| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (c) 2014 Samsung Electronics Co., Ltd. |
| * Copyright (c) 2020 Google, Inc. |
| */ |
| |
| #include "kasan.h" |
| #include "../slab.h" |
| |
| const char *kasan_get_bug_type(struct kasan_access_info *info) |
| { |
| #ifdef CONFIG_KASAN_TAGS_IDENTIFY |
| struct kasan_alloc_meta *alloc_meta; |
| struct kmem_cache *cache; |
| struct page *page; |
| const void *addr; |
| void *object; |
| u8 tag; |
| int i; |
| |
| tag = get_tag(info->access_addr); |
| addr = kasan_reset_tag(info->access_addr); |
| page = kasan_addr_to_page(addr); |
| if (page && PageSlab(page)) { |
| cache = page->slab_cache; |
| object = nearest_obj(cache, page, (void *)addr); |
| alloc_meta = kasan_get_alloc_meta(cache, object); |
| |
| if (alloc_meta) { |
| for (i = 0; i < KASAN_NR_FREE_STACKS; i++) { |
| if (alloc_meta->free_pointer_tag[i] == tag) |
| return "use-after-free"; |
| } |
| } |
| return "out-of-bounds"; |
| } |
| #endif |
| |
| /* |
| * If access_size is a negative number, then it has reason to be |
| * defined as out-of-bounds bug type. |
| * |
| * Casting negative numbers to size_t would indeed turn up as |
| * a large size_t and its value will be larger than ULONG_MAX/2, |
| * so that this can qualify as out-of-bounds. |
| */ |
| if (info->access_addr + info->access_size < info->access_addr) |
| return "out-of-bounds"; |
| |
| return "invalid-access"; |
| } |