Merge #18458: net: Add missing cs_vNodes lock

fa369651c5523f393e0bfcfa328b8e27006711aa net: Add missing cs_vNodes lock (MarcoFalke)

Pull request description:

  Fixes #18457

ACKs for top commit:
  promag:
    Code review ACK fa369651c5523f393e0bfcfa328b8e27006711aa.
  laanwj:
    ACK fa369651c5523f393e0bfcfa328b8e27006711aa

Tree-SHA512: 60d7000f2f3d480bb0953ce27a0020763e7102da16a0006b619e0a236cfc33cbd4f83d870e9f0546639711cd877c1f9808d419184bbc153bb328885417e0066c

src/init.cpp

@@ -197,7 +197,20 @@ void Shutdown(NodeContext& node)
     // Because these depend on each-other, we make sure that neither can be
     // using the other before destroying them.
     if (node.peer_logic) UnregisterValidationInterface(node.peer_logic.get());
-    if (node.connman) node.connman->Stop();
+    // Follow the lock order requirements:
+    // * CheckForStaleTipAndEvictPeers locks cs_main before indirectly calling GetExtraOutboundCount
+    //   which locks cs_vNodes.
+    // * ProcessMessage locks cs_main and g_cs_orphans before indirectly calling ForEachNode which
+    //   locks cs_vNodes.
+    // * CConnman::Stop calls DeleteNode, which calls FinalizeNode, which locks cs_main and calls
+    //   EraseOrphansFor, which locks g_cs_orphans.
+    //
+    // Thus the implicit locking order requirement is: (1) cs_main, (2) g_cs_orphans, (3) cs_vNodes.
+    if (node.connman) {
+        node.connman->StopThreads();
+        LOCK2(::cs_main, ::g_cs_orphans);
+        node.connman->StopNodes();
+    }
 
     StopTorControl();
 

src/net.cpp

@@ -2387,7 +2387,7 @@ void CConnman::Interrupt()
     }
 }
 
-void CConnman::Stop()
+void CConnman::StopThreads()
 {
     if (threadMessageHandler.joinable())
         threadMessageHandler.join();
@@ -2399,14 +2399,17 @@ void CConnman::Stop()
         threadDNSAddressSeed.join();
     if (threadSocketHandler.joinable())
         threadSocketHandler.join();
+}
 
-    if (fAddressesInitialized)
-    {
+void CConnman::StopNodes()
+{
+    if (fAddressesInitialized) {
         DumpAddresses();
         fAddressesInitialized = false;
     }
 
     // Close sockets
+    LOCK(cs_vNodes);
     for (CNode* pnode : vNodes)
         pnode->CloseSocketDisconnect();
     for (ListenSocket& hListenSocket : vhListenSocket)
@@ -2415,10 +2418,10 @@ void CConnman::Stop()
                 LogPrintf("CloseSocket(hListenSocket) failed with error %s\n", NetworkErrorString(WSAGetLastError()));
 
     // clean up some globals (to help leak detection)
-    for (CNode *pnode : vNodes) {
+    for (CNode* pnode : vNodes) {
         DeleteNode(pnode);
     }
-    for (CNode *pnode : vNodesDisconnected) {
+    for (CNode* pnode : vNodesDisconnected) {
         DeleteNode(pnode);
     }
     vNodes.clear();
@@ -2433,7 +2436,7 @@ void CConnman::DeleteNode(CNode* pnode)
     assert(pnode);
     bool fUpdateConnectionTime = false;
     m_msgproc->FinalizeNode(pnode->GetId(), fUpdateConnectionTime);
-    if(fUpdateConnectionTime) {
+    if (fUpdateConnectionTime) {
         addrman.Connected(pnode->addr);
     }
     delete pnode;

src/net.h

@@ -188,16 +188,13 @@ public:
     ~CConnman();
     bool Start(CScheduler& scheduler, const Options& options);
 
-    // TODO: Remove NO_THREAD_SAFETY_ANALYSIS. Lock cs_vNodes before reading the variable vNodes.
-    //
-    // When removing NO_THREAD_SAFETY_ANALYSIS be aware of the following lock order requirements:
-    // * CheckForStaleTipAndEvictPeers locks cs_main before indirectly calling GetExtraOutboundCount
-    //   which locks cs_vNodes.
-    // * ProcessMessage locks cs_main and g_cs_orphans before indirectly calling ForEachNode which
-    //   locks cs_vNodes.
-    //
-    // Thus the implicit locking order requirement is: (1) cs_main, (2) g_cs_orphans, (3) cs_vNodes.
-    void Stop() NO_THREAD_SAFETY_ANALYSIS;
+    void StopThreads();
+    void StopNodes();
+    void Stop()
+    {
+        StopThreads();
+        StopNodes();
+    };
 
     void Interrupt();
     bool GetNetworkActive() const { return fNetworkActive; };

src/net_processing.h

@@ -14,6 +14,7 @@
 class CTxMemPool;
 
 extern RecursiveMutex cs_main;
+extern RecursiveMutex g_cs_orphans;
 
 /** Default for -maxorphantx, maximum number of orphan transactions kept in memory */
 static const unsigned int DEFAULT_MAX_ORPHAN_TRANSACTIONS = 100;

src/test/denialofservice_tests.cpp

@@ -52,7 +52,6 @@ struct COrphanTx {
     NodeId fromPeer;
     int64_t nTimeExpire;
 };
-extern RecursiveMutex g_cs_orphans;
 extern std::map<uint256, COrphanTx> mapOrphanTransactions GUARDED_BY(g_cs_orphans);
 
 static CService ip(uint32_t i)