关于使用过GetAdaptersInfo函数，内存释放的有关问题

关于使用过GetAdaptersInfo函数，内存释放的问题。
MSDN源程序：

PIP_ADAPTER_INFO   pAdapterInfo;
PIP_ADAPTER_INFO   pAdapter   =   NULL;
DWORD   dwRetVal   =   0;

pAdapterInfo   =   (IP_ADAPTER_INFO   *)   malloc(   sizeof(IP_ADAPTER_INFO)   );
ULONG   ulOutBufLen   =   sizeof(IP_ADAPTER_INFO);

//   Make   an   initial   call   to   GetAdaptersInfo   to   get
//   the   necessary   size   into   the   ulOutBufLen   variable
if   (GetAdaptersInfo(   pAdapterInfo,   &ulOutBufLen)   ==   ERROR_BUFFER_OVERFLOW)   {
    free(pAdapterInfo);
    pAdapterInfo   =   (IP_ADAPTER_INFO   *)   malloc   (ulOutBufLen);  
}

if   ((dwRetVal   =   GetAdaptersInfo(   pAdapterInfo,   &ulOutBufLen))   ==   NO_ERROR)   {
    pAdapter   =   pAdapterInfo;
    while   (pAdapter)   {
        printf( "\tAdapter   Name:   \t%s\n ",   pAdapter-> AdapterName);
        printf( "\tAdapter   Desc:   \t%s\n ",   pAdapter-> Description);
        printf( "\tAdapter   Addr:   \t%ld\n ",   pAdapter-> Address);
        printf( "\tIP   Address:   \t%s\n ",   pAdapter-> IpAddressList.IpAddress.String);
        printf( "\tIP   Mask:   \t%s\n ",   pAdapter-> IpAddressList.IpMask.String);

        printf( "\tGateway:   \t%s\n ",   pAdapter-> GatewayList.IpAddress.String);
        printf( "\t***\n ");
        if   (pAdapter-> DhcpEnabled)   {
            printf( "\tDHCP   Enabled:   Yes\n ");
            printf( "\t\tDHCP   Server:   \t%s\n ",   pAdapter-> DhcpServer.IpAddress.String);
            printf( "\tLease   Obtained:   %ld\n ",   pAdapter-> LeaseObtained);
        }
        else
            printf( "\tDHCP   Enabled:   No\n ");
       
        if   (pAdapter-> HaveWins)   {
            printf( "\tHave   Wins:   Yes\n ");
            printf( "\t\tPrimary   Wins   Server:   \t%s\n ",   pAdapter-> PrimaryWinsServer.IpAddress.String);
            printf( "\t\tSecondary   Wins   Server:   \t%s\n ",   pAdapter-> SecondaryWinsServer.IpAddress.String);
        }
        else
            printf( "\tHave   Wins:   No\n ");
        pAdapter   =   pAdapter-> Next;
    }
}
else   {
    printf( "Call   to   GetAdaptersInfo   failed.\n ");
}

pAdapter是分配空间的，为什么不需要释放呢？
我自己释放了下，一释放就出错，请高人解答。

------解决方案--------------------
释放pAdapter干什么，应该释放pAdapterInfo，再仔细看看代码吧，pAdapter又接着指向下一个节点了