Merge tag 'v5.10.14' into linux-5.10.y-rt

This is the 5.10.14 stable release

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

4 files changed, 31 insertions, 8 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 6bf066f924c1..fac5c1469cee 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2845,7 +2845,8 @@ static void tcp_identify_packet_loss(struct sock *sk, int *ack_flag)
 	} else if (tcp_is_rack(sk)) {
 		u32 prior_retrans = tp->retrans_out;
 
-		tcp_rack_mark_lost(sk);
+		if (tcp_rack_mark_lost(sk))
+			*ack_flag &= ~FLAG_SET_XMIT_TIMER;
 		if (prior_retrans > tp->retrans_out)
 			*ack_flag |= FLAG_LOST_RETRANS;
 	}
@@ -3378,8 +3379,8 @@ static void tcp_ack_probe(struct sock *sk)
 	} else {
 		unsigned long when = tcp_probe0_when(sk, TCP_RTO_MAX);
 
-		tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
-				     when, TCP_RTO_MAX);
+		when = tcp_clamp_probe0_to_user_timeout(sk, when);
+		tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, when, TCP_RTO_MAX);
 	}
 }
 
@@ -3802,9 +3803,6 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 
 	if (tp->tlp_high_seq)
 		tcp_process_tlp_ack(sk, ack, flag);
-	/* If needed, reset TLP/RTO timer; RACK may later override this. */
-	if (flag & FLAG_SET_XMIT_TIMER)
-		tcp_set_xmit_timer(sk);
 
 	if (tcp_ack_is_dubious(sk, flag)) {
 		if (!(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP))) {
@@ -3817,6 +3815,10 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 				      &rexmit);
 	}
 
+	/* If needed, reset TLP/RTO timer when RACK doesn't set. */
+	if (flag & FLAG_SET_XMIT_TIMER)
+		tcp_set_xmit_timer(sk);
+
 	if ((flag & FLAG_FORWARD_PROGRESS) || !(flag & FLAG_NOT_DUP))
 		sk_dst_confirm(sk);
 
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e58e2589d7f9..f99494637ff4 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -4095,6 +4095,8 @@ void tcp_send_probe0(struct sock *sk)
 		 */
 		timeout = TCP_RESOURCE_PROBE_INTERVAL;
 	}
+
+	timeout = tcp_clamp_probe0_to_user_timeout(sk, timeout);
 	tcp_reset_xmit_timer(sk, ICSK_TIME_PROBE0, timeout, TCP_RTO_MAX);
 }
 
diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c
index f65a3ddd0d58..31fc178f42c0 100644
--- a/net/ipv4/tcp_recovery.c
+++ b/net/ipv4/tcp_recovery.c
@@ -96,13 +96,13 @@ static void tcp_rack_detect_loss(struct sock *sk, u32 *reo_timeout)
 	}
 }
 
-void tcp_rack_mark_lost(struct sock *sk)
+bool tcp_rack_mark_lost(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	u32 timeout;
 
 	if (!tp->rack.advanced)
-		return;
+		return false;
 
 	/* Reset the advanced flag to avoid unnecessary queue scanning */
 	tp->rack.advanced = 0;
@@ -112,6 +112,7 @@ void tcp_rack_mark_lost(struct sock *sk)
 		inet_csk_reset_xmit_timer(sk, ICSK_TIME_REO_TIMEOUT,
 					  timeout, inet_csk(sk)->icsk_rto);
 	}
+	return !!timeout;
 }
 
 /* Record the most recently (re)sent time among the (s)acked packets
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index faa92948441b..4ef08079ccfa 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -40,6 +40,24 @@ static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk)
 	return min_t(u32, icsk->icsk_rto, msecs_to_jiffies(remaining));
 }
 
+u32 tcp_clamp_probe0_to_user_timeout(const struct sock *sk, u32 when)
+{
+	struct inet_connection_sock *icsk = inet_csk(sk);
+	u32 remaining;
+	s32 elapsed;
+
+	if (!icsk->icsk_user_timeout || !icsk->icsk_probes_tstamp)
+		return when;
+
+	elapsed = tcp_jiffies32 - icsk->icsk_probes_tstamp;
+	if (unlikely(elapsed < 0))
+		elapsed = 0;
+	remaining = msecs_to_jiffies(icsk->icsk_user_timeout) - elapsed;
+	remaining = max_t(u32, remaining, TCP_TIMEOUT_MIN);
+
+	return min_t(u32, remaining, when);
+}
+
 /**
  *  tcp_write_err() - close socket and save error info
  *  @sk:  The socket the error has appeared on.