ACPICA: debugger: check status of acpi_evaluate_object() in acpi_db_w…

…alk_for_fields()

[ Upstream commit 40e2710 ]

ACPICA commit 9061cd9aa131205657c811a52a9f8325a040c6c9

Errors in acpi_evaluate_object() can lead to incorrect state of buffer.

This can lead to access to data in previously ACPI_FREEd buffer and
secondary ACPI_FREE to the same buffer later.

Handle errors in acpi_evaluate_object the same way it is done earlier
with acpi_ns_handle_to_pathname.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Link: acpica/acpica@9061cd9a
Fixes: 5fd0332 ("ACPICA: debugger: add command to dump all fields of particular subtype")
Signed-off-by: Nikita Kiryushin <kiryushin@ancud.ru>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/acpi/acpica/dbnames.c

@@ -550,8 +550,12 @@ acpi_db_walk_for_fields(acpi_handle obj_handle,
 	ACPI_FREE(buffer.pointer);
 
 	buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
-	acpi_evaluate_object(obj_handle, NULL, NULL, &buffer);
-
+	status = acpi_evaluate_object(obj_handle, NULL, NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		acpi_os_printf("Could Not evaluate object %p\n",
+			       obj_handle);
+		return (AE_OK);
+	}
 	/*
 	 * Since this is a field unit, surround the output in braces
 	 */