As of rustc 1.80.0, the Rust compiler supports the -Zfixed-x18 flag, so we can now use Rust with the shadow call stack sanitizer. On older versions of Rust, it is possible to use shadow call stack by passing -Ctarget-feature=+reserve-x18 instead of -Zfixed-x18. However, this flag emits a warning, so this patch does not add support for that. Currently, the compiler thinks that the aarch64-unknown-none target doesn't support -Zsanitizer=shadow-call-stack, so the build will fail if you enable shadow call stack in non-dynamic mode. See [2] for the feature request to add this. Kconfig is not configured to reject this configuration because that leads to cyclic Kconfig rules. Link: https://github.com/rust-lang/rust/issues/121972 [1] Signed-off-by: Alice Ryhl <aliceryhl@xxxxxxxxxx> --- Makefile | 1 + arch/Kconfig | 2 +- arch/arm64/Makefile | 3 +++ 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index c11a10c8e710..4ae741601a1c 100644 --- a/Makefile +++ b/Makefile @@ -945,6 +945,7 @@ ifdef CONFIG_SHADOW_CALL_STACK ifndef CONFIG_DYNAMIC_SCS CC_FLAGS_SCS := -fsanitize=shadow-call-stack KBUILD_CFLAGS += $(CC_FLAGS_SCS) +KBUILD_RUSTFLAGS += -Zsanitizer=shadow-call-stack endif export CC_FLAGS_SCS endif diff --git a/arch/Kconfig b/arch/Kconfig index 238448a9cb71..5a6e296df5e6 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -690,7 +690,7 @@ config SHADOW_CALL_STACK bool "Shadow Call Stack" depends on ARCH_SUPPORTS_SHADOW_CALL_STACK depends on DYNAMIC_FTRACE_WITH_ARGS || DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER - depends on !RUST + depends on !RUST || RUSTC_VERSION >= 108000 depends on MMU help This option enables the compiler's Shadow Call Stack, which diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 3f0f35fd5bb7..bbf313ddd700 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -57,9 +57,11 @@ KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) ifneq ($(CONFIG_UNWIND_TABLES),y) KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables +KBUILD_RUSTFLAGS += -Cforce-unwind-tables=n else KBUILD_CFLAGS += -fasynchronous-unwind-tables KBUILD_AFLAGS += -fasynchronous-unwind-tables +KBUILD_RUSTFLAGS += -Cforce-unwind-tables=y -Zuse-sync-unwind=n endif ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) @@ -114,6 +116,7 @@ endif ifeq ($(CONFIG_SHADOW_CALL_STACK), y) KBUILD_CFLAGS += -ffixed-x18 +KBUILD_RUSTFLAGS += -Zfixed-x18 endif ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) -- 2.45.2.803.g4e1b14247a-goog
