feat: increase gas cost for submit proposal

CHANGELOG.md

@@ -99,6 +99,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * [\#9879](https://github.com/cosmos/cosmos-sdk/pull/9879) Modify ABCI Queries to use `abci.QueryRequest` Height field if it is non-zero, otherwise continue using context height.
 * [\#9594](https://github.com/cosmos/cosmos-sdk/pull/9594) Remove legacy REST API. Please see the [REST Endpoints Migration guide](https://docs.cosmos.network/master/migrations/rest.html) to migrate to the new REST endpoints.
+* [\#9995](https://github.com/cosmos/cosmos-sdk/pull/9995) Increased gas cost for creating proposals.
 
 ### CLI Breaking Changes
 

x/gov/abci_test.go

@@ -39,8 +39,7 @@ func TestTickExpiredDepositPeriod(t *testing.T) {
 	)
 	require.NoError(t, err)
 
-	wrapCtx := sdk.WrapSDKContext(ctx)
-	res, err := govMsgSvr.SubmitProposal(wrapCtx, newProposalMsg)
+	res, err := govMsgSvr.SubmitProposal(sdk.WrapSDKContext(ctx), newProposalMsg)
 	require.NoError(t, err)
 	require.NotNil(t, res)
 

x/gov/keeper/msg_server.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/armon/go-metrics"
 
+	store "github.com/cosmos/cosmos-sdk/store/types"
 	"github.com/cosmos/cosmos-sdk/telemetry"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/x/gov/types"
@@ -31,6 +32,17 @@ func (k msgServer) SubmitProposal(goCtx context.Context, msg *types.MsgSubmitPro
 		return nil, err
 	}
 
+	bytes, err := proposal.Marshal()
+	if err != nil {
+		return nil, err
+	}
+
+	// ref: https://github.com/cosmos/cosmos-sdk/issues/9683
+	ctx.GasMeter().ConsumeGas(
+		3*store.KVGasConfig().WriteCostPerByte*uint64(len(bytes)),
+		"submit proposal",
+	)
+
 	defer telemetry.IncrCounter(1, types.ModuleName, "proposal")
 
 	votingStarted, err := k.Keeper.AddDeposit(ctx, proposal.ProposalId, msg.GetProposer(), msg.GetInitialDeposit())