From: Kuan-Ying Lee <Kuan-Ying.Lee@xxxxxxxxxxxx> Subject: kasan: integrate the common part of two KASAN tag-based modes 1. Move kasan_get_free_track() and kasan_set_free_info() into tags.c and combine these two functions for SW_TAGS and HW_TAGS kasan mode. 2. Move kasan_get_bug_type() to report_tags.c and make this function compatible for SW_TAGS and HW_TAGS kasan mode. Link: https://lkml.kernel.org/r/20210626100931.22794-3-Kuan-Ying.Lee@xxxxxxxxxxxx Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@xxxxxxxxxxxx> Suggested-by: Marco Elver <elver@xxxxxxxxxx> Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Chinwen Chang <chinwen.chang@xxxxxxxxxxxx> Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx> Cc: Nicholas Tang <nicholas.tang@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/kasan/Makefile | 4 +- mm/kasan/hw_tags.c | 22 ------------- mm/kasan/report_hw_tags.c | 5 --- mm/kasan/report_sw_tags.c | 43 -------------------------- mm/kasan/report_tags.c | 51 +++++++++++++++++++++++++++++++ mm/kasan/sw_tags.c | 41 ------------------------- mm/kasan/tags.c | 59 ++++++++++++++++++++++++++++++++++++ 7 files changed, 112 insertions(+), 113 deletions(-) --- a/mm/kasan/hw_tags.c~kasan-integrate-the-common-part-of-two-kasan-tag-based-modes +++ a/mm/kasan/hw_tags.c @@ -216,28 +216,6 @@ void __init kasan_init_hw_tags(void) pr_info("KernelAddressSanitizer initialized\n"); } -void kasan_set_free_info(struct kmem_cache *cache, - void *object, u8 tag) -{ - struct kasan_alloc_meta *alloc_meta; - - alloc_meta = kasan_get_alloc_meta(cache, object); - if (alloc_meta) - kasan_set_track(&alloc_meta->free_track[0], GFP_NOWAIT); -} - -struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, - void *object, u8 tag) -{ - struct kasan_alloc_meta *alloc_meta; - - alloc_meta = kasan_get_alloc_meta(cache, object); - if (!alloc_meta) - return NULL; - - return &alloc_meta->free_track[0]; -} - #if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) void kasan_set_tagging_report_once(bool state) --- a/mm/kasan/Makefile~kasan-integrate-the-common-part-of-two-kasan-tag-based-modes +++ a/mm/kasan/Makefile @@ -37,5 +37,5 @@ CFLAGS_sw_tags.o := $(CC_FLAGS_KASAN_RUN obj-$(CONFIG_KASAN) := common.o report.o obj-$(CONFIG_KASAN_GENERIC) += init.o generic.o report_generic.o shadow.o quarantine.o -obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o -obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o +obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o tags.o report_tags.o +obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o tags.o report_tags.o --- a/mm/kasan/report_hw_tags.c~kasan-integrate-the-common-part-of-two-kasan-tag-based-modes +++ a/mm/kasan/report_hw_tags.c @@ -15,11 +15,6 @@ #include "kasan.h" -const char *kasan_get_bug_type(struct kasan_access_info *info) -{ - return "invalid-access"; -} - void *kasan_find_first_bad_addr(void *addr, size_t size) { return kasan_reset_tag(addr); --- a/mm/kasan/report_sw_tags.c~kasan-integrate-the-common-part-of-two-kasan-tag-based-modes +++ a/mm/kasan/report_sw_tags.c @@ -29,49 +29,6 @@ #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"; -} - void *kasan_find_first_bad_addr(void *addr, size_t size) { u8 tag = get_tag(addr); --- /dev/null +++ a/mm/kasan/report_tags.c @@ -0,0 +1,51 @@ +// 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"; +} --- a/mm/kasan/sw_tags.c~kasan-integrate-the-common-part-of-two-kasan-tag-based-modes +++ a/mm/kasan/sw_tags.c @@ -166,44 +166,3 @@ void __hwasan_tag_memory(unsigned long a kasan_poison((void *)addr, size, tag, false); } EXPORT_SYMBOL(__hwasan_tag_memory); - -void kasan_set_free_info(struct kmem_cache *cache, - void *object, u8 tag) -{ - struct kasan_alloc_meta *alloc_meta; - u8 idx = 0; - - alloc_meta = kasan_get_alloc_meta(cache, object); - if (!alloc_meta) - return; - -#ifdef CONFIG_KASAN_TAGS_IDENTIFY - idx = alloc_meta->free_track_idx; - alloc_meta->free_pointer_tag[idx] = tag; - alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS; -#endif - - kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT); -} - -struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, - void *object, u8 tag) -{ - struct kasan_alloc_meta *alloc_meta; - int i = 0; - - alloc_meta = kasan_get_alloc_meta(cache, object); - if (!alloc_meta) - return NULL; - -#ifdef CONFIG_KASAN_TAGS_IDENTIFY - for (i = 0; i < KASAN_NR_FREE_STACKS; i++) { - if (alloc_meta->free_pointer_tag[i] == tag) - break; - } - if (i == KASAN_NR_FREE_STACKS) - i = alloc_meta->free_track_idx; -#endif - - return &alloc_meta->free_track[i]; -} --- /dev/null +++ a/mm/kasan/tags.c @@ -0,0 +1,59 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This file contains common tag-based KASAN code. + * + * Copyright (c) 2018 Google, Inc. + * Copyright (c) 2020 Google, Inc. + */ + +#include <linux/init.h> +#include <linux/kasan.h> +#include <linux/kernel.h> +#include <linux/memory.h> +#include <linux/mm.h> +#include <linux/static_key.h> +#include <linux/string.h> +#include <linux/types.h> + +#include "kasan.h" + +void kasan_set_free_info(struct kmem_cache *cache, + void *object, u8 tag) +{ + struct kasan_alloc_meta *alloc_meta; + u8 idx = 0; + + alloc_meta = kasan_get_alloc_meta(cache, object); + if (!alloc_meta) + return; + +#ifdef CONFIG_KASAN_TAGS_IDENTIFY + idx = alloc_meta->free_track_idx; + alloc_meta->free_pointer_tag[idx] = tag; + alloc_meta->free_track_idx = (idx + 1) % KASAN_NR_FREE_STACKS; +#endif + + kasan_set_track(&alloc_meta->free_track[idx], GFP_NOWAIT); +} + +struct kasan_track *kasan_get_free_track(struct kmem_cache *cache, + void *object, u8 tag) +{ + struct kasan_alloc_meta *alloc_meta; + int i = 0; + + alloc_meta = kasan_get_alloc_meta(cache, object); + if (!alloc_meta) + return NULL; + +#ifdef CONFIG_KASAN_TAGS_IDENTIFY + for (i = 0; i < KASAN_NR_FREE_STACKS; i++) { + if (alloc_meta->free_pointer_tag[i] == tag) + break; + } + if (i == KASAN_NR_FREE_STACKS) + i = alloc_meta->free_track_idx; +#endif + + return &alloc_meta->free_track[i]; +} _
