From 00727feed6efa6f5cbce471f7ed3b2c174d817e0 Mon Sep 17 00:00:00 2001
From: ICHINOSE Shogo <shogo82148@gmail.com>
Date: Fri, 22 Mar 2024 23:18:57 +0900
Subject: [PATCH 1/4] Add test for Issue1567

---
 driver_test.go | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/driver_test.go b/driver_test.go
index 6b52650c2..11040d072 100644
--- a/driver_test.go
+++ b/driver_test.go
@@ -20,6 +20,7 @@ import (
 	"io"
 	"log"
 	"math"
+	mrand "math/rand"
 	"net"
 	"net/url"
 	"os"
@@ -3577,3 +3578,31 @@ func runCallCommand(dbt *DBTest, query, name string) {
 		}
 	}
 }
+
+func TestIssue1567(t *testing.T) {
+	// enable TLS.
+	runTests(t, dsn+"&tls=skip-verify", func(dbt *DBTest) {
+		// disable connection pooling.
+		// data race happens when new connection is created.
+		dbt.db.SetMaxIdleConns(0)
+
+		// estimate round trip time.
+		start := time.Now()
+		if err := dbt.db.PingContext(context.Background()); err != nil {
+			t.Fatal(err)
+		}
+		rtt := time.Since(start)
+
+		count := 1000
+		if testing.Short() {
+			count = 10
+		}
+
+		for i := 0; i < count; i++ {
+			timeout := time.Duration(mrand.Int63n(int64(rtt)))
+			ctx, cancel := context.WithTimeout(context.Background(), timeout)
+			dbt.db.PingContext(ctx)
+			cancel()
+		}
+	})
+}

From 93f1a648e893b1611e52aa7c41bb2c16bc8a13e2 Mon Sep 17 00:00:00 2001
From: ICHINOSE Shogo <shogo82148@gmail.com>
Date: Fri, 22 Mar 2024 23:29:48 +0900
Subject: [PATCH 2/4] fix Data race between mysqlConn.cleanup() and
 writeHandshakeResponsePacket

close #1567
---
 connection.go | 6 +-----
 connector.go  | 2 +-
 packets.go    | 1 -
 3 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/connection.go b/connection.go
index f3656f0e6..722352a7e 100644
--- a/connection.go
+++ b/connection.go
@@ -153,11 +153,7 @@ func (mc *mysqlConn) cleanup() {
 
 	// Makes cleanup idempotent
 	close(mc.closech)
-	nc := mc.netConn
-	if nc == nil {
-		return
-	}
-	if err := nc.Close(); err != nil {
+	if err := mc.rawConn.Close(); err != nil {
 		mc.log(err)
 	}
 	// This function can be called from multiple goroutines.
diff --git a/connector.go b/connector.go
index a0ee62839..b67077596 100644
--- a/connector.go
+++ b/connector.go
@@ -102,10 +102,10 @@ func (c *connector) Connect(ctx context.Context) (driver.Conn, error) {
 		nd := net.Dialer{Timeout: mc.cfg.Timeout}
 		mc.netConn, err = nd.DialContext(ctx, mc.cfg.Net, mc.cfg.Addr)
 	}
-
 	if err != nil {
 		return nil, err
 	}
+	mc.rawConn = mc.netConn
 
 	// Enable TCP Keepalives on TCP connections
 	if tc, ok := mc.netConn.(*net.TCPConn); ok {
diff --git a/packets.go b/packets.go
index d727f00fe..90a34728b 100644
--- a/packets.go
+++ b/packets.go
@@ -351,7 +351,6 @@ func (mc *mysqlConn) writeHandshakeResponsePacket(authResp []byte, plugin string
 		if err := tlsConn.Handshake(); err != nil {
 			return err
 		}
-		mc.rawConn = mc.netConn
 		mc.netConn = tlsConn
 		mc.buf.nc = tlsConn
 	}

From d05ec232fe25697cf8915bc479ceccd9b7f9204b Mon Sep 17 00:00:00 2001
From: ICHINOSE Shogo <shogo82148@gmail.com>
Date: Fri, 22 Mar 2024 23:33:26 +0900
Subject: [PATCH 3/4] Fix connection cleanup to handle nil rawConn

---
 connection.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/connection.go b/connection.go
index 722352a7e..7b8abeb00 100644
--- a/connection.go
+++ b/connection.go
@@ -153,7 +153,11 @@ func (mc *mysqlConn) cleanup() {
 
 	// Makes cleanup idempotent
 	close(mc.closech)
-	if err := mc.rawConn.Close(); err != nil {
+	conn := mc.rawConn
+	if conn == nil {
+		return
+	}
+	if err := conn.Close(); err != nil {
 		mc.log(err)
 	}
 	// This function can be called from multiple goroutines.

From 73abfe6778385648a635b07dd93dd6703219d787 Mon Sep 17 00:00:00 2001
From: ICHINOSE Shogo <shogo82148@gmail.com>
Date: Fri, 22 Mar 2024 23:41:17 +0900
Subject: [PATCH 4/4] In some environments, rtt may become 0, so set it to at
 least 1ms.

---
 driver_test.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/driver_test.go b/driver_test.go
index 11040d072..4fd196d4b 100644
--- a/driver_test.go
+++ b/driver_test.go
@@ -3592,6 +3592,10 @@ func TestIssue1567(t *testing.T) {
 			t.Fatal(err)
 		}
 		rtt := time.Since(start)
+		if rtt <= 0 {
+			// In some environments, rtt may become 0, so set it to at least 1ms.
+			rtt = time.Millisecond
+		}
 
 		count := 1000
 		if testing.Short() {