On Fri, Feb 2, 2018 at 1:00 PM, Toshi Kani <toshi.kani(a)hpe.com&gt; 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(a)hpe.com&gt; > Cc: Dan Williams <dan.j.williams(a)intel.com&gt; > Cc: "Rafael J. Wysocki" <rjw(a)rjwysocki.net&gt; > --- > 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(a)vger.kernel.org&gt; Fixes: ba9c8dd3c222 ("acpi, nfit: add dimm device notification support")