diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2023-12-20 01:28:48 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-29 22:58:37 +0300 |
| commit | 2e7c954c11af96aa1e0566a706f22152ef91d759 (patch) | |
| tree | a9a8a0bb18ed84c80745650d2e99ca47edde7b4f /mm/kasan | |
| parent | 1bb843048d00050678c392dab87a15c8b756df6f (diff) | |
| download | linux-2e7c954c11af96aa1e0566a706f22152ef91d759.tar.xz | |
kasan: add return value for kasan_mempool_poison_object
Add a return value for kasan_mempool_poison_object that lets the caller
know whether the allocation is affected by a double-free or an
invalid-free bug. The caller can use this return value to stop operating
on the object.
Also introduce a check_page_allocation helper function to improve the code
readability.
Link: https://lkml.kernel.org/r/618af65273875fb9f56954285443279b15f1fcd9.1703024586.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Lobakin <alobakin@pm.me>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/kasan')
| -rw-r--r-- | mm/kasan/common.c | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c index fc7f711607e1..2b4869de4985 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -254,7 +254,7 @@ bool __kasan_slab_free(struct kmem_cache *cache, void *object, return ____kasan_slab_free(cache, object, ip, true, init); } -static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip) +static inline bool check_page_allocation(void *ptr, unsigned long ip) { if (!kasan_arch_is_ready()) return false; @@ -269,17 +269,14 @@ static inline bool ____kasan_kfree_large(void *ptr, unsigned long ip) return true; } - /* - * The object will be poisoned by kasan_poison_pages() or - * kasan_mempool_poison_object(). - */ - return false; } void __kasan_kfree_large(void *ptr, unsigned long ip) { - ____kasan_kfree_large(ptr, ip); + check_page_allocation(ptr, ip); + + /* The object will be poisoned by kasan_poison_pages(). */ } void * __must_check __kasan_slab_alloc(struct kmem_cache *cache, @@ -429,7 +426,7 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag return ____kasan_kmalloc(slab->slab_cache, object, size, flags); } -void __kasan_mempool_poison_object(void *ptr, unsigned long ip) +bool __kasan_mempool_poison_object(void *ptr, unsigned long ip) { struct folio *folio; @@ -442,13 +439,15 @@ void __kasan_mempool_poison_object(void *ptr, unsigned long ip) * KMALLOC_MAX_SIZE, and kmalloc falls back onto page_alloc. */ if (unlikely(!folio_test_slab(folio))) { - if (____kasan_kfree_large(ptr, ip)) - return; + if (check_page_allocation(ptr, ip)) + return false; kasan_poison(ptr, folio_size(folio), KASAN_PAGE_FREE, false); + return true; } else { struct slab *slab = folio_slab(folio); - ____kasan_slab_free(slab->slab_cache, ptr, ip, false, false); + return !____kasan_slab_free(slab->slab_cache, ptr, ip, + false, false); } } |