From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Mon, 29 Oct 2018 10:29:23 +0000 Subject: [PATCH v2 2/3] arm64: lib: use C string functions with KASAN enabled. In-Reply-To: <20180920135631.23833-2-aryabinin@virtuozzo.com> References: <20180914152800.GB6236@arm.com> <20180920135631.23833-1-aryabinin@virtuozzo.com> <20180920135631.23833-2-aryabinin@virtuozzo.com> Message-ID: <20181029102922.GC14127@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Sep 20, 2018 at 04:56:30PM +0300, Andrey Ryabinin wrote: > 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. > > Reported-by: Kyeongdon Kim > Signed-off-by: Andrey Ryabinin > --- > Changes since v1: > - Use WEAK() instead of .weak > > arch/arm64/include/asm/string.h | 14 ++++++++------ > arch/arm64/kernel/arm64ksyms.c | 7 +++++-- > arch/arm64/lib/memchr.S | 2 +- > arch/arm64/lib/memcmp.S | 2 +- > arch/arm64/lib/strchr.S | 2 +- > arch/arm64/lib/strcmp.S | 2 +- > arch/arm64/lib/strlen.S | 2 +- > arch/arm64/lib/strncmp.S | 2 +- > arch/arm64/lib/strnlen.S | 2 +- > arch/arm64/lib/strrchr.S | 2 +- > 10 files changed, 21 insertions(+), 16 deletions(-) Acked-by: Will Deacon Please post these again after the merge window and we'll figure out how to get them queued. Will