From: Hans de Goede hdegoede@redhat.com
stable inclusion from linux-4.19.171 commit 7efb1858e28b96b4ea0eac7616dc90290de42335
--------------------------------
commit 78a18fec5258c8df9435399a1ea022d73d3eceb9 upstream.
Set the acpi_device pointer which acpi_bus_get_device() returns-by- reference to NULL on errors.
We've recently had 2 cases where callers of acpi_bus_get_device() did not properly error check the return value, so set the returned- by-reference acpi_device pointer to NULL, because at least some callers of acpi_bus_get_device() expect that to be done on errors.
[ rjw: This issue was exposed by commit 71da201f38df ("ACPI: scan: Defer enumeration of devices with _DEP lists") which caused it to be much more likely to occur on some systems, but the real defect had been introduced by an earlier commit. ]
Fixes: 40e7fcb19293 ("ACPI: Add _DEP support to fix battery issue on Asus T100TA") Fixes: bcfcd409d4db ("usb: split code locating ACPI companion into port and device") Reported-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Tested-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Diagnosed-by: Rafael J. Wysocki rafael@kernel.org Signed-off-by: Hans de Goede hdegoede@redhat.com Cc: All applicable stable@vger.kernel.org [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- drivers/acpi/scan.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 46f6698c72fd..3110ac8176cb 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -586,6 +586,8 @@ static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device, if (!device) return -EINVAL;
+ *device = NULL; + status = acpi_get_data_full(handle, acpi_scan_drop_device, (void **)device, callback); if (ACPI_FAILURE(status) || !*device) {