Re: [PATCH v4 6/6] ntfs: validate resident index root values on lookup

[Namjae Jeon]

> +static bool ntfs_index_root_attr_value_is_valid(const u8 *value, const u32 value_length)
> +{
> +       const struct index_root *ir;
> +       u32 index_size;
> +       u32 entries_offset;
> +       u32 index_length;
> +       u32 allocated_size;
> +
> +       ir = (const struct index_root *)value;
> +       index_size = value_length - offsetof(struct index_root, index);
> +       entries_offset = le32_to_cpu(ir->index.entries_offset);
> +       index_length = le32_to_cpu(ir->index.index_length);
> +       allocated_size = le32_to_cpu(ir->index.allocated_size);
> +
> +       if ((entries_offset | index_length | allocated_size) & 7 ||
> +           entries_offset < sizeof(struct index_header) ||
> +           entries_offset > index_length ||
> +           index_length > allocated_size ||
> +           allocated_size > index_size ||
If ntfs driver does not use the allocated_size field of index root,
how about removing the allocated_size checks ?
we can also skip the shrink/grow ordering adjustment in
ntfs_ir_truncate() in your 0005 patch.

> +           index_length - entries_offset < sizeof(struct index_entry_header))
> +               return false;
> +
> +       return true;
> +}
> +