diff --git a/checks.go b/checks.go
index e6ee9f7e8..a14099c12 100644
--- a/checks.go
+++ b/checks.go
@@ -10,7 +10,7 @@ import (
 	"github.com/filecoin-project/lotus/chain/types"
 )
 
-func checkPieces(ctx context.Context, si *SectorInfo, api sealingApi) error {
+func checkPieces(ctx context.Context, si SectorInfo, api sealingApi) error {
 	for i, piece := range si.Pieces {
 		deal, err := api.StateMarketStorageDeal(ctx, piece.DealID, nil)
 		if err != nil {
@@ -29,7 +29,7 @@ func checkPieces(ctx context.Context, si *SectorInfo, api sealingApi) error {
 	return nil
 }
 
-func checkSeal(ctx context.Context, maddr address.Address, si *SectorInfo, api sealingApi) (err error) {
+func checkSeal(ctx context.Context, maddr address.Address, si SectorInfo, api sealingApi) (err error) {
 	ssize, err := api.StateMinerSectorSize(ctx, maddr, nil)
 	if err != nil {
 		return err
@@ -45,7 +45,7 @@ func checkSeal(ctx context.Context, maddr address.Address, si *SectorInfo, api s
 
 	ccmt := &types.Message{
 		To:       actors.StorageMarketAddress,
-		From:     actors.StorageMarketAddress,
+		From:     maddr,
 		Value:    types.NewInt(0),
 		GasPrice: types.NewInt(0),
 		GasLimit: types.NewInt(9999999999),
@@ -57,7 +57,7 @@ func checkSeal(ctx context.Context, maddr address.Address, si *SectorInfo, api s
 		return xerrors.Errorf("calling ComputeDataCommitment: %w", err)
 	}
 	if r.ExitCode != 0 {
-		return xerrors.Errorf("receipt for ComputeDataCommitment han exit code %d", r.ExitCode)
+		return xerrors.Errorf("receipt for ComputeDataCommitment had exit code %d", r.ExitCode)
 	}
 	if string(r.Return) != string(si.CommD) {
 		return xerrors.Errorf("on chain CommD differs from sector: %x != %x", r.Return, si.CommD)
diff --git a/fsm.go b/fsm.go
index ce4e74408..ba2702696 100644
--- a/fsm.go
+++ b/fsm.go
@@ -34,8 +34,10 @@ var fsmPlanners = []func(events []statemachine.Event, state *SectorInfo) error{
 	api.Unsealed: planOne(
 		on(SectorSealed{}, api.PreCommitting),
 		on(SectorSealFailed{}, api.SealFailed),
+		on(SectorPackingFailed{}, api.PackingFailed),
 	),
 	api.PreCommitting: planOne(
+		on(SectorSealFailed{}, api.SealFailed),
 		on(SectorPreCommitted{}, api.WaitSeed),
 		on(SectorPreCommitFailed{}, api.PreCommitFailed),
 	),
@@ -221,7 +223,7 @@ func planOne(ts ...func() (mut mutator, next api.SectorState)) func(events []sta
 	return func(events []statemachine.Event, state *SectorInfo) error {
 		if len(events) != 1 {
 			for _, event := range events {
-				if gm, ok := event.User.(globalMutator); !ok {
+				if gm, ok := event.User.(globalMutator); ok {
 					gm.applyGlobal(state)
 					return nil
 				}
@@ -229,7 +231,7 @@ func planOne(ts ...func() (mut mutator, next api.SectorState)) func(events []sta
 			return xerrors.Errorf("planner for state %s only has a plan for a single event only, got %+v", api.SectorStates[state.State], events)
 		}
 
-		if gm, ok := events[0].User.(globalMutator); !ok {
+		if gm, ok := events[0].User.(globalMutator); ok {
 			gm.applyGlobal(state)
 			return nil
 		}
diff --git a/fsm_events.go b/fsm_events.go
index 12c47f046..d25668da2 100644
--- a/fsm_events.go
+++ b/fsm_events.go
@@ -60,6 +60,10 @@ func (evt SectorPacked) apply(state *SectorInfo) {
 	state.Pieces = append(state.Pieces, evt.pieces...)
 }
 
+type SectorPackingFailed struct{ error }
+
+func (evt SectorPackingFailed) apply(*SectorInfo) {}
+
 type SectorSealed struct {
 	commR  []byte
 	commD  []byte
diff --git a/states.go b/states.go
index ad4a8f542..219e26475 100644
--- a/states.go
+++ b/states.go
@@ -44,6 +44,10 @@ func (m *Sealing) handlePacking(ctx statemachine.Context, sector SectorInfo) err
 }
 
 func (m *Sealing) handleUnsealed(ctx statemachine.Context, sector SectorInfo) error {
+	if err := checkPieces(ctx.Context(), sector, m.api); err != nil { // Sanity check state
+		return ctx.Send(SectorPackingFailed{xerrors.Errorf("checkPieces error: %w", err)})
+	}
+
 	log.Infow("performing sector replication...", "sector", sector.SectorID)
 	ticket, err := m.tktFn(ctx.Context())
 	if err != nil {
@@ -66,6 +70,10 @@ func (m *Sealing) handleUnsealed(ctx statemachine.Context, sector SectorInfo) er
 }
 
 func (m *Sealing) handlePreCommitting(ctx statemachine.Context, sector SectorInfo) error {
+	if err := checkSeal(ctx.Context(), m.maddr, sector, m.api); err != nil {
+		return ctx.Send(SectorSealFailed{xerrors.Errorf("checkPieces error: %w", err)})
+	}
+
 	params := &actors.SectorPreCommitInfo{
 		SectorNumber: sector.SectorID,