From 613f4b3ed7902d1dbbc6ade6401e452a63dfbc21 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 3 May 2022 13:55:01 -0700 Subject: [PATCH] randstruct: Split randstruct Makefile and CFLAGS To enable the new Clang randstruct implementation[1], move randstruct into its own Makefile and split the CFLAGS from GCC_PLUGINS_CFLAGS into RANDSTRUCT_CFLAGS. [1] https://reviews.llvm.org/D121556 Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220503205503.3054173-5-keescook@chromium.org --- Makefile | 1 + arch/arm/vdso/Makefile | 2 +- arch/arm64/kernel/vdso/Makefile | 3 ++- arch/sparc/vdso/Makefile | 3 ++- arch/x86/entry/vdso/Makefile | 3 ++- scripts/Makefile.gcc-plugins | 8 ++------ scripts/Makefile.randstruct | 14 ++++++++++++++ 7 files changed, 24 insertions(+), 10 deletions(-) create mode 100644 scripts/Makefile.randstruct diff --git a/Makefile b/Makefile index 29e273d3f8cc..91c91fcf3c24 100644 --- a/Makefile +++ b/Makefile @@ -1011,6 +1011,7 @@ include-$(CONFIG_KASAN) += scripts/Makefile.kasan include-$(CONFIG_KCSAN) += scripts/Makefile.kcsan include-$(CONFIG_UBSAN) += scripts/Makefile.ubsan include-$(CONFIG_KCOV) += scripts/Makefile.kcov +include-$(CONFIG_RANDSTRUCT) += scripts/Makefile.randstruct include-$(CONFIG_GCC_PLUGINS) += scripts/Makefile.gcc-plugins include $(addprefix $(srctree)/, $(include-y)) diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile index ec52b776f926..8ca1c9f262a2 100644 --- a/arch/arm/vdso/Makefile +++ b/arch/arm/vdso/Makefile @@ -28,7 +28,7 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) CFLAGS_REMOVE_vdso.o = -pg # Force -O2 to avoid libgcc dependencies -CFLAGS_REMOVE_vgettimeofday.o = -pg -Os $(GCC_PLUGINS_CFLAGS) +CFLAGS_REMOVE_vgettimeofday.o = -pg -Os $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) ifeq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday.o = -O2 else diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index 172452f79e46..d9147fba1a0b 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -32,7 +32,8 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO # -Wmissing-prototypes and -Wmissing-declarations are removed from # the CFLAGS of vgettimeofday.c to make possible to build the # kernel with CONFIG_WERROR enabled. -CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS) \ +CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \ + $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \ $(CC_FLAGS_LTO) -Wmissing-prototypes -Wmissing-declarations KASAN_SANITIZE := n KCSAN_SANITIZE := n diff --git a/arch/sparc/vdso/Makefile b/arch/sparc/vdso/Makefile index c5e1545bc5cf..77d7b9032158 100644 --- a/arch/sparc/vdso/Makefile +++ b/arch/sparc/vdso/Makefile @@ -58,7 +58,7 @@ CFL := $(PROFILING) -mcmodel=medlow -fPIC -O2 -fasynchronous-unwind-tables -m64 SPARC_REG_CFLAGS = -ffixed-g4 -ffixed-g5 -fcall-used-g5 -fcall-used-g7 -$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(SPARC_REG_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +$(vobjs): KBUILD_CFLAGS := $(filter-out $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(SPARC_REG_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. @@ -88,6 +88,7 @@ $(obj)/vdso32.so.dbg: asflags-$(CONFIG_SPARC64) += -m32 KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) KBUILD_CFLAGS_32 := $(filter-out -mcmodel=medlow,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out $(RANDSTRUCT_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(SPARC_REG_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 += -m32 -msoft-float -fpic diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 693f8b9031fb..c2a8b76ae0bc 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -91,7 +91,7 @@ ifneq ($(RETPOLINE_VDSO_CFLAGS),) endif endif -$(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +$(vobjs): KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO) $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. @@ -148,6 +148,7 @@ KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS)) KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out $(RANDSTRUCT_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS_32)) diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 827c47ce5c73..692d64a70542 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -22,12 +22,6 @@ export DISABLE_STRUCTLEAK_PLUGIN gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) \ += -DSTRUCTLEAK_PLUGIN -gcc-plugin-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) += randomize_layout_plugin.so -gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) \ - += -DRANDSTRUCT -gcc-plugin-cflags-$(CONFIG_RANDSTRUCT_PERFORMANCE) \ - += -fplugin-arg-randomize_layout_plugin-performance-mode - gcc-plugin-$(CONFIG_GCC_PLUGIN_STACKLEAK) += stackleak_plugin.so gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STACKLEAK) \ += -DSTACKLEAK_PLUGIN @@ -60,6 +54,8 @@ KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) # be included in GCC_PLUGIN so they can get built. gcc-plugin-external-$(CONFIG_GCC_PLUGIN_SANCOV) \ += sancov_plugin.so +gcc-plugin-external-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) \ + += randomize_layout_plugin.so # All enabled GCC plugins are collected here for building in # scripts/gcc-scripts/Makefile. diff --git a/scripts/Makefile.randstruct b/scripts/Makefile.randstruct new file mode 100644 index 000000000000..4d741e6db554 --- /dev/null +++ b/scripts/Makefile.randstruct @@ -0,0 +1,14 @@ +# SPDX-License-Identifier: GPL-2.0 + +randstruct-cflags-y += -DRANDSTRUCT + +ifdef CONFIG_GCC_PLUGIN_RANDSTRUCT +randstruct-cflags-y \ + += -fplugin=$(objtree)/scripts/gcc-plugins/randomize_layout_plugin.so +randstruct-cflags-$(CONFIG_RANDSTRUCT_PERFORMANCE) \ + += -fplugin-arg-randomize_layout_plugin-performance-mode +endif + +export RANDSTRUCT_CFLAGS := $(randstruct-cflags-y) + +KBUILD_CFLAGS += $(RANDSTRUCT_CFLAGS)