4 files changed, 28 insertions, 10 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index bff62fc87b8e..f45f2a12f37b 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -902,6 +902,10 @@ static int ip_error(struct sk_buff *skb)
 	bool send;
 	int code;
 
+	/* IP on this device is disabled. */
+	if (!in_dev)
+		goto out;
+
 	net = dev_net(rt->dst.dev);
 	if (!IN_DEV_FORWARD(in_dev)) {
 		switch (rt->dst.error) {
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 46efa03d2b11..f1377f2a0472 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -402,6 +402,7 @@ void tcp_init_sock(struct sock *sk)
 	tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
 	tp->snd_cwnd_clamp = ~0;
 	tp->mss_cache = TCP_MSS_DEFAULT;
+	u64_stats_init(&tp->syncp);
 
 	tp->reordering = sysctl_tcp_reordering;
 	tcp_enable_early_retrans(tp);
@@ -2598,6 +2599,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	const struct tcp_sock *tp = tcp_sk(sk);
 	const struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 now = tcp_time_stamp;
+	unsigned int start;
 	u32 rate;
 
 	memset(info, 0, sizeof(*info));
@@ -2665,10 +2667,11 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	rate = READ_ONCE(sk->sk_max_pacing_rate);
 	info->tcpi_max_pacing_rate = rate != ~0U ? rate : ~0ULL;
 
-	spin_lock_bh(&sk->sk_lock.slock);
-	info->tcpi_bytes_acked = tp->bytes_acked;
-	info->tcpi_bytes_received = tp->bytes_received;
-	spin_unlock_bh(&sk->sk_lock.slock);
+	do {
+		start = u64_stats_fetch_begin_irq(&tp->syncp);
+		info->tcpi_bytes_acked = tp->bytes_acked;
+		info->tcpi_bytes_received = tp->bytes_received;
+	} while (u64_stats_fetch_retry_irq(&tp->syncp, start));
 }
 EXPORT_SYMBOL_GPL(tcp_get_info);
 
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 3c673d5e6cff..46b087a27503 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -206,6 +206,10 @@ static bool tcp_fastopen_create_child(struct sock *sk,
 			skb_set_owner_r(skb2, child);
 			__skb_queue_tail(&child->sk_receive_queue, skb2);
 			tp->syn_data_acked = 1;
+
+			/* u64_stats_update_begin(&tp->syncp) not needed here,
+			 * as we certainly are not changing upper 32bit value (0)
+			 */
 			tp->bytes_received = end_seq - TCP_SKB_CB(skb)->seq - 1;
 		} else {
 			end_seq = TCP_SKB_CB(skb)->seq + 1;
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index bc790ea9960f..c9ab964189a0 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2698,16 +2698,21 @@ static void tcp_process_loss(struct sock *sk, int flag, bool is_dupack)
 	struct tcp_sock *tp = tcp_sk(sk);
 	bool recovered = !before(tp->snd_una, tp->high_seq);
 
+	if ((flag & FLAG_SND_UNA_ADVANCED) &&
+	    tcp_try_undo_loss(sk, false))
+		return;
+
 	if (tp->frto) { /* F-RTO RFC5682 sec 3.1 (sack enhanced version). */
 		/* Step 3.b. A timeout is spurious if not all data are
 		 * lost, i.e., never-retransmitted data are (s)acked.
 		 */
-		if (tcp_try_undo_loss(sk, flag & FLAG_ORIG_SACK_ACKED))
+		if ((flag & FLAG_ORIG_SACK_ACKED) &&
+		    tcp_try_undo_loss(sk, true))
 			return;
 
-		if (after(tp->snd_nxt, tp->high_seq) &&
-		    (flag & FLAG_DATA_SACKED || is_dupack)) {
-			tp->frto = 0; /* Loss was real: 2nd part of step 3.a */
+		if (after(tp->snd_nxt, tp->high_seq)) {
+			if (flag & FLAG_DATA_SACKED || is_dupack)
+				tp->frto = 0; /* Step 3.a. loss was real */
 		} else if (flag & FLAG_SND_UNA_ADVANCED && !recovered) {
 			tp->high_seq = tp->snd_nxt;
 			__tcp_push_pending_frames(sk, tcp_current_mss(sk),
@@ -2732,8 +2737,6 @@ static void tcp_process_loss(struct sock *sk, int flag, bool is_dupack)
 		else if (flag & FLAG_SND_UNA_ADVANCED)
 			tcp_reset_reno_sack(tp);
 	}
-	if (tcp_try_undo_loss(sk, false))
-		return;
 	tcp_xmit_retransmit_queue(sk);
 }
 
@@ -3283,7 +3286,9 @@ static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack)
 {
 	u32 delta = ack - tp->snd_una;
 
+	u64_stats_update_begin(&tp->syncp);
 	tp->bytes_acked += delta;
+	u64_stats_update_end(&tp->syncp);
 	tp->snd_una = ack;
 }
 
@@ -3292,7 +3297,9 @@ static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq)
 {
 	u32 delta = seq - tp->rcv_nxt;
 
+	u64_stats_update_begin(&tp->syncp);
 	tp->bytes_received += delta;
+	u64_stats_update_end(&tp->syncp);
 	tp->rcv_nxt = seq;
 }