From 4bf6b521580e9fbe8c2e0d16b1df953a3752c3d1 Mon Sep 17 00:00:00 2001
From: Andras Banki-Horvath <bhandras@gmail.com>
Date: Tue, 17 Oct 2023 15:42:02 +0200
Subject: [PATCH] channeldb: fetch the invoice before calling into
 updateInvoice

---
 channeldb/invoices.go | 53 +++++++++++++++++++++++--------------------
 1 file changed, 28 insertions(+), 25 deletions(-)

diff --git a/channeldb/invoices.go b/channeldb/invoices.go
index 9793b2c85..5c3891cd7 100644
--- a/channeldb/invoices.go
+++ b/channeldb/invoices.go
@@ -641,10 +641,25 @@ func (d *DB) UpdateInvoice(_ context.Context, ref invpkg.InvoiceRef,
 			return err
 		}
 
+		// If the set ID hint is non-nil, then we'll use that to filter
+		// out the HTLCs for AMP invoice so we don't need to read them
+		// all out to satisfy the invoice callback below. If it's nil,
+		// then we pass in the zero set ID which means no HTLCs will be
+		// read out.
+		var invSetID invpkg.SetID
+
+		if setIDHint != nil {
+			invSetID = *setIDHint
+		}
+		invoice, err := fetchInvoice(invoiceNum, invoices, &invSetID)
+		if err != nil {
+			return err
+		}
+
 		payHash := ref.PayHash()
 		updatedInvoice, err = d.updateInvoice(
-			payHash, setIDHint, invoices, settleIndex, setIDIndex,
-			invoiceNum, callback,
+			payHash, invoices, settleIndex, setIDIndex,
+			&invoice, invoiceNum, callback,
 		)
 
 		return err
@@ -1872,26 +1887,14 @@ func settleHtlcsAmp(invoice *invpkg.Invoice,
 
 // updateInvoice fetches the invoice, obtains the update descriptor from the
 // callback and applies the updates in a single db transaction.
-func (d *DB) updateInvoice(hash *lntypes.Hash, refSetID *invpkg.SetID, invoices,
-	settleIndex, setIDIndex kvdb.RwBucket, invoiceNum []byte,
-	callback invpkg.InvoiceUpdateCallback) (*invpkg.Invoice, error) {
-
-	// If the set ID is non-nil, then we'll use that to filter out the
-	// HTLCs for AMP invoice so we don't need to read them all out to
-	// satisfy the invoice callback below. If it's nil, then we pass in the
-	// zero set ID which means no HTLCs will be read out.
-	var invSetID invpkg.SetID
-	if refSetID != nil {
-		invSetID = *refSetID
-	}
-	invoice, err := fetchInvoice(invoiceNum, invoices, &invSetID)
-	if err != nil {
-		return nil, err
-	}
+func (d *DB) updateInvoice(hash *lntypes.Hash, invoices,
+	settleIndex, setIDIndex kvdb.RwBucket, invoice *invpkg.Invoice,
+	invoiceNum []byte, callback invpkg.InvoiceUpdateCallback) (
+	*invpkg.Invoice, error) {
 
 	// Create deep copy to prevent any accidental modification in the
 	// callback.
-	invoiceCopy, err := invpkg.CopyInvoice(&invoice)
+	invoiceCopy, err := invpkg.CopyInvoice(invoice)
 	if err != nil {
 		return nil, err
 	}
@@ -1899,33 +1902,33 @@ func (d *DB) updateInvoice(hash *lntypes.Hash, refSetID *invpkg.SetID, invoices,
 	// Call the callback and obtain the update descriptor.
 	update, err := callback(invoiceCopy)
 	if err != nil {
-		return &invoice, err
+		return invoice, err
 	}
 
 	// If there is nothing to update, return early.
 	if update == nil {
-		return &invoice, nil
+		return invoice, nil
 	}
 
 	switch update.UpdateType {
 	case invpkg.CancelHTLCsUpdate:
-		return d.cancelHTLCs(invoices, invoiceNum, &invoice, update)
+		return d.cancelHTLCs(invoices, invoiceNum, invoice, update)
 
 	case invpkg.AddHTLCsUpdate:
 		return d.addHTLCs(
-			invoices, settleIndex, setIDIndex, invoiceNum, &invoice,
+			invoices, settleIndex, setIDIndex, invoiceNum, invoice,
 			hash, update,
 		)
 
 	case invpkg.SettleHodlInvoiceUpdate:
 		return d.settleHodlInvoice(
-			invoices, settleIndex, invoiceNum, &invoice, hash,
+			invoices, settleIndex, invoiceNum, invoice, hash,
 			update.State,
 		)
 
 	case invpkg.CancelInvoiceUpdate:
 		return d.cancelInvoice(
-			invoices, invoiceNum, &invoice, hash, update.State,
+			invoices, invoiceNum, invoice, hash, update.State,
 		)
 
 	default: