From 70c248aca9e7efa85a6664d5ab56c17c326c958f Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Fri, 10 Jun 2022 16:21:39 +0100 Subject: mm: kasan: Skip unpoisoning of user pages Commit c275c5c6d50a ("kasan: disable freed user page poisoning with HW tags") added __GFP_SKIP_KASAN_POISON to GFP_HIGHUSER_MOVABLE. A similar argument can be made about unpoisoning, so also add __GFP_SKIP_KASAN_UNPOISON to user pages. To ensure the user page is still accessible via page_address() without a kasan fault, reset the page->flags tag. With the above changes, there is no need for the arm64 tag_clear_highpage() to reset the page->flags tag. Signed-off-by: Catalin Marinas Cc: Andrey Ryabinin Cc: Andrey Konovalov Cc: Peter Collingbourne Cc: Vincenzo Frascino Reviewed-by: Vincenzo Frascino Reviewed-by: Andrey Konovalov Link: https://lore.kernel.org/r/20220610152141.2148929-3-catalin.marinas@arm.com Signed-off-by: Will Deacon --- arch/arm64/mm/fault.c | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/arm64/mm/fault.c') diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index c5e11768e5c1..cdf3ffa0c223 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -927,6 +927,5 @@ struct page *alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma, void tag_clear_highpage(struct page *page) { mte_zero_clear_page_tags(page_address(page)); - page_kasan_tag_reset(page); set_bit(PG_mte_tagged, &page->flags); } -- cgit v1.2.3