message: fix invalid free.
diff: @@ -752,7 +752,7 @@ static PHP_METHOD(swoole_coroutine_util, fread)
  }
  off_t _seek = lseek(fd, 0, SEEK_CUR);
  - if (length <= 0)
  + if (length <= 0 || file_stat.st_size - _seek < length)
  {
  length = file_stat.st_size - _seek;
  }
  @@ -760,8 +760,8 @@ static PHP_METHOD(swoole_coroutine_util, fread)
  swAio_event ev;
  bzero(&ev, sizeof(swAio_event));
  - ev.nbytes = length;
  - ev.buf = sw_malloc(ev.nbytes);
  + ev.nbytes = length + 1;
  + ev.buf = emalloc(ev.nbytes);
  if (!ev.buf)
  {
  RETURN_FALSE;
  