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 <re.emese@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
index b4a189c..5e22b60 100644
--- a/scripts/Makefile.gcc-plugins
+++ b/scripts/Makefile.gcc-plugins
@@ -2,10 +2,26 @@
__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 @@
$(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)