[PATCH] nvdimm: Fix badblocks clear off-by-one error

[PATCH] nvdimm: Fix badblocks clear off-by-one error

[Dan Williams]

From: Chris Ye <chris.ye@intel.com>

nvdimm_clear_badblocks_region() validates badblock clearing requests
against the span of the region, however it compares the inclusive
badblock request range to the exclusive region range. Fix up the
off-by-one error.

Fixes: 23f498448362 ("libnvdimm: rework region badblocks clearing")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ye <chris.ye@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/nvdimm/bus.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 7b0d1443217a..5db16857b80e 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -182,8 +182,8 @@ static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
 	ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
 
 	/* make sure we are in the region */
-	if (ctx->phys < nd_region->ndr_start
-			|| (ctx->phys + ctx->cleared) > ndr_end)
+	if (ctx->phys < nd_region->ndr_start ||
+	    (ctx->phys + ctx->cleared - 1) > ndr_end)
 		return 0;
 
 	sector = (ctx->phys - nd_region->ndr_start) / 512;

Re: [PATCH] nvdimm: Fix badblocks clear off-by-one error

[Verma, Vishal L]

On Tue, 2022-05-31 at 17:09 -0700, Dan Williams wrote:
> From: Chris Ye <chris.ye@intel.com>
> 
> nvdimm_clear_badblocks_region() validates badblock clearing requests
> against the span of the region, however it compares the inclusive
> badblock request range to the exclusive region range. Fix up the
> off-by-one error.
> 
> Fixes: 23f498448362 ("libnvdimm: rework region badblocks clearing")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Chris Ye <chris.ye@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  drivers/nvdimm/bus.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Good find! Looks good to me,

Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>

> 
> diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
> index 7b0d1443217a..5db16857b80e 100644
> --- a/drivers/nvdimm/bus.c
> +++ b/drivers/nvdimm/bus.c
> @@ -182,8 +182,8 @@ static int nvdimm_clear_badblocks_region(struct
> device *dev, void *data)
>         ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
>  
>         /* make sure we are in the region */
> -       if (ctx->phys < nd_region->ndr_start
> -                       || (ctx->phys + ctx->cleared) > ndr_end)
> +       if (ctx->phys < nd_region->ndr_start ||
> +           (ctx->phys + ctx->cleared - 1) > ndr_end)
>                 return 0;
>  
>         sector = (ctx->phys - nd_region->ndr_start) / 512;
> 
>