set_cs_start(const char* line)
{
    static int cs_start_set = 0;
    char *p, *q, *r;

    if ((p = strstr(line, "string currentfile"))
        && strstr(line, "readstring")) {
        /* locate the name of the charstring start command */
        for (q = p; q != line && q[-1] != '/'; --q)
            /* nada */;
        if (q != line) {
            for (r = q; r != p && !isspace((unsigned char) *r) && *r != '{'; ++r)
                /* nada */;
            if (cs_start_set)
                free((char*) cs_start);
            cs_start = p = malloc(r - q + 1);
            memcpy(p, q, r - q);
            p[r - q] = 0;
            cs_start_set = 1;
        }
    }
}
The software performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.