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>

diff --git a/arch/Kconfig b/arch/Kconfig
index 8e0d665c8d53d3c57c2c434939f93125472ff610..75dd23acf133b089384db7e9071a37980e98c5ea 100644 (file)
--- 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