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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-15 12:06:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-15 12:06:16 -0700
commit7c7b562c6f0a4fb13eee01cb39b111addfb165e6 (patch)
treef18c6969676d314dba55255a839179ae139617d5
parentMerge tag 'printk-for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk (diff)
parentgcc-plugins: Clean up the cgraph_create_edge* macros (diff)
downloadlinux-dev-7c7b562c6f0a4fb13eee01cb39b111addfb165e6.tar.xz
linux-dev-7c7b562c6f0a4fb13eee01cb39b111addfb165e6.zip
Merge tag 'gcc-plugin-cleanup-v4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc plugin cleanups from Kees Cook: - Kconfig and Makefile clean-ups (Masahiro Yamada, Kees Cook) - gcc-common.h definition clean-ups (Alexander Popov) * tag 'gcc-plugin-cleanup-v4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: Clean up the cgraph_create_edge* macros gcc-plugins: Regularize Makefile.gcc-plugins gcc-plugins: split out Kconfig entries to scripts/gcc-plugins/Kconfig gcc-plugins: remove unused GCC_PLUGIN_SUBDIR
-rw-r--r--arch/Kconfig146
-rw-r--r--scripts/Makefile.gcc-plugins37
-rw-r--r--scripts/gcc-plugins/Kconfig142
-rw-r--r--scripts/gcc-plugins/Makefile5
-rw-r--r--scripts/gcc-plugins/gcc-common.h26
5 files changed, 184 insertions, 172 deletions
diff --git a/arch/Kconfig b/arch/Kconfig
index d1f2ed462ac8..8543bc3c21fe 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -408,150 +408,6 @@ config SECCOMP_FILTER
See Documentation/userspace-api/seccomp_filter.rst for details.
-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.
-
-config GCC_PLUGIN_CYC_COMPLEXITY
- bool "Compute the cyclomatic complexity of a function" if EXPERT
- depends on GCC_PLUGINS
- 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
- 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 <dvyukov@google.com>.
-
-config GCC_PLUGIN_LATENT_ENTROPY
- bool "Generate some entropy during boot and runtime"
- depends on GCC_PLUGINS
- 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"
- depends on GCC_PLUGINS
- # 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"
- depends on GCC_PLUGINS
- 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.
-
config HAVE_STACKPROTECTOR
bool
help
@@ -975,3 +831,5 @@ config REFCOUNT_FULL
security flaw exploits.
source "kernel/gcov/Kconfig"
+
+source "scripts/gcc-plugins/Kconfig"
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
index c961b9a65d11..0a482f341576 100644
--- a/scripts/Makefile.gcc-plugins
+++ b/scripts/Makefile.gcc-plugins
@@ -1,33 +1,44 @@
# SPDX-License-Identifier: GPL-2.0
+
gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so
gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += latent_entropy_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += -DLATENT_ENTROPY_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) \
+ += -DLATENT_ENTROPY_PLUGIN
ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
- DISABLE_LATENT_ENTROPY_PLUGIN += -fplugin-arg-latent_entropy_plugin-disable
+ DISABLE_LATENT_ENTROPY_PLUGIN += -fplugin-arg-latent_entropy_plugin-disable
endif
+export DISABLE_LATENT_ENTROPY_PLUGIN
gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV) += sancov_plugin.so
+
gcc-plugin-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) += structleak_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE) += -fplugin-arg-structleak_plugin-verbose
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL) += -fplugin-arg-structleak_plugin-byref-all
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) += -DSTRUCTLEAK_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE) \
+ += -fplugin-arg-structleak_plugin-verbose
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL) \
+ += -fplugin-arg-structleak_plugin-byref-all
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK) \
+ += -DSTRUCTLEAK_PLUGIN
gcc-plugin-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) += randomize_layout_plugin.so
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) += -DRANDSTRUCT_PLUGIN
-gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE) += -fplugin-arg-randomize_layout_plugin-performance-mode
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT) \
+ += -DRANDSTRUCT_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE) \
+ += -fplugin-arg-randomize_layout_plugin-performance-mode
+# All the plugin CFLAGS are collected here in case a build target needs to
+# filter them out of the KBUILD_CFLAGS.
GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y))
-
-export GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR
-export DISABLE_LATENT_ENTROPY_PLUGIN
-
-# sancov_plugin.so can be only in CFLAGS_KCOV because avoid duplication.
+# The sancov_plugin.so is included via CFLAGS_KCOV, so it is removed here.
GCC_PLUGINS_CFLAGS := $(filter-out %/sancov_plugin.so, $(GCC_PLUGINS_CFLAGS))
+export GCC_PLUGINS_CFLAGS
+# Add the flags to the build!
KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS)
+
+# All enabled GCC plugins are collected here for building below.
GCC_PLUGIN := $(gcc-plugin-y)
-GCC_PLUGIN_SUBDIR := $(gcc-plugin-subdir-y)
+export GCC_PLUGIN
# Actually do the build, if requested.
PHONY += gcc-plugins
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;