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--- libmalloc/libmalloc-317.100.9/src/pguard_malloc.c
+++ /dev/null
@@ -1,1445 +0,0 @@
-/*
- * Copyright (c) 2020 Apple Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-#include "pguard_malloc.h"
-
-#include <TargetConditionals.h>
-#if !TARGET_OS_DRIVERKIT
-# include <dlfcn.h> // dladdr()
-#endif
-#include <mach/mach_time.h> // mach_absolute_time()
-#include <sys/codesign.h> // csops()
-
-#include "internal.h"
-
-
-#pragma mark -
-#pragma mark Types and Structures
-
-static const char * const slot_state_labels[] = {
- "unused", "allocated", "freed"
-};
-
-typedef enum {
- ss_unused,
- ss_allocated,
- ss_freed
-} slot_state_t;
-
-MALLOC_STATIC_ASSERT(ss_unused == 0, "unused encoded with 0");
-MALLOC_STATIC_ASSERT(ss_freed < (1 << 2), "enum encodable with 2 bits");
-
-typedef struct {
- slot_state_t state : 2;
- uint32_t metadata : 30; // metadata << slots, so borrowing 2 bits here is okay.
- uint16_t size;
- uint16_t offset;
-} slot_t;
-
-MALLOC_STATIC_ASSERT(PAGE_MAX_SIZE <= UINT16_MAX, "16 bits for page offsets");
-MALLOC_STATIC_ASSERT(sizeof(slot_t) == 8, "slot_t size");
-
-// typedef struct { ... } stack_trace_t;
-
-#define STACK_TRACE_SIZE (MALLOC_TARGET_64BIT ? 144 : 80)
-MALLOC_STATIC_ASSERT(sizeof(stack_trace_t) <= STACK_TRACE_SIZE, "stack_trace_t size");
-
-typedef struct {
- uint32_t slot;
- stack_trace_t alloc_trace;
- stack_trace_t dealloc_trace;
-} metadata_t;
-
-#define METADATA_SIZE (MALLOC_TARGET_64BIT ? 296 : 168)
-MALLOC_STATIC_ASSERT(sizeof(metadata_t) <= METADATA_SIZE, "metadata_t size");
-
-typedef struct {
- // Malloc zone
- malloc_zone_t malloc_zone;
- malloc_zone_t *wrapped_zone;
-
- // Configuration
- uint32_t num_slots;
- uint32_t max_allocations;
- uint32_t max_metadata;
- uint32_t sample_counter_range;
- boolean_t signal_handler;
- boolean_t debug_log;
- uint64_t debug_log_throttle_ms;
-
- // Quarantine
- size_t size;
- vm_address_t begin;
- vm_address_t end;
-
- // Metadata
- slot_t *slots;
- metadata_t *metadata;
- uint8_t padding[PAGE_MAX_SIZE];
-
- // Mutable state
- _malloc_lock_s lock;
- uint32_t num_allocations;
- uint32_t num_metadata;
- uint32_t rr_slot_index;
-
- // Statistics
- size_t size_in_use;
- size_t max_size_in_use;
- uint64_t last_log_time;
-} pguard_zone_t;
-
-MALLOC_STATIC_ASSERT(__offsetof(pguard_zone_t, malloc_zone) == 0,
- "pguard_zone_t instances must be usable as regular zones");
-MALLOC_STATIC_ASSERT(__offsetof(pguard_zone_t, padding) < PAGE_MAX_SIZE,
- "First page is mapped read-only");
-MALLOC_STATIC_ASSERT(__offsetof(pguard_zone_t, lock) >= PAGE_MAX_SIZE,
- "Mutable state is on separate page");
-MALLOC_STATIC_ASSERT(sizeof(pguard_zone_t) < (2 * PAGE_MAX_SIZE),
- "Zone fits on 2 pages");
-
-
-#pragma mark -
-#pragma mark Decider Functions
-
-// The "decider" functions are performance critical. They should be inlinable and must not lock.
-
-MALLOC_ALWAYS_INLINE
-static inline boolean_t
-is_full(pguard_zone_t *zone)
-{
- return zone->num_allocations == zone->max_allocations;
-}
-
-static uint32_t rand_uniform(uint32_t upper_bound);
-
-MALLOC_ALWAYS_INLINE
-static inline boolean_t
-should_sample_counter(uint32_t counter_range)
-{
- MALLOC_STATIC_ASSERT(sizeof(void *) >= sizeof(uint32_t), "Pointer is used as 32bit counter");
- uint32_t counter = (uint32_t)_os_tsd_get_direct(__TSD_MALLOC_PGUARD_SAMPLE_COUNTER);
- // 0 -> regenerate counter; 1 -> sample allocation
- if (counter == 0) {
- counter = rand_uniform(counter_range);
- } else {
- counter--;
- }
- _os_tsd_set_direct(__TSD_MALLOC_PGUARD_SAMPLE_COUNTER, (void *)(uintptr_t)counter);
- return counter == 0;
-}
-
-MALLOC_ALWAYS_INLINE
-static inline boolean_t
-should_sample(pguard_zone_t *zone, size_t size)
-{
- boolean_t good_size = (size <= PAGE_SIZE);
- boolean_t not_full = !is_full(zone); // Optimization: racy check; we check again in allocate() for correctness.
- return good_size && not_full && should_sample_counter(zone->sample_counter_range);
-}
-
-MALLOC_ALWAYS_INLINE
-static inline boolean_t
-is_guarded(pguard_zone_t *zone, vm_address_t addr)
-{
- return zone->begin <= addr && addr < zone->end;
-}
-
-
-#pragma mark -
-#pragma mark Slot <-> Address Mapping
-
-static size_t
-quarantine_size(uint32_t num_slots)
-{
- return (2 * num_slots + 1) * PAGE_SIZE;
-}
-
-static vm_address_t
-page_addr(pguard_zone_t *zone, uint32_t slot)
-{
- MALLOC_ASSERT(slot < zone->num_slots);
- uint32_t page = 1 + 2 * slot;
- vm_offset_t offset = page * PAGE_SIZE;
- return zone->begin + offset;
-}
-
-static vm_address_t
-block_addr(pguard_zone_t *zone, uint32_t slot) {
- vm_address_t page = page_addr(zone, slot);
- uint16_t offset = zone->slots[slot].offset;
- return page + offset;
-}
-
-static uint32_t
-page_idx(pguard_zone_t *zone, vm_address_t addr)
-{
- MALLOC_ASSERT(is_guarded(zone, addr));
- vm_offset_t offset = addr - zone->begin;
- return (uint32_t)(offset / PAGE_SIZE);
-}
-
-static boolean_t
-is_guard_page(pguard_zone_t *zone, vm_address_t addr)
-{
- return page_idx(zone, addr) % 2 == 0;
-}
-
-
-#pragma mark -
-#pragma mark Slot Lookup
-
-static uint32_t
-nearest_slot(pguard_zone_t *zone, vm_address_t addr)
-{
- if (addr < (zone->begin + PAGE_SIZE)) {
- return 0;
- }
- if (addr >= (zone->end - PAGE_SIZE)) {
- return zone->num_slots - 1;
- }
-
- uint32_t page = page_idx(zone, addr);
- uint32_t slot = (page - 1) / 2;
- boolean_t guard_page = is_guard_page(zone, addr);
- boolean_t right_half = ((addr % PAGE_SIZE) >= (PAGE_SIZE / 2));
-
- if (guard_page && right_half) {
- slot++; // Round up.
- }
- return slot;
-}
-
-typedef enum {
- b_block_addr, // Canonical block address.
- b_valid, // Address within block.
- b_oob_slot, // Outside block, but within slot.
- b_oob_guard_page // Guard page.
-} bounds_status_t;
-
-typedef struct {
- uint32_t slot;
- bounds_status_t bounds : 31;
- boolean_t live_block_addr : 1; // Canonical block address for live allocation.
-} slot_lookup_t;
-
-MALLOC_STATIC_ASSERT(sizeof(slot_lookup_t) == 8, "slot_lookup_t size");
-
-static slot_lookup_t
-lookup_slot(pguard_zone_t *zone, vm_address_t addr)
-{
- MALLOC_ASSERT(is_guarded(zone, addr));
- MALLOC_ASSERT(zone->begin % PAGE_SIZE == 0);
-
- uint32_t slot = nearest_slot(zone, addr);
- uint16_t offset = (addr % PAGE_SIZE);
- uint16_t begin = zone->slots[slot].offset;
- uint16_t end = begin + zone->slots[slot].size;
-
- bounds_status_t bounds;
- if (is_guard_page(zone, addr)) {
- bounds = b_oob_guard_page;
- } else if (offset == begin) {
- bounds = b_block_addr;
- } else if (begin < offset && offset < end) {
- bounds = b_valid;
- } else {
- bounds = b_oob_slot;
- }
-
- boolean_t live_slot = (zone->slots[slot].state == ss_allocated);
- return (slot_lookup_t){
- .slot = slot,
- .bounds = bounds,
- .live_block_addr = (live_slot && bounds == b_block_addr)
- };
-}
-
-
-#pragma mark -
-#pragma mark Allocator Helpers
-
-// Darwin ABI requires 16 byte alignment.
-static const size_t k_min_alignment = 16;
-
-static size_t
-aligned_size(size_t size)
-{
- if (size == 0) {
- return k_min_alignment;
- }
- const size_t mask = (k_min_alignment - 1);
- return (size + mask) & ~mask;
-}
-
-// Current implementation: round-robin; delays reuse until at least (num_slots - max_allocations).
-// Possible alternatives: LRU, random.
-static uint32_t
-choose_available_slot(pguard_zone_t *zone)
-{
- uint32_t slot = zone->rr_slot_index;
- while (zone->slots[slot].state == ss_allocated) {
- slot = (slot + 1) % zone->num_slots;
- }
- // Delay reuse if immediately freed.
- zone->rr_slot_index = (slot + 1) % zone->num_slots;
- return slot;
-}
-
-static uint32_t
-choose_metadata(pguard_zone_t *zone)
-{
- if (zone->num_metadata < zone->max_metadata) {
- return zone->num_metadata++;
- }
-
- while (true) {
- uint32_t index = rand_uniform(zone->max_metadata);
- uint32_t s = zone->metadata[index].slot;
- if (zone->slots[s].state == ss_freed) {
- return index;
- }
- }
-}
-
-static boolean_t
-is_power_of_2(size_t n) {
- return __builtin_popcountl(n) == 1;
-}
-
-static uint16_t
-choose_offset_on_page(size_t size, size_t alignment, uint16_t page_size) {
- MALLOC_ASSERT(size <= page_size);
- MALLOC_ASSERT(alignment <= page_size && is_power_of_2(alignment));
- MALLOC_ASSERT(is_power_of_2(page_size));
- boolean_t left_align = rand_uniform(2);
- if (left_align) {
- return 0;
- }
- size_t mask = ~(alignment - 1);
- return (page_size - size) & mask;
-}
-
-
-#pragma mark -
-#pragma mark Allocator Functions
-
-MALLOC_ALWAYS_INLINE
-static inline void capture_trace(stack_trace_t *trace);
-
-static void mark_inaccessible(vm_address_t page);
-static void mark_read_write(vm_address_t page);
-static void log_zone_state(pguard_zone_t *zone, const char *type, vm_address_t addr);
-
-// Note: the functions below require locking.
-
-static size_t
-lookup_size(pguard_zone_t *zone, vm_address_t addr)
-{
- slot_lookup_t res = lookup_slot(zone, addr);
- if (!res.live_block_addr) {
- return 0;
- }
- return zone->slots[res.slot].size;
-}
-
-static vm_address_t
-allocate(pguard_zone_t *zone, size_t size, size_t alignment)
-{
- MALLOC_ASSERT(size <= PAGE_SIZE);
- MALLOC_ASSERT(k_min_alignment <= alignment && alignment <= PAGE_SIZE);
- MALLOC_ASSERT(is_power_of_2(alignment));
-
- if (is_full(zone)) {
- return (vm_address_t)NULL;
- }
-
- size = aligned_size(size);
- uint32_t slot = choose_available_slot(zone);
- uint32_t metadata = choose_metadata(zone);
- uint16_t offset = choose_offset_on_page(size, alignment, PAGE_SIZE);
-
- zone->slots[slot] = (slot_t){
- .state = ss_allocated,
- .metadata = metadata,
- .size = size,
- .offset = offset
- };
- zone->metadata[metadata].slot = slot;
- capture_trace(&zone->metadata[metadata].alloc_trace);
-
- vm_address_t page = page_addr(zone, slot);
- mark_read_write(page);
-
- zone->num_allocations++;
- zone->size_in_use += size;
- zone->max_size_in_use = MAX(zone->size_in_use, zone->max_size_in_use);
-
- vm_address_t addr = page + offset;
- log_zone_state(zone, "allocated", addr);
-
- return addr;
-}
-
-static void
-deallocate(pguard_zone_t *zone, vm_address_t addr)
-{
- slot_lookup_t res = lookup_slot(zone, addr);
- if (!res.live_block_addr) {
- // TODO(yln): error report; TODO(yln): distinguish between most likely cause
- // corrupted pointer (unused, *) or (*, !block_ptr) and double free (freed, block_ptr)
- MALLOC_REPORT_FATAL_ERROR(addr, "PGuard: invalid pointer passed to free");
- }
-
- uint32_t slot = res.slot;
- uint32_t metadata = zone->slots[slot].metadata;
-
- zone->slots[slot].state = ss_freed;
- capture_trace(&zone->metadata[metadata].dealloc_trace);
-
- vm_address_t page = page_addr(zone, slot);
- mark_inaccessible(page);
-
- zone->num_allocations--;
- zone->size_in_use -= zone->slots[slot].size;
-
- log_zone_state(zone, "freed", addr);
-}
-
-#define DELEGATE(function, args...) \
- zone->wrapped_zone->function(zone->wrapped_zone, args)
-
-static vm_address_t
-reallocate(pguard_zone_t *zone, vm_address_t addr, size_t new_size, boolean_t sample)
-{
- boolean_t guarded = is_guarded(zone, addr);
- // Note: should_sample() is stateful.
- MALLOC_ASSERT(guarded || sample);
-
- size_t size;
- if (guarded) {
- size = lookup_size(zone, addr);
- } else {
- size = DELEGATE(size, (void *)addr);
- }
- if (!size) {
- // TODO(yln): error report
- MALLOC_REPORT_FATAL_ERROR(addr, "PGuard: invalid pointer passed to realloc");
- }
-
- vm_address_t new_addr;
- if (sample && !is_full(zone)) {
- new_addr = allocate(zone, new_size, k_min_alignment);
- MALLOC_ASSERT(new_addr);
- } else {
- new_addr = (vm_address_t)DELEGATE(malloc, new_size);
- if (!new_addr) {
- return (vm_address_t)NULL;
- }
- }
- memcpy((void *)new_addr, (void *)addr, MIN(size, new_size));
-
- if (guarded) {
- deallocate(zone, addr);
- } else {
- DELEGATE(free, (void *)addr);
- }
- return new_addr;
-}
-
-
-#pragma mark -
-#pragma mark Lock Helpers
-
-static void init_lock(pguard_zone_t *zone) { _malloc_lock_init(&zone->lock); }
-static void lock(pguard_zone_t *zone) { _malloc_lock_lock(&zone->lock); }
-static void unlock(pguard_zone_t *zone) { _malloc_lock_unlock(&zone->lock); }
-static boolean_t trylock(pguard_zone_t *zone) { return _malloc_lock_trylock(&zone->lock); }
-
-
-#pragma mark -
-#pragma mark Zone Functions
-
-#define DELEGATE_UNSAMPLED(size, function, args...) \
- if (os_likely(!should_sample(zone, size))) \
- return DELEGATE(function, args)
-
-#define DELEGATE_UNGUARDED(ptr, function, args...) \
- if (os_likely(!is_guarded(zone, (vm_address_t)ptr))) \
- return DELEGATE(function, args)
-
-#define SAMPLED_ALLOCATE(size, alignment, function, args...) \
- DELEGATE_UNSAMPLED(size, function, args); \
- lock(zone); \
- void *ptr = (void *)allocate(zone, size, alignment); \
- unlock(zone); \
- if (!ptr) return DELEGATE(function, args)
-
-#define GUARDED_DEALLOCATE(ptr, function, args...) \
- DELEGATE_UNGUARDED(ptr, function, args); \
- lock(zone); \
- deallocate(zone, (vm_address_t)ptr); \
- unlock(zone)
-
-
-static size_t
-pguard_size(pguard_zone_t *zone, const void *ptr)
-{
- DELEGATE_UNGUARDED(ptr, size, ptr);
- lock(zone);
- size_t size = lookup_size(zone, (vm_address_t)ptr);
- unlock(zone);
- return size;
-}
-
-static void *
-pguard_malloc(pguard_zone_t *zone, size_t size)
-{
- SAMPLED_ALLOCATE(size, k_min_alignment, malloc, size);
- return ptr;
-}
-
-static void *
-pguard_calloc(pguard_zone_t *zone, size_t num_items, size_t size)
-{
- size_t total_size;
- if (os_unlikely(os_mul_overflow(num_items, size, &total_size))) {
- return DELEGATE(calloc, num_items, size);
- }
- SAMPLED_ALLOCATE(total_size, k_min_alignment, calloc, num_items, size);
- memset(ptr, 0, total_size);
- return ptr;
-}
-
-static void *
-pguard_valloc(pguard_zone_t *zone, size_t size)
-{
- SAMPLED_ALLOCATE(size, /*alignment=*/PAGE_SIZE, valloc, size);
- return ptr;
-}
-
-static void
-pguard_free(pguard_zone_t *zone, void *ptr)
-{
- GUARDED_DEALLOCATE(ptr, free, ptr);
-}
-
-static void *
-pguard_realloc(pguard_zone_t *zone, void *ptr, size_t new_size)
-{
- if (os_unlikely(!ptr)) {
- return pguard_malloc(zone, new_size);
- }
- boolean_t sample = should_sample(zone, new_size);
- if (os_likely(!sample)) {
- DELEGATE_UNGUARDED(ptr, realloc, ptr, new_size);
- }
- lock(zone);
- void *new_ptr = (void *)reallocate(zone, (vm_address_t)ptr, new_size, sample);
- unlock(zone);
- return new_ptr;
-}
-
-static void my_vm_deallocate(vm_address_t addr, size_t size);
-static void
-pguard_destroy(pguard_zone_t *zone)
-{
- DELEGATE(free, zone->metadata);
- DELEGATE(free, zone->slots);
- my_vm_deallocate(zone->begin, zone->size);
- my_vm_deallocate((vm_address_t)zone, sizeof(pguard_zone_t));
-}
-
-static unsigned
-pguard_batch_malloc(pguard_zone_t *zone, size_t size, void **results, unsigned count)
-{
- if (os_unlikely(count == 0)) {
- return 0;
- }
- DELEGATE_UNSAMPLED(size, batch_malloc, size, results, count);
-
- uint32_t sample_count = 1; // Sample at least one allocation.
- for (uint32_t i = 1; i < count; i++) {
- if (should_sample_counter(zone->sample_counter_range)) {
- sample_count++;
- }
- }
- // TODO(yln): Express the above with only one call to rand_uniform(). "n choose k"?
-
- for (uint32_t i = 0; i < sample_count; i++) {
- lock(zone);
- void *ptr = (void *)allocate(zone, size, k_min_alignment);
- unlock(zone);
- if (!ptr) {
- sample_count = i;
- break; // Zone full.
- }
- results[i] = ptr;
- }
-
- void **remaining_results = results + sample_count;
- uint32_t remaining_count = count - sample_count;
- remaining_count = DELEGATE(batch_malloc, size, remaining_results, remaining_count) ;
-
- // TODO(yln): sampled allocations will always be in the beginning of the results
- // array. We could shuffle it: https://en.wikipedia.org/wiki/Fisher–Yates_shuffle
- return sample_count + remaining_count;
-}
-
-static void
-pguard_batch_free(pguard_zone_t *zone, void **to_be_freed, unsigned count)
-{
- for (uint32_t i = 0; i < count; i++) {
- vm_address_t addr = (vm_address_t)to_be_freed[i];
- if (os_unlikely(is_guarded(zone, addr))) {
- lock(zone);
- deallocate(zone, addr);
- unlock(zone);
- to_be_freed[i] = NULL;
- }
- }
- return DELEGATE(batch_free, to_be_freed, count);
-}
-
-static void *
-pguard_memalign(pguard_zone_t *zone, size_t alignment, size_t size)
-{
- // Delegate for (alignment > page size) and invalid alignment sizes.
- if (alignment > PAGE_SIZE || !is_power_of_2(alignment) || alignment < sizeof(void *)) {
- return DELEGATE(memalign, alignment, size);
- }
- size_t adj_alignment = MAX(alignment, k_min_alignment);
- SAMPLED_ALLOCATE(size, adj_alignment, memalign, alignment, size);
- return ptr;
-}
-
-static void
-pguard_free_definite_size(pguard_zone_t *zone, void *ptr, size_t size)
-{
- GUARDED_DEALLOCATE(ptr, free_definite_size, ptr, size);
-}
-
-static size_t
-pguard_pressure_relief(pguard_zone_t *zone, size_t goal)
-{
- // We consume a constant amount of memory, so just delegate.
- return DELEGATE(pressure_relief, goal);
-}
-
-static boolean_t
-pguard_claimed_address(pguard_zone_t *zone, void *ptr)
-{
- DELEGATE_UNGUARDED(ptr, claimed_address, ptr);
- return TRUE;
-}
-
-
-#pragma mark -
-#pragma mark Introspection Functions
-
-typedef enum { rt_zone_only, rt_slots, rt_slots_and_metadata } read_type_t;
-
-#define READ(remote_address, size, local_memory) \
-{ \
- kern_return_t kr = reader(task, (vm_address_t)remote_address, size, (void **)local_memory); \
- if (kr != KERN_SUCCESS) return kr; \
-}
-
-static kern_return_t
-read_zone(task_t task, vm_address_t zone_address, memory_reader_t reader, pguard_zone_t *zone, read_type_t read_type)
-{
- pguard_zone_t *zone_ptr;
- READ(zone_address, sizeof(pguard_zone_t), &zone_ptr);
- *zone = *zone_ptr; // Copy to writable memory
- // Leaks zone_ptr if called from CrashReporter (crash_reporter_memory_reader_t allocates new buffers)
-
- if (read_type >= rt_slots) {
- READ(zone->slots, zone->num_slots * sizeof(slot_t), &zone->slots);
- }
- if (read_type >= rt_slots_and_metadata) {
- READ(zone->metadata, zone->max_metadata * sizeof(metadata_t), &zone->metadata);
- }
- return KERN_SUCCESS;
-}
-
-#define READ_ZONE(zone, read_type) \
- pguard_zone_t zone_copy; \
- { \
- kern_return_t kr = read_zone(task, zone_address, reader, &zone_copy, read_type); \
- if (kr != KERN_SUCCESS) return kr; \
- } \
- pguard_zone_t *zone = &zone_copy;
-
-#define RECORD(remote_address, size_, type) \
-{ \
- vm_range_t range = { .address = remote_address, .size = size_ }; \
- recorder(task, context, type, &range, /*count=*/1); \
-}
-
-static kern_return_t
-pguard_enumerator(task_t task, void *context, unsigned type_mask,
- vm_address_t zone_address, memory_reader_t reader,
- vm_range_recorder_t recorder)
-{
- MALLOC_ASSERT(reader);
- MALLOC_ASSERT(recorder);
-
- boolean_t record_allocs = (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE);
- boolean_t record_regions = (type_mask & MALLOC_PTR_REGION_RANGE_TYPE);
- if (!record_allocs && !record_regions) {
- return KERN_SUCCESS;
- }
-
- READ_ZONE(zone, rt_slots);
-
- for (uint32_t i = 0; i < zone->num_slots; i++) {
- if (zone->slots[i].state != ss_allocated) {
- continue;
- }
- // TODO(yln): we could do these in bulk. Currently, it shouldn't matter
- // since the number of active slots (bounded by max_allocations) is small.
- // If we optimize our allocator (to prevent wasting a page per allocation)
- // and this allows us to significantly grow the number of allocations, then
- // we should change the code here to record in chunks.
- if (record_regions) {
- vm_address_t page = page_addr(zone, i);
- RECORD(page, PAGE_SIZE, MALLOC_PTR_REGION_RANGE_TYPE);
- }
- if (record_allocs) {
- vm_address_t alloc = block_addr(zone, i);
- RECORD(alloc, zone->slots[i].size, MALLOC_PTR_IN_USE_RANGE_TYPE);
- }
- }
- return KERN_SUCCESS;
-}
-
-static void
-pguard_statistics(pguard_zone_t *zone, malloc_statistics_t *stats)
-{
- *stats = (malloc_statistics_t){
- .blocks_in_use = zone->num_allocations,
- .size_in_use = zone->size_in_use,
- .max_size_in_use = zone->max_size_in_use,
- .size_allocated = zone->num_allocations * PAGE_SIZE
- };
-}
-
-static kern_return_t
-pguard_statistics_task(task_t task, vm_address_t zone_address, memory_reader_t reader, malloc_statistics_t *stats)
-{
- READ_ZONE(zone, rt_zone_only);
- pguard_statistics(zone, stats);
- return KERN_SUCCESS;
-}
-
-static void
-print_zone(pguard_zone_t *zone, boolean_t verbose, print_task_printer_t printer) {
- malloc_statistics_t stats;
- pguard_statistics(zone, &stats);
- printer("PGuard zone: slots: %u, slots in use: %u, size in use: %llu, max size in use: %llu, allocated size: %llu\n",
- zone->num_slots, stats.blocks_in_use, stats.size_in_use, stats.max_size_in_use, stats.size_allocated);
- printer("Quarantine: size: %llu, address range: [%p - %p]\n", zone->size, zone->begin, zone->end);
-
- printer("Slots (#, state, offset, size, block address):\n");
- for (uint32_t i = 0; i < zone->num_slots; i++) {
- slot_state_t state = zone->slots[i].state;
- if (state != ss_allocated && !verbose) {
- continue;
- }
- const char *label = slot_state_labels[state];
- uint16_t offset = zone->slots[i].offset;
- uint16_t size = zone->slots[i].size;
- vm_address_t block = block_addr(zone, i);
- printer("%4u, %9s, %4u, %4u, %p\n", i, label, offset, size, block);
- }
-}
-
-
-static void
-pguard_print(pguard_zone_t *zone, boolean_t verbose)
-{
- print_zone(zone, verbose, malloc_report_simple);
-}
-
-static void
-pguard_print_task(task_t task, unsigned level, vm_address_t zone_address, memory_reader_t reader, print_task_printer_t printer)
-{
- pguard_zone_t zone;
- kern_return_t kr = read_zone(task, zone_address, reader, &zone, rt_slots);
- if (kr != KERN_SUCCESS) {
- printer("Failed to read PGuard zone at %p\n", zone_address);
- return;
- }
-
- boolean_t verbose = (level >= MALLOC_VERBOSE_PRINT_LEVEL);
- print_zone(&zone, verbose, printer);
-}
-
-static void
-pguard_log(pguard_zone_t *zone, void *address)
-{
- // Unsupported.
-}
-
-static size_t
-pguard_good_size(pguard_zone_t *zone, size_t size)
-{
- return DELEGATE(introspect->good_size, size);
-}
-
-static boolean_t
-pguard_check(pguard_zone_t *zone)
-{
- return TRUE; // Zone is always in a consistent state.
-}
-
-static void
-pguard_force_lock(pguard_zone_t *zone)
-{
- lock(zone);
-}
-
-static void
-pguard_force_unlock(pguard_zone_t *zone)
-{
- unlock(zone);
-}
-
-static void
-pguard_reinit_lock(pguard_zone_t *zone)
-{
- init_lock(zone);
-}
-
-static boolean_t
-pguard_zone_locked(pguard_zone_t *zone)
-{
- boolean_t lock_taken = trylock(zone);
- if (lock_taken) {
- unlock(zone);
- }
- return !lock_taken;
-}
-
-
-#pragma mark -
-#pragma mark Zone Templates
-
-// Suppress warning: incompatible function pointer types
-#define FN_PTR(fn) (void *)(&fn)
-
-static const malloc_introspection_t introspection_template = {
- // Block and region enumeration
- .enumerator = FN_PTR(pguard_enumerator),
-
- // Statistics
- .statistics = FN_PTR(pguard_statistics),
- .task_statistics = FN_PTR(pguard_statistics_task),
-
- // Logging
- .print = FN_PTR(pguard_print),
- .print_task = FN_PTR(pguard_print_task),
- .log = FN_PTR(pguard_log),
-
- // Queries
- .good_size = FN_PTR(pguard_good_size),
- .check = FN_PTR(pguard_check),
-
- // Locking
- .force_lock = FN_PTR(pguard_force_lock),
- .force_unlock = FN_PTR(pguard_force_unlock),
- .reinit_lock = FN_PTR(pguard_reinit_lock),
- .zone_locked = FN_PTR(pguard_zone_locked),
-
- // Discharge checking
- .enable_discharge_checking = NULL,
- .disable_discharge_checking = NULL,
- .discharge = NULL,
-#ifdef __BLOCKS__
- .enumerate_discharged_pointers = NULL,
-#else
- .enumerate_unavailable_without_blocks = NULL,
-#endif
-};
-
-static const malloc_zone_t malloc_zone_template = {
- // Reserved for CFAllocator
- .reserved1 = NULL,
- .reserved2 = NULL,
-
- // Standard operations
- .size = FN_PTR(pguard_size),
- .malloc = FN_PTR(pguard_malloc),
- .calloc = FN_PTR(pguard_calloc),
- .valloc = FN_PTR(pguard_valloc),
- .free = FN_PTR(pguard_free),
- .realloc = FN_PTR(pguard_realloc),
- .destroy = FN_PTR(pguard_destroy),
-
- // Batch operations
- .batch_malloc = FN_PTR(pguard_batch_malloc),
- .batch_free = FN_PTR(pguard_batch_free),
-
- // Introspection
- .zone_name = NULL, // Do not initialize with static string; set_zone_name() frees this pointer.
- .version = 12,
- .introspect = (malloc_introspection_t *)&introspection_template, // Effectively const.
-
- // Specialized operations
- .memalign = FN_PTR(pguard_memalign),
- .free_definite_size = FN_PTR(pguard_free_definite_size),
- .pressure_relief = FN_PTR(pguard_pressure_relief),
- .claimed_address = FN_PTR(pguard_claimed_address)
-};
-
-
-#pragma mark -
-#pragma mark Configuration Options
-
-static const char *
-env_var(const char *name)
-{
- const char **env = (const char **)*_NSGetEnviron();
- return _simple_getenv(env, name);
-}
-
-static uint32_t
-env_uint(const char *name, uint32_t default_value) {
- const char *value = env_var(name);
- if (!value) return default_value;
- return (uint32_t)strtoul(value, NULL, 0);
-}
-
-static boolean_t
-env_bool(const char *name) {
- const char *value = env_var(name);
- if (!value) return FALSE;
- return value[0] == '1';
-}
-
-#if CONFIG_FEATUREFLAGS_SIMPLE
-# define FEATURE_FLAG(feature, default) os_feature_enabled_simple(libmalloc, feature, default)
-#else
-# define FEATURE_FLAG(feature, default) (default)
-#endif
-
-
-#pragma mark -
-#pragma mark Zone Configuration
-
-static bool
-is_platform_binary(void)
-{
- uint32_t flags = 0;
- int err = csops(getpid(), CS_OPS_STATUS, &flags, sizeof(flags));
- if (err) {
- return false;
- }
- return (flags & CS_PLATFORM_BINARY);
-}
-
-static bool
-should_activate(bool internal_build)
-{
- uint32_t activation_rate = (internal_build ? 250 : 1000);
- return rand_uniform(activation_rate) == 0;
-}
-
-bool
-pguard_enabled(bool internal_build)
-{
- if (env_var("MallocProbGuard")) {
- return env_bool("MallocProbGuard");
- }
-#if TARGET_OS_OSX || TARGET_OS_IOS
- if (FEATURE_FLAG(ProbGuard, true) && (internal_build || is_platform_binary())) {
- bool activate = TARGET_OS_OSX ?
- should_activate(internal_build) :
- env_bool("MallocProbGuardViaLaunchd");
- if (activate) {
- return true;
- }
- }
-#endif // macOS || iOS
- if (FEATURE_FLAG(ProbGuardAllProcesses, false)) {
- return true;
- }
- return false;
-}
-
-static uint32_t
-choose_memory_budget_in_kb(void)
-{
- return (TARGET_OS_OSX ? 8 : 2) * 1024;
-}
-
-// TODO(yln): uniform sampling is likely not optimal here, since we will tend to
-// sample around the average of our range, which is probably more frequent than
-// what we want. We probably want the average to be less frequent, but still be
-// able to reach the "very frequent" end of our range occassionally. Consider
-// using a geometric (or other weighted distribution) here.
-static uint32_t
-choose_sample_rate(void)
-{
- uint32_t min = 500, max = 10000;
- return rand_uniform(max - min) + min;
-}
-
-static const double k_slot_multiplier = 10.0;
-static const double k_metadata_multiplier = 3.0;
-static uint32_t
-compute_max_allocations(size_t memory_budget_in_kb)
-{
- size_t memory_budget = memory_budget_in_kb * 1024;
- size_t fixed_overhead = round_page(sizeof(pguard_zone_t));
- size_t vm_map_entry_size = 80; // struct vm_map_entry in <vm/vm_map.h>
- size_t per_allocation_overhead =
- PAGE_SIZE +
- k_slot_multiplier * 2 * vm_map_entry_size + // TODO(yln): Implement mark_inaccessible to fill holes so we can drop the k_slot_multiplier here. +27% more protected allocations!
- // 2 * vm_map_entry_size + // Allocations split the VM region
- k_slot_multiplier * sizeof(slot_t) +
- k_metadata_multiplier * sizeof(metadata_t);
-
- uint32_t max_allocations = (uint32_t)((memory_budget - fixed_overhead) / per_allocation_overhead);
- if (memory_budget < fixed_overhead || max_allocations == 0) {
- MALLOC_REPORT_FATAL_ERROR(0, "PGuard: memory budget too small");
- }
- return max_allocations;
-}
-
-static void
-configure_zone(pguard_zone_t *zone) {
- uint32_t memory_budget_in_kb = env_uint("MallocPGuardMemoryBudgetInKB", choose_memory_budget_in_kb());
- zone->max_allocations = env_uint("MallocPGuardAllocations", compute_max_allocations(memory_budget_in_kb));
- zone->num_slots = env_uint("MallocPGuardSlots", k_slot_multiplier * zone->max_allocations);
- zone->max_metadata = env_uint("MallocPGuardMetadata", k_metadata_multiplier * zone->max_allocations);
- uint32_t sample_rate = env_uint("MallocPGuardSampleRate", choose_sample_rate());
- if (sample_rate == 0) {
- MALLOC_REPORT_FATAL_ERROR(0, "PGuard: sample rate cannot be 0");
- }
- // Approximate a (1 / sample_rate) chance for sampling; 1 means "always sample".
- zone->sample_counter_range = (sample_rate != 1) ? (2 * sample_rate) : 1;
- zone->signal_handler = env_bool("MallocPGuardSignalHandler");
- zone->debug_log = env_bool("MallocPGuardDebugLog");
- zone->debug_log_throttle_ms = env_uint("MallocPGuardDebugLogThrottleInMillis", 1000);
-
- if (zone->debug_log) {
- malloc_report(ASL_LEVEL_INFO,
- "PGuard: configuration: %u allocations, %u slots, %u metadata, 1/%u sample rate\n",
- zone->max_allocations, zone->num_slots, zone->max_metadata, sample_rate);
- }
-}
-
-
-#pragma mark -
-#pragma mark Zone Creation
-
-#define VM_PROT_READ_WRITE (VM_PROT_READ | VM_PROT_WRITE)
-
-static vm_address_t my_vm_map(size_t size, vm_prot_t protection, int tag);
-static void my_vm_deallocate(vm_address_t addr, size_t size);
-static void my_vm_protect(vm_address_t addr, size_t size, vm_prot_t protection);
-
-static void
-setup_zone(pguard_zone_t *zone, malloc_zone_t *wrapped_zone) {
- // Malloc zone
- zone->malloc_zone = malloc_zone_template;
- zone->wrapped_zone = wrapped_zone;
-
- // Configuration
- configure_zone(zone);
-
- // Quarantine
- zone->size = quarantine_size(zone->num_slots);
- zone->begin = my_vm_map(zone->size, VM_PROT_NONE, VM_MEMORY_MALLOC_PGUARD); // TODO(yln): place at "unusually high" address to minimize chance that a randomly corrupted pointers fall into the guarded range.
- zone->end = zone->begin + zone->size;
-
- // Metadata
- zone->slots = DELEGATE(malloc, zone->num_slots * sizeof(slot_t));
- zone->metadata = DELEGATE(malloc, zone->max_metadata * sizeof(metadata_t));
- MALLOC_ASSERT(zone->slots && zone->metadata);
-
- // Mutable state
- init_lock(zone);
-}
-
-static void install_signal_handler(void *unused);
-malloc_zone_t *
-pguard_create_zone(malloc_zone_t *wrapped_zone)
-{
- pguard_zone_t *zone = (pguard_zone_t *)my_vm_map(sizeof(pguard_zone_t), VM_PROT_READ_WRITE, VM_MEMORY_MALLOC);
- setup_zone(zone, wrapped_zone);
- my_vm_protect((vm_address_t)zone, PAGE_MAX_SIZE, VM_PROT_READ);
-
- if (zone->signal_handler) {
- static os_once_t once_pred;
- os_once(&once_pred, NULL, &install_signal_handler);
- }
-
- return (malloc_zone_t *)zone;
-}
-
-#pragma mark -
-#pragma mark Logging
-
-static uint64_t
-to_millis(uint64_t mach_ticks)
-{
- mach_timebase_info_data_t timebase;
- mach_timebase_info(&timebase);
- const uint64_t nanos_per_ms = 1e6;
- return (mach_ticks * timebase.numer / timebase.denom) / nanos_per_ms;
-}
-
-static boolean_t
-should_log(pguard_zone_t *zone)
-{
- if (!zone->debug_log) {
- return FALSE;
- }
- uint64_t now = mach_absolute_time();
- uint64_t delta_ms = to_millis(now - zone->last_log_time);
- boolean_t log = (delta_ms >= zone->debug_log_throttle_ms);
- if (log) {
- zone->last_log_time = now;
- }
- return log;
-}
-
-static void
-log_zone_state(pguard_zone_t *zone, const char *type, vm_address_t addr)
-{
- if (!should_log(zone)) {
- return;
- }
- malloc_report(ASL_LEVEL_INFO, "PGuard: %9s 0x%lx, fill state: %3u/%u\n",
- type, addr, zone->num_allocations, zone->max_allocations);
-}
-
-
-#pragma mark -
-#pragma mark Fault Diagnosis
-
-static void
-fill_in_report(pguard_zone_t *zone, uint32_t slot, pguard_report_t *report)
-{
- slot_t *s = &zone->slots[slot];
- metadata_t *m = &zone->metadata[s->metadata];
-
- report->nearest_allocation = block_addr(zone, slot);
- report->allocation_size = s->size;
- report->allocation_state = slot_state_labels[s->state];
- report->num_traces = 0;
-
- if (m->slot == slot) {
- report->num_traces++;
- memcpy(&report->alloc_trace, &m->alloc_trace, sizeof(stack_trace_t));
- if (s->state == ss_freed) {
- report->num_traces++;
- memcpy(&report->dealloc_trace, &m->dealloc_trace, sizeof(stack_trace_t));
- }
- }
-}
-
-static void
-diagnose_page_fault(pguard_zone_t *zone, vm_address_t fault_address, pguard_report_t *report)
-{
- slot_lookup_t res = lookup_slot(zone, fault_address);
- slot_state_t ss = zone->slots[res.slot].state;
-
- // We got here because of a page fault.
- MALLOC_ASSERT(ss != ss_allocated || res.bounds == b_oob_guard_page);
-
- // Note that all of the following error conditions may also be caused by:
- // *) Randomly corrupted pointer
- // *) Long-range OOB (access stride > (page size / 2))
- // We will always misdiagnose some of these errors no matter how we slice it.
-
- // TODO(yln): extract "nearest allocation helper"
- switch (ss) {
- case ss_unused:
- // Nearest slot was never used.
- // TODO(yln): if bounds == oob_guard_page; we could try to look at the slot on the other side of the guard page.
- report->error_type = "long-range OOB";
- report->confidence = "low";
- break;
- case ss_allocated:
- // Most likely an OOB access from an active allocation onto a guard page.
- MALLOC_ASSERT(res.bounds == b_oob_guard_page);
- report->error_type = "out-of-bounds";
- report->confidence = "high";
- break;
- case ss_freed:
- if (res.bounds == b_block_addr || res.bounds == b_valid) {
- report->error_type = "use-after-free";
- report->confidence = "high";
- } else {
- MALLOC_ASSERT(res.bounds == b_oob_slot || res.bounds == b_oob_guard_page);
- // This could be a combination of OOB and UAF, or one of the generic errors
- // outlined above.
- // TODO(yln): still try to diagnose something here
- report->error_type = "OOB + UAF";
- report->confidence = "low";
- }
- break;
- default:
- __builtin_unreachable();
- }
-
- report->fault_address = fault_address;
- fill_in_report(zone, res.slot, report);
-}
-
-
-#pragma mark -
-#pragma mark Error Printing
-
-static const uint32_t k_buf_len = 1024;
-static void
-get_symbol_and_module_name(vm_address_t addr, char buf[k_buf_len])
-{
-#if !TARGET_OS_DRIVERKIT
- Dl_info info;
- int success = dladdr((void *)addr, &info);
- MALLOC_ASSERT(success);
- snprintf(buf, k_buf_len, "%s (%s)", info.dli_sname, info.dli_fname);
-#else
- strcpy(buf, "?");
-#endif
-}
-
-static void
-print_trace(stack_trace_t *trace, const char *label)
-{
- malloc_report(ASL_LEVEL_ERR, "%s trace (thread %llu):\n", label, trace->thread_id);
- for (uint32_t i = 0; i < trace->num_frames; i++) {
- char sym_name[k_buf_len];
- get_symbol_and_module_name(trace->frames[i], sym_name);
- malloc_report(ASL_LEVEL_ERR, " #%u %s\n", i, sym_name);
- }
- malloc_report(ASL_LEVEL_ERR, "\n", label);
-}
-
-static void
-print_report(pguard_report_t *report)
-{
- malloc_report(ASL_LEVEL_ERR, "PGuard: invalid access at 0x%lx\n",
- report->fault_address);
- malloc_report(ASL_LEVEL_ERR, "Error type: %s (%s confidence)\n",
- report->error_type, report->confidence);
- malloc_report(ASL_LEVEL_ERR, "Nearest allocation: 0x%lx, size: %lu, state: %s\n",
- report->nearest_allocation, report->allocation_size, report->allocation_state);
-
- if (report->num_traces >= 1) {
- print_trace(&report->alloc_trace, "Allocation");
- if (report->num_traces >= 2) {
- print_trace(&report->dealloc_trace, "Deallocation");
- }
- } else {
- malloc_report(ASL_LEVEL_ERR, "Allocation stack traces not available. "
- "Try increasing `MallocPGuardMetadata` and rerun.\n");
- }
-}
-
-
-#pragma mark -
-#pragma mark Crash Reporter API
-
-static crash_reporter_memory_reader_t g_crm_reader;
-static kern_return_t
-memory_reader_adapter(task_t task, vm_address_t address, vm_size_t size, void **local_memory)
-{
- *local_memory = g_crm_reader(task, address, size);
- return *local_memory ? KERN_SUCCESS : KERN_FAILURE;
-}
-
-kern_return_t
-pgm_diagnose_fault_from_crash_reporter(vm_address_t fault_address, pgm_report_t *report,
- task_t task, vm_address_t zone_address, crash_reporter_memory_reader_t crm_reader)
-{
- g_crm_reader = crm_reader;
-
- memory_reader_t *reader = memory_reader_adapter;
- READ_ZONE(zone, rt_slots_and_metadata);
-
- diagnose_page_fault(zone, fault_address, report);
- free(zone->metadata);
- free(zone->slots);
- // zone lives on the stack
-
- return KERN_SUCCESS;
-}
-
-
-#pragma mark -
-#pragma mark Signal Handler
-
-extern malloc_zone_t **malloc_zones;
-static void
-report_error_from_signal_handler(vm_address_t fault_address)
-{
- // TODO(yln): maybe look up by name, once the zone naming has been figured out.
- pguard_zone_t *zone = (pguard_zone_t *)malloc_zones[0];
- MALLOC_ASSERT(zone->malloc_zone.size == FN_PTR(pguard_size));
-
- if (!is_guarded(zone, fault_address)) {
- return;
- }
-
- pguard_report_t report;
- {
- trylock(zone); // Best-effort locking to avoid deadlock.
- diagnose_page_fault(zone, fault_address, &report);
- unlock(zone);
- }
- print_report(&report);
-
- MALLOC_REPORT_FATAL_ERROR(fault_address, "PGuard: invalid access detected");
-}
-
-static struct sigaction prev_sigaction;
-static void
-signal_handler(int sig, siginfo_t *info, void *ucontext)
-{
- MALLOC_ASSERT(sig == SIGBUS);
- report_error_from_signal_handler((vm_address_t)info->si_addr);
-
- // Delegate to previous handler.
- if (prev_sigaction.sa_flags & SA_SIGINFO) {
- prev_sigaction.sa_sigaction(sig, info, ucontext);
- } else if (prev_sigaction.sa_handler == SIG_IGN ||
- prev_sigaction.sa_handler == SIG_DFL) {
- // If the previous handler was the default handler, or was ignoring this
- // signal, install the default handler and re-raise the signal in order to
- // get a core dump and terminate this process.
- signal(SIGBUS, SIG_DFL);
- raise(SIGBUS);
- } else {
- prev_sigaction.sa_handler(sig);
- }
-}
-
-static void
-install_signal_handler(void *unused)
-{
- struct sigaction act = {
- .sa_sigaction = &signal_handler,
- .sa_flags = SA_SIGINFO
- };
- int res = sigaction(SIGBUS, &act, &prev_sigaction);
- MALLOC_ASSERT(res == 0);
-}
-
-
-#pragma mark -
-#pragma mark Mockable Helpers
-
-#ifndef PGUARD_MOCK_RANDOM
-static uint32_t
-rand_uniform(uint32_t upper_bound)
-{
- MALLOC_ASSERT(upper_bound > 0);
- return arc4random_uniform(upper_bound);
-}
-#endif
-
-#ifndef PGUARD_MOCK_CAPTURE_TRACE
-MALLOC_ALWAYS_INLINE
-static inline void
-capture_trace(stack_trace_t *trace)
-{
- // Frame 0 is thread_stack_pcs() itself; last frame usually is a garbage value.
- const uint32_t dropped_frames = 2;
- const uint32_t max_frames = k_pguard_trace_max_frames + dropped_frames;
- vm_address_t frames[max_frames];
- uint32_t num_frames;
- thread_stack_pcs(frames, max_frames, &num_frames);
- num_frames = (num_frames > dropped_frames) ? (num_frames - dropped_frames) : 0;
-
- trace->thread_id = _pthread_threadid_self_np_direct();
- trace->num_frames = num_frames;
- memcpy(trace->frames, &frames[1], num_frames * sizeof(vm_address_t));
-}
-#endif
-
-#ifndef PGUARD_MOCK_PAGE_ACCESS
-static void
-mark_inaccessible(vm_address_t page)
-{
- int res = madvise((void *)page, PAGE_SIZE, CONFIG_MADVISE_STYLE);
- MALLOC_ASSERT(res == 0);
- my_vm_protect(page, PAGE_SIZE, VM_PROT_NONE);
-}
-
-static void
-mark_read_write(vm_address_t page)
-{
- // It is faster to just unprotect the page without calling madvise() first.
- my_vm_protect(page, PAGE_SIZE, VM_PROT_READ_WRITE);
-}
-#endif
-
-
-#pragma mark -
-#pragma mark Mach VM Helpers
-
-static vm_address_t
-my_vm_map(size_t size, vm_prot_t protection, int tag)
-{
- vm_map_t target = mach_task_self();
- mach_vm_address_t address = 0;
- mach_vm_size_t size_rounded = round_page(size);
- mach_vm_offset_t mask = 0x0;
- int flags = VM_FLAGS_ANYWHERE | VM_MAKE_TAG(tag);
- mem_entry_name_port_t object = MEMORY_OBJECT_NULL;
- memory_object_offset_t offset = 0;
- boolean_t copy = FALSE;
- vm_prot_t cur_protection = protection;
- vm_prot_t max_protection = VM_PROT_READ | VM_PROT_WRITE;
- vm_inherit_t inheritance = VM_INHERIT_DEFAULT;
-
- kern_return_t kr = mach_vm_map(target, &address, size_rounded, mask, flags,
- object, offset, copy, cur_protection, max_protection, inheritance);
- MALLOC_ASSERT(kr == KERN_SUCCESS);
- return address;
-}
-
-static void
-my_vm_deallocate(vm_address_t addr, size_t size)
-{
- vm_map_t target = mach_task_self();
- mach_vm_address_t address = (mach_vm_address_t)addr;
- mach_vm_size_t size_rounded = round_page(size);
- kern_return_t kr = mach_vm_deallocate(target, address, size_rounded);
- MALLOC_ASSERT(kr == KERN_SUCCESS);
-}
-
-static void
-my_vm_protect(vm_address_t addr, size_t size, vm_prot_t protection) {
- vm_map_t target = mach_task_self();
- mach_vm_address_t address = (mach_vm_address_t)addr;
- mach_vm_size_t size_rounded = round_page(size);
- boolean_t set_maximum = FALSE;
- kern_return_t kr = mach_vm_protect(target, address, size_rounded, set_maximum, protection);
- MALLOC_ASSERT(kr == KERN_SUCCESS);
-}