ipv4: Namespaceify tcp_fin_timeout sysctl knob

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netns/ipv4.h

@@ -105,6 +105,7 @@ struct netns_ipv4 {
 	int sysctl_tcp_retries1;
 	int sysctl_tcp_retries2;
 	int sysctl_tcp_orphan_retries;
+	int sysctl_tcp_fin_timeout;
 
 	struct ping_group_range ping_group_range;
 

include/net/tcp.h

@@ -239,7 +239,6 @@ extern struct inet_timewait_death_row tcp_death_row;
 extern int sysctl_tcp_timestamps;
 extern int sysctl_tcp_window_scaling;
 extern int sysctl_tcp_sack;
-extern int sysctl_tcp_fin_timeout;
 extern int sysctl_tcp_fastopen;
 extern int sysctl_tcp_retrans_collapse;
 extern int sysctl_tcp_stdurg;
@@ -1249,7 +1248,7 @@ static inline u32 keepalive_time_elapsed(const struct tcp_sock *tp)
 
 static inline int tcp_fin_time(const struct sock *sk)
 {
-	int fin_timeout = tcp_sk(sk)->linger2 ? : sysctl_tcp_fin_timeout;
+	int fin_timeout = tcp_sk(sk)->linger2 ? : sock_net(sk)->ipv4.sysctl_tcp_fin_timeout;
 	const int rto = inet_csk(sk)->icsk_rto;
 
 	if (fin_timeout < (rto << 2) - (rto >> 1))

net/ipv4/sysctl_net_ipv4.c

@@ -319,13 +319,6 @@ static struct ctl_table ipv4_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
-	{
-		.procname	= "tcp_fin_timeout",
-		.data		= &sysctl_tcp_fin_timeout,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
 	{
 		.procname	= "tcp_fastopen",
 		.data		= &sysctl_tcp_fastopen,
@@ -960,6 +953,13 @@ static struct ctl_table ipv4_net_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
+	{
+		.procname	= "tcp_fin_timeout",
+		.data		= &init_net.ipv4.sysctl_tcp_fin_timeout,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
 	{ }
 };
 

net/ipv4/tcp.c

@@ -282,8 +282,6 @@
 #include <asm/unaligned.h>
 #include <net/busy_poll.h>
 
-int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
-
 int sysctl_tcp_min_tso_segs __read_mostly = 2;
 
 int sysctl_tcp_autocorking __read_mostly = 1;
@@ -2330,6 +2328,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct inet_connection_sock *icsk = inet_csk(sk);
+	struct net *net = sock_net(sk);
 	int val;
 	int err = 0;
 
@@ -2526,7 +2525,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level,
 	case TCP_LINGER2:
 		if (val < 0)
 			tp->linger2 = -1;
-		else if (val > sysctl_tcp_fin_timeout / HZ)
+		else if (val > net->ipv4.sysctl_tcp_fin_timeout / HZ)
 			tp->linger2 = 0;
 		else
 			tp->linger2 = val * HZ;
@@ -2771,7 +2770,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
 	case TCP_LINGER2:
 		val = tp->linger2;
 		if (val >= 0)
-			val = (val ? : sysctl_tcp_fin_timeout) / HZ;
+			val = (val ? : net->ipv4.sysctl_tcp_fin_timeout) / HZ;
 		break;
 	case TCP_DEFER_ACCEPT:
 		val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept,

net/ipv4/tcp_ipv4.c

@@ -2394,6 +2394,7 @@ static int __net_init tcp_sk_init(struct net *net)
 	net->ipv4.sysctl_tcp_retries1 = TCP_RETR1;
 	net->ipv4.sysctl_tcp_retries2 = TCP_RETR2;
 	net->ipv4.sysctl_tcp_orphan_retries = 0;
+	net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT;
 
 	return 0;
 fail: