Re: [PATCH] acpi, nfit: fix register dimm error handling

[Kani, Toshi]

On Fri, 2018-02-02 at 12:31 -0800, Dan Williams wrote:
> On Fri, Feb 2, 2018 at 1:00 PM, Toshi Kani <toshi.kani@xxxxxxx> wrote:
> > A NULL pointer reference kernel bug was observed when
> > acpi_nfit_add_dimm() called in acpi_nfit_register_dimms()
> > failed. This error path does not set nfit_mem->nvdimm, but
> > the 2nd list_for_each_entry() loop in the function assumes
> > it's always set. Add a check to nfit_mem->nvdimm.
> > 
> > Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx>
> > Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> > Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> > ---
> >  drivers/acpi/nfit/core.c |    3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> > index abeb4df4f22e..b28ce440a06f 100644
> > --- a/drivers/acpi/nfit/core.c
> > +++ b/drivers/acpi/nfit/core.c
> > @@ -1867,6 +1867,9 @@ static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
> >                 struct kernfs_node *nfit_kernfs;
> > 
> >                 nvdimm = nfit_mem->nvdimm;
> > +               if (!nvdimm)
> > +                       continue;
> > +
> >                 nfit_kernfs = sysfs_get_dirent(nvdimm_kobj(nvdimm)->sd, "nfit");
> >                 if (nfit_kernfs)
> >                         nfit_mem->flags_attr = sysfs_get_dirent(nfit_kernfs,
> 
> Yes, I assume this also needs:
> 
> Cc: <stable@xxxxxxxxxxxxxxx>
> Fixes: ba9c8dd3c222 ("acpi, nfit: add dimm device notification support")

Right. Thanks!
-Toshi