[merged] mm-kasan-fix-to-call-kasan_free_pages-after-poisoning-page.patch removed from -mm tree

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The patch titled
     Subject: mm, kasan: fix to call kasan_free_pages() after poisoning page
has been removed from the -mm tree.  Its filename was
     mm-kasan-fix-to-call-kasan_free_pages-after-poisoning-page.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: "seokhoon.yoon" <iamyooon@xxxxxxxxx>
Subject: mm, kasan: fix to call kasan_free_pages() after poisoning page

When CONFIG_PAGE_POISONING and CONFIG_KASAN is enabled,
free_pages_prepare()'s codeflow is below.

1)kmemcheck_free_shadow()
2)kasan_free_pages()
- set shadow byte of page is freed
3)kernel_poison_pages()
3.1) check access to page is valid or not using kasan
---> error occur, kasan think it is invalid access
3.2) poison page
4)kernel_map_pages()

So kasan_free_pages() should be called after poisoning the page.

Link: http://lkml.kernel.org/r/1463220405-7455-1-git-send-email-iamyooon@xxxxxxxxx
Signed-off-by: seokhoon.yoon <iamyooon@xxxxxxxxx>
Cc: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/page_alloc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN mm/page_alloc.c~mm-kasan-fix-to-call-kasan_free_pages-after-poisoning-page mm/page_alloc.c
--- a/mm/page_alloc.c~mm-kasan-fix-to-call-kasan_free_pages-after-poisoning-page
+++ a/mm/page_alloc.c
@@ -993,7 +993,6 @@ static __always_inline bool free_pages_p
 
 	trace_mm_page_free(page, order);
 	kmemcheck_free_shadow(page, order);
-	kasan_free_pages(page, order);
 
 	/*
 	 * Check tail pages before head page information is cleared to
@@ -1035,6 +1034,7 @@ static __always_inline bool free_pages_p
 	arch_free_page(page, order);
 	kernel_poison_pages(page, 1 << order, 0);
 	kernel_map_pages(page, 1 << order, 0);
+	kasan_free_pages(page, order);
 
 	return true;
 }
_

Patches currently in -mm which might be from iamyooon@xxxxxxxxx are


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