[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20200128184934.77625-6-samitolvanen@google.com>
Date: Tue, 28 Jan 2020 10:49:28 -0800
From: Sami Tolvanen <samitolvanen@...gle.com>
To: Will Deacon <will@...nel.org>, Catalin Marinas <catalin.marinas@....com>,
Steven Rostedt <rostedt@...dmis.org>, Masami Hiramatsu <mhiramat@...nel.org>,
Ard Biesheuvel <ard.biesheuvel@...aro.org>, Mark Rutland <mark.rutland@....com>, james.morse@....com
Cc: Dave Martin <Dave.Martin@....com>, Kees Cook <keescook@...omium.org>,
Laura Abbott <labbott@...hat.com>, Marc Zyngier <maz@...nel.org>,
Nick Desaulniers <ndesaulniers@...gle.com>, Jann Horn <jannh@...gle.com>,
Miguel Ojeda <miguel.ojeda.sandonis@...il.com>,
Masahiro Yamada <yamada.masahiro@...ionext.com>, clang-built-linux@...glegroups.com,
kernel-hardening@...ts.openwall.com, linux-arm-kernel@...ts.infradead.org,
linux-kernel@...r.kernel.org, Sami Tolvanen <samitolvanen@...gle.com>
Subject: [PATCH v7 05/11] 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.
Signed-off-by: Sami Tolvanen <samitolvanen@...gle.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@...gle.com>
Reviewed-by: Kees Cook <keescook@...omium.org>
Acked-by: Will Deacon <will@...nel.org>
---
arch/arm64/Makefile | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index dca1a97751ab..ab26b448faa9 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -65,6 +65,10 @@ stack_protector_prepare: prepare0
include/generated/asm-offsets.h))
endif
+ifeq ($(CONFIG_SHADOW_CALL_STACK), y)
+KBUILD_CFLAGS += -ffixed-x18
+endif
+
ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
KBUILD_CPPFLAGS += -mbig-endian
CHECKFLAGS += -D__AARCH64EB__
--
2.25.0.341.g760bfbb309-goog
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
