Commit 4bb1e7d0 authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Rafael J. Wysocki
Browse files

ACPI: sysfs: validate return type of _STR method 



Only buffer objects are valid return values of _STR.

If something else is returned description_show() will access invalid
memory.

Fixes: d1efe3c3 ("ACPI: Add new sysfs interface to export device description")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Link: https://patch.msgid.link/20240709-acpi-sysfs-groups-v2-1-058ab0667fa8@weissschuh.net


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 8400291e

drivers/acpi/device_sysfs.c

+3 −2
Original line number Diff line number Diff line
@@ -540,8 +540,9 @@ int acpi_device_setup_files(struct acpi_device *dev) 
	 * If device has _STR, 'description' file is created

	 */

	if (acpi_has_method(dev->handle, "_STR")) {

		status = acpi_evaluate_object(dev->handle, "_STR",

					NULL, &buffer);

		status = acpi_evaluate_object_typed(dev->handle, "_STR",

						    NULL, &buffer,

						    ACPI_TYPE_BUFFER);

		if (ACPI_FAILURE(status))

			buffer.pointer = NULL;

		dev->pnp.str_obj = buffer.pointer;