From d99f6a10c161227ae7a698470b1cff7b33734d4a Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Tue, 22 Dec 2020 12:03:17 -0800 Subject: kasan: don't round_up too much For hardware tag-based mode kasan_poison_memory() already rounds up the size. Do the same for software modes and remove round_up() from the common code. Link: https://lkml.kernel.org/r/47b232474f1f89dc072aeda0fa58daa6efade377.1606162397.git.andreyknvl@google.com Link: https://linux-review.googlesource.com/id/Ib397128fac6eba874008662b4964d65352db4aa4 Signed-off-by: Andrey Konovalov Reviewed-by: Dmitry Vyukov Reviewed-by: Marco Elver Tested-by: Vincenzo Frascino Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Branislav Rankov Cc: Catalin Marinas Cc: Evgenii Stepanov Cc: Kevin Brodsky Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/kasan/common.c | 8 ++------ mm/kasan/shadow.c | 1 + 2 files changed, 3 insertions(+), 6 deletions(-) (limited to 'mm/kasan') diff --git a/mm/kasan/common.c b/mm/kasan/common.c index d0f8d7a955cd..e3cfe156f693 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -213,9 +213,7 @@ void __kasan_unpoison_object_data(struct kmem_cache *cache, void *object) void __kasan_poison_object_data(struct kmem_cache *cache, void *object) { - poison_range(object, - round_up(cache->object_size, KASAN_GRANULE_SIZE), - KASAN_KMALLOC_REDZONE); + poison_range(object, cache->object_size, KASAN_KMALLOC_REDZONE); } /* @@ -288,7 +286,6 @@ static bool ____kasan_slab_free(struct kmem_cache *cache, void *object, { u8 tag; void *tagged_object; - unsigned long rounded_up_size; tag = get_tag(object); tagged_object = object; @@ -309,8 +306,7 @@ static bool ____kasan_slab_free(struct kmem_cache *cache, void *object, return true; } - rounded_up_size = round_up(cache->object_size, KASAN_GRANULE_SIZE); - poison_range(object, rounded_up_size, KASAN_KMALLOC_FREE); + poison_range(object, cache->object_size, KASAN_KMALLOC_FREE); if (!kasan_stack_collection_enabled()) return false; diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c index 44a2b748f9d3..7c2c08c55f32 100644 --- a/mm/kasan/shadow.c +++ b/mm/kasan/shadow.c @@ -82,6 +82,7 @@ void poison_range(const void *address, size_t size, u8 value) * addresses to this function. */ address = kasan_reset_tag(address); + size = round_up(size, KASAN_GRANULE_SIZE); shadow_start = kasan_mem_to_shadow(address); shadow_end = kasan_mem_to_shadow(address + size); -- cgit v1.2.3