From 60e6274d0fdaeb86da4521f7ee8b8b2178a845b5 Mon Sep 17 00:00:00 2001
From: "mergify[bot]" <37929162+mergify[bot]@users.noreply.github.com>
Date: Wed, 24 Aug 2022 16:45:44 +0200
Subject: [PATCH] feat: Change the default priority mechanism to be based on
 gas price (backport #12953) (#13006)

* feat: Change the default priority mechanism to be based on gas price (#12953)

(cherry picked from commit befd8162ee25bec8e231b52d3646430c61c3dafc)

# Conflicts:
#	CHANGELOG.md
#	x/auth/ante/fee_test.go

* fix conflict

Co-authored-by: yihuang <huang@crypto.com>
Co-authored-by: Julien Robert <julien@rbrt.fr>
---
 CHANGELOG.md                    |  1 +
 x/auth/ante/fee_test.go         | 10 +++++-----
 x/auth/ante/validator_tx_fee.go | 13 ++++++++-----
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ecdf8a1c4f39..846712e58dd5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -39,6 +39,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Improvements
 
+* [#12953](https://github.com/cosmos/cosmos-sdk/pull/12953) Change the default priority mechanism to be based on gas price.
 * [#12981](https://github.com/cosmos/cosmos-sdk/pull/12981) Return proper error when parsing telemetry configuration.
 * [#12969](https://github.com/cosmos/cosmos-sdk/pull/12969) Bump Tendermint to `v0.34.21` and IAVL to `v0.19.1`.
 * [#12886](https://github.com/cosmos/cosmos-sdk/pull/12886) Amortize cost of processing cache KV store.
diff --git a/x/auth/ante/fee_test.go b/x/auth/ante/fee_test.go
index a182b4fa15b1..c63706137e0a 100644
--- a/x/auth/ante/fee_test.go
+++ b/x/auth/ante/fee_test.go
@@ -57,7 +57,7 @@ func (s *AnteTestSuite) TestEnsureMempoolFees() {
 	// msg and signatures
 	msg := testdata.NewTestMsg(addr1)
 	feeAmount := testdata.NewTestFeeAmount()
-	gasLimit := testdata.NewTestGasLimit()
+	gasLimit := uint64(15)
 	s.Require().NoError(s.txBuilder.SetMsgs(msg))
 	s.txBuilder.SetFeeAmount(feeAmount)
 	s.txBuilder.SetGasLimit(gasLimit)
@@ -67,7 +67,7 @@ func (s *AnteTestSuite) TestEnsureMempoolFees() {
 	s.Require().NoError(err)
 
 	// Set high gas price so standard test fee fails
-	atomPrice := sdk.NewDecCoinFromDec("atom", sdk.NewDec(200).Quo(sdk.NewDec(100000)))
+	atomPrice := sdk.NewDecCoinFromDec("atom", sdk.NewDec(20))
 	highGasPrice := []sdk.DecCoin{atomPrice}
 	s.ctx = s.ctx.WithMinGasPrices(highGasPrice)
 
@@ -99,9 +99,9 @@ func (s *AnteTestSuite) TestEnsureMempoolFees() {
 
 	newCtx, err := antehandler(s.ctx, tx, false)
 	s.Require().Nil(err, "Decorator should not have errored on fee higher than local gasPrice")
-	// Priority is the smallest amount in any denom. Since we have only 1 fee
-	// of 150atom, the priority here is 150.
-	s.Require().Equal(feeAmount.AmountOf("atom").Int64(), newCtx.Priority())
+	// Priority is the smallest gas price amount in any denom. Since we have only 1 gas price
+	// of 10atom, the priority here is 10.
+	s.Require().Equal(int64(10), newCtx.Priority())
 }
 
 func (s *AnteTestSuite) TestDeductFees() {
diff --git a/x/auth/ante/validator_tx_fee.go b/x/auth/ante/validator_tx_fee.go
index b1725d62ddc0..dbb13988806b 100644
--- a/x/auth/ante/validator_tx_fee.go
+++ b/x/auth/ante/validator_tx_fee.go
@@ -40,18 +40,21 @@ func checkTxFeeWithValidatorMinGasPrices(ctx sdk.Context, tx sdk.Tx) (sdk.Coins,
 		}
 	}
 
-	priority := getTxPriority(feeCoins)
+	priority := getTxPriority(feeCoins, int64(gas))
 	return feeCoins, priority, nil
 }
 
-// getTxPriority returns a naive tx priority based on the amount of the smallest denomination of the fee
+// getTxPriority returns a naive tx priority based on the amount of the smallest denomination of the gas price
 // provided in a transaction.
-func getTxPriority(fee sdk.Coins) int64 {
+// NOTE: This implementation should be used with a great consideration as it opens potential attack vectors
+// where txs with multiple coins could not be prioritize as expected.
+func getTxPriority(fee sdk.Coins, gas int64) int64 {
 	var priority int64
 	for _, c := range fee {
 		p := int64(math.MaxInt64)
-		if c.Amount.IsInt64() {
-			p = c.Amount.Int64()
+		gasPrice := c.Amount.QuoRaw(gas)
+		if gasPrice.IsInt64() {
+			p = gasPrice.Int64()
 		}
 		if priority == 0 || p < priority {
 			priority = p