[PATCH mm v4 16/39] kasan: define KASAN_VMALLOC_INVALID for SW_TAGS

andrey.konovalov
2021-12-20T22:00:18Z

In preparation for adding vmalloc support to SW_TAGS KASAN,
provide a KASAN_VMALLOC_INVALID definition for it.

HW_TAGS KASAN won't be using this value, as it falls back onto
page_alloc for poisoning freed vmalloc() memory.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
mm/kasan/kasan.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 952cd6f9ca46..020f3e57a03f 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -71,18 +71,19 @@ static inline bool kasan_sync_fault_possible(void)
#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */
#define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */
#define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */
+#define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */
#else
#define KASAN_FREE_PAGE KASAN_TAG_INVALID
#define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_FREE KASAN_TAG_INVALID
+#define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only for SW_TAGS */
#endif

#ifdef CONFIG_KASAN_GENERIC

#define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */
#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
-#define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */

/*
* Stack redzone shadow values
--
2.25.1