From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 1 Feb 2017 12:23:47 -0800 From: Kees Cook Message-ID: <20170201202347.GA75273@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [kernel-hardening] [PATCH] randstruct: Use -Werror=designated-init To: Brad Spengler Cc: Josh Triplett , PaX Team , Emese Revfy , kernel-hardening@lists.openwall.com List-ID: GCC 5.1 and later supports -Werror=designated-init, which can be used with randstruct to locate places where designated initializers are missing. Suggested-by: Josh Triplett Signed-off-by: Kees Cook --- Makefile | 3 +++ include/linux/compiler-gcc.h | 2 ++ scripts/gcc-plugins/randomize_layout_plugin.c | 1 + 3 files changed, 6 insertions(+) diff --git a/Makefile b/Makefile index f21d750fa022..1f94aba409b5 100644 --- a/Makefile +++ b/Makefile @@ -781,6 +781,9 @@ KBUILD_CFLAGS += $(call cc-option,-Werror=date-time) # enforce correct pointer usage KBUILD_CFLAGS += $(call cc-option,-Werror=incompatible-pointer-types) +# Require designated initializers for all marked structures +KBUILD_CFLAGS += $(call cc-option,-Werror=designated-init) + # use the deterministic mode of AR if available KBUILD_ARFLAGS := $(call ar-option,D) diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 3ae2773b0498..fc411495e534 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -197,6 +197,8 @@ #ifdef RANDSTRUCT_PLUGIN #define __randomize_layout __attribute__((randomize_layout)) #define __no_randomize_layout __attribute__((no_randomize_layout)) +#else +#define __randomize_layout __attribute__((designated_init)) #endif #ifdef CONSTIFY_PLUGIN diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 1f62fabc1141..9e314e4d9162 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -377,6 +377,7 @@ static int relayout_struct(tree type) TYPE_FIELDS(variant) = list; TYPE_ATTRIBUTES(variant) = copy_list(TYPE_ATTRIBUTES(variant)); TYPE_ATTRIBUTES(variant) = tree_cons(get_identifier("randomize_performed"), NULL_TREE, TYPE_ATTRIBUTES(variant)); + TYPE_ATTRIBUTES(variant) = tree_cons(get_identifier("designated_init"), NULL_TREE, TYPE_ATTRIBUTES(variant)); if (has_flexarray) TYPE_ATTRIBUTES(type) = tree_cons(get_identifier("has_flexarray"), NULL_TREE, TYPE_ATTRIBUTES(type)); } -- 2.7.4 -- Kees Cook Pixel Security