[PATCH v10 26/40] arm64: Add Kconfig for Guarded Control Stack (GCS)

Mark Brown
2024-08-01T13:00:22Z

Provide a Kconfig option allowing the user to select if GCS support is
built into the kernel.

Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
arch/arm64/Kconfig | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b3fc891f1544..83e27857bc6a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -2127,6 +2127,26 @@ config ARM64_EPAN
if the cpu does not implement the feature.
endmenu # "ARMv8.7 architectural features"

+menu "v9.4 architectural features"
+
+config ARM64_GCS
+ bool "Enable support for Guarded Control Stack (GCS)"
+ default y
+ select ARCH_HAS_USER_SHADOW_STACK
+ select ARCH_USES_HIGH_VMA_FLAGS
+ help
+ Guarded Control Stack (GCS) provides support for a separate
+ stack with restricted access which contains only return
+ addresses. This can be used to harden against some attacks
+ by comparing return address used by the program with what is
+ stored in the GCS, and may also be used to efficiently obtain
+ the call stack for applications such as profiling.
+
+ The feature is detected at runtime, and will remain disabled
+ if the system does not implement the feature.
+
+endmenu # "v9.4 architectural features"
+
config ARM64_SVE
bool "ARM Scalable Vector Extension support"
default y

--
2.39.2