diff --git a/src/net/dial.go b/src/net/dial.go
index 60ab0f2973c..d8be1c222d0 100644
--- a/src/net/dial.go
+++ b/src/net/dial.go
@@ -529,20 +529,21 @@ func (sd *sysDialer) dialSerial(ctx context.Context, ras addrList) (Conn, error)
 		default:
 		}
 
-		deadline, _ := ctx.Deadline()
-		partialDeadline, err := partialDeadline(time.Now(), deadline, len(ras)-i)
-		if err != nil {
-			// Ran out of time.
-			if firstErr == nil {
-				firstErr = &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: err}
-			}
-			break
-		}
 		dialCtx := ctx
-		if partialDeadline.Before(deadline) {
-			var cancel context.CancelFunc
-			dialCtx, cancel = context.WithDeadline(ctx, partialDeadline)
-			defer cancel()
+		if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
+			partialDeadline, err := partialDeadline(time.Now(), deadline, len(ras)-i)
+			if err != nil {
+				// Ran out of time.
+				if firstErr == nil {
+					firstErr = &OpError{Op: "dial", Net: sd.network, Source: sd.LocalAddr, Addr: ra, Err: err}
+				}
+				break
+			}
+			if partialDeadline.Before(deadline) {
+				var cancel context.CancelFunc
+				dialCtx, cancel = context.WithDeadline(ctx, partialDeadline)
+				defer cancel()
+			}
 		}
 
 		c, err := sd.dialSingle(dialCtx, ra)
diff --git a/src/net/dial_test.go b/src/net/dial_test.go
index 2eddac8284b..4312a6df714 100644
--- a/src/net/dial_test.go
+++ b/src/net/dial_test.go
@@ -980,3 +980,32 @@ func mustHaveExternalNetwork(t *testing.T) {
 		testenv.MustHaveExternalNetwork(t)
 	}
 }
+
+type contextWithNonZeroDeadline struct {
+	context.Context
+}
+
+func (contextWithNonZeroDeadline) Deadline() (time.Time, bool) {
+	// Return non-zero time.Time value with false indicating that no deadline is set.
+	return time.Unix(0, 0), false
+}
+
+func TestDialWithNonZeroDeadline(t *testing.T) {
+	ln, err := newLocalListener("tcp")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer ln.Close()
+	_, port, err := SplitHostPort(ln.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := contextWithNonZeroDeadline{Context: context.Background()}
+	var dialer Dialer
+	c, err := dialer.DialContext(ctx, "tcp", JoinHostPort("", port))
+	if err != nil {
+		t.Fatal(err)
+	}
+	c.Close()
+}
diff --git a/src/net/fd_unix.go b/src/net/fd_unix.go
index a6d64538102..da88c74f6b4 100644
--- a/src/net/fd_unix.go
+++ b/src/net/fd_unix.go
@@ -96,7 +96,7 @@ func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (rsa sysc
 	if err := fd.pfd.Init(fd.net, true); err != nil {
 		return nil, err
 	}
-	if deadline, _ := ctx.Deadline(); !deadline.IsZero() {
+	if deadline, hasDeadline := ctx.Deadline(); hasDeadline {
 		fd.pfd.SetWriteDeadline(deadline)
 		defer fd.pfd.SetWriteDeadline(noDeadline)
 	}