* Re: [PATCH] dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range()
2026-04-12 15:50 ` [PATCH] dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range() John Groves
@ 2026-04-13 15:19 ` Jonathan Cameron
2026-04-13 16:12 ` Dave Jiang
1 sibling, 0 replies; 3+ messages in thread
From: Jonathan Cameron @ 2026-04-13 15:19 UTC (permalink / raw)
To: John Groves
Cc: Dan Williams, Vishal Verma, Dave Jiang, Ira Weiny, nvdimm,
linux-cxl, linux-kernel, Dan Carpenter, John Groves
On Sun, 12 Apr 2026 15:50:06 +0000
John Groves <john@jagalactic.com> wrote:
> From: John Groves <John@Groves.net>
>
> __fsdev_dax_direct_access() returns -EFAULT without setting *kaddr when
> dax_pgoff_to_phys() returns -1 (pgoff out of range). The return value
> was ignored, leaving kaddr uninitialized before being passed to
> fsdev_write_dax().
>
> Check the return value and propagate the error.
>
> Thanks to Dan Carpenter and the smatch project for reporting this.
>
> Signed-off-by: John Groves <john@groves.net>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range()
2026-04-12 15:50 ` [PATCH] dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range() John Groves
2026-04-13 15:19 ` Jonathan Cameron
@ 2026-04-13 16:12 ` Dave Jiang
1 sibling, 0 replies; 3+ messages in thread
From: Dave Jiang @ 2026-04-13 16:12 UTC (permalink / raw)
To: John Groves, Dan Williams, Vishal Verma, Ira Weiny, nvdimm, linux-cxl
Cc: linux-kernel, Dan Carpenter, John Groves
On 4/12/26 8:50 AM, John Groves wrote:
> From: John Groves <John@Groves.net>
>
> __fsdev_dax_direct_access() returns -EFAULT without setting *kaddr when
> dax_pgoff_to_phys() returns -1 (pgoff out of range). The return value
> was ignored, leaving kaddr uninitialized before being passed to
> fsdev_write_dax().
>
> Check the return value and propagate the error.
>
> Thanks to Dan Carpenter and the smatch project for reporting this.
>
> Signed-off-by: John Groves <john@groves.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
> drivers/dax/fsdev.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dax/fsdev.c b/drivers/dax/fsdev.c
> index 4499d9621f33..188b2526bee4 100644
> --- a/drivers/dax/fsdev.c
> +++ b/drivers/dax/fsdev.c
> @@ -80,9 +80,12 @@ static int fsdev_dax_zero_page_range(struct dax_device *dax_dev,
> pgoff_t pgoff, size_t nr_pages)
> {
> void *kaddr;
> + long rc;
>
> WARN_ONCE(nr_pages > 1, "%s: nr_pages > 1\n", __func__);
> - __fsdev_dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);
> + rc = __fsdev_dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);
> + if (rc < 0)
> + return rc;
> fsdev_write_dax(kaddr, ZERO_PAGE(0), 0, PAGE_SIZE);
> return 0;
> }
>
> base-commit: 2ae624d5a555d47a735fb3f4d850402859a4db77
^ permalink raw reply [flat|nested] 3+ messages in thread