Merge branch 'tcp-Namespaceify-3-sysctls'

Eric Dumazet says:

====================
tcp: Namespaceify 3 sysctls

Move tcp_sack, tcp_window_scaling and tcp_timestamps
sysctls to network namespaces.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 75 insertions, 64 deletions

diff --git a/net/core/secure_seq.c b/net/core/secure_seq.c
index ae35cce3a40d..7232274de334 100644
--- a/net/core/secure_seq.c
+++ b/net/core/secure_seq.c
@@ -51,7 +51,8 @@ static u32 seq_scale(u32 seq)
 #endif
 
 #if IS_ENABLED(CONFIG_IPV6)
-u32 secure_tcpv6_ts_off(const __be32 *saddr, const __be32 *daddr)
+u32 secure_tcpv6_ts_off(const struct net *net,
+			const __be32 *saddr, const __be32 *daddr)
 {
 	const struct {
 		struct in6_addr saddr;
@@ -61,7 +62,7 @@ u32 secure_tcpv6_ts_off(const __be32 *saddr, const __be32 *daddr)
 		.daddr = *(struct in6_addr *)daddr,
 	};
 
-	if (sysctl_tcp_timestamps != 1)
+	if (net->ipv4.sysctl_tcp_timestamps != 1)
 		return 0;
 
 	ts_secret_init();
@@ -113,9 +114,9 @@ EXPORT_SYMBOL(secure_ipv6_port_ephemeral);
 #endif
 
 #ifdef CONFIG_INET
-u32 secure_tcp_ts_off(__be32 saddr, __be32 daddr)
+u32 secure_tcp_ts_off(const struct net *net, __be32 saddr, __be32 daddr)
 {
-	if (sysctl_tcp_timestamps != 1)
+	if (net->ipv4.sysctl_tcp_timestamps != 1)
 		return 0;
 
 	ts_secret_init();
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 6426250a58ea..7835bb4a1fab 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -232,7 +232,8 @@ EXPORT_SYMBOL(tcp_get_cookie_sock);
  * return false if we decode a tcp option that is disabled
  * on the host.
  */
-bool cookie_timestamp_decode(struct tcp_options_received *tcp_opt)
+bool cookie_timestamp_decode(const struct net *net,
+			     struct tcp_options_received *tcp_opt)
 {
 	/* echoed timestamp, lowest bits contain options */
 	u32 options = tcp_opt->rcv_tsecr;
@@ -242,12 +243,12 @@ bool cookie_timestamp_decode(struct tcp_options_received *tcp_opt)
 		return true;
 	}
 
-	if (!sysctl_tcp_timestamps)
+	if (!net->ipv4.sysctl_tcp_timestamps)
 		return false;
 
 	tcp_opt->sack_ok = (options & TS_OPT_SACK) ? TCP_SACK_SEEN : 0;
 
-	if (tcp_opt->sack_ok && !sysctl_tcp_sack)
+	if (tcp_opt->sack_ok && !net->ipv4.sysctl_tcp_sack)
 		return false;
 
 	if ((options & TS_OPT_WSCALE_MASK) == TS_OPT_WSCALE_MASK)
@@ -256,7 +257,7 @@ bool cookie_timestamp_decode(struct tcp_options_received *tcp_opt)
 	tcp_opt->wscale_ok = 1;
 	tcp_opt->snd_wscale = options & TS_OPT_WSCALE_MASK;
 
-	return sysctl_tcp_window_scaling != 0;
+	return net->ipv4.sysctl_tcp_window_scaling != 0;
 }
 EXPORT_SYMBOL(cookie_timestamp_decode);
 
@@ -312,14 +313,16 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
 
 	/* check for timestamp cookie support */
 	memset(&tcp_opt, 0, sizeof(tcp_opt));
-	tcp_parse_options(skb, &tcp_opt, 0, NULL);
+	tcp_parse_options(sock_net(sk), skb, &tcp_opt, 0, NULL);
 
 	if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) {
-		tsoff = secure_tcp_ts_off(ip_hdr(skb)->daddr, ip_hdr(skb)->saddr);
+		tsoff = secure_tcp_ts_off(sock_net(sk),
+					  ip_hdr(skb)->daddr,
+					  ip_hdr(skb)->saddr);
 		tcp_opt.rcv_tsecr -= tsoff;
 	}
 
-	if (!cookie_timestamp_decode(&tcp_opt))
+	if (!cookie_timestamp_decode(sock_net(sk), &tcp_opt))
 		goto out;
 
 	ret = NULL;
diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c
index 86957e9cd6c6..7065234a89a5 100644
--- a/net/ipv4/sysctl_net_ipv4.c
+++ b/net/ipv4/sysctl_net_ipv4.c
@@ -365,27 +365,6 @@ static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
 
 static struct ctl_table ipv4_table[] = {
 	{
-		.procname	= "tcp_timestamps",
-		.data		= &sysctl_tcp_timestamps,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
-		.procname	= "tcp_window_scaling",
-		.data		= &sysctl_tcp_window_scaling,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
-		.procname	= "tcp_sack",
-		.data		= &sysctl_tcp_sack,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
 		.procname	= "tcp_retrans_collapse",
 		.data		= &sysctl_tcp_retrans_collapse,
 		.maxlen		= sizeof(int),
@@ -1116,6 +1095,27 @@ static struct ctl_table ipv4_net_table[] = {
 		.extra2		= &one,
 	},
 #endif
+	{
+		.procname	= "tcp_sack",
+		.data		= &init_net.ipv4.sysctl_tcp_sack,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "tcp_window_scaling",
+		.data		= &init_net.ipv4.sysctl_tcp_window_scaling,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "tcp_timestamps",
+		.data		= &init_net.ipv4.sysctl_tcp_timestamps,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
 	{ }
 };
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 4ea8ec5c7bb4..2ab7e2fa9bb9 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -76,9 +76,6 @@
 #include <asm/unaligned.h>
 #include <linux/errqueue.h>
 
-int sysctl_tcp_timestamps __read_mostly = 1;
-int sysctl_tcp_window_scaling __read_mostly = 1;
-int sysctl_tcp_sack __read_mostly = 1;
 int sysctl_tcp_fack __read_mostly;
 int sysctl_tcp_max_reordering __read_mostly = 300;
 int sysctl_tcp_dsack __read_mostly = 1;
@@ -3724,7 +3721,8 @@ static void tcp_parse_fastopen_option(int len, const unsigned char *cookie,
  * But, this can also be called on packets in the established flow when
  * the fast version below fails.
  */
-void tcp_parse_options(const struct sk_buff *skb,
+void tcp_parse_options(const struct net *net,
+		       const struct sk_buff *skb,
 		       struct tcp_options_received *opt_rx, int estab,
 		       struct tcp_fastopen_cookie *foc)
 {
@@ -3765,7 +3763,7 @@ void tcp_parse_options(const struct sk_buff *skb,
 				break;
 			case TCPOPT_WINDOW:
 				if (opsize == TCPOLEN_WINDOW && th->syn &&
-				    !estab && sysctl_tcp_window_scaling) {
+				    !estab && net->ipv4.sysctl_tcp_window_scaling) {
 					__u8 snd_wscale = *(__u8 *)ptr;
 					opt_rx->wscale_ok = 1;
 					if (snd_wscale > TCP_MAX_WSCALE) {
@@ -3781,7 +3779,7 @@ void tcp_parse_options(const struct sk_buff *skb,
 			case TCPOPT_TIMESTAMP:
 				if ((opsize == TCPOLEN_TIMESTAMP) &&
 				    ((estab && opt_rx->tstamp_ok) ||
-				     (!estab && sysctl_tcp_timestamps))) {
+				     (!estab && net->ipv4.sysctl_tcp_timestamps))) {
 					opt_rx->saw_tstamp = 1;
 					opt_rx->rcv_tsval = get_unaligned_be32(ptr);
 					opt_rx->rcv_tsecr = get_unaligned_be32(ptr + 4);
@@ -3789,7 +3787,7 @@ void tcp_parse_options(const struct sk_buff *skb,
 				break;
 			case TCPOPT_SACK_PERM:
 				if (opsize == TCPOLEN_SACK_PERM && th->syn &&
-				    !estab && sysctl_tcp_sack) {
+				    !estab && net->ipv4.sysctl_tcp_sack) {
 					opt_rx->sack_ok = TCP_SACK_SEEN;
 					tcp_sack_reset(opt_rx);
 				}
@@ -3858,7 +3856,8 @@ static bool tcp_parse_aligned_timestamp(struct tcp_sock *tp, const struct tcphdr
 /* Fast parse options. This hopes to only see timestamps.
  * If it is wrong it falls back on tcp_parse_options().
  */
-static bool tcp_fast_parse_options(const struct sk_buff *skb,
+static bool tcp_fast_parse_options(const struct net *net,
+				   const struct sk_buff *skb,
 				   const struct tcphdr *th, struct tcp_sock *tp)
 {
 	/* In the spirit of fast parsing, compare doff directly to constant
@@ -3873,7 +3872,7 @@ static bool tcp_fast_parse_options(const struct sk_buff *skb,
 			return true;
 	}
 
-	tcp_parse_options(skb, &tp->rx_opt, 1, NULL);
+	tcp_parse_options(net, skb, &tp->rx_opt, 1, NULL);
 	if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr)
 		tp->rx_opt.rcv_tsecr -= tp->tsoffset;
 
@@ -5234,7 +5233,8 @@ static bool tcp_validate_incoming(struct sock *sk, struct sk_buff *skb,
 	bool rst_seq_match = false;
 
 	/* RFC1323: H1. Apply PAWS check first. */
-	if (tcp_fast_parse_options(skb, th, tp) && tp->rx_opt.saw_tstamp &&
+	if (tcp_fast_parse_options(sock_net(sk), skb, th, tp) &&
+	    tp->rx_opt.saw_tstamp &&
 	    tcp_paws_discard(sk, skb)) {
 		if (!th->rst) {
 			NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED);
@@ -5605,7 +5605,7 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack,
 		/* Get original SYNACK MSS value if user MSS sets mss_clamp */
 		tcp_clear_options(&opt);
 		opt.user_mss = opt.mss_clamp = 0;
-		tcp_parse_options(synack, &opt, 0, NULL);
+		tcp_parse_options(sock_net(sk), synack, &opt, 0, NULL);
 		mss = opt.mss_clamp;
 	}
 
@@ -5659,7 +5659,7 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
 	int saved_clamp = tp->rx_opt.mss_clamp;
 	bool fastopen_fail;
 
-	tcp_parse_options(skb, &tp->rx_opt, 0, &foc);
+	tcp_parse_options(sock_net(sk), skb, &tp->rx_opt, 0, &foc);
 	if (tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr)
 		tp->rx_opt.rcv_tsecr -= tp->tsoffset;
 
@@ -6332,7 +6332,8 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 	tcp_clear_options(&tmp_opt);
 	tmp_opt.mss_clamp = af_ops->mss_clamp;
 	tmp_opt.user_mss  = tp->rx_opt.user_mss;
-	tcp_parse_options(skb, &tmp_opt, 0, want_cookie ? NULL : &foc);
+	tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0,
+			  want_cookie ? NULL : &foc);
 
 	if (want_cookie && !tmp_opt.saw_tstamp)
 		tcp_clear_options(&tmp_opt);
@@ -6350,7 +6351,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 		goto drop_and_free;
 
 	if (tmp_opt.tstamp_ok)
-		tcp_rsk(req)->ts_off = af_ops->init_ts_off(skb);
+		tcp_rsk(req)->ts_off = af_ops->init_ts_off(net, skb);
 
 	if (!want_cookie && !isn) {
 		/* Kill the following clause, if you dislike this way. */
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 191b2f78b19d..13c7ae7d4504 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -102,10 +102,9 @@ static u32 tcp_v4_init_seq(const struct sk_buff *skb)
 			      tcp_hdr(skb)->source);
 }
 
-static u32 tcp_v4_init_ts_off(const struct sk_buff *skb)
+static u32 tcp_v4_init_ts_off(const struct net *net, const struct sk_buff *skb)
 {
-	return secure_tcp_ts_off(ip_hdr(skb)->daddr,
-				 ip_hdr(skb)->saddr);
+	return secure_tcp_ts_off(net, ip_hdr(skb)->daddr, ip_hdr(skb)->saddr);
 }
 
 int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
@@ -242,7 +241,8 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 						       inet->inet_daddr,
 						       inet->inet_sport,
 						       usin->sin_port);
-		tp->tsoffset = secure_tcp_ts_off(inet->inet_saddr,
+		tp->tsoffset = secure_tcp_ts_off(sock_net(sk),
+						 inet->inet_saddr,
 						 inet->inet_daddr);
 	}
 
@@ -2465,6 +2465,9 @@ static int __net_init tcp_sk_init(struct net *net)
 	net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo;
 
 	net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256);
+	net->ipv4.sysctl_tcp_sack = 1;
+	net->ipv4.sysctl_tcp_window_scaling = 1;
+	net->ipv4.sysctl_tcp_timestamps = 1;
 
 	return 0;
 fail:
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index d0642df73044..d30ee31e94eb 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -98,7 +98,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb,
 
 	tmp_opt.saw_tstamp = 0;
 	if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) {
-		tcp_parse_options(skb, &tmp_opt, 0, NULL);
+		tcp_parse_options(twsk_net(tw), skb, &tmp_opt, 0, NULL);
 
 		if (tmp_opt.saw_tstamp) {
 			if (tmp_opt.rcv_tsecr)
@@ -559,7 +559,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
 
 	tmp_opt.saw_tstamp = 0;
 	if (th->doff > (sizeof(struct tcphdr)>>2)) {
-		tcp_parse_options(skb, &tmp_opt, 0, NULL);
+		tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0, NULL);
 
 		if (tmp_opt.saw_tstamp) {
 			tmp_opt.ts_recent = req->ts_recent;
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e3aab1c1cf78..9a9c395b6235 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -569,18 +569,18 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb,
 	opts->mss = tcp_advertise_mss(sk);
 	remaining -= TCPOLEN_MSS_ALIGNED;
 
-	if (likely(sysctl_tcp_timestamps && !*md5)) {
+	if (likely(sock_net(sk)->ipv4.sysctl_tcp_timestamps && !*md5)) {
 		opts->options |= OPTION_TS;
 		opts->tsval = tcp_skb_timestamp(skb) + tp->tsoffset;
 		opts->tsecr = tp->rx_opt.ts_recent;
 		remaining -= TCPOLEN_TSTAMP_ALIGNED;
 	}
-	if (likely(sysctl_tcp_window_scaling)) {
+	if (likely(sock_net(sk)->ipv4.sysctl_tcp_window_scaling)) {
 		opts->ws = tp->rx_opt.rcv_wscale;
 		opts->options |= OPTION_WSCALE;
 		remaining -= TCPOLEN_WSCALE_ALIGNED;
 	}
-	if (likely(sysctl_tcp_sack)) {
+	if (likely(sock_net(sk)->ipv4.sysctl_tcp_sack)) {
 		opts->options |= OPTION_SACK_ADVERTISE;
 		if (unlikely(!(OPTION_TS & opts->options)))
 			remaining -= TCPOLEN_SACKPERM_ALIGNED;
@@ -3271,8 +3271,9 @@ static void tcp_connect_init(struct sock *sk)
 	/* We'll fix this up when we get a response from the other end.
 	 * See tcp_input.c:tcp_rcv_state_process case TCP_SYN_SENT.
 	 */
-	tp->tcp_header_len = sizeof(struct tcphdr) +
-		(sysctl_tcp_timestamps ? TCPOLEN_TSTAMP_ALIGNED : 0);
+	tp->tcp_header_len = sizeof(struct tcphdr);
+	if (sock_net(sk)->ipv4.sysctl_tcp_timestamps)
+		tp->tcp_header_len += TCPOLEN_TSTAMP_ALIGNED;
 
 #ifdef CONFIG_TCP_MD5SIG
 	if (tp->af_specific->md5_lookup(sk, sk))
@@ -3303,7 +3304,7 @@ static void tcp_connect_init(struct sock *sk)
 				  tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
 				  &tp->rcv_wnd,
 				  &tp->window_clamp,
-				  sysctl_tcp_window_scaling,
+				  sock_net(sk)->ipv4.sysctl_tcp_window_scaling,
 				  &rcv_wscale,
 				  dst_metric(dst, RTAX_INITRWND));
 
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index 971823359f5b..2f7e99af67db 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -162,15 +162,16 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 
 	/* check for timestamp cookie support */
 	memset(&tcp_opt, 0, sizeof(tcp_opt));
-	tcp_parse_options(skb, &tcp_opt, 0, NULL);
+	tcp_parse_options(sock_net(sk), skb, &tcp_opt, 0, NULL);
 
 	if (tcp_opt.saw_tstamp && tcp_opt.rcv_tsecr) {
-		tsoff = secure_tcpv6_ts_off(ipv6_hdr(skb)->daddr.s6_addr32,
+		tsoff = secure_tcpv6_ts_off(sock_net(sk),
+					    ipv6_hdr(skb)->daddr.s6_addr32,
 					    ipv6_hdr(skb)->saddr.s6_addr32);
 		tcp_opt.rcv_tsecr -= tsoff;
 	}
 
-	if (!cookie_timestamp_decode(&tcp_opt))
+	if (!cookie_timestamp_decode(sock_net(sk), &tcp_opt))
 		goto out;
 
 	ret = NULL;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 233edfabe1db..5a525426fe93 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -109,9 +109,9 @@ static u32 tcp_v6_init_seq(const struct sk_buff *skb)
 				tcp_hdr(skb)->source);
 }
 
-static u32 tcp_v6_init_ts_off(const struct sk_buff *skb)
+static u32 tcp_v6_init_ts_off(const struct net *net, const struct sk_buff *skb)
 {
-	return secure_tcpv6_ts_off(ipv6_hdr(skb)->daddr.s6_addr32,
+	return secure_tcpv6_ts_off(net, ipv6_hdr(skb)->daddr.s6_addr32,
 				   ipv6_hdr(skb)->saddr.s6_addr32);
 }
 
@@ -292,7 +292,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 							 sk->sk_v6_daddr.s6_addr32,
 							 inet->inet_sport,
 							 inet->inet_dport);
-		tp->tsoffset = secure_tcpv6_ts_off(np->saddr.s6_addr32,
+		tp->tsoffset = secure_tcpv6_ts_off(sock_net(sk),
+						   np->saddr.s6_addr32,
 						   sk->sk_v6_daddr.s6_addr32);
 	}