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authorMasahiro Yamada <yamada.masahiro@socionext.com>2018-07-05 09:24:12 +0300
committerKees Cook <keescook@chromium.org>2018-07-25 02:11:07 +0300
commit45332b1bdfdc8d63ae4a9d32cbb10e11bc20baab (patch)
treead1a1512e4156cfe292434ce3261c8f11d423459 /scripts/gcc-plugins
parentc17d6179ad5aec2a6ef85f8555454e9cefd4b9fb (diff)
downloadlinux-45332b1bdfdc8d63ae4a9d32cbb10e11bc20baab.tar.xz
gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig
Collect relevant code into the scripts/gcc-plugins directory. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'scripts/gcc-plugins')
-rw-r--r--scripts/gcc-plugins/Kconfig142
1 files changed, 142 insertions, 0 deletions
diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
new file mode 100644
index 000000000000..7430a7c77a4a
--- /dev/null
+++ b/scripts/gcc-plugins/Kconfig
@@ -0,0 +1,142 @@
+preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC))
+
+config PLUGIN_HOSTCC
+ string
+ default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")"
+ help
+ Host compiler used to build GCC plugins. This can be $(HOSTCXX),
+ $(HOSTCC), or a null string if GCC plugin is unsupported.
+
+config HAVE_GCC_PLUGINS
+ bool
+ help
+ An arch should select this symbol if it supports building with
+ GCC plugins.
+
+menuconfig GCC_PLUGINS
+ bool "GCC plugins"
+ depends on HAVE_GCC_PLUGINS
+ depends on PLUGIN_HOSTCC != ""
+ help
+ GCC plugins are loadable modules that provide extra features to the
+ compiler. They are useful for runtime instrumentation and static analysis.
+
+ See Documentation/gcc-plugins.txt for details.
+
+if GCC_PLUGINS
+
+config GCC_PLUGIN_CYC_COMPLEXITY
+ bool "Compute the cyclomatic complexity of a function" if EXPERT
+ depends on !COMPILE_TEST # too noisy
+ 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).
+
+ Enabling this plugin reports the complexity to stderr during the
+ build. It mainly serves as a simple example of how to create a
+ gcc plugin for the kernel.
+
+config GCC_PLUGIN_SANCOV
+ bool
+ 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 <dvyukov@google.com>.
+
+config GCC_PLUGIN_LATENT_ENTROPY
+ bool "Generate some entropy during boot and runtime"
+ help
+ By saying Y here the kernel will instrument some kernel code to
+ extract some entropy from both original and artificially created
+ program state. This will help especially embedded systems where
+ there is little 'natural' source of entropy normally. The cost
+ is some slowdown of the boot process (about 0.5%) and fork and
+ irq processing.
+
+ Note that entropy extracted this way is not cryptographically
+ secure!
+
+ This plugin was ported from grsecurity/PaX. More information at:
+ * https://grsecurity.net/
+ * https://pax.grsecurity.net/
+
+config GCC_PLUGIN_STRUCTLEAK
+ bool "Force initialization of variables containing userspace addresses"
+ # Currently STRUCTLEAK inserts initialization out of live scope of
+ # variables from KASAN point of view. This leads to KASAN false
+ # positive reports. Prohibit this combination for now.
+ depends on !KASAN_EXTRA
+ help
+ This plugin zero-initializes any structures containing a
+ __user attribute. This can prevent some classes of information
+ exposures.
+
+ This plugin was ported from grsecurity/PaX. More information at:
+ * https://grsecurity.net/
+ * https://pax.grsecurity.net/
+
+config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
+ bool "Force initialize all struct type variables passed by reference"
+ depends on GCC_PLUGIN_STRUCTLEAK
+ depends on !COMPILE_TEST
+ help
+ Zero initialize any struct type local variable that may be passed by
+ reference without having been initialized.
+
+config GCC_PLUGIN_STRUCTLEAK_VERBOSE
+ bool "Report forcefully initialized variables"
+ depends on GCC_PLUGIN_STRUCTLEAK
+ depends on !COMPILE_TEST # too noisy
+ help
+ This option will cause a warning to be printed each time the
+ structleak plugin finds a variable it thinks needs to be
+ initialized. Since not all existing initializers are detected
+ by the plugin, this can produce false positive warnings.
+
+config GCC_PLUGIN_RANDSTRUCT
+ bool "Randomize layout of sensitive kernel structures"
+ select MODVERSIONS if MODULES
+ help
+ If you say Y here, the layouts of structures that are entirely
+ function pointers (and have not been manually annotated with
+ __no_randomize_layout), or structures that have been explicitly
+ marked with __randomize_layout, will be randomized at compile-time.
+ This can introduce the requirement of an additional information
+ exposure vulnerability for exploits targeting these structure
+ types.
+
+ Enabling this feature will introduce some performance impact,
+ slightly increase memory usage, and prevent the use of forensic
+ tools like Volatility against the system (unless the kernel
+ source tree isn't cleaned after kernel installation).
+
+ The seed used for compilation is located at
+ scripts/gcc-plgins/randomize_layout_seed.h. It remains after
+ a make clean to allow for external modules to be compiled with
+ the existing seed and will be removed by a make mrproper or
+ make distclean.
+
+ Note that the implementation requires gcc 4.7 or newer.
+
+ This plugin was ported from grsecurity/PaX. More information at:
+ * https://grsecurity.net/
+ * https://pax.grsecurity.net/
+
+config GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
+ bool "Use cacheline-aware structure randomization"
+ depends on GCC_PLUGIN_RANDSTRUCT
+ depends on !COMPILE_TEST # do not reduce test coverage
+ help
+ If you say Y here, the RANDSTRUCT randomization will make a
+ best effort at restricting randomization to cacheline-sized
+ groups of elements. It will further not randomize bitfields
+ in structures. This reduces the performance hit of RANDSTRUCT
+ at the cost of weakened randomization.
+
+endif