From efb54ba065e41e0d36383bcabfcc01bbca7b2340 Mon Sep 17 00:00:00 2001 From: Kaz Wesley Date: Mon, 25 Apr 2016 13:13:52 -0700 Subject: [PATCH 1/2] lock cs_main for State/Misbehaving ProcessMessage calls State(...) and Misbehaving(...) without holding the required lock; add LOCK(cs_main) blocks. --- src/main.cpp | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/src/main.cpp b/src/main.cpp index f6a89fa2e..a85ee46d5 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -4514,6 +4514,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, strCommand == NetMsgType::FILTERCLEAR)) { if (pfrom->nVersion >= NO_BLOOM_VERSION) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 100); return false; } else { @@ -4529,6 +4530,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, if (pfrom->nVersion != 0) { pfrom->PushMessage(NetMsgType::REJECT, strCommand, REJECT_DUPLICATE, string("Duplicate version message")); + LOCK(cs_main); Misbehaving(pfrom->GetId(), 1); return false; } @@ -4584,7 +4586,10 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, pfrom->fClient = !(pfrom->nServices & NODE_NETWORK); // Potentially mark this peer as a preferred download peer. + { + LOCK(cs_main); UpdatePreferredDownload(pfrom, State(pfrom->GetId())); + } // Change version pfrom->PushMessage(NetMsgType::VERACK); @@ -4642,6 +4647,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, else if (pfrom->nVersion == 0) { // Must have a version message before anything else + LOCK(cs_main); Misbehaving(pfrom->GetId(), 1); return false; } @@ -4677,6 +4683,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, return true; if (vAddr.size() > 1000) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 20); return error("message addr size() = %u", vAddr.size()); } @@ -4746,6 +4753,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, vRecv >> vInv; if (vInv.size() > MAX_INV_SZ) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 20); return error("message inv size() = %u", vInv.size()); } @@ -4821,6 +4829,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, vRecv >> vInv; if (vInv.size() > MAX_INV_SZ) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 20); return error("message getdata size() = %u", vInv.size()); } @@ -5074,6 +5083,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, // Bypass the normal CBlock deserialization, as we don't want to risk deserializing 2000 full blocks. unsigned int nCount = ReadCompactSize(vRecv); if (nCount > MAX_HEADERS_RESULTS) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 20); return error("headers message size = %u", nCount); } @@ -5350,8 +5360,11 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, vRecv >> filter; if (!filter.IsWithinSizeConstraints()) + { // There is no excuse for sending a too-large filter + LOCK(cs_main); Misbehaving(pfrom->GetId(), 100); + } else { LOCK(pfrom->cs_filter); @@ -5372,13 +5385,17 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, // and thus, the maximum size any matched object can have) in a filteradd message if (vData.size() > MAX_SCRIPT_ELEMENT_SIZE) { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 100); } else { LOCK(pfrom->cs_filter); if (pfrom->pfilter) pfrom->pfilter->insert(vData); else + { + LOCK(cs_main); Misbehaving(pfrom->GetId(), 100); + } } } From 719de56ab2c8e5bc6ce9f67c7bf159adc242d49b Mon Sep 17 00:00:00 2001 From: Kaz Wesley Date: Mon, 25 Apr 2016 12:31:32 -0700 Subject: [PATCH 2/2] lock cs_main for chainActive ActivateBestChain uses chainActive after releasing the lock; reorder operations to move all access to synchronized object into existing LOCK(cs_main) block. --- src/main.cpp | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/src/main.cpp b/src/main.cpp index a85ee46d5..83fc4d6bd 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -2897,14 +2897,15 @@ static bool ActivateBestChainStep(CValidationState& state, const CChainParams& c */ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, const CBlock *pblock) { CBlockIndex *pindexMostWork = NULL; + CBlockIndex *pindexNewTip = NULL; do { boost::this_thread::interruption_point(); if (ShutdownRequested()) break; - CBlockIndex *pindexNewTip = NULL; const CBlockIndex *pindexFork; bool fInitialDownload; + int nNewHeight; { LOCK(cs_main); CBlockIndex *pindexOldTip = chainActive.Tip(); @@ -2920,6 +2921,7 @@ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, pindexNewTip = chainActive.Tip(); pindexFork = chainActive.FindFork(pindexOldTip); fInitialDownload = IsInitialBlockDownload(); + nNewHeight = chainActive.Height(); } // When we reach this point, we switched to a new tip (stored in pindexNewTip). @@ -2948,7 +2950,7 @@ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, { LOCK(cs_vNodes); BOOST_FOREACH(CNode* pnode, vNodes) { - if (chainActive.Height() > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate)) { + if (nNewHeight > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate)) { BOOST_REVERSE_FOREACH(const uint256& hash, vHashes) { pnode->PushBlockHash(hash); } @@ -2961,7 +2963,7 @@ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, } } } - } while(pindexMostWork != chainActive.Tip()); + } while (pindexNewTip != pindexMostWork); CheckBlockIndex(chainparams.GetConsensus()); // Write changes periodically to disk, after relay.