Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 21:21:41 +00:00
Code Issues Packages Projects Releases Wiki Activity
f30adc0d33
linux/mm/kasan/kasan.h
Kuan-Ying Lee 3de0de7580 kasan: separate double free case from invalid free 
Currently, KASAN describes all invalid-free/double-free bugs as
"double-free or invalid-free".  This is ambiguous.

KASAN should report "double-free" when a double-free is a more likely
cause (the address points to the start of an object) and report
"invalid-free" otherwise [1].

[1] https://bugzilla.kernel.org/show_bug.cgi?id=212193

Link: https://lkml.kernel.org/r/20220615062219.22618-1-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Cc: Andrew Yang <andrew.yang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:33 -07:00

570 lines
17 KiB
C
Raw Blame History

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __MM_KASAN_KASAN_H
#define __MM_KASAN_KASAN_H
#include <linux/kasan.h>
#include <linux/kasan-tags.h>
#include <linux/kfence.h>
#include <linux/stackdepot.h>
#ifdef CONFIG_KASAN_HW_TAGS
#include <linux/static_key.h>
#include "../slab.h"
DECLARE_STATIC_KEY_TRUE(kasan_flag_vmalloc);
DECLARE_STATIC_KEY_TRUE(kasan_flag_stacktrace);
enum kasan_mode {
KASAN_MODE_SYNC,
KASAN_MODE_ASYNC,
KASAN_MODE_ASYMM,
};
extern enum kasan_mode kasan_mode __ro_after_init;
static inline bool kasan_vmalloc_enabled(void)
{
return static_branch_likely(&kasan_flag_vmalloc);
}
static inline bool kasan_stack_collection_enabled(void)
{
return static_branch_unlikely(&kasan_flag_stacktrace);
}
static inline bool kasan_async_fault_possible(void)
{
return kasan_mode == KASAN_MODE_ASYNC || kasan_mode == KASAN_MODE_ASYMM;
}
static inline bool kasan_sync_fault_possible(void)
{
return kasan_mode == KASAN_MODE_SYNC || kasan_mode == KASAN_MODE_ASYMM;
}
#else
static inline bool kasan_stack_collection_enabled(void)
{
return true;
}
static inline bool kasan_async_fault_possible(void)
{
return false;
}
static inline bool kasan_sync_fault_possible(void)
{
return true;
}
#endif
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
#define KASAN_GRANULE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
#else
#include <asm/mte-kasan.h>
#define KASAN_GRANULE_SIZE MTE_GRANULE_SIZE
#endif
#define KASAN_GRANULE_MASK (KASAN_GRANULE_SIZE - 1)
#define KASAN_MEMORY_PER_SHADOW_PAGE (KASAN_GRANULE_SIZE << PAGE_SHIFT)
#ifdef CONFIG_KASAN_GENERIC
#define KASAN_PAGE_FREE 0xFF /* freed page */
#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocation */
#define KASAN_SLAB_REDZONE 0xFC /* redzone for slab object */
#define KASAN_SLAB_FREE 0xFB /* freed slab object */
#define KASAN_VMALLOC_INVALID 0xF8 /* inaccessible space in vmap area */
#else
#define KASAN_PAGE_FREE KASAN_TAG_INVALID
#define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
#define KASAN_SLAB_REDZONE KASAN_TAG_INVALID
#define KASAN_SLAB_FREE KASAN_TAG_INVALID
#define KASAN_VMALLOC_INVALID KASAN_TAG_INVALID /* only used for SW_TAGS */
#endif
#ifdef CONFIG_KASAN_GENERIC
#define KASAN_SLAB_FREETRACK 0xFA /* freed slab object with free track */
#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
/* Stack redzone shadow values. Compiler ABI, do not change. */
#define KASAN_STACK_LEFT 0xF1
#define KASAN_STACK_MID 0xF2
#define KASAN_STACK_RIGHT 0xF3
#define KASAN_STACK_PARTIAL 0xF4
/* alloca redzone shadow values. */
#define KASAN_ALLOCA_LEFT 0xCA
#define KASAN_ALLOCA_RIGHT 0xCB
/* alloca redzone size. Compiler ABI, do not change. */
#define KASAN_ALLOCA_REDZONE_SIZE 32
/* Stack frame marker. Compiler ABI, do not change. */
#define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3
/* Dummy value to avoid breaking randconfig/all*config builds. */
#ifndef KASAN_ABI_VERSION
#define KASAN_ABI_VERSION 1
#endif
#endif /* CONFIG_KASAN_GENERIC */
/* Metadata layout customization. */
#define META_BYTES_PER_BLOCK 1
#define META_BLOCKS_PER_ROW 16
#define META_BYTES_PER_ROW (META_BLOCKS_PER_ROW * META_BYTES_PER_BLOCK)
#define META_MEM_BYTES_PER_ROW (META_BYTES_PER_ROW * KASAN_GRANULE_SIZE)
#define META_ROWS_AROUND_ADDR 2
enum kasan_report_type {
KASAN_REPORT_ACCESS,
KASAN_REPORT_INVALID_FREE,
KASAN_REPORT_DOUBLE_FREE,
};
struct kasan_report_info {
enum kasan_report_type type;
void *access_addr;
void *first_bad_addr;
size_t access_size;
bool is_write;
unsigned long ip;
};
/* Do not change the struct layout: compiler ABI. */
struct kasan_source_location {
const char *filename;
int line_no;
int column_no;
};
/* Do not change the struct layout: compiler ABI. */
struct kasan_global {
const void *beg; /* Address of the beginning of the global variable. */
size_t size; /* Size of the global variable. */
size_t size_with_redzone; /* Size of the variable + size of the redzone. 32 bytes aligned. */
const void *name;
const void *module_name; /* Name of the module where the global variable is declared. */
unsigned long has_dynamic_init; /* This is needed for C++. */
#if KASAN_ABI_VERSION >= 4
struct kasan_source_location *location;
#endif
#if KASAN_ABI_VERSION >= 5
char *odr_indicator;
#endif
};
/* Structures for keeping alloc and free tracks. */
#define KASAN_STACK_DEPTH 64
struct kasan_track {
u32 pid;
depot_stack_handle_t stack;
};
#if defined(CONFIG_KASAN_TAGS_IDENTIFY) && defined(CONFIG_KASAN_SW_TAGS)
#define KASAN_NR_FREE_STACKS 5
#else
#define KASAN_NR_FREE_STACKS 1
#endif
struct kasan_alloc_meta {
struct kasan_track alloc_track;
/* Generic mode stores free track in kasan_free_meta. */
#ifdef CONFIG_KASAN_GENERIC
depot_stack_handle_t aux_stack[2];
#else
struct kasan_track free_track[KASAN_NR_FREE_STACKS];
#endif
#ifdef CONFIG_KASAN_TAGS_IDENTIFY
u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
u8 free_track_idx;
#endif
};
struct qlist_node {
struct qlist_node *next;
};
/*
* Free meta is stored either in the object itself or in the redzone after the
* object. In the former case, free meta offset is 0. In the latter case, the
* offset is between 0 and INT_MAX. INT_MAX marks that free meta is not present.
*/
#define KASAN_NO_FREE_META INT_MAX
/*
* Free meta is only used by Generic mode while the object is in quarantine.
* After that, slab allocator stores the freelist pointer in the object.
*/
struct kasan_free_meta {
#ifdef CONFIG_KASAN_GENERIC
struct qlist_node quarantine_link;
struct kasan_track free_track;
#endif
};
#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
/* Used in KUnit-compatible KASAN tests. */
struct kunit_kasan_status {
bool report_found;
bool sync_fault;
};
#endif
struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache,
const void *object);
#ifdef CONFIG_KASAN_GENERIC
struct kasan_free_meta *kasan_get_free_meta(struct kmem_cache *cache,
const void *object);
#endif
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
static inline const void *kasan_shadow_to_mem(const void *shadow_addr)
{
return (void *)(((unsigned long)shadow_addr - KASAN_SHADOW_OFFSET)
<< KASAN_SHADOW_SCALE_SHIFT);
}
static inline bool addr_has_metadata(const void *addr)
{
return (kasan_reset_tag(addr) >=
kasan_shadow_to_mem((void *)KASAN_SHADOW_START));
}
/**
* kasan_check_range - Check memory region, and report if invalid access.
* @addr: the accessed address
* @size: the accessed size
* @write: true if access is a write access
* @ret_ip: return address
* @return: true if access was valid, false if invalid
*/
bool kasan_check_range(unsigned long addr, size_t size, bool write,
unsigned long ret_ip);
#else /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
static inline bool addr_has_metadata(const void *addr)
{
return (is_vmalloc_addr(addr) || virt_addr_valid(addr));
}
#endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */
#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
void kasan_print_tags(u8 addr_tag, const void *addr);
#else
static inline void kasan_print_tags(u8 addr_tag, const void *addr) { }
#endif
void *kasan_find_first_bad_addr(void *addr, size_t size);
const char *kasan_get_bug_type(struct kasan_report_info *info);
void kasan_metadata_fetch_row(char *buffer, void *row);
#if defined(CONFIG_KASAN_STACK)
void kasan_print_address_stack_frame(const void *addr);
#else
static inline void kasan_print_address_stack_frame(const void *addr) { }
#endif
bool kasan_report(unsigned long addr, size_t size,
bool is_write, unsigned long ip);
void kasan_report_invalid_free(void *object, unsigned long ip, enum kasan_report_type type);
struct page *kasan_addr_to_page(const void *addr);
struct slab *kasan_addr_to_slab(const void *addr);
depot_stack_handle_t kasan_save_stack(gfp_t flags, bool can_alloc);
void kasan_set_track(struct kasan_track *track, gfp_t flags);
void kasan_set_free_info(struct kmem_cache *cache, void *object, u8 tag);
struct kasan_track *kasan_get_free_track(struct kmem_cache *cache,
void *object, u8 tag);
#if defined(CONFIG_KASAN_GENERIC) && \
(defined(CONFIG_SLAB) || defined(CONFIG_SLUB))
bool kasan_quarantine_put(struct kmem_cache *cache, void *object);
void kasan_quarantine_reduce(void);
void kasan_quarantine_remove_cache(struct kmem_cache *cache);
#else
static inline bool kasan_quarantine_put(struct kmem_cache *cache, void *object) { return false; }
static inline void kasan_quarantine_reduce(void) { }
static inline void kasan_quarantine_remove_cache(struct kmem_cache *cache) { }
#endif
#ifndef arch_kasan_set_tag
static inline const void *arch_kasan_set_tag(const void *addr, u8 tag)
{
return addr;
}
#endif
#ifndef arch_kasan_get_tag
#define arch_kasan_get_tag(addr) 0
#endif
#define set_tag(addr, tag) ((void *)arch_kasan_set_tag((addr), (tag)))
#define get_tag(addr) arch_kasan_get_tag(addr)
#ifdef CONFIG_KASAN_HW_TAGS
#ifndef arch_enable_tagging_sync
#define arch_enable_tagging_sync()
#endif
#ifndef arch_enable_tagging_async
#define arch_enable_tagging_async()
#endif
#ifndef arch_enable_tagging_asymm
#define arch_enable_tagging_asymm()
#endif
#ifndef arch_force_async_tag_fault
#define arch_force_async_tag_fault()
#endif
#ifndef arch_get_random_tag
#define arch_get_random_tag() (0xFF)
#endif
#ifndef arch_get_mem_tag
#define arch_get_mem_tag(addr) (0xFF)
#endif
#ifndef arch_set_mem_tag_range
#define arch_set_mem_tag_range(addr, size, tag, init) ((void *)(addr))
#endif
#define hw_enable_tagging_sync() arch_enable_tagging_sync()
#define hw_enable_tagging_async() arch_enable_tagging_async()
#define hw_enable_tagging_asymm() arch_enable_tagging_asymm()
#define hw_force_async_tag_fault() arch_force_async_tag_fault()
#define hw_get_random_tag() arch_get_random_tag()
#define hw_get_mem_tag(addr) arch_get_mem_tag(addr)
#define hw_set_mem_tag_range(addr, size, tag, init) \
arch_set_mem_tag_range((addr), (size), (tag), (init))
void kasan_enable_tagging(void);
#else /* CONFIG_KASAN_HW_TAGS */
#define hw_enable_tagging_sync()
#define hw_enable_tagging_async()
#define hw_enable_tagging_asymm()
static inline void kasan_enable_tagging(void) { }
#endif /* CONFIG_KASAN_HW_TAGS */
#if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
void kasan_force_async_fault(void);
#else /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
static inline void kasan_force_async_fault(void) { }
#endif /* CONFIG_KASAN_HW_TAGS && CONFIG_KASAN_KUNIT_TEST */
#ifdef CONFIG_KASAN_SW_TAGS
u8 kasan_random_tag(void);
#elif defined(CONFIG_KASAN_HW_TAGS)
static inline u8 kasan_random_tag(void) { return hw_get_random_tag(); }
#else
static inline u8 kasan_random_tag(void) { return 0; }
#endif
#ifdef CONFIG_KASAN_HW_TAGS
static inline void kasan_poison(const void *addr, size_t size, u8 value, bool init)
{
addr = kasan_reset_tag(addr);
/* Skip KFENCE memory if called explicitly outside of sl*b. */
if (is_kfence_address(addr))
return;
if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
return;
if (WARN_ON(size & KASAN_GRANULE_MASK))
return;
hw_set_mem_tag_range((void *)addr, size, value, init);
}
static inline void kasan_unpoison(const void *addr, size_t size, bool init)
{
u8 tag = get_tag(addr);
addr = kasan_reset_tag(addr);
/* Skip KFENCE memory if called explicitly outside of sl*b. */
if (is_kfence_address(addr))
return;
if (WARN_ON((unsigned long)addr & KASAN_GRANULE_MASK))
return;
/*
* Explicitly initialize the memory with the precise object size to
* avoid overwriting the slab redzone. This disables initialization in
* the arch code and may thus lead to performance penalty. This penalty
* does not affect production builds, as slab redzones are not enabled
* there.
*/
if (__slub_debug_enabled() &&
init && ((unsigned long)size & KASAN_GRANULE_MASK)) {
init = false;
memzero_explicit((void *)addr, size);
}
size = round_up(size, KASAN_GRANULE_SIZE);
hw_set_mem_tag_range((void *)addr, size, tag, init);
}
static inline bool kasan_byte_accessible(const void *addr)
{
u8 ptr_tag = get_tag(addr);
u8 mem_tag = hw_get_mem_tag((void *)addr);
return ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag;
}
#else /* CONFIG_KASAN_HW_TAGS */
/**
* kasan_poison - mark the memory range as inaccessible
* @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
* @size - range size, must be aligned to KASAN_GRANULE_SIZE
* @value - value that's written to metadata for the range
* @init - whether to initialize the memory range (only for hardware tag-based)
*
* The size gets aligned to KASAN_GRANULE_SIZE before marking the range.
*/
void kasan_poison(const void *addr, size_t size, u8 value, bool init);
/**
* kasan_unpoison - mark the memory range as accessible
* @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
* @size - range size, can be unaligned
* @init - whether to initialize the memory range (only for hardware tag-based)
*
* For the tag-based modes, the @size gets aligned to KASAN_GRANULE_SIZE before
* marking the range.
* For the generic mode, the last granule of the memory range gets partially
* unpoisoned based on the @size.
*/
void kasan_unpoison(const void *addr, size_t size, bool init);
bool kasan_byte_accessible(const void *addr);
#endif /* CONFIG_KASAN_HW_TAGS */
#ifdef CONFIG_KASAN_GENERIC
/**
* kasan_poison_last_granule - mark the last granule of the memory range as
* inaccessible
* @addr - range start address, must be aligned to KASAN_GRANULE_SIZE
* @size - range size
*
* This function is only available for the generic mode, as it's the only mode
* that has partially poisoned memory granules.
*/
void kasan_poison_last_granule(const void *address, size_t size);
#else /* CONFIG_KASAN_GENERIC */
static inline void kasan_poison_last_granule(const void *address, size_t size) { }
#endif /* CONFIG_KASAN_GENERIC */
#ifndef kasan_arch_is_ready
static inline bool kasan_arch_is_ready(void) { return true; }
#elif !defined(CONFIG_KASAN_GENERIC) || !defined(CONFIG_KASAN_OUTLINE)
#error kasan_arch_is_ready only works in KASAN generic outline mode!
#endif
#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) || IS_ENABLED(CONFIG_KASAN_MODULE_TEST)
bool kasan_save_enable_multi_shot(void);
void kasan_restore_multi_shot(bool enabled);
#endif
/*
* Exported functions for interfaces called from assembly or from generated
* code. Declared here to avoid warnings about missing declarations.
*/
asmlinkage void kasan_unpoison_task_stack_below(const void *watermark);
void __asan_register_globals(struct kasan_global *globals, size_t size);
void __asan_unregister_globals(struct kasan_global *globals, size_t size);
void __asan_handle_no_return(void);
void __asan_alloca_poison(unsigned long addr, size_t size);
void __asan_allocas_unpoison(const void *stack_top, const void *stack_bottom);
void __asan_load1(unsigned long addr);
void __asan_store1(unsigned long addr);
void __asan_load2(unsigned long addr);
void __asan_store2(unsigned long addr);
void __asan_load4(unsigned long addr);
void __asan_store4(unsigned long addr);
void __asan_load8(unsigned long addr);
void __asan_store8(unsigned long addr);
void __asan_load16(unsigned long addr);
void __asan_store16(unsigned long addr);
void __asan_loadN(unsigned long addr, size_t size);
void __asan_storeN(unsigned long addr, size_t size);
void __asan_load1_noabort(unsigned long addr);
void __asan_store1_noabort(unsigned long addr);
void __asan_load2_noabort(unsigned long addr);
void __asan_store2_noabort(unsigned long addr);
void __asan_load4_noabort(unsigned long addr);
void __asan_store4_noabort(unsigned long addr);
void __asan_load8_noabort(unsigned long addr);
void __asan_store8_noabort(unsigned long addr);
void __asan_load16_noabort(unsigned long addr);
void __asan_store16_noabort(unsigned long addr);
void __asan_loadN_noabort(unsigned long addr, size_t size);
void __asan_storeN_noabort(unsigned long addr, size_t size);
void __asan_report_load1_noabort(unsigned long addr);
void __asan_report_store1_noabort(unsigned long addr);
void __asan_report_load2_noabort(unsigned long addr);
void __asan_report_store2_noabort(unsigned long addr);
void __asan_report_load4_noabort(unsigned long addr);
void __asan_report_store4_noabort(unsigned long addr);
void __asan_report_load8_noabort(unsigned long addr);
void __asan_report_store8_noabort(unsigned long addr);
void __asan_report_load16_noabort(unsigned long addr);
void __asan_report_store16_noabort(unsigned long addr);
void __asan_report_load_n_noabort(unsigned long addr, size_t size);
void __asan_report_store_n_noabort(unsigned long addr, size_t size);
void __asan_set_shadow_00(const void *addr, size_t size);
void __asan_set_shadow_f1(const void *addr, size_t size);
void __asan_set_shadow_f2(const void *addr, size_t size);
void __asan_set_shadow_f3(const void *addr, size_t size);
void __asan_set_shadow_f5(const void *addr, size_t size);
void __asan_set_shadow_f8(const void *addr, size_t size);
void __hwasan_load1_noabort(unsigned long addr);
void __hwasan_store1_noabort(unsigned long addr);
void __hwasan_load2_noabort(unsigned long addr);
void __hwasan_store2_noabort(unsigned long addr);
void __hwasan_load4_noabort(unsigned long addr);
void __hwasan_store4_noabort(unsigned long addr);
void __hwasan_load8_noabort(unsigned long addr);
void __hwasan_store8_noabort(unsigned long addr);
void __hwasan_load16_noabort(unsigned long addr);
void __hwasan_store16_noabort(unsigned long addr);
void __hwasan_loadN_noabort(unsigned long addr, size_t size);
void __hwasan_storeN_noabort(unsigned long addr, size_t size);
void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);
#endif /* __MM_KASAN_KASAN_H */
Reference in New Issue View Git Blame Copy Permalink