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

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,