highperfocused/bitcoin
1
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2026-01-21 07:39:08 +01:00
Code Issues Packages Projects Releases Wiki Activity

Merge bitcoin/bitcoin#30479: validation: Add eligible ancestors of reconsidered block to setBlockIndexCandidates

Browse Source 
8cc3ac6c23 validation: Don't use IsValid() to filter for invalid blocks (Martin Zumsande)
86d98b94e5 test: verify that ancestors of a reconsidered block can become the chain tip (stratospher)
3c39a55e64 validation: Add ancestors of reconsiderblock to setBlockIndexCandidates (Martin Zumsande)

Pull request description:

  When we call `reconsiderblock` for some block,  `Chainstate::ResetBlockFailureFlags` puts the descendants of that block into `setBlockIndexCandidates` (if they meet the criteria, i.e. have more work than the tip etc.), but never put any ancestors into the set even though we do clear their failure flags.

  I think that this is wrong, because `setBlockIndexCandidates` should always contain all eligible indexes that have at least as much work as the current tip, which can include ancestors of the reconsidered block. This is being checked by `CheckBlockIndex()`, which could fail if it was invoked after `ActivateBestChain` connects a block and releases `cs_main`:
  ``` diff
  diff --git a/src/validation.cpp b/src/validation.cpp
  index 7b04bd9a5b..ff0c3c9f58 100644
  --- a/src/validation.cpp
  +++ b/src/validation.cpp
  @@ -3551,6 +3551,7 @@ bool Chainstate::ActivateBestChain(BlockValidationState& state, std::shared_ptr<
               }
           }
           // When we reach this point, we switched to a new tip (stored in pindexNewTip).
  +        m_chainman.CheckBlockIndex();
   
           if (exited_ibd) {
               // If a background chainstate is in use, we may need to rebalance our
  ```
  makes `rpc_invalidateblock.py` fail on master.

  Even though we don't currently have a `CheckBlockIndex()` in that place, after `cs_main` is released other threads could invoke it, which is happening in the rare failures of #16444 where an invalid header received from another peer could trigger a `CheckBlockIndex()` call that would fail.

  Fix this by adding eligible ancestors to `setBlockIndexCandidates` in `Chainstate::ResetBlockFailureFlags` (also simplifying that function a bit).

  Fixes #16444

ACKs for top commit:
  achow101:
    ACK 8cc3ac6c23
  TheCharlatan:
    Re-ACK 8cc3ac6c23
  stratospher:
    reACK 8cc3ac6.

Tree-SHA512: 53f27591916246be4093d64b86a0494e55094abd8c586026b1247e4a36747bc3d6dbe46dc26ee4a22f47b8eb0d9699d13e577dee0e7198145f3c9b11ab2a30b7
This commit is contained in:
Ava Chow
2025-07-09 16:55:43 -07:00
parent 1ca62edd85 8cc3ac6c23
commit a40e953658
5 changed files with 30 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
src/validation.cpp
View File

@@ -3851,9 +3851,9 @@ void Chainstate::ResetBlockFailureFlags(CBlockIndex *pindex) {
int nHeight = pindex->nHeight;
// Remove the invalidity flag from this block and all its descendants.
// Remove the invalidity flag from this block and all its descendants and ancestors.
for (auto& [_, block_index] : m_blockman.m_block_index) {
if (!block_index.IsValid() && block_index.GetAncestor(nHeight) == pindex) {
if ((block_index.nStatus & BLOCK_FAILED_MASK) && (block_index.GetAncestor(nHeight) == pindex || pindex->GetAncestor(block_index.nHeight) == &block_index)) {
block_index.nStatus &= ~BLOCK_FAILED_MASK;
m_blockman.m_dirty_blockindex.insert(&block_index);
if (block_index.IsValid(BLOCK_VALID_TRANSACTIONS) && block_index.HaveNumChainTxs() && setBlockIndexCandidates.value_comp()(m_chain.Tip(), &block_index)) {
@@ -3865,15 +3865,6 @@ void Chainstate::ResetBlockFailureFlags(CBlockIndex *pindex) {
}
}
}
// Remove the invalidity flag from all ancestors too.
while (pindex != nullptr) {
if (pindex->nStatus & BLOCK_FAILED_MASK) {
pindex->nStatus &= ~BLOCK_FAILED_MASK;
m_blockman.m_dirty_blockindex.insert(pindex);
}
pindex = pindex->pprev;
}
}
void Chainstate::TryAddBlockIndexCandidate(CBlockIndex* pindex)