Move [clean|str]SubVer writes/copyStats into a lock

Author: TheBlueMatt

src/net.cpp

@@ -610,7 +610,10 @@ void CNode::copyStats(CNodeStats &stats)
     X(nTimeOffset);
     X(addrName);
     X(nVersion);
-    X(cleanSubVer);
+    {
+        LOCK(cs_SubVer);
+        X(cleanSubVer);
+    }
     X(fInbound);
     X(fAddnode);
     X(nStartingHeight);

src/net.h

@@ -598,6 +598,7 @@ class CNode
     // store the sanitized version in cleanSubVer. The original should be used when dealing with
     // the network or wire types and the cleaned string used when displayed or logged.
     std::string strSubVer, cleanSubVer;
+    CCriticalSection cs_SubVer; // used for both cleanSubVer and strSubVer
     bool fWhitelisted; // This peer can bypass DoS banning.
     bool fFeeler; // If true this node is being used as a short lived feeler.
     bool fOneShot;

src/net_processing.cpp

@@ -1211,6 +1211,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         int nVersion;
         int nSendVersion;
         std::string strSubVer;
+        std::string cleanSubVer;
         int nStartingHeight = -1;
         bool fRelay = true;
 
@@ -1246,6 +1247,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             vRecv >> addrFrom >> nNonce;
         if (!vRecv.empty()) {
             vRecv >> LIMITED_STRING(strSubVer, MAX_SUBVERSION_LENGTH);
+            cleanSubVer = SanitizeString(strSubVer);
         }
         if (!vRecv.empty()) {
             vRecv >> nStartingHeight;
@@ -1273,8 +1275,11 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
 
         pfrom->nServices = nServices;
         pfrom->addrLocal = addrMe;
-        pfrom->strSubVer = strSubVer;
-        pfrom->cleanSubVer = SanitizeString(strSubVer);
+        {
+            LOCK(pfrom->cs_SubVer);
+            pfrom->strSubVer = strSubVer;
+            pfrom->cleanSubVer = cleanSubVer;
+        }
         pfrom->nStartingHeight = nStartingHeight;
         pfrom->fClient = !(nServices & NODE_NETWORK);
         {
@@ -1330,7 +1335,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             remoteAddr = ", peeraddr=" + pfrom->addr.ToString();
 
         LogPrintf("receive version message: %s: version %d, blocks=%d, us=%s, peer=%d%s\n",
-                  pfrom->cleanSubVer, pfrom->nVersion,
+                  cleanSubVer, pfrom->nVersion,
                   pfrom->nStartingHeight, addrMe.ToString(), pfrom->id,
                   remoteAddr);