[PATCH 3/3] kasan: give better names to shadow values

From: andrey . konovalov
Date: Thu Apr 28 2022 - 12:22:09 EST


From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

Rename KASAN_KMALLOC_* shadow values to KASAN_SLAB_*, as they are used
for all slab allocations, not only for kmalloc.

Also rename KASAN_FREE_PAGE to KASAN_PAGE_FREE to be consistent with
KASAN_PAGE_REDZONE and KASAN_SLAB_FREE.

Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
mm/kasan/common.c | 12 ++++++------
mm/kasan/generic.c | 6 +++---
mm/kasan/kasan.h | 14 +++++++-------
mm/kasan/quarantine.c | 2 +-
mm/kasan/report_generic.c | 8 ++++----
5 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index d9079ec11f31..c40c0e7b3b5f 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -117,7 +117,7 @@ void __kasan_poison_pages(struct page *page, unsigned int order, bool init)
{
if (likely(!PageHighMem(page)))
kasan_poison(page_address(page), PAGE_SIZE << order,
- KASAN_FREE_PAGE, init);
+ KASAN_PAGE_FREE, init);
}

/*
@@ -254,7 +254,7 @@ void __kasan_poison_slab(struct slab *slab)
for (i = 0; i < compound_nr(page); i++)
page_kasan_tag_reset(page + i);
kasan_poison(page_address(page), page_size(page),
- KASAN_KMALLOC_REDZONE, false);
+ KASAN_SLAB_REDZONE, false);
}

void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
@@ -265,7 +265,7 @@ void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object)
void __kasan_poison_object_data(struct kmem_cache *cache, void *object)
{
kasan_poison(object, round_up(cache->object_size, KASAN_GRANULE_SIZE),
- KASAN_KMALLOC_REDZONE, false);
+ KASAN_SLAB_REDZONE, false);
}

/*
@@ -357,7 +357,7 @@ static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
}

kasan_poison(object, round_up(cache->object_size, KASAN_GRANULE_SIZE),
- KASAN_KMALLOC_FREE, init);
+ KASAN_SLAB_FREE, init);

if ((IS_ENABLED(CONFIG_KASAN_GENERIC) && !quarantine))
return false;
@@ -414,7 +414,7 @@ void __kasan_slab_free_mempool(void *ptr, unsigned long ip)
if (unlikely(!folio_test_slab(folio))) {
if (____kasan_kfree_large(ptr, ip))
return;
- kasan_poison(ptr, folio_size(folio), KASAN_FREE_PAGE, false);
+ kasan_poison(ptr, folio_size(folio), KASAN_PAGE_FREE, false);
} else {
struct slab *slab = folio_slab(folio);

@@ -505,7 +505,7 @@ static inline void *____kasan_kmalloc(struct kmem_cache *cache,
redzone_end = round_up((unsigned long)(object + cache->object_size),
KASAN_GRANULE_SIZE);
kasan_poison((void *)redzone_start, redzone_end - redzone_start,
- KASAN_KMALLOC_REDZONE, false);
+ KASAN_SLAB_REDZONE, false);

/*
* Save alloc info (if possible) for kmalloc() allocations.
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index a25ad4090615..437fcc7e77cf 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -369,14 +369,14 @@ void kasan_set_free_info(struct kmem_cache *cache,

kasan_set_track(&free_meta->free_track, GFP_NOWAIT);
/* The object was freed and has free track set. */
- *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREETRACK;
+ *(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREETRACK;
}

struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
void *object, u8 tag)
{
- if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_KMALLOC_FREETRACK)
+ if (*(u8 *)kasan_mem_to_shadow(object) != KASAN_SLAB_FREETRACK)
return NULL;
- /* Free meta must be present with KASAN_KMALLOC_FREETRACK. */
+ /* Free meta must be present with KASAN_SLAB_FREETRACK. */
return &kasan_get_free_meta(cache, object)->free_track;
}
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index 06fdea41ca4a..41681d3c551d 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -74,22 +74,22 @@ static inline bool kasan_sync_fault_possible(void)
#define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)

#ifdef CONFIG_KASAN_GENERIC
-#define KASAN_FREE_PAGE 0xFF /* freed page */
+#define KASAN_PAGE_FREE 0xFF /* freed page */
#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocation */
-#define KASAN_KMALLOC_REDZONE 0xFC /* redzone for slab object */
-#define KASAN_KMALLOC_FREE 0xFB /* freed slab object */
+#define KASAN_SLAB_REDZONE 0xFC /* redzone for slab object */
+#define KASAN_SLAB_FREE 0xFB /* freed slab object */
#define KASAN_VMALLOC_INVALID 0xF8 /* inaccessible space in vmap area */
#else
-#define KASAN_FREE_PAGE KASAN_TAG_INVALID
+#define KASAN_PAGE_FREE 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_SLAB_REDZONE KASAN_TAG_INVALID
+#define KASAN_SLAB_FREE KASAN_TAG_INVALID
#define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only used for SW_TAGS */
#endif

#ifdef CONFIG_KASAN_GENERIC

-#define KASAN_KMALLOC_FREETRACK 0xFA /* freed slab object with free track */
+#define KASAN_SLAB_FREETRACK 0xFA /* freed slab object with free track */
#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */

/* Stack redzone shadow values. Compiler's ABI, do not change. */
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index 0a9def8ce5e8..fac4befb9ef2 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -152,7 +152,7 @@ static void qlink_free(struct qlist_node *qlink, struct kmem_cache *cache)
* As the object now gets freed from the quarantine, assume that its
* free track is no longer valid.
*/
- *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREE;
+ *(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREE;

___cache_free(cache, object, _THIS_IP_);

diff --git a/mm/kasan/report_generic.c b/mm/kasan/report_generic.c
index efc5e79a103f..6689fb9a919b 100644
--- a/mm/kasan/report_generic.c
+++ b/mm/kasan/report_generic.c
@@ -66,7 +66,7 @@ static const char *get_shadow_bug_type(struct kasan_report_info *info)
bug_type = "out-of-bounds";
break;
case KASAN_PAGE_REDZONE:
- case KASAN_KMALLOC_REDZONE:
+ case KASAN_SLAB_REDZONE:
bug_type = "slab-out-of-bounds";
break;
case KASAN_GLOBAL_REDZONE:
@@ -78,9 +78,9 @@ static const char *get_shadow_bug_type(struct kasan_report_info *info)
case KASAN_STACK_PARTIAL:
bug_type = "stack-out-of-bounds";
break;
- case KASAN_FREE_PAGE:
- case KASAN_KMALLOC_FREE:
- case KASAN_KMALLOC_FREETRACK:
+ case KASAN_PAGE_FREE:
+ case KASAN_SLAB_FREE:
+ case KASAN_SLAB_FREETRACK:
bug_type = "use-after-free";
break;
case KASAN_ALLOCA_LEFT:
--
2.25.1