fix: use initialHeight correctly

CHANGELOG.md

@@ -173,6 +173,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Bug Fixes
 
+* (baseapp) [#15789](https://github.com/cosmos/cosmos-sdk/pull/15789) Ensure `PrepareProposal` and `ProcessProposal` respect `InitialHeight` set by CometBFT when set to a value greater than 1.
 * (types) [#15691](https://github.com/cosmos/cosmos-sdk/pull/15691) Make Coin.Validate() check that .Amount is not nil
 * (types) [#15433](https://github.com/cosmos/cosmos-sdk/pull/15433) Allow disabling of account address caches (for printing bech32 account addresses).
 * (x/auth) [#15059](https://github.com/cosmos/cosmos-sdk/pull/15059) `ante.CountSubKeys` returns 0 when passing a nil `Pubkey`.

baseapp/abci.go

@@ -48,13 +48,14 @@ func (app *BaseApp) InitChain(req abci.RequestInitChain) (res abci.ResponseInitC
 
 	app.logger.Info("InitChain", "initialHeight", req.InitialHeight, "chainID", req.ChainId)
 
-	// If req.InitialHeight is > 1, then we set the initial version in the
-	// stores.
+	// Set the initial height, which will be used to determine if we are proposing
+	// or processing the first block or not.
+	app.initialHeight = req.InitialHeight
+
+	// if req.InitialHeight is > 1, then we set the initial version on all stores
 	if req.InitialHeight > 1 {
-		app.initialHeight = req.InitialHeight
-		initHeader = cmtproto.Header{ChainID: req.ChainId, Height: req.InitialHeight, Time: req.Time}
-		err := app.cms.SetInitialVersion(req.InitialHeight)
-		if err != nil {
+		initHeader.Height = req.InitialHeight
+		if err := app.cms.SetInitialVersion(req.InitialHeight); err != nil {
 			panic(err)
 		}
 	}
@@ -1017,11 +1018,13 @@ func SplitABCIQueryPath(requestPath string) (path []string) {
 // ProcessProposal. We use deliverState on the first block to be able to access
 // any state changes made in InitChain.
 func (app *BaseApp) getContextForProposal(ctx sdk.Context, height int64) sdk.Context {
-	if height == 1 {
+	if height == app.initialHeight {
 		ctx, _ = app.deliverState.ctx.CacheContext()
+
 		// clear all context data set during InitChain to avoid inconsistent behavior
 		ctx = ctx.WithBlockHeader(cmtproto.Header{})
 		return ctx
 	}
+
 	return ctx
 }

baseapp/abci_test.go

@@ -1407,6 +1407,7 @@ func TestABCI_Proposal_Read_State_PrepareProposal(t *testing.T) {
 	suite := NewBaseAppSuite(t, setInitChainerOpt, prepareOpt)
 
 	suite.baseApp.InitChain(abci.RequestInitChain{
+		InitialHeight:   1,
 		ConsensusParams: &cmtproto.ConsensusParams{},
 	})
 

baseapp/baseapp.go

@@ -493,19 +493,21 @@ func (app *BaseApp) validateHeight(req abci.RequestBeginBlock) error {
 		return fmt.Errorf("invalid height: %d", req.Header.Height)
 	}
 
-	// expectedHeight holds the expected height to validate.
+	lastBlockHeight := app.LastBlockHeight()
+
+	// expectedHeight holds the expected height to validate
 	var expectedHeight int64
-	if app.LastBlockHeight() == 0 && app.initialHeight > 1 {
-		// In this case, we're validating the first block of the chain (no
-		// previous commit). The height we're expecting is the initial height.
+	if lastBlockHeight == 0 && app.initialHeight > 1 {
+		// In this case, we're validating the first block of the chain, i.e no
+		// previous commit. The height we're expecting is the initial height.
 		expectedHeight = app.initialHeight
 	} else {
 		// This case can mean two things:
-		// - either there was already a previous commit in the store, in which
-		// case we increment the version from there,
-		// - or there was no previous commit, and initial version was not set,
-		// in which case we start at version 1.
-		expectedHeight = app.LastBlockHeight() + 1
+		//
+		// - Either there was already a previous commit in the store, in which
+		// case we increment the version from there.
+		// - Or there was no previous commit, in which case we start at version 1.
+		expectedHeight = lastBlockHeight + 1
 	}
 
 	if req.Header.Height != expectedHeight {