diff options
Diffstat (limited to 'scripts/gcc-plugins')
| -rw-r--r-- | scripts/gcc-plugins/Kconfig | 142 | ||||
| -rw-r--r-- | scripts/gcc-plugins/Makefile | 5 | ||||
| -rw-r--r-- | scripts/gcc-plugins/gcc-common.h | 26 |
3 files changed, 158 insertions, 15 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 diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index 326254653bd0..aa0d0ec6936d 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -14,8 +14,6 @@ else export HOST_EXTRACXXFLAGS endif -export HOSTLIBS - $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h quiet_cmd_create_randomize_layout_seed = GENSEED $@ cmd_create_randomize_layout_seed = \ @@ -29,7 +27,4 @@ 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 diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h index f46750053377..552d5efd7cb7 100644 --- a/scripts/gcc-plugins/gcc-common.h +++ b/scripts/gcc-plugins/gcc-common.h @@ -392,13 +392,6 @@ static inline struct cgraph_node *cgraph_alias_target(struct cgraph_node *n) } #endif -#if BUILDING_GCC_VERSION >= 4007 && BUILDING_GCC_VERSION <= 4009 -#define cgraph_create_edge(caller, callee, call_stmt, count, freq, nest) \ - cgraph_create_edge((caller), (callee), (call_stmt), (count), (freq)) -#define cgraph_create_edge_including_clones(caller, callee, old_call_stmt, call_stmt, count, freq, nest, reason) \ - cgraph_create_edge_including_clones((caller), (callee), (old_call_stmt), (call_stmt), (count), (freq), (reason)) -#endif - #if BUILDING_GCC_VERSION <= 4008 #define ENTRY_BLOCK_PTR_FOR_FN(FN) ENTRY_BLOCK_PTR_FOR_FUNCTION(FN) #define EXIT_BLOCK_PTR_FOR_FN(FN) EXIT_BLOCK_PTR_FOR_FUNCTION(FN) @@ -723,10 +716,23 @@ static inline const char *get_decl_section_name(const_tree decl) #define varpool_get_node(decl) varpool_node::get(decl) #define dump_varpool_node(file, node) (node)->dump(file) -#define cgraph_create_edge(caller, callee, call_stmt, count, freq, nest) \ +#if BUILDING_GCC_VERSION >= 8000 +#define cgraph_create_edge(caller, callee, call_stmt, count, freq) \ + (caller)->create_edge((callee), (call_stmt), (count)) + +#define cgraph_create_edge_including_clones(caller, callee, \ + old_call_stmt, call_stmt, count, freq, reason) \ + (caller)->create_edge_including_clones((callee), \ + (old_call_stmt), (call_stmt), (count), (reason)) +#else +#define cgraph_create_edge(caller, callee, call_stmt, count, freq) \ (caller)->create_edge((callee), (call_stmt), (count), (freq)) -#define cgraph_create_edge_including_clones(caller, callee, old_call_stmt, call_stmt, count, freq, nest, reason) \ - (caller)->create_edge_including_clones((callee), (old_call_stmt), (call_stmt), (count), (freq), (reason)) + +#define cgraph_create_edge_including_clones(caller, callee, \ + old_call_stmt, call_stmt, count, freq, reason) \ + (caller)->create_edge_including_clones((callee), \ + (old_call_stmt), (call_stmt), (count), (freq), (reason)) +#endif typedef struct cgraph_node *cgraph_node_ptr; typedef struct cgraph_edge *cgraph_edge_p; |