Commit bbe71173 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Vlastimil Babka
Browse files

kasan: Remove references to folio in __kasan_mempool_poison_object() 



In preparation for splitting struct slab from struct page and struct
folio, remove mentions of struct folio from this function.  There is a
mild improvement for large kmalloc objects as we will avoid calling
compound_head() for them.  We can discard the comment as using
PageLargeKmalloc() rather than !folio_test_slab() makes it obvious.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: kasan-dev <kasan-dev@googlegroups.com>
Link: https://patch.msgid.link/20251113000932.1589073-16-willy@infradead.org


Acked-by: default avatarHarry Yoo <harry.yoo@oracle.com>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
parent b8557d10

mm/kasan/common.c

+4 −8
Original line number Diff line number Diff line
@@ -520,24 +520,20 @@ void __kasan_mempool_unpoison_pages(struct page *page, unsigned int order, 


bool __kasan_mempool_poison_object(void *ptr, unsigned long ip)

{

	struct folio *folio = virt_to_folio(ptr);

	struct page *page = virt_to_page(ptr);

	struct slab *slab;



	/*

	 * This function can be called for large kmalloc allocation that get

	 * their memory from page_alloc. Thus, the folio might not be a slab.

	 */

	if (unlikely(!folio_test_slab(folio))) {

	if (unlikely(PageLargeKmalloc(page))) {

		if (check_page_allocation(ptr, ip))

			return false;

		kasan_poison(ptr, folio_size(folio), KASAN_PAGE_FREE, false);

		kasan_poison(ptr, page_size(page), KASAN_PAGE_FREE, false);

		return true;

	}



	if (is_kfence_address(ptr))

		return true;



	slab = folio_slab(folio);

	slab = page_slab(page);



	if (check_slab_allocation(slab->slab_cache, ptr, ip))

		return false;