[dm-devel] [PATCH] md-raid10: fix KASAN warning

[Song Liu]

On Tue, Jul 26, 2022 at 1:33 AM Mikulas Patocka <mpatocka at redhat.com> wrote:
>
> There's a KASAN warning in raid10_remove_disk when running the lvm
> test lvconvert-raid-reshape.sh. We fix this warning by verifying that the
> value "number" is valid.
>

[...]

>  ffff889108f3d380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>  ffff889108f3d400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>
> Signed-off-by: Mikulas Patocka <mpatocka at redhat.com>
> Cc: stable at vger.kernel.org

Applied to md-next. Thanks!
Song

>
> ---
>  drivers/md/raid10.c |    5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> Index: linux-2.6/drivers/md/raid10.c
> ===================================================================
> --- linux-2.6.orig/drivers/md/raid10.c  2022-07-13 19:05:50.000000000 +0200
> +++ linux-2.6/drivers/md/raid10.c       2022-07-13 19:07:05.000000000 +0200
> @@ -2167,9 +2167,12 @@ static int raid10_remove_disk(struct mdd
>         int err = 0;
>         int number = rdev->raid_disk;
>         struct md_rdev **rdevp;
> -       struct raid10_info *p = conf->mirrors + number;
> +       struct raid10_info *p;
>
>         print_conf(conf);
> +       if (unlikely(number >= mddev->raid_disks))
> +               return 0;
> +       p = conf->mirrors + number;
>         if (rdev == p->rdev)
>                 rdevp = &p->rdev;
>         else if (rdev == p->replacement)
>