[PATCH 3/7] Disable instrumentation for some code
From: Marc Zyngier <hidden>
Date: 2018-03-19 08:38:04
Also in:
kvmarm, linux-mm, lkml
On 18/03/18 12:53, Abbott Liu wrote:
quoted hunk ↗ jump to hunk
From: Andrey Ryabinin <redacted> 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 <redacted> --- 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 dependenciesdiff --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...