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kasan: give better names to shadow values

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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.

Link: https://lkml.kernel.org/r/bebcaf4eafdb0cabae0401a69c0af956aa87fcaa.1652111464.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Andrey Konovalov 2022-05-12 20:23:08 -07:00 committed by Andrew Morton
parent 83f8e4a8b4
commit 06bc4cf6cd
5 changed files with 21 additions and 21 deletions
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12
mm/kasan/common.c
View file

@ -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.

6
mm/kasan/generic.c
View file

@ -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;
}

14
mm/kasan/kasan.h
View file

@ -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 ABI, do not change. */

2
mm/kasan/quarantine.c
View file

@ -163,7 +163,7 @@ 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_);

8
mm/kasan/report_generic.c
View file

@ -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: