lkml.org 
[lkml]   [2018]   [Mar]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 3/7] Disable instrumentation for some code
From
Date
On 18/03/18 12:53, Abbott Liu wrote:
> From: Andrey Ryabinin <a.ryabinin@samsung.com>
>
> Disable instrumentation for arch/arm/boot/compressed/*
> and arch/arm/vdso/* because those code won't linkd with
> kernel image.
>
> Disable kasan check in the function unwind_pop_register
> because it doesn't matter that kasan checks failed when
> unwind_pop_register read stack memory of task.
>
> Reviewed-by: Russell King - ARM Linux <linux@armlinux.org.uk>
> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
> Tested-by: Florian Fainelli <f.fainelli@gmail.com>
> Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
> ---
> arch/arm/boot/compressed/Makefile | 1 +
> arch/arm/kernel/unwind.c | 3 ++-
> arch/arm/vdso/Makefile | 2 ++
> 3 files changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
> index 45a6b9b..966103e 100644
> --- a/arch/arm/boot/compressed/Makefile
> +++ b/arch/arm/boot/compressed/Makefile
> @@ -24,6 +24,7 @@ OBJS += hyp-stub.o
> endif
>
> GCOV_PROFILE := n
> +KASAN_SANITIZE := n
>
> #
> # Architecture dependencies
> diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c
> index 0bee233..2e55c7d 100644
> --- a/arch/arm/kernel/unwind.c
> +++ b/arch/arm/kernel/unwind.c
> @@ -249,7 +249,8 @@ static int unwind_pop_register(struct unwind_ctrl_block *ctrl,
> if (*vsp >= (unsigned long *)ctrl->sp_high)
> return -URC_FAILURE;
>
> - ctrl->vrs[reg] = *(*vsp)++;
> + ctrl->vrs[reg] = READ_ONCE_NOCHECK(*(*vsp));
> + (*vsp)++;
> return URC_OK;
> }
>
> diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
> index bb411821..87abbb7 100644
> --- a/arch/arm/vdso/Makefile
> +++ b/arch/arm/vdso/Makefile
> @@ -30,6 +30,8 @@ CFLAGS_vgettimeofday.o = -O2
> # Disable gcov profiling for VDSO code
> GCOV_PROFILE := n
>
> +KASAN_SANITIZE := n
> +
> # Force dependency
> $(obj)/vdso.o : $(obj)/vdso.so
>
>

You need to extend this at least to arch/arm/kvm/hyp/Makefile, as the
KASAN shadow region won't be mapped in HYP. See commit a6cdf1c08cbfe for
more details (all the arm64 comments in this patch apply to 32bit as well).

Thanks,

M.
--
Jazz is not dead. It just smells funny...

\
 
 \ /
  Last update: 2018-03-19 09:39    [W:0.078 / U:1.292 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site