From 6b90bd4ba40b38dc13c2782469c1c77e4ed79915 Mon Sep 17 00:00:00 2001 From: Emese Revfy Date: Tue, 24 May 2016 00:09:38 +0200 Subject: GCC plugin infrastructure This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy Acked-by: Kees Cook Signed-off-by: Michal Marek --- scripts/Makefile.gcc-plugins | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 scripts/Makefile.gcc-plugins (limited to 'scripts/Makefile.gcc-plugins') diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins new file mode 100644 index 000000000000..bcc373dcb3b5 --- /dev/null +++ b/scripts/Makefile.gcc-plugins @@ -0,0 +1,23 @@ +ifdef CONFIG_GCC_PLUGINS + __PLUGINCC := $(call cc-ifversion, -ge, 0408, $(HOSTCXX), $(HOSTCC)) + PLUGINCC := $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") + + GCC_PLUGINS_CFLAGS := $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) + + export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN + + ifeq ($(PLUGINCC),) + ifneq ($(GCC_PLUGINS_CFLAGS),) + ifeq ($(call cc-ifversion, -ge, 0405, y), y) + PLUGINCC := $(shell $(CONFIG_SHELL) -x $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") + $(warning warning: your gcc installation does not support plugins, perhaps the necessary headers are missing?) + else + $(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least) + endif + endif + endif + + KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) + GCC_PLUGIN := $(gcc-plugin-y) + +endif -- cgit v1.2.3 From 0dae776c6bf31e779c172753f6e2d6426eb42523 Mon Sep 17 00:00:00 2001 From: Emese Revfy Date: Tue, 24 May 2016 00:10:35 +0200 Subject: Add Cyclomatic complexity GCC plugin Add a very simple plugin to demonstrate the GCC plugin infrastructure. This GCC plugin computes the cyclomatic complexity of each function. The complexity M of a function's control flow graph is defined as: M = E - N + 2P where E = the number of edges N = the number of nodes P = the number of connected components (exit nodes). Signed-off-by: Emese Revfy Acked-by: Kees Cook Signed-off-by: Michal Marek --- arch/Kconfig | 12 +++++ scripts/Makefile.gcc-plugins | 1 + scripts/gcc-plugins/Makefile | 1 + scripts/gcc-plugins/cyc_complexity_plugin.c | 73 +++++++++++++++++++++++++++++ 4 files changed, 87 insertions(+) create mode 100644 scripts/gcc-plugins/cyc_complexity_plugin.c (limited to 'scripts/Makefile.gcc-plugins') diff --git a/arch/Kconfig b/arch/Kconfig index 1b93632198fa..04ca45262ad1 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -372,6 +372,18 @@ menuconfig GCC_PLUGINS See Documentation/gcc-plugins.txt for details. +config GCC_PLUGIN_CYC_COMPLEXITY + bool "Compute the cyclomatic complexity of a function" + depends on GCC_PLUGINS + help + The complexity M of a function's control flow graph is defined as: + M = E - N + 2P + where + + E = the number of edges + N = the number of nodes + P = the number of connected components (exit nodes). + config HAVE_CC_STACKPROTECTOR bool help diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index bcc373dcb3b5..b4a189c95a8a 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -2,6 +2,7 @@ ifdef CONFIG_GCC_PLUGINS __PLUGINCC := $(call cc-ifversion, -ge, 0408, $(HOSTCXX), $(HOSTCC)) PLUGINCC := $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") + gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so GCC_PLUGINS_CFLAGS := $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index a4c93419d5d1..c60ba4bef57c 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -17,4 +17,5 @@ export GCCPLUGINS_DIR HOSTLIBS $(HOSTLIBS)-y := $(GCC_PLUGIN) always := $($(HOSTLIBS)-y) +cyc_complexity_plugin-objs := cyc_complexity_plugin.o clean-files += *.so diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c new file mode 100644 index 000000000000..34df974c6ba3 --- /dev/null +++ b/scripts/gcc-plugins/cyc_complexity_plugin.c @@ -0,0 +1,73 @@ +/* + * Copyright 2011-2016 by Emese Revfy + * Licensed under the GPL v2, or (at your option) v3 + * + * Homepage: + * https://github.com/ephox-gcc-plugins/cyclomatic_complexity + * + * http://en.wikipedia.org/wiki/Cyclomatic_complexity + * The complexity M is then defined as: + * M = E - N + 2P + * where + * + * E = the number of edges of the graph + * N = the number of nodes of the graph + * P = the number of connected components (exit nodes). + * + * Usage (4.5 - 5): + * $ make clean; make run + */ + +#include "gcc-common.h" + +int plugin_is_GPL_compatible; + +static struct plugin_info cyc_complexity_plugin_info = { + .version = "20160225", + .help = "Cyclomatic Complexity\n", +}; + +static unsigned int cyc_complexity_execute(void) +{ + int complexity; + expanded_location xloc; + + /* M = E - N + 2P */ + complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2; + + xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl)); + fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity, + xloc.file, DECL_NAME_POINTER(current_function_decl)); + + return 0; +} + +#define PASS_NAME cyc_complexity + +#define NO_GATE +#define TODO_FLAGS_FINISH TODO_dump_func + +#include "gcc-generate-gimple-pass.h" + +int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version) +{ + const char * const plugin_name = plugin_info->base_name; + struct register_pass_info cyc_complexity_pass_info; + + cyc_complexity_pass_info.pass = make_cyc_complexity_pass(); + cyc_complexity_pass_info.reference_pass_name = "ssa"; + cyc_complexity_pass_info.ref_pass_instance_number = 1; + cyc_complexity_pass_info.pos_op = PASS_POS_INSERT_AFTER; + + if (!plugin_default_version_check(version, &gcc_version)) { + error(G_("incompatible gcc/plugin versions")); + return 1; + } + + register_callback(plugin_name, PLUGIN_INFO, NULL, + &cyc_complexity_plugin_info); + register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL, + &cyc_complexity_pass_info); + + return 0; +} -- cgit v1.2.3 From 543c37cb165049c3be24a0d4733e67caa2b33eef Mon Sep 17 00:00:00 2001 From: Emese Revfy Date: Tue, 24 May 2016 00:11:37 +0200 Subject: Add sancov plugin The sancov gcc plugin inserts a __sanitizer_cov_trace_pc() call at the start of basic blocks. This plugin is a helper plugin for the kcov feature. It supports all gcc versions with plugin support (from gcc-4.5 on). It is based on the gcc commit "Add fuzzing coverage support" by Dmitry Vyukov (https://gcc.gnu.org/viewcvs/gcc?limit_changes=0&view=revision&revision=231296). Signed-off-by: Emese Revfy Acked-by: Kees Cook Signed-off-by: Michal Marek --- Makefile | 10 +-- arch/Kconfig | 9 +++ arch/x86/purgatory/Makefile | 2 + lib/Kconfig.debug | 2 + scripts/Makefile.gcc-plugins | 21 +++++- scripts/gcc-plugins/Makefile | 6 ++ scripts/gcc-plugins/sancov_plugin.c | 144 ++++++++++++++++++++++++++++++++++++ 7 files changed, 184 insertions(+), 10 deletions(-) create mode 100644 scripts/gcc-plugins/sancov_plugin.c (limited to 'scripts/Makefile.gcc-plugins') diff --git a/Makefile b/Makefile index 20fcf4b26fbc..c3d494ba3ae1 100644 --- a/Makefile +++ b/Makefile @@ -369,7 +369,7 @@ LDFLAGS_MODULE = CFLAGS_KERNEL = AFLAGS_KERNEL = CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im -Wno-maybe-uninitialized -CFLAGS_KCOV = -fsanitize-coverage=trace-pc +CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,) # Use USERINCLUDE when you must reference the UAPI directories only. @@ -691,14 +691,6 @@ endif endif KBUILD_CFLAGS += $(stackp-flag) -ifdef CONFIG_KCOV - ifeq ($(call cc-option, $(CFLAGS_KCOV)),) - $(warning Cannot use CONFIG_KCOV: \ - -fsanitize-coverage=trace-pc is not supported by compiler) - CFLAGS_KCOV = - endif -endif - ifeq ($(cc-name),clang) KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,) diff --git a/arch/Kconfig b/arch/Kconfig index 04ca45262ad1..05f1e95b796d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -384,6 +384,15 @@ config GCC_PLUGIN_CYC_COMPLEXITY N = the number of nodes P = the number of connected components (exit nodes). +config GCC_PLUGIN_SANCOV + bool + depends on GCC_PLUGINS + help + This plugin inserts a __sanitizer_cov_trace_pc() call at the start of + basic blocks. It supports all gcc versions with plugin support (from + gcc-4.5 on). It is based on the commit "Add fuzzing coverage support" + by Dmitry Vyukov . + config HAVE_CC_STACKPROTECTOR bool help diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile index 12734a96df47..ac58c1616408 100644 --- a/arch/x86/purgatory/Makefile +++ b/arch/x86/purgatory/Makefile @@ -8,6 +8,8 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y)) LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib targets += purgatory.ro +KCOV_INSTRUMENT := n + # Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That # in turn leaves some undefined symbols like __fentry__ in purgatory and not # sure how to relocate those. Like kexec-tools, use custom flags. diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 77d7d034bac3..b7827dca3fec 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -708,6 +708,8 @@ config KCOV bool "Code coverage for fuzzing" depends on ARCH_HAS_KCOV select DEBUG_FS + select GCC_PLUGINS + select GCC_PLUGIN_SANCOV help KCOV exposes kernel code coverage information in a form suitable for coverage-guided fuzzing (randomized testing). diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index b4a189c95a8a..5e22b60589c1 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -2,10 +2,26 @@ ifdef CONFIG_GCC_PLUGINS __PLUGINCC := $(call cc-ifversion, -ge, 0408, $(HOSTCXX), $(HOSTCC)) PLUGINCC := $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") + SANCOV_PLUGIN := -fplugin=$(objtree)/scripts/gcc-plugins/sancov_plugin.so + gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so + + ifdef CONFIG_GCC_PLUGIN_SANCOV + ifeq ($(CFLAGS_KCOV),) + # It is needed because of the gcc-plugin.sh and gcc version checks. + gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV) += sancov_plugin.so + + ifneq ($(PLUGINCC),) + CFLAGS_KCOV := $(SANCOV_PLUGIN) + else + $(warning warning: cannot use CONFIG_KCOV: -fsanitize-coverage=trace-pc is not supported by compiler) + endif + endif + endif + GCC_PLUGINS_CFLAGS := $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) - export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN + export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN ifeq ($(PLUGINCC),) ifneq ($(GCC_PLUGINS_CFLAGS),) @@ -16,6 +32,9 @@ ifdef CONFIG_GCC_PLUGINS $(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least) endif endif + else + # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. + GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) endif KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index c60ba4bef57c..88c8ec47232b 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -14,8 +14,14 @@ endif export GCCPLUGINS_DIR HOSTLIBS +ifneq ($(CFLAGS_KCOV), $(SANCOV_PLUGIN)) + GCC_PLUGIN := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGIN)) +endif + $(HOSTLIBS)-y := $(GCC_PLUGIN) always := $($(HOSTLIBS)-y) cyc_complexity_plugin-objs := cyc_complexity_plugin.o +sancov_plugin-objs := sancov_plugin.o + clean-files += *.so diff --git a/scripts/gcc-plugins/sancov_plugin.c b/scripts/gcc-plugins/sancov_plugin.c new file mode 100644 index 000000000000..aedd6113cb73 --- /dev/null +++ b/scripts/gcc-plugins/sancov_plugin.c @@ -0,0 +1,144 @@ +/* + * Copyright 2011-2016 by Emese Revfy + * Licensed under the GPL v2, or (at your option) v3 + * + * Homepage: + * https://github.com/ephox-gcc-plugins/sancov + * + * This plugin inserts a __sanitizer_cov_trace_pc() call at the start of basic blocks. + * It supports all gcc versions with plugin support (from gcc-4.5 on). + * It is based on the commit "Add fuzzing coverage support" by Dmitry Vyukov . + * + * You can read about it more here: + * https://gcc.gnu.org/viewcvs/gcc?limit_changes=0&view=revision&revision=231296 + * http://lwn.net/Articles/674854/ + * https://github.com/google/syzkaller + * https://lwn.net/Articles/677764/ + * + * Usage: + * make run + */ + +#include "gcc-common.h" + +int plugin_is_GPL_compatible; + +tree sancov_fndecl; + +static struct plugin_info sancov_plugin_info = { + .version = "20160402", + .help = "sancov plugin\n", +}; + +static unsigned int sancov_execute(void) +{ + basic_block bb; + + /* Remove this line when this plugin and kcov will be in the kernel. + if (!strcmp(DECL_NAME_POINTER(current_function_decl), DECL_NAME_POINTER(sancov_fndecl))) + return 0; + */ + + FOR_EACH_BB_FN(bb, cfun) { + const_gimple stmt; + gcall *gcall; + gimple_stmt_iterator gsi = gsi_after_labels(bb); + + if (gsi_end_p(gsi)) + continue; + + stmt = gsi_stmt(gsi); + gcall = as_a_gcall(gimple_build_call(sancov_fndecl, 0)); + gimple_set_location(gcall, gimple_location(stmt)); + gsi_insert_before(&gsi, gcall, GSI_SAME_STMT); + } + return 0; +} + +#define PASS_NAME sancov + +#define NO_GATE +#define TODO_FLAGS_FINISH TODO_dump_func | TODO_verify_stmts | TODO_update_ssa_no_phi | TODO_verify_flow + +#include "gcc-generate-gimple-pass.h" + +static void sancov_start_unit(void __unused *gcc_data, void __unused *user_data) +{ + tree leaf_attr, nothrow_attr; + tree BT_FN_VOID = build_function_type_list(void_type_node, NULL_TREE); + + sancov_fndecl = build_fn_decl("__sanitizer_cov_trace_pc", BT_FN_VOID); + + DECL_ASSEMBLER_NAME(sancov_fndecl); + TREE_PUBLIC(sancov_fndecl) = 1; + DECL_EXTERNAL(sancov_fndecl) = 1; + DECL_ARTIFICIAL(sancov_fndecl) = 1; + DECL_PRESERVE_P(sancov_fndecl) = 1; + DECL_UNINLINABLE(sancov_fndecl) = 1; + TREE_USED(sancov_fndecl) = 1; + + nothrow_attr = tree_cons(get_identifier("nothrow"), NULL, NULL); + decl_attributes(&sancov_fndecl, nothrow_attr, 0); + gcc_assert(TREE_NOTHROW(sancov_fndecl)); +#if BUILDING_GCC_VERSION > 4005 + leaf_attr = tree_cons(get_identifier("leaf"), NULL, NULL); + decl_attributes(&sancov_fndecl, leaf_attr, 0); +#endif +} + +int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version) +{ + int i; + struct register_pass_info sancov_plugin_pass_info; + const char * const plugin_name = plugin_info->base_name; + const int argc = plugin_info->argc; + const struct plugin_argument * const argv = plugin_info->argv; + bool enable = true; + + static const struct ggc_root_tab gt_ggc_r_gt_sancov[] = { + { + .base = &sancov_fndecl, + .nelt = 1, + .stride = sizeof(sancov_fndecl), + .cb = >_ggc_mx_tree_node, + .pchw = >_pch_nx_tree_node + }, + LAST_GGC_ROOT_TAB + }; + + /* BBs can be split afterwards?? */ + sancov_plugin_pass_info.pass = make_sancov_pass(); +#if BUILDING_GCC_VERSION >= 4009 + sancov_plugin_pass_info.reference_pass_name = "asan"; +#else + sancov_plugin_pass_info.reference_pass_name = "nrv"; +#endif + sancov_plugin_pass_info.ref_pass_instance_number = 0; + sancov_plugin_pass_info.pos_op = PASS_POS_INSERT_BEFORE; + + if (!plugin_default_version_check(version, &gcc_version)) { + error(G_("incompatible gcc/plugin versions")); + return 1; + } + + for (i = 0; i < argc; ++i) { + if (!strcmp(argv[i].key, "no-sancov")) { + enable = false; + continue; + } + error(G_("unkown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key); + } + + register_callback(plugin_name, PLUGIN_INFO, NULL, &sancov_plugin_info); + + if (!enable) + return 0; + +#if BUILDING_GCC_VERSION < 6000 + register_callback(plugin_name, PLUGIN_START_UNIT, &sancov_start_unit, NULL); + register_callback(plugin_name, PLUGIN_REGISTER_GGC_ROOTS, NULL, (void *)>_ggc_r_gt_sancov); + register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL, &sancov_plugin_pass_info); +#endif + + return 0; +} -- cgit v1.2.3 From ed58c0e9eefef517aa5a547b78658e2ab4422232 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 17 Jun 2016 23:11:12 -0700 Subject: gcc-plugins: abort builds cleanly when not supported When the compiler doesn't support gcc plugins (either due to missing headers or too old a version), report the problem and abort the build instead of emitting a warning and letting the build founder with arcane compiler errors. Signed-off-by: Kees Cook --- Makefile | 7 ------- scripts/Makefile.gcc-plugins | 34 +++++++++++++++++++++++++--------- scripts/gcc-plugin.sh | 14 ++++++++++++++ 3 files changed, 39 insertions(+), 16 deletions(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/Makefile b/Makefile index 70de1448c571..8c504f324154 100644 --- a/Makefile +++ b/Makefile @@ -635,13 +635,6 @@ endif # Tell gcc to never replace conditional load with a non-conditional one KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0) -PHONY += gcc-plugins -gcc-plugins: scripts_basic -ifdef CONFIG_GCC_PLUGINS - $(Q)$(MAKE) $(build)=scripts/gcc-plugins -endif - @: - include scripts/Makefile.gcc-plugins ifdef CONFIG_READABLE_ASM diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 5e22b60589c1..bbca1f46f6e4 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -23,21 +23,37 @@ ifdef CONFIG_GCC_PLUGINS export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN + ifneq ($(PLUGINCC),) + # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. + GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) + endif + + KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) + GCC_PLUGIN := $(gcc-plugin-y) +endif + +# If plugins aren't supported, abort the build before hard-to-read compiler +# errors start getting spewed by the main build. +PHONY += gcc-plugins-check +gcc-plugins-check: FORCE +ifdef CONFIG_GCC_PLUGINS ifeq ($(PLUGINCC),) ifneq ($(GCC_PLUGINS_CFLAGS),) ifeq ($(call cc-ifversion, -ge, 0405, y), y) - PLUGINCC := $(shell $(CONFIG_SHELL) -x $(srctree)/scripts/gcc-plugin.sh "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)") - $(warning warning: your gcc installation does not support plugins, perhaps the necessary headers are missing?) + $(Q)$(srctree)/scripts/gcc-plugin.sh --show-error "$(__PLUGINCC)" "$(HOSTCXX)" "$(CC)" || true + @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc installation does not support plugins, perhaps the necessary headers are missing?" >&2 && exit 1 else - $(warning warning: your gcc version does not support plugins, you should upgrade it to gcc 4.5 at least) + @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc version does not support plugins, you should upgrade it to at least gcc 4.5" >&2 && exit 1 endif endif - else - # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. - GCC_PLUGINS_CFLAGS := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGINS_CFLAGS)) endif +endif + @: - KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) - GCC_PLUGIN := $(gcc-plugin-y) - +# Actually do the build, if requested. +PHONY += gcc-plugins +gcc-plugins: scripts_basic gcc-plugins-check +ifdef CONFIG_GCC_PLUGINS + $(Q)$(MAKE) $(build)=scripts/gcc-plugins endif + @: diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh index fb9207565471..b65224bfb847 100755 --- a/scripts/gcc-plugin.sh +++ b/scripts/gcc-plugin.sh @@ -1,5 +1,12 @@ #!/bin/sh srctree=$(dirname "$0") + +SHOW_ERROR= +if [ "$1" = "--show-error" ] ; then + SHOW_ERROR=1 + shift || true +fi + gccplugins_dir=$($3 -print-file-name=plugin) plugincc=$($1 -E -x c++ - -o /dev/null -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <&2 + fi exit 1 fi @@ -48,4 +58,8 @@ then echo "$2" exit 0 fi + +if [ -n "$SHOW_ERROR" ] ; then + echo "${plugincc}" >&2 +fi exit 1 -- cgit v1.2.3 From 65d59ec8ad99e9d932ccca4daabb8e3fdafeb11b Mon Sep 17 00:00:00 2001 From: Emese Revfy Date: Mon, 20 Jun 2016 20:40:24 +0200 Subject: gcc-plugins: Add support for passing plugin arguments The latent_entropy plugin needs to pass arguments, so this adds the support. Signed-off-by: Emese Revfy Signed-off-by: Kees Cook --- scripts/Makefile.gcc-plugins | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index bbca1f46f6e4..ffb928b9c74b 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -19,7 +19,7 @@ ifdef CONFIG_GCC_PLUGINS endif endif - GCC_PLUGINS_CFLAGS := $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) + GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y)) export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN -- cgit v1.2.3 From caefd8c9a9fb06811e07bf3571e5d4450846b16a Mon Sep 17 00:00:00 2001 From: Emese Revfy Date: Sun, 26 Jun 2016 17:38:20 +0200 Subject: gcc-plugins: Add support for plugin subdirectories This adds support for building more complex gcc plugins that live in a subdirectory instead of just in a single source file. Reported-by: PaX Team Signed-off-by: Emese Revfy [kees: clarified commit message] Signed-off-by: Kees Cook --- scripts/Makefile.gcc-plugins | 3 ++- scripts/gcc-plugins/Makefile | 9 ++++++--- 2 files changed, 8 insertions(+), 4 deletions(-) (limited to 'scripts/Makefile.gcc-plugins') diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index ffb928b9c74b..61f0e6db909b 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -21,7 +21,7 @@ ifdef CONFIG_GCC_PLUGINS GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y)) - export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN SANCOV_PLUGIN + export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR SANCOV_PLUGIN ifneq ($(PLUGINCC),) # SANCOV_PLUGIN can be only in CFLAGS_KCOV because avoid duplication. @@ -30,6 +30,7 @@ ifdef CONFIG_GCC_PLUGINS KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS) GCC_PLUGIN := $(gcc-plugin-y) + GCC_PLUGIN_SUBDIR := $(gcc-plugin-subdir-y) endif # If plugins aren't supported, abort the build before hard-to-read compiler diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index ee0a75d2a1c7..8b29dc17c73c 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -12,15 +12,18 @@ else export HOST_EXTRACXXFLAGS endif -export GCCPLUGINS_DIR HOSTLIBS - ifneq ($(CFLAGS_KCOV), $(SANCOV_PLUGIN)) GCC_PLUGIN := $(filter-out $(SANCOV_PLUGIN), $(GCC_PLUGIN)) endif -$(HOSTLIBS)-y := $(GCC_PLUGIN) +export HOSTLIBS + +$(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p))) always := $($(HOSTLIBS)-y) $(foreach p,$($(HOSTLIBS)-y:%.so=%),$(eval $(p)-objs := $(p).o)) +subdir-y := $(GCC_PLUGIN_SUBDIR) +subdir- += $(GCC_PLUGIN_SUBDIR) + clean-files += *.so -- cgit v1.2.3