fix(sync): fix coverity issues

source/libs/sync/src/syncMain.c

@@ -3424,7 +3424,7 @@ int32_t syncNodeDoCommit(SSyncNode* ths, SyncIndex beginIndex, SyncIndex endInde
 
         // config change finish
         if (pEntry->originalRpcType == TDMT_SYNC_CONFIG_CHANGE_FINISH) {
-          if (rpcMsg.pCont != NULL) {
+          if (rpcMsg.pCont != NULL && rpcMsg.contLen > 0) {
             code = syncNodeConfigChangeFinish(ths, &rpcMsg, pEntry);
             ASSERT(code == 0);
           }

source/libs/sync/src/syncMessage.c

@@ -3026,7 +3026,7 @@ void syncReconfigFinishFromRpcMsg(const SRpcMsg* pRpcMsg, SyncReconfigFinish* pM
 }
 
 SyncReconfigFinish* syncReconfigFinishFromRpcMsg2(const SRpcMsg* pRpcMsg) {
-  SyncReconfigFinish* pMsg = syncReconfigFinishDeserialize2(pRpcMsg->pCont, pRpcMsg->contLen);
+  SyncReconfigFinish* pMsg = syncReconfigFinishDeserialize2(pRpcMsg->pCont, (uint32_t)(pRpcMsg->contLen));
   ASSERT(pMsg != NULL);
   return pMsg;
 }