__builtin_return_address(1) is unreliable without frame pointers. With defconfig on kmalloc_pagealloc_invalid_free test I am getting:
BUG: KASAN: double-free or invalid-free in (null) Pass caller PC from callers explicitly. Signed-off-by: Dmitry Vyukov <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] --- include/linux/kasan.h | 9 +++++---- mm/kasan/kasan.c | 8 ++++---- mm/kasan/kasan.h | 2 +- mm/kasan/report.c | 4 ++-- mm/slab.c | 6 +++--- mm/slub.c | 8 ++++---- 6 files changed, 19 insertions(+), 18 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index fc9e642533f8..f0d13c30acc6 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -56,14 +56,14 @@ 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(void *ptr); +void kasan_kfree_large(void *ptr, unsigned long ip); void kasan_poison_kfree(void *ptr); void kasan_kmalloc(struct kmem_cache *s, const void *object, size_t size, gfp_t flags); void kasan_krealloc(const void *object, size_t new_size, gfp_t flags); void kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags); -bool kasan_slab_free(struct kmem_cache *s, void *object); +bool kasan_slab_free(struct kmem_cache *s, void *object, unsigned long ip); struct kasan_cache { int alloc_meta_offset; @@ -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(void *ptr) {} +static inline void kasan_kfree_large(void *ptr, unsigned long ip) {} 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) {} @@ -117,7 +117,8 @@ static inline void kasan_krealloc(const void *object, size_t new_size, static inline void kasan_slab_alloc(struct kmem_cache *s, void *object, gfp_t flags) {} -static inline bool kasan_slab_free(struct kmem_cache *s, void *object) +static inline bool kasan_slab_free(struct kmem_cache *s, void *object, + unsigned long ip) { return false; } diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index ecb64fda79e6..32f555ded938 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -501,7 +501,7 @@ static void kasan_poison_slab_free(struct kmem_cache *cache, void *object) kasan_poison_shadow(object, rounded_up_size, KASAN_KMALLOC_FREE); } -bool kasan_slab_free(struct kmem_cache *cache, void *object) +bool kasan_slab_free(struct kmem_cache *cache, void *object, unsigned long ip) { s8 shadow_byte; @@ -511,7 +511,7 @@ bool kasan_slab_free(struct kmem_cache *cache, void *object) shadow_byte = READ_ONCE(*(s8 *)kasan_mem_to_shadow(object)); if (shadow_byte < 0 || shadow_byte >= KASAN_SHADOW_SCALE_SIZE) { - kasan_report_invalid_free(object, __builtin_return_address(1)); + kasan_report_invalid_free(object, ip); return true; } @@ -601,10 +601,10 @@ void kasan_poison_kfree(void *ptr) kasan_poison_slab_free(page->slab_cache, ptr); } -void kasan_kfree_large(void *ptr) +void kasan_kfree_large(void *ptr, unsigned long ip) { if (ptr != page_address(virt_to_head_page(ptr))) - kasan_report_invalid_free(ptr, __builtin_return_address(1)); + kasan_report_invalid_free(ptr, ip); /* The object will be poisoned by page_alloc. */ } diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h index 57f517d1dfce..2792de927fcd 100644 --- a/mm/kasan/kasan.h +++ b/mm/kasan/kasan.h @@ -107,7 +107,7 @@ static inline const void *kasan_shadow_to_mem(const void *shadow_addr) void kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip); -void kasan_report_invalid_free(void *object, void *ip); +void kasan_report_invalid_free(void *object, unsigned long ip); #if defined(CONFIG_SLAB) || defined(CONFIG_SLUB) void quarantine_put(struct kasan_free_meta *info, struct kmem_cache *cache); diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 55916ad21722..75206991ece0 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -326,12 +326,12 @@ static void print_shadow_for_address(const void *addr) } } -void kasan_report_invalid_free(void *object, void *ip) +void kasan_report_invalid_free(void *object, unsigned long ip) { unsigned long flags; kasan_start_report(&flags); - pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", ip); + pr_err("BUG: KASAN: double-free or invalid-free in %pS\n", (void *)ip); pr_err("\n"); print_address_description(object); pr_err("\n"); diff --git a/mm/slab.c b/mm/slab.c index 6bc4e609e24b..d074fd0790f4 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3478,11 +3478,11 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) * Release an obj back to its cache. If the obj has a constructed state, it must * be in this state _before_ it is released. Called with disabled ints. */ -static inline void __cache_free(struct kmem_cache *cachep, void *objp, - unsigned long caller) +static __always_inline void __cache_free(struct kmem_cache *cachep, void *objp, + unsigned long caller) { /* Put the object into the quarantine, don't touch it for now. */ - if (kasan_slab_free(cachep, objp)) + if (kasan_slab_free(cachep, objp, _RET_IP_)) return; ___cache_free(cachep, objp, caller); diff --git a/mm/slub.c b/mm/slub.c index 67c8cee43cf6..b1e41572c6cb 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1354,13 +1354,13 @@ static inline void kmalloc_large_node_hook(void *ptr, size_t size, gfp_t flags) kasan_kmalloc_large(ptr, size, flags); } -static inline void kfree_hook(void *x) +static __always_inline void kfree_hook(void *x) { kmemleak_free(x); - kasan_kfree_large(x); + kasan_kfree_large(x, _RET_IP_); } -static inline void *slab_free_hook(struct kmem_cache *s, void *x) +static __always_inline void *slab_free_hook(struct kmem_cache *s, void *x) { void *freeptr; @@ -1388,7 +1388,7 @@ static inline void *slab_free_hook(struct kmem_cache *s, void *x) * kasan_slab_free() may put x into memory quarantine, delaying its * reuse. In this case the object's freelist pointer is changed. */ - kasan_slab_free(s, x); + kasan_slab_free(s, x, _RET_IP_); return freeptr; } -- 2.15.1.620.gb9897f4670-goog
