Merge pull request #17839 from karalabe/downloader-invalid-hash-chain-fix

eth/downloader: fix invalid hash chain error due to head mini reorg
This commit is contained in:
Péter Szilágyi 2018-10-05 11:03:38 +03:00 committed by GitHub
commit 5d3b7bb023
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 40 additions and 3 deletions

@ -60,6 +60,9 @@ var (
maxHeadersProcess = 2048 // Number of header download results to import at once into the chain
maxResultsProcess = 2048 // Number of content download results to import at once into the chain
reorgProtThreshold = 48 // Threshold number of recent blocks to disable mini reorg protection
reorgProtHeaderDelay = 2 // Number of headers to delay delivering to cover mini reorgs
fsHeaderCheckFrequency = 100 // Verification frequency of the downloaded headers during fast sync
fsHeaderSafetyNet = 2048 // Number of headers to discard in case a chain violation is detected
fsHeaderForceVerify = 24 // Number of headers to verify before and after the pivot to accept it
@ -847,6 +850,30 @@ func (d *Downloader) fetchHeaders(p *peerConnection, from uint64, pivot uint64)
}
headers = filled[proced:]
from += uint64(proced)
} else {
// If we're closing in on the chain head, but haven't yet reached it, delay
// the last few headers so mini reorgs on the head don't cause invalid hash
// chain errors.
if n := len(headers); n > 0 {
// Retrieve the current head we're at
head := uint64(0)
if d.mode == LightSync {
head = d.lightchain.CurrentHeader().Number.Uint64()
} else {
head = d.blockchain.CurrentFastBlock().NumberU64()
if full := d.blockchain.CurrentBlock().NumberU64(); head < full {
head = full
}
}
// If the head is way older than this batch, delay the last few headers
if head+uint64(reorgProtThreshold) < headers[n-1].Number.Uint64() {
delay := reorgProtHeaderDelay
if delay > n {
delay = n
}
headers = headers[:n-delay]
}
}
}
// Insert all the new headers and fetch the next batch
if len(headers) > 0 {
@ -857,8 +884,18 @@ func (d *Downloader) fetchHeaders(p *peerConnection, from uint64, pivot uint64)
return errCancelHeaderFetch
}
from += uint64(len(headers))
getHeaders(from)
} else {
// No headers delivered, or all of them being delayed, sleep a bit and retry
p.log.Trace("All headers delayed, waiting")
select {
case <-time.After(fsHeaderContCheck):
getHeaders(from)
continue
case <-d.cancelCh:
return errCancelHeaderFetch
}
}
getHeaders(from)
case <-timeout.C:
if d.dropPeer == nil {

@ -744,7 +744,7 @@ func testThrottling(t *testing.T, protocol int, mode SyncMode) {
tester.downloader.queue.lock.Unlock()
tester.lock.Unlock()
if cached == blockCacheItems || retrieved+cached+frozen == targetBlocks+1 {
if cached == blockCacheItems || cached == blockCacheItems-reorgProtHeaderDelay || retrieved+cached+frozen == targetBlocks+1 || retrieved+cached+frozen == targetBlocks+1-reorgProtHeaderDelay {
break
}
}
@ -754,7 +754,7 @@ func testThrottling(t *testing.T, protocol int, mode SyncMode) {
tester.lock.RLock()
retrieved = len(tester.ownBlocks)
tester.lock.RUnlock()
if cached != blockCacheItems && retrieved+cached+frozen != targetBlocks+1 {
if cached != blockCacheItems && cached != blockCacheItems-reorgProtHeaderDelay && retrieved+cached+frozen != targetBlocks+1 && retrieved+cached+frozen != targetBlocks+1-reorgProtHeaderDelay {
t.Fatalf("block count mismatch: have %v, want %v (owned %v, blocked %v, target %v)", cached, blockCacheItems, retrieved, frozen, targetBlocks+1)
}
// Permit the blocked blocks to import