Fix deadlock between blockchain and spv (#1139)

Signed-off-by: Anthony Fieroni <[email protected]> Co-authored-by: Prasanna Loganathar <[email protected]>
DeFiCh · Mar 10, 2022 · 86f554f · 86f554f
1 parent 76c94bb
commit 86f554f
Show file tree

Hide file tree

Showing 5 changed files with 10 additions and 10 deletions.
diff --git a/src/masternodes/anchors.cpp b/src/masternodes/anchors.cpp
@@ -498,7 +498,9 @@ int CAnchorIndex::GetAnchorConfirmations(const CAnchorIndex::AnchorRec * rec) co
 
 void CAnchorIndex::CheckPendingAnchors()
 {
-    AssertLockHeld(cs_main);
+    uint32_t height = spv::pspv ? spv::pspv->GetLastBlockHeight() : 0;
+
+    LOCK(cs_main);
 
     spv::PendingSet anchorsPending(spv::PendingOrder);
     ForEachPending([&anchorsPending](uint256 const &, AnchorRec & rec) {
@@ -559,24 +561,22 @@ void CAnchorIndex::CheckPendingAnchors()
 
         // Recheck anchors
         possibleReActivation = true;
-        CheckActiveAnchor();
+        CheckActiveAnchor(height);
     }
 
     for (const auto& hash : deletePending) {
         DeletePendingByBtcTx(hash);
     }
 }
 
-void CAnchorIndex::CheckActiveAnchor(bool forced)
+void CAnchorIndex::CheckActiveAnchor(uint32_t height, bool forced)
 {
     // Only continue with context of chain
     if (ShutdownRequested()) return;
 
     {
-        // fix spv height to avoid datarace while choosing best anchor
-        uint32_t const tmp = spv::pspv ? spv::pspv->GetLastBlockHeight() : 0;
         LOCK(cs_main);
-        spvLastHeight = tmp;
+        spvLastHeight = height;
 
         panchors->ActivateBestAnchor(forced);
 

diff --git a/src/masternodes/anchors.h b/src/masternodes/anchors.h
@@ -247,7 +247,7 @@ class CAnchorIndex
     int GetAnchorConfirmations(uint256 const & txHash) const;
     int GetAnchorConfirmations(AnchorRec const * rec) const;
 
-    void CheckActiveAnchor(bool forced = false);
+    void CheckActiveAnchor(uint32_t height, bool forced = false);
     void UpdateLastHeight(uint32_t height);
 
     // Post-fork anchor pending, requires chain context to validate. Some pending may be bogus, intentional or not.

diff --git a/src/spv/spv_rpc.cpp b/src/spv/spv_rpc.cpp
@@ -789,7 +789,7 @@ UniValue spv_setlastheight(const JSONRPCRequest& request)
         throw JSONRPCError(RPC_INVALID_REQUEST, "command disabled");
 
     fake_spv->lastBlockHeight = request.params[0].get_int();
-    panchors->CheckActiveAnchor(true);
+    panchors->CheckActiveAnchor(fake_spv->lastBlockHeight, true);
     return UniValue();
 }
 

diff --git a/src/spv/spv_wrapper.cpp b/src/spv/spv_wrapper.cpp
@@ -489,7 +489,8 @@ void CSpvWrapper::OnSyncStopped(int error)
 void CSpvWrapper::OnTxStatusUpdate()
 {
     LogPrint(BCLog::SPV, "tx status update\n");
-    panchors->CheckActiveAnchor();
+    uint32_t height = spv::pspv->GetLastBlockHeight();
+    panchors->CheckActiveAnchor(height);
 }
 
 void CSpvWrapper::OnSaveBlocks(int replace, BRMerkleBlock * blocks[], size_t blocksCount)

diff --git a/src/validation.cpp b/src/validation.cpp
@@ -5272,7 +5272,6 @@ bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<cons
         ProcessAuthsIfTipChanged(oldTip, tip, chainparams.GetConsensus());
 
         if (tip->nHeight >= chainparams.GetConsensus().DakotaHeight) {
-            LOCK(cs_main);
             panchors->CheckPendingAnchors();
         }
     }