[PATCH v3] kconfig.h: Include compiler types to avoid missed struct attributes

[Kees Cook <keescook@chromium.org>]

The header files for some structures could get included in such a way
that struct attributes (specifically __randomize_layout from path.h) would
be parsed as variable names instead of attributes. This could lead to
some instances of a structure being unrandomized, causing nasty GPFs, etc.

This patch makes sure the compiler_types.h header is included in
kconfig.h so that we've always got types and struct attributes defined,
since kconfig.h is included from the compiler command line.

Reported-by: Patrick McLean <chutzpah@gentoo.org>
Root-caused-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Fixes: 3859a271a003 ("randstruct: Mark various structs for randomization")
Signed-off-by: Kees Cook <keescook@chromium.org>
---
Updated to include Tested-by. Linus, this looks ready to go. I'll send
-stable patches that just fix up path.h.
---
 include/linux/kconfig.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h
index fec5076eda91..c5fd4ee776ba 100644
--- a/include/linux/kconfig.h
+++ b/include/linux/kconfig.h
@@ -64,4 +64,7 @@
  */
 #define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
 
+/* Make sure we always have all types and struct attributes defined. */
+#include <linux/compiler_types.h>
+
 #endif /* __LINUX_KCONFIG_H */
-- 
2.7.4


-- 
Kees Cook
Pixel Security