[PATCH mm v3 19/34] kasan: pass tagged pointers to kasan_save_alloc/free_info

From: andrey . konovalov
Date: Mon Sep 05 2022 - 17:10:01 EST


From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

Pass tagged pointers to kasan_save_alloc/free_info().

This is a preparatory patch to simplify other changes in the series.

Reviewed-by: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

---

Changes v1->v2:
- Drop unused variable tag from ____kasan_slab_free().
---
mm/kasan/common.c | 6 ++----
mm/kasan/generic.c | 3 +--
mm/kasan/kasan.h | 2 +-
mm/kasan/tags.c | 3 +--
4 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 8efa63190951..f8e16a242197 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -193,13 +193,11 @@ void * __must_check __kasan_init_slab_obj(struct kmem_cache *cache,
static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
unsigned long ip, bool quarantine, bool init)
{
- u8 tag;
void *tagged_object;

if (!kasan_arch_is_ready())
return false;

- tag = get_tag(object);
tagged_object = object;
object = kasan_reset_tag(object);

@@ -228,7 +226,7 @@ static inline bool ____kasan_slab_free(struct kmem_cache *cache, void *object,
return false;

if (kasan_stack_collection_enabled())
- kasan_save_free_info(cache, object, tag);
+ kasan_save_free_info(cache, tagged_object);

return kasan_quarantine_put(cache, object);
}
@@ -317,7 +315,7 @@ void * __must_check __kasan_slab_alloc(struct kmem_cache *cache,

/* Save alloc info (if possible) for non-kmalloc() allocations. */
if (kasan_stack_collection_enabled() && !cache->kasan_info.is_kmalloc)
- kasan_save_alloc_info(cache, (void *)object, flags);
+ kasan_save_alloc_info(cache, tagged_object, flags);

return tagged_object;
}
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index f6bef347de87..aff39af3c532 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -500,8 +500,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
kasan_set_track(&alloc_meta->alloc_track, flags);
}

-void kasan_save_free_info(struct kmem_cache *cache,
- void *object, u8 tag)
+void kasan_save_free_info(struct kmem_cache *cache, void *object)
{
struct kasan_free_meta *free_meta;

diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index cae60e4d8842..cca49ab029f1 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -309,7 +309,7 @@ static inline void kasan_init_object_meta(struct kmem_cache *cache, const void *
depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
void kasan_set_track(struct kasan_track *track, gfp_t flags);
void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags);
-void kasan_save_free_info(struct kmem_cache *cache, void *object, u8 tag);
+void kasan_save_free_info(struct kmem_cache *cache, void *object);
struct kasan_track *kasan_get_alloc_track(struct kmem_cache *cache,
void *object);
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c
index 4f24669085e9..fd11d10a4ffc 100644
--- a/mm/kasan/tags.c
+++ b/mm/kasan/tags.c
@@ -21,8 +21,7 @@ void kasan_save_alloc_info(struct kmem_cache *cache, void *object, gfp_t flags)
{
}

-void kasan_save_free_info(struct kmem_cache *cache,
- void *object, u8 tag)
+void kasan_save_free_info(struct kmem_cache *cache, void *object)
{
}

--
2.25.1