From 65d091d458ee2a621558a55fda6cda8dd0efa5f0 Mon Sep 17 00:00:00 2001
From: drklee3 <derrick@dlee.dev>
Date: Wed, 21 Aug 2024 17:29:04 -0700
Subject: [PATCH] fix(x/precisebank): Avoid blocked addr error on
 SendCoinsFromAccountToModule (#2012)

---
 x/precisebank/keeper/send.go                  | 11 +++-
 x/precisebank/keeper/send_integration_test.go | 60 +++++++++++++++++++
 2 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/x/precisebank/keeper/send.go b/x/precisebank/keeper/send.go
index 6d8c04bd..fd383419 100644
--- a/x/precisebank/keeper/send.go
+++ b/x/precisebank/keeper/send.go
@@ -179,10 +179,17 @@ func (k Keeper) sendExtendedCoins(
 	// Always send carry from reserve before receiving borrow from sender to
 	// ensure reserve always has sufficient balance starting from 0.
 	if !senderNeedsBorrow && recipientNeedsCarry {
+		reserveAddr := k.ak.GetModuleAddress(types.ModuleName)
+
+		// We use SendCoins instead of SendCoinsFromModuleToAccount to avoid
+		// the blocked addrs check. Blocked accounts should not be checked in
+		// a SendCoins operation. Only SendCoinsFromModuleToAccount should check
+		// blocked addrs which is done by the parent SendCoinsFromModuleToAccount
+		// method.
 		carryCoin := sdk.NewCoin(types.IntegerCoinDenom, sdk.NewInt(1))
-		if err := k.bk.SendCoinsFromModuleToAccount(
+		if err := k.bk.SendCoins(
 			ctx,
-			types.ModuleName,
+			reserveAddr,
 			to, // recipient carrying
 			sdk.NewCoins(carryCoin),
 		); err != nil {
diff --git a/x/precisebank/keeper/send_integration_test.go b/x/precisebank/keeper/send_integration_test.go
index 8174c76b..08c17421 100644
--- a/x/precisebank/keeper/send_integration_test.go
+++ b/x/precisebank/keeper/send_integration_test.go
@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
 	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	"github.com/kava-labs/kava/app"
@@ -622,6 +623,65 @@ func (suite *sendIntegrationTestSuite) TestSendCoinsFromAccountToModule() {
 	)
 }
 
+func (suite *sendIntegrationTestSuite) TestSendCoinsFromAccountToModule_BlockedRecipientCarry() {
+	// Carrying to module account balance. This tests that SendCoinsFromAccountToModule
+	// does not fail when sending to a blocked module account.
+
+	sender := sdk.AccAddress([]byte{1})
+
+	sendAmt := cs(c(types.ExtendedCoinDenom, 1000))
+	sendAmt2 := cs(ci(types.ExtendedCoinDenom, types.ConversionFactor().SubRaw(10)))
+
+	suite.MintToAccount(sender, sendAmt.Add(sendAmt2...))
+
+	err := suite.Keeper.SendCoinsFromAccountToModule(
+		suite.Ctx,
+		sender,
+		authtypes.FeeCollectorName,
+		sendAmt,
+	)
+	suite.Require().NoError(err)
+
+	// Trigger carry for fee_collector module account
+	err = suite.Keeper.SendCoinsFromAccountToModule(
+		suite.Ctx,
+		sender,
+		authtypes.FeeCollectorName,
+		sendAmt2,
+	)
+	suite.Require().NoError(err)
+}
+
+func (suite *sendIntegrationTestSuite) TestSendCoins_BlockedRecipientCarry() {
+	// Same test as TestSendCoinsFromModuleToAccount_Blocked, but with SendCoins
+	// which also should not fail when sending to a blocked module account.
+	sender := sdk.AccAddress([]byte{1})
+
+	sendAmt := cs(c(types.ExtendedCoinDenom, 1000))
+	sendAmt2 := cs(ci(types.ExtendedCoinDenom, types.ConversionFactor().SubRaw(10)))
+
+	suite.MintToAccount(sender, sendAmt.Add(sendAmt2...))
+
+	recipient := suite.App.GetAccountKeeper().GetModuleAddress(authtypes.FeeCollectorName)
+
+	err := suite.Keeper.SendCoins(
+		suite.Ctx,
+		sender,
+		recipient,
+		sendAmt,
+	)
+	suite.Require().NoError(err)
+
+	// Trigger carry for fee_collector module account
+	err = suite.Keeper.SendCoins(
+		suite.Ctx,
+		sender,
+		recipient,
+		sendAmt2,
+	)
+	suite.Require().NoError(err)
+}
+
 func (suite *sendIntegrationTestSuite) TestSendCoinsFromModuleToAccount() {
 	// Ensure sender correctly matches the specified module account. Opposite
 	// of SendCoinsFromAccountToModule, so we are only checking the correct