From: Andrey Ryabinin <aryabi...@virtuozzo.com> commit c5caf21ab0cf884ef15b25af234f620e4a233139 upstream.
In the upcoming gcc7 release, the -fsanitize=kernel-address option at first implied new -fsanitize-address-use-after-scope option. This would cause link errors on older kernels because they don't have two new functions required for use-after-scope support. Therefore, gcc7 changed default to -fno-sanitize-address-use-after-scope. Now the kernel has everything required for that feature since commit 828347f8f9a5 ("kasan: support use-after-scope detection"). So, to make it work, we just have to enable use-after-scope in CFLAGS. Link: http://lkml.kernel.org/r/1481207977-28654-1-git-send-email-aryabi...@virtuozzo.com Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com> Acked-by: Dmitry Vyukov <dvyu...@google.com> Cc: Alexander Potapenko <gli...@google.com> Cc: Andrey Konovalov <andreyk...@google.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Andrey Konovalov <andreyk...@google.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- scripts/Makefile.kasan | 2 ++ 1 file changed, 2 insertions(+) --- a/scripts/Makefile.kasan +++ b/scripts/Makefile.kasan @@ -29,6 +29,8 @@ else endif endif +CFLAGS_KASAN += $(call cc-option, -fsanitize-address-use-after-scope) + CFLAGS_KASAN_NOSANITIZE := -fno-builtin endif