Re: [PATCH v10 12/22] kasan, arm64: fix up fault handling logic

From: Catalin Marinas
Date: Wed Nov 07 2018 - 13:26:38 EST


On Tue, Nov 06, 2018 at 06:30:27PM +0100, Andrey Konovalov wrote:
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index 7d9571f4ae3d..d9a84d6f3343 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -32,6 +32,7 @@
> #include <linux/perf_event.h>
> #include <linux/preempt.h>
> #include <linux/hugetlb.h>
> +#include <linux/kasan.h>
>
> #include <asm/bug.h>
> #include <asm/cmpxchg.h>
> @@ -141,6 +142,8 @@ void show_pte(unsigned long addr)
> pgd_t *pgdp;
> pgd_t pgd;
>
> + addr = (unsigned long)kasan_reset_tag((void *)addr);
> +
> if (addr < TASK_SIZE) {
> /* TTBR0 */
> mm = current->active_mm;

I think we should clear the tag earlier on in the fault handling code,
before reaching show_pte().

--
Catalin