From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Since commit 7a3b83537188 ("kasan: use separate (un)poison implementation
for integrated init"), when all init, kasan_has_integrated_init(), and
skip_kasan_poison are true, free_pages_prepare() doesn't initialize
the page. This is wrong.
Fix it by remembering whether kasan_poison_pages() performed
initialization, and call kernel_init_free_pages() if it didn't.
Fixes: 7a3b83537188 ("kasan: use separate (un)poison implementation for integrated init")
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
mm/page_alloc.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0673db27dd12..2ada09a58e4b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1360,9 +1360,14 @@ static __always_inline bool free_pages_prepare(struct page *page,
* With hardware tag-based KASAN, memory tags must be set before the
* page becomes unavailable via debug_pagealloc or arch_free_page.
*/
- if (!skip_kasan_poison)
+ if (!skip_kasan_poison) {
kasan_poison_pages(page, order, init);
- if (init && !kasan_has_integrated_init())
+
+ /* Memory is already initialized if KASAN did it internally. */
+ if (kasan_has_integrated_init())
+ init = false;
+ }
+ if (init)
kernel_init_free_pages(page, 1 << order);
/*
--
2.25.1
