关于内存越界问题

内存越界两则：

1、BASE64编码，内存计算错误，导致申请的空间不够，

//ASCIItoBASE64

    len = pSUPCON_Config_File->mCDATA_Len/3;
    if(pSUPCON_Config_File->mCDATA_Len%3)
    {
        len += 1;
    }
    len = len * 4 + 1;
    pTmpContext = (char *) malloc(len);
    memset(pTmpContext,0,len);
    Base64_len = Base64_Encode(pSUPCON_Config_File->pCDATA, pSUPCON_Config_File->mCDATA_Len, pTmpContext);

原来是len/3*4，导致内存越界

2、多线程网络程序，用了两个线程不安全的函数 gmtime gethostbyname，导致内存越界，提示
Program received signal SIGSEGV, Segmentation fault.[Switching to Thread 131081 (LWP 568)]0x403f8784 in mallopt () from /lib/libc.so.6