[Libguestfs] hivex.c: unchecked calloc

[Jim Meyering]

Hi Rich,

There's an unchecked calloc in hivex.c's hive_open:

  h->bitmap = calloc (1 + h->size / 32, 1);
  ...
This subsequent deref could cause a segfault:

        BITMAP_SET (h->bitmap, blkoff);