KASAN: prohibit KASAN+STRUCTLEAK combination

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.

Link: http://lkml.kernel.org/r/20180419172451.104700-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/Kconfig b/arch/Kconfig
index 8e0d665c8d53..75dd23acf133 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -464,6 +464,10 @@ config GCC_PLUGIN_LATENT_ENTROPY
 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