mirror of
https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git
synced 2026-10-29 03:01:39 -04:00
efi: Restrict efivar_ssdt_load when the kernel is locked down
efivar_ssdt_load allows the kernel to import arbitrary ACPI code from an EFI variable, which gives arbitrary code execution in ring 0. Prevent that when the kernel is locked down. Signed-off-by: Matthew Garrett <[email protected]> Acked-by: Ard Biesheuvel <[email protected]> Reviewed-by: Kees Cook <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: [email protected] Signed-off-by: James Morris <[email protected]>
This commit is contained in:
parent
ccbd54ff54
commit
1957a85b00
1 changed files with 6 additions and 0 deletions
|
|
@ -30,6 +30,7 @@
|
|||
#include <linux/acpi.h>
|
||||
#include <linux/ucs2_string.h>
|
||||
#include <linux/memblock.h>
|
||||
#include <linux/security.h>
|
||||
|
||||
#include <asm/early_ioremap.h>
|
||||
|
||||
|
|
@ -241,6 +242,11 @@ static void generic_ops_unregister(void)
|
|||
static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
|
||||
static int __init efivar_ssdt_setup(char *str)
|
||||
{
|
||||
int ret = security_locked_down(LOCKDOWN_ACPI_TABLES);
|
||||
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (strlen(str) < sizeof(efivar_ssdt))
|
||||
memcpy(efivar_ssdt, str, strlen(str));
|
||||
else
|
||||
|
|
|
|||
Loading…
Reference in a new issue