arm64: lib: use C string functions with KASAN enabled
authorAndrey Ryabinin <aryabinin@virtuozzo.com>
Fri, 26 Oct 2018 22:02:30 +0000 (15:02 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 26 Oct 2018 23:25:18 +0000 (16:25 -0700)
commit19a2ca0fb560fd7be7b5293c6b652c6d6078dcde
treec4ed897c25ef86a5b04565027e6f7e65ff3d7f45
parent74f213ea25b99fddcf34cbe07dabdb01136bcd86
arm64: lib: use C string functions with KASAN enabled

ARM64 has asm implementation of memchr(), memcmp(), str[r]chr(),
str[n]cmp(), str[n]len().  KASAN don't see memory accesses in asm code,
thus it can potentially miss many bugs.

Ifdef out __HAVE_ARCH_* defines of these functions when KASAN is enabled,
so the generic implementations from lib/string.c will be used.

We can't just remove the asm functions because efistub uses them.  And we
can't have two non-weak functions either, so declare the asm functions as
weak.

Link: http://lkml.kernel.org/r/20180920135631.23833-2-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: Kyeongdon Kim <kyeongdon.kim@lge.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/arm64/include/asm/string.h
arch/arm64/kernel/arm64ksyms.c
arch/arm64/lib/memchr.S
arch/arm64/lib/memcmp.S
arch/arm64/lib/strchr.S
arch/arm64/lib/strcmp.S
arch/arm64/lib/strlen.S
arch/arm64/lib/strncmp.S
arch/arm64/lib/strnlen.S
arch/arm64/lib/strrchr.S