ACPI: Limit access to custom_method when the kernel is locked down

custom_method effectively allows arbitrary access to system memory, making
it possible for an attacker to circumvent restrictions on module loading.
Disable it if the kernel is locked down.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-acpi@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Matthew Garrett
2019-08-19 17:17:50 -07:00
committed by James Morris
parent 95f5e95f41
commit f474e1486b
3 changed files with 8 additions and 0 deletions

View File

@@ -25,6 +25,7 @@ static char *lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
[LOCKDOWN_PCI_ACCESS] = "direct PCI access",
[LOCKDOWN_IOPORT] = "raw io port access",
[LOCKDOWN_MSR] = "raw MSR access",
[LOCKDOWN_ACPI_TABLES] = "modifying ACPI tables",
[LOCKDOWN_INTEGRITY_MAX] = "integrity",
[LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
};