Fix data race in downloader (#1961)

palango · web-flow · commit fb462b6a037d · 2022-10-07T11:03:13.000+02:00
* chore: Fix some typos

* downloader: Fix data race when fetching headers

* downloaded: Cache extra data error as well
diff --git a/consensus/consensustest/mockprotocol.go b/consensus/consensustest/mockprotocol.go
@@ -228,7 +228,7 @@ func (e *MockEngine) VerifyHeader(chain consensus.ChainHeaderReader, header *typ
 // verifyHeader checks whether a header conforms to the consensus rules
 func (e *MockEngine) verifyHeader(chain consensus.ChainHeaderReader, header, parent *types.Header, seal bool) error {
 	// Ensure that the extra data format is satisfied
-	if _, err := types.ExtractIstanbulExtra(header); err != nil {
+	if _, err := header.IstanbulExtra(); err != nil {
 		return errors.New("invalid extra data format")
 	}
 	// Verify the header's timestamp
diff --git a/consensus/istanbul/backend/backend.go b/consensus/istanbul/backend/backend.go
@@ -476,7 +476,7 @@ func (sb *Backend) ParentBlockValidators(proposal istanbul.Proposal) istanbul.Va
 }
 
 func (sb *Backend) NextBlockValidators(proposal istanbul.Proposal) (istanbul.ValidatorSet, error) {
-	istExtra, err := types.ExtractIstanbulExtra(proposal.Header())
+	istExtra, err := proposal.Header().IstanbulExtra()
 	if err != nil {
 		return nil, err
 	}
@@ -650,7 +650,7 @@ func (sb *Backend) verifyValSetDiff(proposal istanbul.Proposal, block *types.Blo
 	header := block.Header()
 
 	// Ensure that the extra data format is satisfied
-	istExtra, err := types.ExtractIstanbulExtra(header)
+	istExtra, err := header.IstanbulExtra()
 	if err != nil {
 		return err
 	}
@@ -806,7 +806,7 @@ func (sb *Backend) GetCurrentHeadBlockAndAuthor() (istanbul.Proposal, common.Add
 
 func (sb *Backend) LastSubject() (istanbul.Subject, error) {
 	lastProposal, _ := sb.GetCurrentHeadBlockAndAuthor()
-	istExtra, err := types.ExtractIstanbulExtra(lastProposal.Header())
+	istExtra, err := lastProposal.Header().IstanbulExtra()
 	if err != nil {
 		return istanbul.Subject{}, err
 	}
diff --git a/consensus/istanbul/backend/engine.go b/consensus/istanbul/backend/engine.go
@@ -138,7 +138,7 @@ func (sb *Backend) verifyHeader(chain consensus.ChainHeaderReader, header *types
 	}
 
 	// Ensure that the extra data format is satisfied
-	if _, err := types.ExtractIstanbulExtra(header); err != nil {
+	if _, err := header.IstanbulExtra(); err != nil {
 		return errInvalidExtraDataFormat
 	}
 
@@ -273,7 +273,7 @@ func (sb *Backend) verifyAggregatedSeals(chain consensus.ChainHeaderReader, head
 		return nil
 	}
 
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		return err
 	}
@@ -373,7 +373,7 @@ func (sb *Backend) VerifySeal(header *types.Header) error {
 		return errUnknownBlock
 	}
 
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		return errInvalidExtraDataFormat
 	}
@@ -861,7 +861,7 @@ func (sb *Backend) snapshot(chain consensus.ChainHeaderReader, number uint64, ha
 			return nil, errors.New("Cannot load genesis")
 		}
 
-		istanbulExtra, err := types.ExtractIstanbulExtra(genesis)
+		istanbulExtra, err := genesis.IstanbulExtra()
 		if err != nil {
 			log.Error("Unable to extract istanbul extra", "err", err)
 			return nil, err
@@ -948,7 +948,7 @@ func (sb *Backend) addParentSeal(chain consensus.ChainHeaderReader, header *type
 
 	// Get parent's extra to fetch it's AggregatedSeal
 	parent := chain.GetHeader(header.ParentHash, number-1)
-	parentExtra, err := types.ExtractIstanbulExtra(parent)
+	parentExtra, err := parent.IstanbulExtra()
 	if err != nil {
 		return err
 	}
@@ -1046,7 +1046,7 @@ func ecrecover(header *types.Header) (common.Address, error) {
 	}
 
 	// Retrieve the signature from the header extra-data
-	istanbulExtra, err := types.ExtractIstanbulExtra(header)
+	istanbulExtra, err := header.IstanbulExtra()
 	if err != nil {
 		return common.Address{}, err
 	}
@@ -1099,7 +1099,7 @@ func writeValidatorSetDiff(header *types.Header, oldValSet []istanbul.ValidatorD
 			"addedValidators", common.ConvertToStringSlice(addedValidatorsAddresses), "removedValidators", removedValidators.Text(16))
 	}
 
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		return nil
 	}
@@ -1124,7 +1124,7 @@ func writeSeal(h *types.Header, seal []byte) error {
 		return errInvalidSignature
 	}
 
-	istanbulExtra, err := types.ExtractIstanbulExtra(h)
+	istanbulExtra, err := h.IstanbulExtra()
 	if err != nil {
 		return err
 	}
@@ -1147,7 +1147,7 @@ func writeAggregatedSeal(h *types.Header, aggregatedSeal types.IstanbulAggregate
 		return errInvalidAggregatedSeal
 	}
 
-	istanbulExtra, err := types.ExtractIstanbulExtra(h)
+	istanbulExtra, err := h.IstanbulExtra()
 	if err != nil {
 		return err
 	}
diff --git a/consensus/istanbul/backend/engine_test.go b/consensus/istanbul/backend/engine_test.go
@@ -177,7 +177,7 @@ func TestVerifySeal(t *testing.T) {
 
 	// modify seal bitmap and expect to fail the quorum check
 	header = block.Header()
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	g.Expect(err).ToNot(HaveOccurred())
 	extra.AggregatedSeal.Bitmap = big.NewInt(0)
 	encoded, err := rlp.EncodeToBytes(extra)
@@ -357,7 +357,7 @@ func TestPrepareExtra(t *testing.T) {
 	g.Expect(err).ToNot(HaveOccurred())
 
 	// the header must have the updated extra data
-	updatedExtra, err := types.ExtractIstanbulExtra(h)
+	updatedExtra, err := h.IstanbulExtra()
 	g.Expect(err).ToNot(HaveOccurred())
 
 	var updatedExtraVals []istanbul.ValidatorData
@@ -407,7 +407,7 @@ func TestWriteSeal(t *testing.T) {
 	g.Expect(err).NotTo(HaveOccurred())
 
 	// verify istanbul extra-data
-	actualIstExtra, err := types.ExtractIstanbulExtra(h)
+	actualIstExtra, err := h.IstanbulExtra()
 	g.Expect(err).NotTo(HaveOccurred())
 	g.Expect(actualIstExtra).To(Equal(expectedIstExtra))
 
@@ -457,7 +457,7 @@ func TestWriteAggregatedSeal(t *testing.T) {
 	g.Expect(err).NotTo(HaveOccurred())
 
 	// verify istanbul extra-data
-	actualIstExtra, err := types.ExtractIstanbulExtra(h)
+	actualIstExtra, err := h.IstanbulExtra()
 	g.Expect(err).NotTo(HaveOccurred())
 	g.Expect(actualIstExtra).To(Equal(expectedIstExtra))
 
diff --git a/consensus/istanbul/backend/handler.go b/consensus/istanbul/backend/handler.go
@@ -239,7 +239,7 @@ func (sb *Backend) UpdateMetricsForParentOfBlock(child *types.Block) {
 
 	// Now check if this validator signer is in the "parent seal" on the child block.
 	// The parent seal is used for downtime calculations.
-	childExtra, err := types.ExtractIstanbulExtra(child.Header())
+	childExtra, err := child.Header().IstanbulExtra()
 	if err != nil {
 		return
 	}
diff --git a/consensus/istanbul/backend/snapshot.go b/consensus/istanbul/backend/snapshot.go
@@ -130,7 +130,7 @@ func (s *Snapshot) apply(headers []*types.Header, db ethdb.Database) (*Snapshot,
 		}
 
 		// Ensure that the extra data format is satisfied
-		istExtra, err := types.ExtractIstanbulExtra(header)
+		istExtra, err := header.IstanbulExtra()
 		if err != nil {
 			log.Error("Unable to extract the istanbul extra field from the header", "header", header)
 			return nil, err
diff --git a/consensus/istanbul/uptime/monitor.go b/consensus/istanbul/uptime/monitor.go
@@ -150,7 +150,7 @@ func (um *Monitor) ProcessHeader(header *types.Header) error {
 	}
 
 	// Get the bitmap from the previous block
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		um.logger.Error("Unable to extract istanbul extra", "func", "ProcessBlock", "blocknum", headerNumber)
 		return errors.New("could not extract block header extra")
diff --git a/core/types/block.go b/core/types/block.go
@@ -23,6 +23,7 @@ import (
 	"io"
 	"math/big"
 	"reflect"
+	"sync"
 	"sync/atomic"
 	"time"
 
@@ -52,6 +53,11 @@ type Header struct {
 	GasUsed     uint64         `json:"gasUsed"          gencodec:"required"`
 	Time        uint64         `json:"timestamp"        gencodec:"required"`
 	Extra       []byte         `json:"extraData"        gencodec:"required"`
+
+	// Used to cache deserialized istanbul extra data
+	extraLock  sync.Mutex
+	extraValue *IstanbulExtra
+	extraError error
 }
 
 // field type overrides for gencodec
@@ -100,6 +106,10 @@ func (h *Header) SanityCheck() error {
 // EmptyBody returns true if there is no additional 'body' to complete the header
 // that is: no transactions.
 func (h *Header) EmptyBody() bool {
+	if _, err := h.IstanbulExtra(); err == nil {
+		return false
+	}
+
 	return h.TxHash == EmptyRootHash
 }
 
@@ -271,8 +281,19 @@ func NewBlockWithHeader(header *Header) *Block {
 // CopyHeader creates a deep copy of a block header to prevent side effects from
 // modifying a header variable.
 func CopyHeader(h *Header) *Header {
-	cpy := *h
-	if cpy.Number = new(big.Int); h.Number != nil {
+	cpy := Header{
+		ParentHash:  h.ParentHash,
+		Coinbase:    h.Coinbase,
+		Root:        h.Root,
+		TxHash:      h.TxHash,
+		ReceiptHash: h.ReceiptHash,
+		Bloom:       h.Bloom,
+		Number:      new(big.Int),
+		GasUsed:     h.GasUsed,
+		Time:        h.Time,
+	}
+
+	if h.Number != nil {
 		cpy.Number.Set(h.Number)
 	}
 	if len(h.Extra) > 0 {
@@ -366,10 +387,10 @@ func (c *writeCounter) Write(b []byte) (int, error) {
 // WithHeader returns a new block with the data from b but the header replaced with
 // the sealed one.
 func (b *Block) WithHeader(header *Header) *Block {
-	cpy := *header
+	cpy := CopyHeader(header)
 
 	return &Block{
-		header:         &cpy,
+		header:         cpy,
 		transactions:   b.transactions,
 		randomness:     b.randomness,
 		epochSnarkData: b.epochSnarkData,
diff --git a/core/types/celo_additions.go b/core/types/celo_additions.go
@@ -0,0 +1,18 @@
+package types
+
+// IstanbulExtra returns the 'Extra' field of the header deserialized into an
+// IstanbulExtra struct, if there is an error deserializing the 'Extra' field
+// it will be returned.
+func (h *Header) IstanbulExtra() (*IstanbulExtra, error) {
+	h.extraLock.Lock()
+	defer h.extraLock.Unlock()
+
+	if h.extraValue == nil && h.extraError == nil {
+		extra, err := extractIstanbulExtra(h)
+
+		h.extraValue = extra
+		h.extraError = err
+	}
+
+	return h.extraValue, h.extraError
+}
diff --git a/core/types/istanbul.go b/core/types/istanbul.go
@@ -128,7 +128,7 @@ func (ist *IstanbulExtra) DecodeRLP(s *rlp.Stream) error {
 // ExtractIstanbulExtra extracts all values of the IstanbulExtra from the header. It returns an
 // error if the length of the given extra-data is less than 32 bytes or the extra-data can not
 // be decoded.
-func ExtractIstanbulExtra(h *Header) (*IstanbulExtra, error) {
+func extractIstanbulExtra(h *Header) (*IstanbulExtra, error) {
 	if len(h.Extra) < IstanbulExtraVanity {
 		return nil, ErrInvalidIstanbulHeaderExtra
 	}
@@ -146,7 +146,7 @@ func ExtractIstanbulExtra(h *Header) (*IstanbulExtra, error) {
 // decoded/encoded by rlp.
 func IstanbulFilteredHeader(h *Header, keepSeal bool) *Header {
 	newHeader := CopyHeader(h)
-	istanbulExtra, err := ExtractIstanbulExtra(newHeader)
+	istanbulExtra, err := extractIstanbulExtra(newHeader)
 	if err != nil {
 		return nil
 	}
diff --git a/core/types/istanbul_test.go b/core/types/istanbul_test.go
@@ -82,7 +82,7 @@ func TestExtractToIstanbul(t *testing.T) {
 	for _, test := range testCases {
 		h := &Header{Extra: append(test.vanity, test.istRawData...)}
 
-		istanbulExtra, err := ExtractIstanbulExtra(h)
+		istanbulExtra, err := h.IstanbulExtra()
 		if err != test.expectedErr {
 			t.Errorf("expected: %v, but got: %v", test.expectedErr, err)
 		}
diff --git a/core/vm/contracts.go b/core/vm/contracts.go
@@ -1222,7 +1222,7 @@ func (c *getParentSealBitmap) Run(input []byte, caller common.Address, evm *EVM)
 		return nil, ErrUnexpected
 	}
 
-	extra, err := types.ExtractIstanbulExtra(header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		log.Error("Header without Istanbul extra data encountered in getParentSealBitmap precompile", "blockNumber", blockNumber, "err", err)
 		return nil, ErrEngineIncompatible
@@ -1252,7 +1252,7 @@ func (c *getVerifiedSealBitmap) Run(input []byte, caller common.Address, evm *EV
 	}
 
 	// Extract the verified seal from the header.
-	extra, err := types.ExtractIstanbulExtra(&header)
+	extra, err := header.IstanbulExtra()
 	if err != nil {
 		log.Error("Header without Istanbul extra data encountered in getVerifiedSealBitmap precompile", "extraData", header.Extra, "err", err)
 		// Seal verified by a non-Istanbul engine. Return an error.
diff --git a/eth/downloader/queue.go b/eth/downloader/queue.go
@@ -527,11 +527,6 @@ func (q *queue) reserveHeaders(p *peerConnection, count int, taskPool map[common
 			// There are no resultslots available. Leave it in the task queue
 			break
 		}
-		// Only required if the reserve is for a body type
-		if kind == bodyType {
-			// All headers must be fetched so that the random beacon can be updated correctly.
-			item.pending |= (1 << bodyType)
-		}
 		if item.Done(kind) {
 			// If it's a noop, we can skip this task
 			delete(taskPool, header.Hash())
diff --git a/eth/downloader/resultstore.go b/eth/downloader/resultstore.go
@@ -141,7 +141,7 @@ func (r *resultStore) HasCompletedItems() bool {
 // countCompleted returns the number of items ready for delivery, stopping at
 // the first non-complete item.
 //
-// The mthod assumes (at least) rlock is held.
+// The method assumes (at least) rlock is held.
 func (r *resultStore) countCompleted() int {
 	// We iterate from the already known complete point, and see
 	// if any more has completed since last count

Original file line number	Diff line number	Diff line change
`@@ -228,7 +228,7 @@ func (e MockEngine) VerifyHeader(chain consensus.ChainHeaderReader, header typ`
`228`	`228`	`// verifyHeader checks whether a header conforms to the consensus rules`
`229`	`229`	`func (e MockEngine) verifyHeader(chain consensus.ChainHeaderReader, header, parent types.Header, seal bool) error {`
`230`	`230`	`// Ensure that the extra data format is satisfied`
`231`		`- if _, err := types.ExtractIstanbulExtra(header); err != nil {`
	`231`	`+ if _, err := header.IstanbulExtra(); err != nil {`
`232`	`232`	`return errors.New("invalid extra data format")`
`233`	`233`	`}`
`234`	`234`	`// Verify the header's timestamp`
Original file line number	Diff line number	Diff line change
`@@ -476,7 +476,7 @@ func (sb *Backend) ParentBlockValidators(proposal istanbul.Proposal) istanbul.Va`
`476`	`476`	`}`
`477`	`477`
`478`	`478`	`func (sb *Backend) NextBlockValidators(proposal istanbul.Proposal) (istanbul.ValidatorSet, error) {`
`479`		`- istExtra, err := types.ExtractIstanbulExtra(proposal.Header())`
	`479`	`+ istExtra, err := proposal.Header().IstanbulExtra()`
`480`	`480`	`if err != nil {`
`481`	`481`	`return nil, err`
`482`	`482`	`}`
`@@ -650,7 +650,7 @@ func (sb Backend) verifyValSetDiff(proposal istanbul.Proposal, block types.Blo`
`650`	`650`	`header := block.Header()`
`651`	`651`
`652`	`652`	`// Ensure that the extra data format is satisfied`
`653`		`- istExtra, err := types.ExtractIstanbulExtra(header)`
	`653`	`+ istExtra, err := header.IstanbulExtra()`
`654`	`654`	`if err != nil {`
`655`	`655`	`return err`
`656`	`656`	`}`
`@@ -806,7 +806,7 @@ func (sb *Backend) GetCurrentHeadBlockAndAuthor() (istanbul.Proposal, common.Add`
`806`	`806`
`807`	`807`	`func (sb *Backend) LastSubject() (istanbul.Subject, error) {`
`808`	`808`	`lastProposal, _ := sb.GetCurrentHeadBlockAndAuthor()`
`809`		`- istExtra, err := types.ExtractIstanbulExtra(lastProposal.Header())`
	`809`	`+ istExtra, err := lastProposal.Header().IstanbulExtra()`
`810`	`810`	`if err != nil {`
`811`	`811`	`return istanbul.Subject{}, err`
`812`	`812`	`}`
Original file line number	Diff line number	Diff line change
`@@ -138,7 +138,7 @@ func (sb Backend) verifyHeader(chain consensus.ChainHeaderReader, header types`
`138`	`138`	`}`
`139`	`139`
`140`	`140`	`// Ensure that the extra data format is satisfied`
`141`		`- if _, err := types.ExtractIstanbulExtra(header); err != nil {`
	`141`	`+ if _, err := header.IstanbulExtra(); err != nil {`
`142`	`142`	`return errInvalidExtraDataFormat`
`143`	`143`	`}`
`144`	`144`
`@@ -273,7 +273,7 @@ func (sb *Backend) verifyAggregatedSeals(chain consensus.ChainHeaderReader, head`
`273`	`273`	`return nil`
`274`	`274`	`}`
`275`	`275`
`276`		`- extra, err := types.ExtractIstanbulExtra(header)`
	`276`	`+ extra, err := header.IstanbulExtra()`
`277`	`277`	`if err != nil {`
`278`	`278`	`return err`
`279`	`279`	`}`
`@@ -373,7 +373,7 @@ func (sb Backend) VerifySeal(header types.Header) error {`
`373`	`373`	`return errUnknownBlock`
`374`	`374`	`}`
`375`	`375`
`376`		`- extra, err := types.ExtractIstanbulExtra(header)`
	`376`	`+ extra, err := header.IstanbulExtra()`
`377`	`377`	`if err != nil {`
`378`	`378`	`return errInvalidExtraDataFormat`
`379`	`379`	`}`
`@@ -861,7 +861,7 @@ func (sb *Backend) snapshot(chain consensus.ChainHeaderReader, number uint64, ha`
`861`	`861`	`return nil, errors.New("Cannot load genesis")`
`862`	`862`	`}`
`863`	`863`
`864`		`- istanbulExtra, err := types.ExtractIstanbulExtra(genesis)`
	`864`	`+ istanbulExtra, err := genesis.IstanbulExtra()`
`865`	`865`	`if err != nil {`
`866`	`866`	`log.Error("Unable to extract istanbul extra", "err", err)`
`867`	`867`	`return nil, err`
`@@ -948,7 +948,7 @@ func (sb Backend) addParentSeal(chain consensus.ChainHeaderReader, header type`
`948`	`948`
`949`	`949`	`// Get parent's extra to fetch it's AggregatedSeal`
`950`	`950`	`parent := chain.GetHeader(header.ParentHash, number-1)`
`951`		`- parentExtra, err := types.ExtractIstanbulExtra(parent)`
	`951`	`+ parentExtra, err := parent.IstanbulExtra()`
`952`	`952`	`if err != nil {`
`953`	`953`	`return err`
`954`	`954`	`}`
`@@ -1046,7 +1046,7 @@ func ecrecover(header *types.Header) (common.Address, error) {`
`1046`	`1046`	`}`
`1047`	`1047`
`1048`	`1048`	`// Retrieve the signature from the header extra-data`
`1049`		`- istanbulExtra, err := types.ExtractIstanbulExtra(header)`
	`1049`	`+ istanbulExtra, err := header.IstanbulExtra()`
`1050`	`1050`	`if err != nil {`
`1051`	`1051`	`return common.Address{}, err`
`1052`	`1052`	`}`
`@@ -1099,7 +1099,7 @@ func writeValidatorSetDiff(header *types.Header, oldValSet []istanbul.ValidatorD`
`1099`	`1099`	`"addedValidators", common.ConvertToStringSlice(addedValidatorsAddresses), "removedValidators", removedValidators.Text(16))`
`1100`	`1100`	`}`
`1101`	`1101`
`1102`		`- extra, err := types.ExtractIstanbulExtra(header)`
	`1102`	`+ extra, err := header.IstanbulExtra()`
`1103`	`1103`	`if err != nil {`
`1104`	`1104`	`return nil`
`1105`	`1105`	`}`
`@@ -1124,7 +1124,7 @@ func writeSeal(h *types.Header, seal []byte) error {`
`1124`	`1124`	`return errInvalidSignature`
`1125`	`1125`	`}`
`1126`	`1126`
`1127`		`- istanbulExtra, err := types.ExtractIstanbulExtra(h)`
	`1127`	`+ istanbulExtra, err := h.IstanbulExtra()`
`1128`	`1128`	`if err != nil {`
`1129`	`1129`	`return err`
`1130`	`1130`	`}`
`@@ -1147,7 +1147,7 @@ func writeAggregatedSeal(h *types.Header, aggregatedSeal types.IstanbulAggregate`
`1147`	`1147`	`return errInvalidAggregatedSeal`
`1148`	`1148`	`}`
`1149`	`1149`
`1150`		`- istanbulExtra, err := types.ExtractIstanbulExtra(h)`
	`1150`	`+ istanbulExtra, err := h.IstanbulExtra()`
`1151`	`1151`	`if err != nil {`
`1152`	`1152`	`return err`
`1153`	`1153`	`}`
Original file line number	Diff line number	Diff line change
`@@ -239,7 +239,7 @@ func (sb Backend) UpdateMetricsForParentOfBlock(child types.Block) {`
`239`	`239`
`240`	`240`	`// Now check if this validator signer is in the "parent seal" on the child block.`
`241`	`241`	`// The parent seal is used for downtime calculations.`
`242`		`- childExtra, err := types.ExtractIstanbulExtra(child.Header())`
	`242`	`+ childExtra, err := child.Header().IstanbulExtra()`
`243`	`243`	`if err != nil {`
`244`	`244`	`return`
`245`	`245`	`}`
Original file line number	Diff line number	Diff line change
`@@ -130,7 +130,7 @@ func (s Snapshot) apply(headers []types.Header, db ethdb.Database) (*Snapshot,`
`130`	`130`	`}`
`131`	`131`
`132`	`132`	`// Ensure that the extra data format is satisfied`
`133`		`- istExtra, err := types.ExtractIstanbulExtra(header)`
	`133`	`+ istExtra, err := header.IstanbulExtra()`
`134`	`134`	`if err != nil {`
`135`	`135`	`log.Error("Unable to extract the istanbul extra field from the header", "header", header)`
`136`	`136`	`return nil, err`
Original file line number	Diff line number	Diff line change
`@@ -150,7 +150,7 @@ func (um Monitor) ProcessHeader(header types.Header) error {`
`150`	`150`	`}`
`151`	`151`
`152`	`152`	`// Get the bitmap from the previous block`
`153`		`- extra, err := types.ExtractIstanbulExtra(header)`
	`153`	`+ extra, err := header.IstanbulExtra()`
`154`	`154`	`if err != nil {`
`155`	`155`	`um.logger.Error("Unable to extract istanbul extra", "func", "ProcessBlock", "blocknum", headerNumber)`
`156`	`156`	`return errors.New("could not extract block header extra")`