Re: [PATCH] md/raid10: fix divide-by-zero in setup_geo() with zero far_copies

[Yuhao Jiang]

Hi Kuai,

So in this case, how should my name be shown on this security patch?
Because I reported this bug. Most maintainers added my name in the
reported-by tag.

Thanks,
Yuhao

On Wed, May 20, 2026 at 6:52 AM Yu Kuai <yukuai@xxxxxxxxx> wrote:
>
> Hi,
>
> 在 2026/4/28 16:37, Yuhao Jiang 写道:
> > Hi Kuai,
> >
> > Looks like different maintainers have different rules. :(
> > Can you send me the patchwork resource?
>
> Usually just a link to lore url is enough.
>
> >
> > Thanks.
> >
> > On Tue, Apr 28, 2026 at 4:32 PM Yu Kuai <yukuai@xxxxxxxxx> wrote:
> >> Hi,
> >>
> >> 在 2026/4/19 13:59, Yuhao Jiang 写道:
> >>> Hi Kuai,
> >>>
> >>> This report was reported by me, so Junrui added me as Reported-by.
> >> This is fine, however, please do not add downstream reported-by tag.
> >> If you want to add the reported-by tag, please report the problem to
> >> patchwork first. :)
> >>
> >>> Thanks,
> >>>
> >>> On Sun, Apr 19, 2026 at 12:43 AM Yu Kuai <yukuai@xxxxxxxxx> wrote:
> >>>
> >>>      Hi,
> >>>
> >>>      在 2026/4/16 11:39, Junrui Luo 写道:
> >>>      > setup_geo() extracts near_copies (nc) and far_copies (fc) from the
> >>>      > user-provided layout parameter without checking for zero. When fc=0
> >>>      > with the "improved" far set layout selected, 'geo->far_set_size =
> >>>      > disks / fc' triggers a divide-by-zero.
> >>>      >
> >>>      > Validate nc and fc immediately after extraction, returning -1 if
> >>>      > either is zero.
> >>>      >
> >>>      > Fixes: 475901aff158 ("MD RAID10: Improve redundancy for 'far'
> >>>      and 'offset' algorithms (part 1)")
> >>>      > Reported-by: Yuhao Jiang<danisjiang@xxxxxxxxx>
> >>>
> >>>      So again I can't find a report, and Reported-by usually should be
> >>>      followed
> >>>      by a Closes link to the original report.
> >>>
> >>>      Applied with Reported-by tag removed.
> >>>
> >>>      > Cc:stable@xxxxxxxxxxxxxxx <mailto:Cc%3Astable@xxxxxxxxxxxxxxx>
> >>>      > Signed-off-by: Junrui Luo<moonafterrain@xxxxxxxxxxx>
> >>>      > ---
> >>>      >   drivers/md/raid10.c | 2 ++
> >>>      >   1 file changed, 2 insertions(+)
> >>>
> >>>      --
> >>>      Thansk,
> >>>      Kuai
> >>>
> >>>
> >>>
> >>> --
> >>> Yuhao Jiang
> >> --
> >> Thansk,
> >> Kuai
> >
> >
> --
> Thansk,
> Kuai



-- 
Yuhao Jiang