Uncache input txn in utxo cache if a tx is not accepted to mempool

random-zebra · random-zebra · commit 48baa51dd14b · 2020-08-11T01:00:58.000+02:00
>>> backports bitcoin/bitcoin@bde953e
diff --git a/src/main.cpp b/src/main.cpp
@@ -842,8 +842,9 @@ std::string FormatStateMessage(const CValidationState &state)
         state.GetRejectCode());
 }
 
-bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState& state, const CTransaction& tx, bool fLimitFree,
-        bool* pfMissingInputs, bool fOverrideMempoolLimit, bool fRejectInsaneFee, bool ignoreFees)
+bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState &state, const CTransaction &tx, bool fLimitFree,
+                              bool* pfMissingInputs, bool fOverrideMempoolLimit, bool fRejectAbsurdFee, bool ignoreFees,
+                              std::vector<uint256>& vHashTxnToUncache)
 {
     AssertLockHeld(cs_main);
     if (pfMissingInputs)
@@ -927,13 +928,19 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState& state, const CTransa
             view.SetBackend(viewMemPool);
 
             // do we already have it?
-            if (view.HaveCoins(hash))
+            bool fHadTxInCache = pcoinsTip->HaveCoinsInCache(hash);
+            if (view.HaveCoins(hash)) {
+                if (!fHadTxInCache)
+                    vHashTxnToUncache.push_back(hash);
                 return state.Invalid(false, REJECT_ALREADY_KNOWN, "txn-already-known");
+            }
 
             // do all inputs exist?
             // Note that this does not check for the presence of actual outputs (see the next check for that),
             // only helps filling in pfMissingInputs (to determine missing vs spent).
             for (const CTxIn& txin : tx.vin) {
+                if (!pcoinsTip->HaveCoinsInCache(txin.prevout.hash))
+                    vHashTxnToUncache.push_back(txin.prevout.hash);
                 if (!view.HaveCoins(txin.prevout.hash)) {
                     if (pfMissingInputs)
                         *pfMissingInputs = true;
@@ -1038,7 +1045,7 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState& state, const CTransa
             }
         }
 
-        if (fRejectInsaneFee && nFees > ::minRelayTxFee.GetFee(nSize) * 10000)
+        if (fRejectAbsurdFee && nFees > ::minRelayTxFee.GetFee(nSize) * 10000)
             return state.Invalid(false,
                 REJECT_HIGHFEE, "absurdly-high-fee",
                 strprintf("%d > %d", nFees, ::minRelayTxFee.GetFee(nSize) * 10000));
@@ -1112,6 +1119,18 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState& state, const CTransa
     return true;
 }
 
+bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransaction &tx, bool fLimitFree,
+                        bool* pfMissingInputs, bool fOverrideMempoolLimit, bool fRejectAbsurdFee, bool fIgnoreFees)
+{
+    std::vector<uint256> vHashTxToUncache;
+    bool res = AcceptToMemoryPoolWorker(pool, state, tx, fLimitFree, pfMissingInputs, fOverrideMempoolLimit, fRejectAbsurdFee, fIgnoreFees, vHashTxToUncache);
+    if (!res) {
+        for (const uint256& hashTx: vHashTxToUncache)
+            pcoinsTip->Uncache(hashTx);
+    }
+    return res;
+}
+
 bool AcceptableInputs(CTxMemPool& pool, CValidationState& state, const CTransaction& tx, bool fLimitFree, bool* pfMissingInputs, bool fRejectInsaneFee, bool isDSTX)
 {
     AssertLockHeld(cs_main);
