From: Sami Tolvanen <samitolvanen@google.com>
Date: Mon, 27 Apr 2020 16:00:14 +0000 (-0700)
Subject: arm64: vdso: Disable Shadow Call Stack
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=cde5dec89e5dee5a6de12cd99fdb24651ee03146;p=linux.git

arm64: vdso: Disable Shadow Call Stack

Shadow stacks are only available in the kernel, so disable SCS
instrumentation for the vDSO.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
---

diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index dd2514bb1511f..a87a4f11724e4 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -25,7 +25,7 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING
 
 VDSO_LDFLAGS := -Bsymbolic
 
-CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS)
 KBUILD_CFLAGS			+= $(DISABLE_LTO)
 KASAN_SANITIZE			:= n
 UBSAN_SANITIZE			:= n