mm: fix wrong kasan report [1/1]

PD#SWPL-13281

Problem:
There are 2 types of wrong kasan report after merge change of
save wasted slab.
1, slab-out-of-bounds, which is caused by krealloc set shadow
   memory out-of-range, since tail of page was freed.
2, use-after-free, which is caused by kasan_free_pages called
   after a page freed. Because this function already called in
   free_page, so it marked shadow memory twice.

Solution:
1, make shadow do not out of range if a tail page was freed and
   been realloc again.
2, remove call of kasan_free_pages.

Verify:
X301

Signed-off-by: Tao Zeng <tao.zeng@amlogic.com>
[sw0312.kim: fully apply amlogic vendor commit becb83999e19 missed from merge]
Ref: https://github.com/hardkernel/linux/commit/becb83999e19d2055458f08a2b7a44bd1170853e
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Change-Id: I71daa41038e156a9bacf26e27fc51792d558f819

diff --git a/mm/slub.c b/mm/slub.c
index d1f5fd0..80f291c 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3808,7 +3808,6 @@ static void aml_slub_free_large(struct page *page, const void *obj)
                        __func__, page_address(page), nr_pages, obj);
                for (i = 0; i < nr_pages; i++)  {
                        __free_pages(page, 0);
-                       kasan_free_pages(page, 0);
                        page++;
                }
        }