linux/mm/kasan/kasan.h
Andrey Konovalov cde8a7eb77 kasan: ensure poisoning size alignment
A previous changes d99f6a10c1 ("kasan: don't round_up too much")
attempted to simplify the code by adding a round_up(size) call into
kasan_poison().  While this allows to have less round_up() calls around
the code, this results in round_up() being called multiple times.

This patch removes round_up() of size from kasan_poison() and ensures that
all callers round_up() the size explicitly.  This patch also adds
WARN_ON() alignment checks for address and size to kasan_poison() and
kasan_unpoison().

Link: https://lkml.kernel.org/r/3ffe8d4a246ae67a8b5e91f65bf98cd7cba9d7b9.1612546384.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:03 -08:00

495 lines
15 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __MM_KASAN_KASAN_H
#define __MM_KASAN_KASAN_H
#include <linux/kasan.h>
#include <linux/kfence.h>
#include <linux/stackdepot.h>
#ifdef CONFIG_KASAN_HW_TAGS
#include <linux/static_key.h>
DECLARE_STATIC_KEY_FALSE(kasan_flag_stacktrace);
static inline bool kasan_stack_collection_enabled(void)
{
return static_branch_unlikely(&kasan_flag_stacktrace);
}
#else
static inline bool kasan_stack_collection_enabled(void)
{
return true;
}
#endif
extern bool kasan_flag_panic __ro_after_init;
#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)
#define KASAN_TAG_KERNEL 0xFF /* native kernel pointers tag */
#define KASAN_TAG_INVALID 0xFE /* inaccessible memory tag */
#define KASAN_TAG_MAX 0xFD /* maximum value for random tags */
#ifdef CONFIG_KASAN_HW_TAGS
#define KASAN_TAG_MIN 0xF0 /* mimimum value for random tags */
#else
#define KASAN_TAG_MIN 0x00 /* mimimum value for random tags */
#endif
#ifdef CONFIG_KASAN_GENERIC
#define KASAN_FREE_PAGE 0xFF /* page was freed */
#define KASAN_PAGE_REDZONE 0xFE /* redzone for kmalloc_large allocations */
#define KASAN_KMALLOC_REDZONE 0xFC /* redzone inside slub object */
#define KASAN_KMALLOC_FREE 0xFB /* object was freed (kmem_cache_free/kfree) */
#define KASAN_KMALLOC_FREETRACK 0xFA /* object was freed and has free track set */
#else
#define KASAN_FREE_PAGE KASAN_TAG_INVALID
#define KASAN_PAGE_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_REDZONE KASAN_TAG_INVALID
#define KASAN_KMALLOC_FREE KASAN_TAG_INVALID
#define KASAN_KMALLOC_FREETRACK KASAN_TAG_INVALID
#endif
#define KASAN_GLOBAL_REDZONE 0xF9 /* redzone for global variable */
#define KASAN_VMALLOC_INVALID 0xF8 /* unallocated space in vmapped page */
/*
* Stack redzone shadow values
* (Those are compiler's ABI, don't change them)
*/
#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
#define KASAN_ALLOCA_REDZONE_SIZE 32
/*
* Stack frame marker (compiler ABI).
*/
#define KASAN_CURRENT_STACK_FRAME_MAGIC 0x41B58AB3
/* Don't break randconfig/all*config builds */
#ifndef KASAN_ABI_VERSION
#define KASAN_ABI_VERSION 1
#endif
/* 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
struct kasan_access_info {
const void *access_addr;
const void *first_bad_addr;
size_t access_size;
bool is_write;
unsigned long ip;
};
/* The layout of struct dictated by compiler */
struct kasan_source_location {
const char *filename;
int line_no;
int column_no;
};
/* The layout of struct dictated by compiler */
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 red zone. 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 needed for C++ */
#if KASAN_ABI_VERSION >= 4
struct kasan_source_location *location;
#endif
#if KASAN_ABI_VERSION >= 5
char *odr_indicator;
#endif
};
/**
* Structures to keep alloc and free tracks *
*/
#define KASAN_STACK_DEPTH 64
struct kasan_track {
u32 pid;
depot_stack_handle_t stack;
};
#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
#define KASAN_NR_FREE_STACKS 5
#else
#define KASAN_NR_FREE_STACKS 1
#endif
struct kasan_alloc_meta {
struct kasan_track alloc_track;
#ifdef CONFIG_KASAN_GENERIC
/*
* call_rcu() call stack is stored into struct kasan_alloc_meta.
* The free stack is stored into struct kasan_free_meta.
*/
depot_stack_handle_t aux_stack[2];
#else
struct kasan_track free_track[KASAN_NR_FREE_STACKS];
#endif
#ifdef CONFIG_KASAN_SW_TAGS_IDENTIFY
u8 free_pointer_tag[KASAN_NR_FREE_STACKS];
u8 free_track_idx;
#endif
};
struct qlist_node {
struct qlist_node *next;
};
/*
* Generic mode either stores free meta in the object itself or in the redzone
* after the object. In the former case free meta offset is 0, in the latter
* case it has some sane value smaller than INT_MAX. Use INT_MAX as free meta
* offset when free meta isn't present.
*/
#define KASAN_NO_FREE_META INT_MAX
struct kasan_free_meta {
#ifdef CONFIG_KASAN_GENERIC
/* This field is used while the object is in the quarantine.
* Otherwise it might be used for the allocator freelist.
*/
struct qlist_node quarantine_link;
struct kasan_track free_track;
#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 (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_access_info *info);
void kasan_metadata_fetch_row(char *buffer, void *row);
#if defined(CONFIG_KASAN_GENERIC) && 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);
struct page *kasan_addr_to_page(const void *addr);
depot_stack_handle_t kasan_save_stack(gfp_t flags);
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
#define arch_enable_tagging()
#endif
#ifndef arch_init_tags
#define arch_init_tags(max_tag)
#endif
#ifndef arch_set_tagging_report_once
#define arch_set_tagging_report_once(state)
#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) ((void *)(addr))
#endif
#define hw_enable_tagging() arch_enable_tagging()
#define hw_init_tags(max_tag) arch_init_tags(max_tag)
#define hw_set_tagging_report_once(state) arch_set_tagging_report_once(state)
#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) arch_set_mem_tag_range((addr), (size), (tag))
#else /* CONFIG_KASAN_HW_TAGS */
#define hw_enable_tagging()
#define hw_set_tagging_report_once(state)
#endif /* CONFIG_KASAN_HW_TAGS */
#if defined(CONFIG_KASAN_HW_TAGS) && IS_ENABLED(CONFIG_KASAN_KUNIT_TEST)
void kasan_set_tagging_report_once(bool state);
void kasan_enable_tagging(void);
#else /* CONFIG_KASAN_HW_TAGS || CONFIG_KASAN_KUNIT_TEST */
static inline void kasan_set_tagging_report_once(bool state) { }
static inline void kasan_enable_tagging(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)
{
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);
}
static inline void kasan_unpoison(const void *addr, size_t size)
{
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;
size = round_up(size, KASAN_GRANULE_SIZE);
hw_set_mem_tag_range((void *)addr, size, tag);
}
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 (mem_tag != KASAN_TAG_INVALID) &&
(ptr_tag == KASAN_TAG_KERNEL || ptr_tag == mem_tag);
}
#else /* CONFIG_KASAN_HW_TAGS */
/**
* kasan_poison - mark the memory range as unaccessible
* @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
*
* The size gets aligned to KASAN_GRANULE_SIZE before marking the range.
*/
void kasan_poison(const void *addr, size_t size, u8 value);
/**
* 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
*
* 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 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
* unaccessible
* @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 */
/*
* Exported functions for interfaces called from assembly or from generated
* code. Declarations here to avoid warning 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