Merge tag 'gcc-plugins-v4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull GCC plugin updates from Kees Cook:
 "The big part is the randstruct plugin infrastructure.

  This is the first of two expected pull requests for randstruct since
  there are dependencies in other trees that would be easier to merge
  once those have landed. Notably, the IPC allocation refactoring in
  -mm, and many trivial merge conflicts across several trees when
  applying the __randomize_layout annotation.

  As a result, it seemed like I should send this now since it is
  relatively self-contained, and once the rest of the trees have landed,
  send the annotation patches. I'm expecting the final phase of
  randstruct (automatic struct selection) will land for v4.14, but if
  its other tree dependencies actually make it for v4.13, I can send
  that merge request too.

  Summary:

  - typo fix in Kconfig (Jean Delvare)

  - randstruct infrastructure"

* tag 'gcc-plugins-v4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  ARM: Prepare for randomized task_struct
  randstruct: Whitelist NIU struct page overloading
  randstruct: Whitelist big_key path struct overloading
  randstruct: Whitelist UNIXCB cast
  randstruct: Whitelist struct security_hook_heads cast
  gcc-plugins: Add the randstruct plugin
  Fix English in description of GCC_PLUGIN_STRUCTLEAK
  compiler: Add __designated_init annotation
  gcc-plugins: Detail c-common.h location for GCC 4.6

scripts/Makefile.gcc-plugins

@@ -29,6 +29,10 @@ ifdef CONFIG_GCC_PLUGINS
   gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE)	+= -fplugin-arg-structleak_plugin-verbose
   gcc-plugin-cflags-$(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_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y))
 
   export PLUGINCC GCC_PLUGINS_CFLAGS GCC_PLUGIN GCC_PLUGIN_SUBDIR

scripts/gcc-plugins/.gitignore

@@ -0,0 +1 @@
+randomize_layout_seed.h

scripts/gcc-plugins/Makefile

@@ -18,6 +18,14 @@ 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 = \
+  $(CONFIG_SHELL) $(srctree)/$(src)/gen-random-seed.sh $@ $(objtree)/include/generated/randomize_layout_hash.h
+$(objtree)/$(obj)/randomize_layout_seed.h: FORCE
+	$(call if_changed,create_randomize_layout_seed)
+targets = randomize_layout_seed.h randomize_layout_hash.h
+
 $(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p)))
 always := $($(HOSTLIBS)-y)
 

scripts/gcc-plugins/gcc-common.h

@@ -63,6 +63,13 @@
 #endif
 
 #if BUILDING_GCC_VERSION >= 4006
+/*
+ * The c-family headers were moved into a subdirectory in GCC version
+ * 4.7, but most plugin-building users of GCC 4.6 are using the Debian
+ * or Ubuntu package, which has an out-of-tree patch to move this to the
+ * same location as found in 4.7 and later:
+ * https://sources.debian.net/src/gcc-4.6/4.6.3-14/debian/patches/pr45078.diff/
+ */
 #include "c-family/c-common.h"
 #else
 #include "c-common.h"
@@ -946,4 +953,9 @@ static inline void debug_gimple_stmt(const_gimple s)
 	get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep)
 #endif
 
+#if BUILDING_GCC_VERSION < 7000
+#define SET_DECL_ALIGN(decl, align)	DECL_ALIGN(decl) = (align)
+#define SET_DECL_MODE(decl, mode)	DECL_MODE(decl) = (mode)
+#endif
+
 #endif

scripts/gcc-plugins/gen-random-seed.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+if [ ! -f "$1" ]; then
+	SEED=`od -A n -t x8 -N 32 /dev/urandom | tr -d ' \n'`
+	echo "const char *randstruct_seed = \"$SEED\";" > "$1"
+	HASH=`echo -n "$SEED" | sha256sum | cut -d" " -f1 | tr -d ' \n'`
+	echo "#define RANDSTRUCT_HASHED_SEED \"$HASH\"" > "$2"
+fi