validation: don't update BLOCK_FAILED_VALID to BLOCK_FAILED_CHILD in InvalidateBlock
What the developer wrote
Authored by stratospher
validation: don't update BLOCK_FAILED_VALID to BLOCK_FAILED_CHILD in InvalidateBlock
- there is no functional difference between BLOCK_FAILED_VALID and BLOCK_FAILED_CHILD
and it's unnecessary code complexity to correctly categorise them.
What changed, and why it matters
This commit simplifies how Bitcoin Core marks blocks as invalid. Previously, the code tried to distinguish between a block that failed validation itself and a child of a failed block, using two different status flags. The commit removes that distinction and uses one flag for both cases, because the two statuses were functionally equivalent. It is a code-cleanup change with no apparent security impact.
No security action required. Treat as routine refactoring. Reviewers may optionally verify that downstream consumers of nStatus treat BLOCK_FAILED_VALID and BLOCK_FAILED_CHILD equivalently, as the commit message asserts.
Security signals we found
No security relevance claimed by vendor
Change is described as non-functional cleanup
No validation logic, consensus rules, or cryptographic checks modified
Only block status flag bookkeeping simplified
Evidence from the diff
In Chainstate::InvalidateBlock, the code previously converted BLOCK_FAILED_VALID to BLOCK_FAILED_CHILD for the last disconnected block and for out-of-chain descendants. This commit removes the conversion logic and marks all such blocks with BLOCK_FAILED_VALID instead. The commit message explicitly states there is no functional difference between BLOCK_FAILED_VALID and BLOCK_FAILED_CHILD and that the change reduces unnecessary complexity. The patch removes 12 lines and adds 3 lines in src/validation.cpp.
Changed components
src/validation.cppChainstate::InvalidateBlockblock status flag managementInspect captured patch +3 / −12
diff --git a/src/validation.cpp b/src/validation.cpp
index c200c3d6..ab55e591 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3637,15 +3637,8 @@ bool Chainstate::InvalidateBlock(BlockValidationState& state, CBlockIndex* pinde
m_blockman.m_dirty_blockindex.insert(invalid_walk_tip);
setBlockIndexCandidates.erase(invalid_walk_tip);
setBlockIndexCandidates.insert(invalid_walk_tip->pprev);
- if (invalid_walk_tip == to_mark_failed->pprev && (to_mark_failed->nStatus & BLOCK_FAILED_VALID)) {
- // We only want to mark the last disconnected block as BLOCK_FAILED_VALID; its children
- // need to be BLOCK_FAILED_CHILD instead.
- to_mark_failed->nStatus = (to_mark_failed->nStatus ^ BLOCK_FAILED_VALID) | BLOCK_FAILED_CHILD;
- m_blockman.m_dirty_blockindex.insert(to_mark_failed);
- }
// Mark out-of-chain descendants of the invalidated block as invalid
- // (possibly replacing a pre-existing BLOCK_FAILED_VALID with BLOCK_FAILED_CHILD)
// Add any equal or more work headers that are not invalidated to setBlockIndexCandidates
// Recalculate m_best_header if it became invalid.
auto candidate_it = highpow_outofchain_headers.lower_bound(invalid_walk_tip->pprev->nChainWork);
@@ -3659,9 +3652,8 @@ bool Chainstate::InvalidateBlock(BlockValidationState& state, CBlockIndex* pinde
while (candidate_it != highpow_outofchain_headers.end()) {
CBlockIndex* candidate{candidate_it->second};
if (candidate->GetAncestor(invalid_walk_tip->nHeight) == invalid_walk_tip) {
- // Children of failed blocks should be marked as BLOCK_FAILED_CHILD instead.
- candidate->nStatus &= ~BLOCK_FAILED_VALID;
- candidate->nStatus |= BLOCK_FAILED_CHILD;
+ // Children of failed blocks are marked as BLOCK_FAILED_VALID.
+ candidate->nStatus |= BLOCK_FAILED_VALID;
m_blockman.m_dirty_blockindex.insert(candidate);
// If invalidated, the block is irrelevant for setBlockIndexCandidates
// and for m_best_header and can be removed from the cache.
@@ -3682,8 +3674,7 @@ bool Chainstate::InvalidateBlock(BlockValidationState& state, CBlockIndex* pinde
++candidate_it;
}
- // Track the last disconnected block, so we can correct its BLOCK_FAILED_CHILD status in future
- // iterations, or, if it's the last one, call InvalidChainFound on it.
+ // Track the last disconnected block to call InvalidChainFound on it.
to_mark_failed = invalid_walk_tip;
}
Why this scored 18/100
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