[net processing] ignore unknown INV types in GETDATA messages

Co-Authored-By: John Newbery <john@johnnewbery.com>

src/net_processing.cpp

@@ -1645,18 +1645,14 @@ void static ProcessGetData(CNode* pfrom, const CChainParams& chainparams, CConnm
     } // release cs_main
 
     if (it != pfrom->vRecvGetData.end() && !pfrom->fPauseSend) {
-        const CInv &inv = *it;
+        const CInv &inv = *it++;
         if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK || inv.type == MSG_CMPCT_BLOCK || inv.type == MSG_WITNESS_BLOCK) {
-            it++;
             ProcessGetBlockData(pfrom, chainparams, inv, connman);
         }
+        // else: If the first item on the queue is an unknown type, we erase it
+        // and continue processing the queue on the next call.
     }
 
-    // Unknown types in the GetData stay in vRecvGetData and block any future
-    // message from this peer, see vRecvGetData check in ProcessMessages().
-    // Depending on future p2p changes, we might either drop unknown getdata on
-    // the floor or disconnect the peer.
-
     pfrom->vRecvGetData.erase(pfrom->vRecvGetData.begin(), it);
 
     if (!vNotFound.empty()) {