From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
KASAN accesses some slab related struct page fields so we need to convert it
to struct slab. Some places are a bit simplified thanks to kasan_addr_to_slab()
encapsulating the PageSlab flag check through virt_to_slab().
When resolving object address to either a real slab or a large kmalloc, use
struct folio as the intermediate type for testing the slab flag to avoid
unnecessary implicit compound_head().
[ vbabka@xxxxxxx: use struct folio, adjust to differences in previous patches ]
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: <kasan-dev@xxxxxxxxxxxxxxxx>
---
include/linux/kasan.h | 9 +++++----
mm/kasan/common.c | 23 +++++++++++++----------
mm/kasan/generic.c | 8 ++++----
mm/kasan/kasan.h | 1 +
mm/kasan/quarantine.c | 2 +-
mm/kasan/report.c | 13 +++++++++++--
mm/kasan/report_tags.c | 10 +++++-----
mm/slab.c | 2 +-
mm/slub.c | 2 +-
9 files changed, 42 insertions(+), 28 deletions(-)
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index d8783b682669..fb78108d694e 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -9,6 +9,7 @@
struct kmem_cache;
struct page;
+struct slab;
struct vm_struct;
struct task_struct;
@@ -193,11 +194,11 @@ static __always_inline size_t kasan_metadata_size(struct kmem_cache *cache)
return 0;
}
-void __kasan_poison_slab(struct page *page);
-static __always_inline void kasan_poison_slab(struct page *page)
+void __kasan_poison_slab(struct slab *slab);
+static __always_inline void kasan_poison_slab(struct slab *slab)
{
if (kasan_enabled())
- __kasan_poison_slab(page);
+ __kasan_poison_slab(slab);
}
void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object);
@@ -322,7 +323,7 @@ static inline void kasan_cache_create(struct kmem_cache *cache,
slab_flags_t *flags) {}
static inline void kasan_cache_create_kmalloc(struct kmem_cache *cache) {}
static inline size_t kasan_metadata_size(struct kmem_cache *cache) { return 0; }
-static inline void kasan_poison_slab(struct page *page) {}
+static inline void kasan_poison_slab(struct slab *slab) {}
static inline void kasan_unpoison_object_data(struct kmem_cache *cache,
void *object) {}
static inline void kasan_poison_object_data(struct kmem_cache *cache,
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 6a1cd2d38bff..7c06db78a76c 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -247,8 +247,9 @@ struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
}
#endif
-void __kasan_poison_slab(struct page *page)
+void __kasan_poison_slab(struct slab *slab)
{
+ struct page *page = slab_page(slab);
unsigned long i;
for (i = 0; i < compound_nr(page); i++)
@@ -401,9 +402,9 @@ void __kasan_kfree_large(void *ptr, unsigned long ip)
void __kasan_slab_free_mempool(void *ptr, unsigned long ip)
{
- struct page *page;
+ struct folio *folio;
- page = virt_to_head_page(ptr);
+ folio = virt_to_folio(ptr);
/*
* Even though this function is only called for kmem_cache_alloc and
@@ -411,12 +412,14 @@ void __kasan_slab_free_mempool(void *ptr, unsigned long ip)
* !PageSlab() when the size provided to kmalloc is larger than
* KMALLOC_MAX_SIZE, and kmalloc falls back onto page_alloc.
*/
- if (unlikely(!PageSlab(page))) {
+ if (unlikely(!folio_test_slab(folio))) {
if (____kasan_kfree_large(ptr, ip))
return;
- kasan_poison(ptr, page_size(page), KASAN_FREE_PAGE, false);
+ kasan_poison(ptr, folio_size(folio), KASAN_FREE_PAGE, false);
} else {
- ____kasan_slab_free(page->slab_cache, ptr, ip, false, false);
+ struct slab *slab = folio_slab(folio);
+
+ ____kasan_slab_free(slab->slab_cache, ptr, ip, false, false);
}
}
@@ -560,7 +563,7 @@ void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flags)
{
- struct page *page;
+ struct slab *slab;
if (unlikely(object == ZERO_SIZE_PTR))
return (void *)object;
@@ -572,13 +575,13 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag
*/
kasan_unpoison(object, size, false);
- page = virt_to_head_page(object);
+ slab = virt_to_slab(object);
/* Piggy-back on kmalloc() instrumentation to poison the redzone. */
- if (unlikely(!PageSlab(page)))
+ if (unlikely(!slab))
return __kasan_kmalloc_large(object, size, flags);
else
- return ____kasan_kmalloc(page->slab_cache, object, size, flags);
+ return ____kasan_kmalloc(slab->slab_cache, object, size, flags);
}
bool __kasan_check_byte(const void *address, unsigned long ip)
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index 5d0b79416c4e..a25ad4090615 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -330,16 +330,16 @@ DEFINE_ASAN_SET_SHADOW(f8);
static void __kasan_record_aux_stack(void *addr, bool can_alloc)
{
- struct page *page = kasan_addr_to_page(addr);
+ struct slab *slab = kasan_addr_to_slab(addr);
struct kmem_cache *cache;
struct kasan_alloc_meta *alloc_meta;
void *object;
- if (is_kfence_address(addr) || !(page && PageSlab(page)))
+ if (is_kfence_address(addr) || !slab)
return;
- cache = page->slab_cache;
- object = nearest_obj(cache, page_slab(page), addr);
+ cache = slab->slab_cache;
+ object = nearest_obj(cache, slab, addr);
alloc_meta = kasan_get_alloc_meta(cache, object);
if (!alloc_meta)
return;
diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h
index aebd8df86a1f..c17fa8d26ffe 100644
--- a/mm/kasan/kasan.h
+++ b/mm/kasan/kasan.h
@@ -265,6 +265,7 @@ bool kasan_report(unsigned long addr, size_t size,
void kasan_report_invalid_free(void *object, unsigned long ip);
struct page *kasan_addr_to_page(const void *addr);
+struct slab *kasan_addr_to_slab(const void *addr);
depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
void kasan_set_track(struct kasan_track *track, gfp_t flags);
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c
index d8ccff4c1275..587da8995f2d 100644
--- a/mm/kasan/quarantine.c
+++ b/mm/kasan/quarantine.c
@@ -117,7 +117,7 @@ static unsigned long quarantine_batch_size;
static struct kmem_cache *qlink_to_cache(struct qlist_node *qlink)
{
- return virt_to_head_page(qlink)->slab_cache;
+ return virt_to_slab(qlink)->slab_cache;
}
static void *qlink_to_object(struct qlist_node *qlink, struct kmem_cache *cache)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index e00999dc6499..3ad9624dcc56 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -150,6 +150,14 @@ struct page *kasan_addr_to_page(const void *addr)
return NULL;
}
+struct slab *kasan_addr_to_slab(const void *addr)
+{
+ if ((addr >= (void *)PAGE_OFFSET) &&
+ (addr < high_memory))
+ return virt_to_slab(addr);
+ return NULL;
+}
+
static void describe_object_addr(struct kmem_cache *cache, void *object,
const void *addr)
{
@@ -248,8 +256,9 @@ static void print_address_description(void *addr, u8 tag)
pr_err("\n");
if (page && PageSlab(page)) {
- struct kmem_cache *cache = page->slab_cache;
- void *object = nearest_obj(cache, page_slab(page), addr);
+ struct slab *slab = page_slab(page);
+ struct kmem_cache *cache = slab->slab_cache;
+ void *object = nearest_obj(cache, slab, addr);
describe_object(cache, object, addr, tag);
}
diff --git a/mm/kasan/report_tags.c b/mm/kasan/report_tags.c
index 06c21dd77493..1b41de88c53e 100644
--- a/mm/kasan/report_tags.c
+++ b/mm/kasan/report_tags.c
@@ -12,7 +12,7 @@ const char *kasan_get_bug_type(struct kasan_access_info *info)
#ifdef CONFIG_KASAN_TAGS_IDENTIFY
struct kasan_alloc_meta *alloc_meta;
struct kmem_cache *cache;
- struct page *page;
+ struct slab *slab;
const void *addr;
void *object;
u8 tag;
@@ -20,10 +20,10 @@ const char *kasan_get_bug_type(struct kasan_access_info *info)
tag = get_tag(info->access_addr);
addr = kasan_reset_tag(info->access_addr);
- page = kasan_addr_to_page(addr);
- if (page && PageSlab(page)) {
- cache = page->slab_cache;
- object = nearest_obj(cache, page_slab(page), (void *)addr);
+ slab = kasan_addr_to_slab(addr);
+ if (slab) {
+ cache = slab->slab_cache;
+ object = nearest_obj(cache, slab, (void *)addr);
alloc_meta = kasan_get_alloc_meta(cache, object);
if (alloc_meta) {
diff --git a/mm/slab.c b/mm/slab.c
index 785fffd527fe..fed55fa1b7d0 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2605,7 +2605,7 @@ static struct slab *cache_grow_begin(struct kmem_cache *cachep,
* page_address() in the latter returns a non-tagged pointer,
* as it should be for slab pages.
*/
- kasan_poison_slab(slab_page(slab));
+ kasan_poison_slab(slab);
/* Get slab management. */
freelist = alloc_slabmgmt(cachep, slab, offset,
diff --git a/mm/slub.c b/mm/slub.c
index 61aaaa662c5e..58f0d499a293 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1961,7 +1961,7 @@ static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
slab->slab_cache = s;
- kasan_poison_slab(slab_page(slab));
+ kasan_poison_slab(slab);
start = slab_address(slab);
--
2.33.1
