Commit 215164bf authored by Mario Limonciello's avatar Mario Limonciello Committed by Hans de Goede
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platform/x86: dell-wmi-sysman: fix a NULL pointer dereference 



An upcoming Dell platform is causing a NULL pointer dereference
in dell-wmi-sysman initialization.  Validate that the input from
BIOS matches correct ACPI types and abort module initialization
if it fails.

Signed-off-by: default avatarMario Limonciello <mario.limonciello@dell.com>
Tested-by: default avatarPerry Yuan <perry_yuan@dell.com>
Link: https://lore.kernel.org/r/20210129172654.2326751-1-mario.limonciello@dell.com


[hdegoede@redhat.com: Drop redundant release_attributes_data() call]
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent 67fbe02a

drivers/platform/x86/dell-wmi-sysman/sysman.c

+5 −1
Original line number Diff line number Diff line
@@ -419,13 +419,17 @@ static int init_bios_attributes(int attr_type, const char *guid) 
		return retval;

	/* need to use specific instance_id and guid combination to get right data */

	obj = get_wmiobj_pointer(instance_id, guid);

	if (!obj)

	if (!obj || obj->type != ACPI_TYPE_PACKAGE)

		return -ENODEV;

	elements = obj->package.elements;



	mutex_lock(&wmi_priv.mutex);

	while (elements) {

		/* sanity checking */

		if (elements[ATTR_NAME].type != ACPI_TYPE_STRING) {

			pr_debug("incorrect element type\n");

			goto nextobj;

		}

		if (strlen(elements[ATTR_NAME].string.pointer) == 0) {

			pr_debug("empty attribute found\n");

			goto nextobj;