eth/protocols/snap: fix the flaws in the snap sync

eth/protocols/snap/sync.go

@@ -1553,6 +1553,12 @@ func (s *Syncer) processAccountResponse(res *accountResponse) {
  // Ensure that the response doesn't overflow into the subsequent task
  last := res.task.Last.Big()
  for i, hash := range res.hashes {
+ // Mark the range complete if the last is already included.
+ // Keep iteration to delete the extra states if exists.
+ if hash.Big().Cmp(last) == 0 {
+ res.cont = false
+ continue
+ }
  if hash.Big().Cmp(last) > 0 {
  // Chunk overflown, cut off excess, but also update the boundary nodes
  for j := i; j < len(res.hashes); j++ {
@@ -1761,6 +1767,12 @@ func (s *Syncer) processStorageResponse(res *storageResponse) {
  // Ensure the response doesn't overflow into the subsequent task
  last := res.subTask.Last.Big()
  for k, hash := range res.hashes[i] {
+ // Mark the range complete if the last is already included.
+ // Keep iteration to delete the extra states if exists.
+ if hash.Big().Cmp(last) == 0 {
+ res.cont = false
+ continue
+ }
  if hash.Big().Cmp(last) > 0 {
  // Chunk overflown, cut off excess, but also update the boundary
  for l := k; l < len(res.hashes[i]); l++ {
@@ -1793,6 +1805,10 @@ func (s *Syncer) processStorageResponse(res *storageResponse) {
  skipped++
  continue
  }
+ if _, err := res.overflow.Get(it.Key()); err == nil {
+ skipped++
+ continue
+ }
  }
  // Node is not a boundary, persist to disk
  batch.Put(it.Key(), it.Value())