Commit-ID: 30d7bf034c034995f34dae265d96247f7f12044e
Gitweb: http://git.kernel.org/tip/30d7bf034c034995f34dae265d96247f7f12044e
Author: Linn Crosetto <[email protected]>
AuthorDate: Mon, 25 Apr 2016 21:06:37 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 28 Apr 2016 11:33:49 +0200
efi/arm64: Check SetupMode when determining Secure Boot status
According to the UEFI specification (version 2.5 Errata A, page 87):
The platform firmware is operating in secure boot mode if the value of
the SetupMode variable is 0 and the SecureBoot variable is set to 1. A
platform cannot operate in secure boot mode if the SetupMode variable
is set to 1.
Check the value of the SetupMode variable when determining the state of
Secure Boot.
Plus also do minor cleanup, change sizeof() use to match kernel style
guidelines.
Signed-off-by: Linn Crosetto <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Reviewed-by: Ard Biesheuvel <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Roy Franz <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link:
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/libstub/arm-stub.c | 32 +++++++++++++++++++++++++-------
1 file changed, 25 insertions(+), 7 deletions(-)
diff --git a/drivers/firmware/efi/libstub/arm-stub.c
b/drivers/firmware/efi/libstub/arm-stub.c
index 07f967c..1286325 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -22,21 +22,39 @@ bool __nokaslr;
static int efi_get_secureboot(efi_system_table_t *sys_table_arg)
{
- static efi_guid_t const var_guid = EFI_GLOBAL_VARIABLE_GUID;
- static efi_char16_t const var_name[] = {
+ static efi_char16_t const sb_var_name[] = {
'S', 'e', 'c', 'u', 'r', 'e', 'B', 'o', 'o', 't', 0 };
+ static efi_char16_t const sm_var_name[] = {
+ 'S', 'e', 't', 'u', 'p', 'M', 'o', 'd', 'e', 0 };
+ efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
efi_get_variable_t *f_getvar = sys_table_arg->runtime->get_variable;
- unsigned long size = sizeof(u8);
- efi_status_t status;
u8 val;
+ unsigned long size = sizeof(val);
+ efi_status_t status;
- status = f_getvar((efi_char16_t *)var_name, (efi_guid_t *)&var_guid,
+ status = f_getvar((efi_char16_t *)sb_var_name, (efi_guid_t *)&var_guid,
NULL, &size, &val);
+ if (status != EFI_SUCCESS)
+ goto out_efi_err;
+
+ if (val == 0)
+ return 0;
+
+ status = f_getvar((efi_char16_t *)sm_var_name, (efi_guid_t *)&var_guid,
+ NULL, &size, &val);
+
+ if (status != EFI_SUCCESS)
+ goto out_efi_err;
+
+ if (val == 1)
+ return 0;
+
+ return 1;
+
+out_efi_err:
switch (status) {
- case EFI_SUCCESS:
- return val;
case EFI_NOT_FOUND:
return 0;
case EFI_DEVICE_ERROR:
