On 1/19/2021 3:06 AM, Borislav Petkov wrote:
On Tue, Dec 29, 2020 at 01:30:29PM -0800, Yu-cheng Yu wrote:
Shadow Stack provides protection against function return address
corruption. It is active when the processor supports it, the kernel has
CONFIG_X86_CET_USER enabled, and the application is built for the feature.
This is only implemented for the 64-bit kernel. When it is enabled, legacy
non-Shadow Stack applications continue to work, but without protection.
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
---
arch/x86/Kconfig | 22 ++++++++++++++++++++++
arch/x86/Kconfig.assembler | 5 +++++
2 files changed, 27 insertions(+)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7b6dd10b162a..72cff400b9ae 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1950,6 +1950,28 @@ config X86_SGX
If unsure, say N.
+config ARCH_HAS_SHADOW_STACK
+ def_bool n
+
+config X86_CET_USER
That thing needs to be X86_CET. How many times do I need to type this
before you do it?
Yes, I totally understand that now. I was still thinking about
separately enabling user/kernel mode. Perhaps I should have
communicated that thought before the change. Sorry about that. I will
update it.
--
Yu-cheng