On Fri, Jun 21, 2019 at 05:03:44PM -0700, Matthew Garrett wrote: > From: Josh Boyer <jwboyer@xxxxxxxxxx> > > This option allows userspace to pass the RSDP address to the kernel, which > makes it possible for a user to modify the workings of hardware . Reject > the option when the kernel is locked down. > > Signed-off-by: Josh Boyer <jwboyer@xxxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -Kees > Signed-off-by: David Howells <dhowells@xxxxxxxxxx> > Signed-off-by: Matthew Garrett <mjg59@xxxxxxxxxx> > cc: Dave Young <dyoung@xxxxxxxxxx> > cc: linux-acpi@xxxxxxxxxxxxxxx > --- > drivers/acpi/osl.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c > index f29e427d0d1d..60cda8a0f36b 100644 > --- a/drivers/acpi/osl.c > +++ b/drivers/acpi/osl.c > @@ -40,6 +40,7 @@ > #include <linux/list.h> > #include <linux/jiffies.h> > #include <linux/semaphore.h> > +#include <linux/security.h> > > #include <asm/io.h> > #include <linux/uaccess.h> > @@ -194,7 +195,7 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) > acpi_physical_address pa; > > #ifdef CONFIG_KEXEC > - if (acpi_rsdp) > + if (acpi_rsdp && !security_locked_down(LOCKDOWN_ACPI_TABLES)) > return acpi_rsdp; > #endif > pa = acpi_arch_get_root_pointer(); > -- > 2.22.0.410.gd8fdbe21b5-goog > -- Kees Cook
