diff options
| author | Dmitry Vyukov <dvyukov@google.com> | 2018-02-06 15:36:23 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-06 18:32:42 -0800 |
| commit | 47adccce3e8a31d315f47183ab1185862b2fc5d4 (patch) | |
| tree | aaf982ef67484b702b42440b459cfd648e58dc4e /include | |
| parent | d321599cf6b861beefe92327476b617435c7fc4a (diff) | |
kasan: detect invalid frees for large objects
Patch series "kasan: detect invalid frees".
KASAN detects double-frees, but does not detect invalid-frees (when a
pointer into a middle of heap object is passed to free). We recently had
a very unpleasant case in crypto code which freed an inner object inside
of a heap allocation. This left unnoticed during free, but totally
corrupted heap and later lead to a bunch of random crashes all over kernel
code.
Detect invalid frees.
This patch (of 5):
Detect frees of pointers into middle of large heap objects.
I dropped const from kasan_kfree_large() because it starts propagating
through a bunch of functions in kasan_report.c, slab/slub nearest_obj(),
all of their local variables, fixup_red_left(), etc.
Link: http://lkml.kernel.org/r/1b45b4fe1d20fc0de1329aab674c1dd973fee723.1514378558.git.dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>a
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/kasan.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/kasan.h b/include/linux/kasan.h index e3eb834c9a35..fc9e642533f8 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -56,7 +56,7 @@ void kasan_poison_object_data(struct kmem_cache *cache, void *object); void kasan_init_slab_obj(struct kmem_cache *cache, const void *object); void kasan_kmalloc_large(const void *ptr, size_t size, gfp_t flags); -void kasan_kfree_large(const void *ptr); +void kasan_kfree_large(void *ptr); void kasan_poison_kfree(void *ptr); void kasan_kmalloc(struct kmem_cache *s, const void *object, size_t size, gfp_t flags); @@ -108,7 +108,7 @@ static inline void kasan_init_slab_obj(struct kmem_cache *cache, const void *object) {} static inline void kasan_kmalloc_large(void *ptr, size_t size, gfp_t flags) {} -static inline void kasan_kfree_large(const void *ptr) {} +static inline void kasan_kfree_large(void *ptr) {} static inline void kasan_poison_kfree(void *ptr) {} static inline void kasan_kmalloc(struct kmem_cache *s, const void *object, size_t size, gfp_t flags) {} |