diff options
| author | Sami Tolvanen <samitolvanen@google.com> | 2018-05-02 09:41:34 -0700 |
|---|---|---|
| committer | Sami Tolvanen <samitolvanen@google.com> | 2019-12-13 07:14:20 -0800 |
| commit | fb8319c10d6e6ae5c3b794675a49b5a096208c25 (patch) | |
| tree | 78b2a3e536e8fa02d3096758a059ab07948f1a22 /arch | |
| parent | 1425ea0ab86f43e235d9081852165ab8ef003346 (diff) | |
FROMLIST: arm64: reserve x18 from general allocation with SCS
Reserve the x18 register from general allocation when SCS is enabled,
because the compiler uses the register to store the current task's
shadow stack pointer. Note that all external kernel modules must also be
compiled with -ffixed-x18 if the kernel has SCS enabled.
Bug: 145210207
Change-Id: If2315ace9a879b3dd2a85f6ba43eddadc4430595
(am from https://lore.kernel.org/patchwork/patch/1149058/)
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/Makefile | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 8654cee8c921..79650bfbbfd9 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -74,6 +74,10 @@ KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) +ifeq ($(CONFIG_SHADOW_CALL_STACK), y) +KBUILD_CFLAGS += -ffixed-x18 +endif + ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) KBUILD_CPPFLAGS += -mbig-endian CHECKFLAGS += -D__AARCH64EB__ |