Re: [PATCH v6 16/18] khwasan, mm, arm64: tag non slab memory allocated via pagealloc

[Andrey Ryabinin]

On 08/29/2018 02:35 PM, Andrey Konovalov wrote:

>  void kasan_poison_slab(struct page *page)
>  {
> +	unsigned long i;
> +
> +	if (IS_ENABLED(CONFIG_SLAB))
> +		page->s_mem = reset_tag(page->s_mem);

Why reinitialize here, instead of single initialization in alloc_slabmgmt()?


> +	for (i = 0; i < (1 << compound_order(page)); i++)
> +		page_kasan_tag_reset(page + i);
>  	kasan_poison_shadow(page_address(page),
>  			PAGE_SIZE << compound_order(page),
>  			KASAN_KMALLOC_REDZONE);