core: fix crash in chain reimport (#19986)

* blockchain: fix flaw in block import

* core/blockchain: address review concerns

* core/blockchain: go format with 's'
This commit is contained in:
Martin Holst Swende 2019-08-21 09:17:19 +02:00 committed by Péter Szilágyi
parent 039a9c3622
commit 4aee0d1994
2 changed files with 51 additions and 0 deletions

View File

@ -1742,6 +1742,11 @@ func (bc *BlockChain) insertSideChain(block *types.Block, it *insertIterator) (i
canonical := bc.GetBlockByNumber(number)
if canonical != nil && canonical.Hash() == block.Hash() {
// Not a sidechain block, this is a re-import of a canon block which has it's state pruned
// Collect the TD of the block. Since we know it's a canon one,
// we can get it directly, and not (like further below) use
// the parent and then add the block on top
externTd = bc.GetTd(block.Hash(), block.NumberU64())
continue
}
if canonical != nil && canonical.Root() == block.Root() {

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@ -2241,3 +2241,49 @@ func BenchmarkBlockChain_1x1000Executions(b *testing.B) {
}
benchmarkLargeNumberOfValueToNonexisting(b, numTxs, numBlocks, recipientFn, dataFn)
}
// Tests that importing a some old blocks, where all blocks are before the
// pruning point.
// This internally leads to a sidechain import, since the blocks trigger an
// ErrPrunedAncestor error.
// This may e.g. happen if
// 1. Downloader rollbacks a batch of inserted blocks and exits
// 2. Downloader starts to sync again
// 3. The blocks fetched are all known and canonical blocks
func TestSideImportPrunedBlocks(t *testing.T) {
// Generate a canonical chain to act as the main dataset
engine := ethash.NewFaker()
db := rawdb.NewMemoryDatabase()
genesis := new(Genesis).MustCommit(db)
// Generate and import the canonical chain
blocks, _ := GenerateChain(params.TestChainConfig, genesis, engine, db, 2*TriesInMemory, nil)
diskdb := rawdb.NewMemoryDatabase()
new(Genesis).MustCommit(diskdb)
chain, err := NewBlockChain(diskdb, nil, params.TestChainConfig, engine, vm.Config{}, nil)
if err != nil {
t.Fatalf("failed to create tester chain: %v", err)
}
if n, err := chain.InsertChain(blocks); err != nil {
t.Fatalf("block %d: failed to insert into chain: %v", n, err)
}
lastPrunedIndex := len(blocks) - TriesInMemory - 1
lastPrunedBlock := blocks[lastPrunedIndex]
// Verify pruning of lastPrunedBlock
if chain.HasBlockAndState(lastPrunedBlock.Hash(), lastPrunedBlock.NumberU64()) {
t.Errorf("Block %d not pruned", lastPrunedBlock.NumberU64())
}
firstNonPrunedBlock := blocks[len(blocks)-TriesInMemory]
// Verify firstNonPrunedBlock is not pruned
if !chain.HasBlockAndState(firstNonPrunedBlock.Hash(), firstNonPrunedBlock.NumberU64()) {
t.Errorf("Block %d pruned", firstNonPrunedBlock.NumberU64())
}
// Now re-import some old blocks
blockToReimport := blocks[5:8]
_, err = chain.InsertChain(blockToReimport)
if err != nil {
t.Errorf("Got error, %v", err)
}
}