multi: thread context through Fail payment functions

diff --git a/payments/db/interface.go b/payments/db/interface.go
index 45d0e9a..2d2c47b 100644
--- a/payments/db/interface.go
+++ b/payments/db/interface.go
@@ -99,7 +99,7 @@ type PaymentControl interface {
 	// invoking this method, InitPayment should return nil on its next call
 	// for this payment hash, allowing the user to make a subsequent
 	// payment.
-	Fail(lntypes.Hash, FailureReason) (*MPPayment, error)
+	Fail(context.Context, lntypes.Hash, FailureReason) (*MPPayment, error)
 
 	// DeleteFailedAttempts removes all failed HTLCs from the db. It should
 	// be called for a given payment whenever all inflight htlcs are
diff --git a/payments/db/kv_store.go b/payments/db/kv_store.go
index 59fe24f..285074b 100644
--- a/payments/db/kv_store.go
+++ b/payments/db/kv_store.go
@@ -528,7 +528,7 @@ func (p *KVStore) updateHtlcKey(paymentHash lntypes.Hash,
 // payment failed. After invoking this method, InitPayment should return nil on
 // its next call for this payment hash, allowing the switch to make a
 // subsequent payment.
-func (p *KVStore) Fail(paymentHash lntypes.Hash,
+func (p *KVStore) Fail(_ context.Context, paymentHash lntypes.Hash,
 	reason FailureReason) (*MPPayment, error) {
 
 	var (
diff --git a/payments/db/kv_store_test.go b/payments/db/kv_store_test.go
index ee8412a..de3fc4a 100644
--- a/payments/db/kv_store_test.go
+++ b/payments/db/kv_store_test.go
@@ -112,7 +112,7 @@ func TestKVStoreDeleteNonInFlight(t *testing.T) {
 			// Fail the payment, which should moved it to Failed.
 			failReason := FailureReasonNoRoute
 			_, err = paymentDB.Fail(
-				info.PaymentIdentifier, failReason,
+				ctx, info.PaymentIdentifier, failReason,
 			)
 			if err != nil {
 				t.Fatalf("unable to fail payment hash: %v", err)
diff --git a/payments/db/payment_test.go b/payments/db/payment_test.go
index 879dfb1..5f1ab69 100644
--- a/payments/db/payment_test.go
+++ b/payments/db/payment_test.go
@@ -191,8 +191,9 @@ func createTestPayments(t *testing.T, p DB, payments []*payment) {
 			require.NoError(t, err, "unable to fail htlc")
 
 			failReason := FailureReasonNoRoute
-			_, err = p.Fail(info.PaymentIdentifier,
-				failReason)
+			_, err = p.Fail(
+				ctx, info.PaymentIdentifier, failReason,
+			)
 			require.NoError(t, err, "unable to fail payment hash")
 
 		// Settle the attempt
@@ -1667,7 +1668,7 @@ func TestFailsWithoutInFlight(t *testing.T) {
 
 	// Calling Fail should return an error.
 	_, err = paymentDB.Fail(
-		info.PaymentIdentifier, FailureReasonNoRoute,
+		t.Context(), info.PaymentIdentifier, FailureReasonNoRoute,
 	)
 	require.ErrorIs(t, err, ErrPaymentNotInitiated)
 }
@@ -1843,7 +1844,7 @@ func TestSwitchFail(t *testing.T) {
 
 	// Fail the payment, which should moved it to Failed.
 	failReason := FailureReasonNoRoute
-	_, err = paymentDB.Fail(info.PaymentIdentifier, failReason)
+	_, err = paymentDB.Fail(ctx, info.PaymentIdentifier, failReason)
 	require.NoError(t, err, "unable to fail payment hash")
 
 	// Verify the status is indeed Failed.
@@ -2139,7 +2140,7 @@ func TestMultiShard(t *testing.T) {
 			// a terminal state.
 			failReason := FailureReasonNoRoute
 			_, err = paymentDB.Fail(
-				info.PaymentIdentifier, failReason,
+				ctx, info.PaymentIdentifier, failReason,
 			)
 			if err != nil {
 				t.Fatalf("unable to fail payment hash: %v", err)
@@ -2232,7 +2233,7 @@ func TestMultiShard(t *testing.T) {
 			// syncing.
 			failReason := FailureReasonPaymentDetails
 			_, err = paymentDB.Fail(
-				info.PaymentIdentifier, failReason,
+				ctx, info.PaymentIdentifier, failReason,
 			)
 			require.NoError(t, err, "unable to fail")
 		}
diff --git a/payments/db/sql_store.go b/payments/db/sql_store.go
index a921a12..a9863b5 100644
--- a/payments/db/sql_store.go
+++ b/payments/db/sql_store.go
@@ -1782,11 +1782,9 @@ func (s *SQLStore) FailAttempt(ctx context.Context, paymentHash lntypes.Hash,
 // This method is part of the PaymentControl interface, which is embedded in
 // the PaymentWriter interface and ultimately the DB interface. It represents
 // step 4 in the payment lifecycle control flow.
-func (s *SQLStore) Fail(paymentHash lntypes.Hash,
+func (s *SQLStore) Fail(ctx context.Context, paymentHash lntypes.Hash,
 	reason FailureReason) (*MPPayment, error) {
 
-	ctx := context.TODO()
-
 	var mpPayment *MPPayment
 
 	err := s.db.ExecTx(ctx, sqldb.WriteTxOpt(), func(db SQLQueries) error {
diff --git a/routing/control_tower.go b/routing/control_tower.go
index cbb79d4..b39a378 100644
--- a/routing/control_tower.go
+++ b/routing/control_tower.go
@@ -66,7 +66,8 @@ type ControlTower interface {
 	// payment.
 	//
 	// NOTE: Subscribers should be notified by the new state of the payment.
-	FailPayment(lntypes.Hash, paymentsdb.FailureReason) error
+	FailPayment(context.Context, lntypes.Hash,
+		paymentsdb.FailureReason) error
 
 	// FetchInFlightPayments returns all payments with status InFlight.
 	FetchInFlightPayments(ctx context.Context) ([]*paymentsdb.MPPayment,
@@ -272,13 +273,13 @@ func (p *controlTower) FetchPayment(ctx context.Context,
 //
 // NOTE: This method will overwrite the failure reason if the payment is already
 // failed.
-func (p *controlTower) FailPayment(paymentHash lntypes.Hash,
-	reason paymentsdb.FailureReason) error {
+func (p *controlTower) FailPayment(ctx context.Context,
+	paymentHash lntypes.Hash, reason paymentsdb.FailureReason) error {
 
 	p.paymentsMtx.Lock(paymentHash)
 	defer p.paymentsMtx.Unlock(paymentHash)
 
-	payment, err := p.db.Fail(paymentHash, reason)
+	payment, err := p.db.Fail(ctx, paymentHash, reason)
 	if err != nil {
 		return err
 	}
diff --git a/routing/control_tower_test.go b/routing/control_tower_test.go
index 5241d81..c9e8f48 100644
--- a/routing/control_tower_test.go
+++ b/routing/control_tower_test.go
@@ -516,7 +516,8 @@ func testKVStoreSubscribeFail(t *testing.T, registerAttempt,
 
 	// Mark the payment as failed.
 	err = pControl.FailPayment(
-		info.PaymentIdentifier, paymentsdb.FailureReasonTimeout,
+		t.Context(), info.PaymentIdentifier,
+		paymentsdb.FailureReasonTimeout,
 	)
 	if err != nil {
 		t.Fatal(err)
diff --git a/routing/mock_test.go b/routing/mock_test.go
index f10c38a..e72b392 100644
--- a/routing/mock_test.go
+++ b/routing/mock_test.go
@@ -491,7 +491,7 @@ func (m *mockControlTowerOld) FailAttempt(_ context.Context, phash lntypes.Hash,
 	return nil, fmt.Errorf("pid not found")
 }
 
-func (m *mockControlTowerOld) FailPayment(phash lntypes.Hash,
+func (m *mockControlTowerOld) FailPayment(_ context.Context, phash lntypes.Hash,
 	reason paymentsdb.FailureReason) error {
 
 	m.Lock()
@@ -782,7 +782,7 @@ func (m *mockControlTower) FailAttempt(_ context.Context, phash lntypes.Hash,
 	return attempt.(*paymentsdb.HTLCAttempt), args.Error(1)
 }
 
-func (m *mockControlTower) FailPayment(phash lntypes.Hash,
+func (m *mockControlTower) FailPayment(_ context.Context, phash lntypes.Hash,
 	reason paymentsdb.FailureReason) error {
 
 	args := m.Called(phash, reason)
diff --git a/routing/payment_lifecycle.go b/routing/payment_lifecycle.go
index 904d399..37dbd1c 100644
--- a/routing/payment_lifecycle.go
+++ b/routing/payment_lifecycle.go
@@ -364,11 +364,18 @@ func (p *paymentLifecycle) checkContext(ctx context.Context) error {
 				p.identifier.String())
 		}
 
+		// The context is already cancelled at this point, so we create
+		// a new context so the payment can successfully be marked as
+		// failed.
+		cleanupCtx := context.WithoutCancel(ctx)
+
 		// By marking the payment failed, depending on whether it has
 		// inflight HTLCs or not, its status will now either be
 		// `StatusInflight` or `StatusFailed`. In either case, no more
 		// HTLCs will be attempted.
-		err := p.router.cfg.Control.FailPayment(p.identifier, reason)
+		err := p.router.cfg.Control.FailPayment(
+			cleanupCtx, p.identifier, reason,
+		)
 		if err != nil {
 			return fmt.Errorf("FailPayment got %w", err)
 		}
@@ -389,6 +396,8 @@ func (p *paymentLifecycle) checkContext(ctx context.Context) error {
 func (p *paymentLifecycle) requestRoute(
 	ps *paymentsdb.MPPaymentState) (*route.Route, error) {
 
+	ctx := context.TODO()
+
 	remainingFees := p.calcFeeBudget(ps.FeesPaid)
 
 	// Query our payment session to construct a route.
@@ -430,7 +439,9 @@ func (p *paymentLifecycle) requestRoute(
 	log.Warnf("Marking payment %v permanently failed with no route: %v",
 		p.identifier, failureCode)
 
-	err = p.router.cfg.Control.FailPayment(p.identifier, failureCode)
+	err = p.router.cfg.Control.FailPayment(
+		ctx, p.identifier, failureCode,
+	)
 	if err != nil {
 		return nil, fmt.Errorf("FailPayment got: %w", err)
 	}
@@ -800,6 +811,8 @@ func (p *paymentLifecycle) failPaymentAndAttempt(
 	attemptID uint64, reason *paymentsdb.FailureReason,
 	sendErr error) (*attemptResult, error) {
 
+	ctx := context.TODO()
+
 	log.Errorf("Payment %v failed: final_outcome=%v, raw_err=%v",
 		p.identifier, *reason, sendErr)
 
@@ -808,7 +821,9 @@ func (p *paymentLifecycle) failPaymentAndAttempt(
 	// NOTE: we must fail the payment first before failing the attempt.
 	// Otherwise, once the attempt is marked as failed, another goroutine
 	// might make another attempt while we are failing the payment.
-	err := p.router.cfg.Control.FailPayment(p.identifier, *reason)
+	err := p.router.cfg.Control.FailPayment(
+		ctx, p.identifier, *reason,
+	)
 	if err != nil {
 		log.Errorf("Unable to fail payment: %v", err)
 		return nil, err
diff --git a/routing/router.go b/routing/router.go
index 9319260..fe8d067 100644
--- a/routing/router.go
+++ b/routing/router.go
@@ -1088,7 +1088,9 @@ func (r *ChannelRouter) sendToRoute(htlcHash lntypes.Hash, rt *route.Route,
 			return nil
 		}
 
-		return r.cfg.Control.FailPayment(paymentIdentifier, reason)
+		return r.cfg.Control.FailPayment(
+			ctx, paymentIdentifier, reason,
+		)
 	}
 
 	log.Debugf("SendToRoute for payment %v with skipTempErr=%v",