Re: [PATCH 2/8] bitmap: Introduce bitmap_set, bitmap_clear,

FUJITA Tomonori
2009-10-17T13:43:02Z

On Tue, 13 Oct 2009 18:10:17 +0900
Akinobu Mita <akinobu.mita@gmail.com> wrote:

> My user space testing exposed off-by-one error find_next_zero_area
> in iommu-helper. Some zero area cannot be found by this bug.
>
> Subject: [PATCH] Fix off-by-one error in find_next_zero_area
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> ---
> lib/iommu-helper.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c
> index 75dbda0..afc58bc 100644
> --- a/lib/iommu-helper.c
> +++ b/lib/iommu-helper.c
> @@ -19,7 +19,7 @@ again:
> index = (index + align_mask) & ~align_mask;
>
> end = index + nr;
> - if (end >= size)
> + if (end > size)

I think that this is intentional; the last byte of the limit doesn't
work.