From b6cbe3e8bdff6f21f1b58b08a55f479cdcf98282 Mon Sep 17 00:00:00 2001 From: Vasily Gorbik Date: Fri, 17 Nov 2017 17:20:28 +0100 Subject: s390/kasan: avoid user access code instrumentation Kasan instrumentation adds "store" check for variables marked as modified by inline assembly. With user pointers containing addresses from another address space this produces false positives. static inline unsigned long clear_user_xc(void __user *to, ...) { asm volatile( ... : "+a" (to) ... User space access functions are wrapped by manually instrumented functions in kasan common code, which should be sufficient to catch errors. So, we just disable uaccess.o instrumentation altogether. Reviewed-by: Martin Schwidefsky Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky --- arch/s390/lib/Makefile | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/s390/lib') diff --git a/arch/s390/lib/Makefile b/arch/s390/lib/Makefile index 57ab40188d4b..5418d10dc2a8 100644 --- a/arch/s390/lib/Makefile +++ b/arch/s390/lib/Makefile @@ -9,5 +9,9 @@ lib-$(CONFIG_SMP) += spinlock.o lib-$(CONFIG_KPROBES) += probes.o lib-$(CONFIG_UPROBES) += probes.o +# Instrumenting memory accesses to __user data (in different address space) +# produce false positives +KASAN_SANITIZE_uaccess.o := n + chkbss := mem.o include $(srctree)/arch/s390/scripts/Makefile.chkbss -- cgit v1.2.3