diff options
| author | Matthew Garrett <mjg59@google.com> | 2017-08-25 16:50:15 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-08-26 09:20:33 +0200 |
| commit | ccc829ba3624beb9a703fc995d016b836d9eead8 (patch) | |
| tree | b1791e31decb96c4fad4cd24b6b9dce5a351d2eb /include/linux/efi.h | |
| parent | 3cb9bc85029f2ceb7a5babadcab445c7cb861da8 (diff) | |
efi/libstub: Enable reset attack mitigation
If a machine is reset while secrets are present in RAM, it may be
possible for code executed after the reboot to extract those secrets
from untouched memory. The Trusted Computing Group specified a mechanism
for requesting that the firmware clear all RAM on reset before booting
another OS. This is done by setting the MemoryOverwriteRequestControl
variable at startup. If userspace can ensure that all secrets are
removed as part of a controlled shutdown, it can reset this variable to
0 before triggering a hardware reboot.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/efi.h')
| -rw-r--r-- | include/linux/efi.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/efi.h b/include/linux/efi.h index 4e47f78430be..c241acca0b15 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1504,6 +1504,13 @@ enum efi_secureboot_mode { }; enum efi_secureboot_mode efi_get_secureboot(efi_system_table_t *sys_table); +#ifdef CONFIG_RESET_ATTACK_MITIGATION +void efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg); +#else +static inline void +efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg) { } +#endif + /* * Arch code can implement the following three template macros, avoiding * reptition for the void/non-void return cases of {__,}efi_call_virt(): |