[#9102] really don't validate genesis block

Author: instagibbs

src/validation.cpp

@@ -1091,8 +1091,10 @@ bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus:
     }
 
     // Check the header
-    if (!CheckProofOfWork(block.GetHash(), block.nBits, consensusParams))
+    if (block.GetHash() != consensusParams.hashGenesisBlock &&
+            !CheckProofOfWork(block.GetHash(), block.nBits, consensusParams)) {
         return error("ReadBlockFromDisk: Errors in block header at %s", pos.ToString());
+    }
 
     return true;
 }
@@ -1810,6 +1812,22 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
     assert(*pindex->phashBlock == block.GetHash());
     int64_t nTimeStart = GetTimeMicros();
 
+    // verify that the view's current state corresponds to the previous block
+    uint256 hashPrevBlock = pindex->pprev == nullptr ? uint256() : pindex->pprev->GetBlockHash();
+    assert(hashPrevBlock == view.GetBestBlock());
+
+    // Add genesis outputs but don't validate.
+    if (block.GetHash() == chainparams.GetConsensus().hashGenesisBlock) {
+        if (!fJustCheck) {
+            for (const auto& tx : block.vtx) {
+                // Directly add new coins to DB
+                AddCoins(view, *tx, 0);
+            }
+            view.SetBestBlock(pindex->GetBlockHash());
+        }
+        return true;
+    }
+
     // Check it again in case a previous version let a bad block in
     // NOTE: We don't currently (re-)invoke ContextualCheckBlock() or
     // ContextualCheckBlockHeader() here. This means that if we add a new
@@ -1833,22 +1851,6 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
         return error("%s: Consensus::CheckBlock: %s", __func__, FormatStateMessage(state));
     }
 
-    // verify that the view's current state corresponds to the previous block
-    uint256 hashPrevBlock = pindex->pprev == nullptr ? uint256() : pindex->pprev->GetBlockHash();
-    assert(hashPrevBlock == view.GetBestBlock());
-
-    // Add genesis outputs but don't validate.
-    if (block.GetHash() == chainparams.GetConsensus().hashGenesisBlock) {
-        if (!fJustCheck) {
-            for (const auto& tx : block.vtx) {
-                // Directly add new coins to DB
-                AddCoins(view, *tx, 0);
-            }
-            view.SetBestBlock(pindex->GetBlockHash());
-        }
-        return true;
-    }
-
     nBlocksTotal++;
 
     bool fScriptChecks = true;
@@ -3083,9 +3085,10 @@ static bool FindUndoPos(CValidationState &state, int nFile, CDiskBlockPos &pos,
 static bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true)
 {
     // Check proof of work matches claimed amount
-    if (fCheckPOW && !CheckProofOfWork(block.GetHash(), block.nBits, consensusParams))
+    if (fCheckPOW && block.GetHash() != consensusParams.hashGenesisBlock
+            && !CheckProofOfWork(block.GetHash(), block.nBits, consensusParams)) {
         return state.DoS(50, false, REJECT_INVALID, "high-hash", false, "proof of work failed");
-
+    }
     return true;
 }
 
@@ -3502,8 +3505,9 @@ bool CChainState::AcceptBlock(const std::shared_ptr<const CBlock>& pblock, CVali
         if (pindex->nChainWork < nMinimumChainWork) return true;
     }
 
-    if (!CheckBlock(block, state, chainparams.GetConsensus()) ||
-        !ContextualCheckBlock(block, state, chainparams.GetConsensus(), pindex->pprev)) {
+    if (block.GetHash() != chainparams.GetConsensus().hashGenesisBlock &&
+            (!CheckBlock(block, state, chainparams.GetConsensus()) ||
+        !ContextualCheckBlock(block, state, chainparams.GetConsensus(), pindex->pprev))) {
         if (state.IsInvalid() && !state.CorruptionPossible()) {
             pindex->nStatus |= BLOCK_FAILED_VALID;
             setDirtyBlockIndex.insert(pindex);