOUT_UDP,
 	NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_STREAM,
+#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
+	NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD,
+	NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD_PICKUP,
+#endif
 	NF_SYSCTL_CT_PROTO_TIMEOUT_ICMP,
 	NF_SYSCTL_CT_PROTO_TIMEOUT_ICMPV6,
 #ifdef CONFIG_NF_CT_PROTO_SCTP
@@ -810,6 +814,20 @@ enum nf_ct_sysctl_index {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_jiffies,
 	},
+#if IS_ENABLED(CONFIG_NFT_FLOW_OFFLOAD)
+	[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD] = {
+		.procname	= "nf_flowtable_udp_timeout",
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD_PICKUP] = {
+		.procname	= "nf_flowtable_udp_pickup",
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+#endif
 	[NF_SYSCTL_CT_PROTO_TIMEOUT_ICMP] = {
 		.procname	= "nf_conntrack_icmp_timeout",
 		.maxlen		= sizeof(unsigned int),
@@ -1078,6 +1096,10 @@ static int nf_conntrack_standalone_init_sysctl(struct net *net)
 	table[NF_SYSCTL_CT_PROTO_TIMEOUT_ICMPV6].data = &nf_icmpv6_pernet(net)->timeout;
 	table[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP].data = &un->timeouts[UDP_CT_UNREPLIED];
 	table[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_STREAM].data = &un->timeouts[UDP_CT_REPLIED];
+#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
+	table[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD].data = &un->offload_timeout;
+	table[NF_SYSCTL_CT_PROTO_TIMEOUT_UDP_OFFLOAD_PICKUP].data = &un->offload_pickup;
+#endif
 
 	nf_conntrack_standalone_init_tcp_sysctl(net, table);
 	nf_conntrack_standalone_init_sctp_sysctl(net, table);
-- 
1.8.3.1