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--- libmalloc/libmalloc-409.60.6/src/vm.c
+++ libmalloc/libmalloc-317.40.8/src/vm.c
@@ -24,14 +24,12 @@
#include "internal.h"
static volatile uintptr_t entropic_address = 0;
-static volatile uintptr_t entropic_base = 0;
static volatile uintptr_t entropic_limit = 0;
MALLOC_NOEXPORT
uint64_t malloc_entropy[2] = {0, 0};
#define ENTROPIC_KABILLION 0x10000000 /* 256Mb */
-#define ENTROPIC_USER_RANGE_SIZE 0x200000000ULL /* 8Gb */
// <rdar://problem/22277891> align 64bit ARM shift to 32MB PTE entries
#if MALLOC_TARGET_IOS && MALLOC_TARGET_64BIT
@@ -44,7 +42,7 @@
mvm_aslr_init(void)
{
// Prepare ASLR
-#if __i386__ || __x86_64__ || __arm64__ || TARGET_OS_DRIVERKIT || (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR)
+#if __i386__ || __x86_64__ || __arm64__ || (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR)
#if __i386__
uintptr_t stackbase = 0x8fe00000;
int entropic_bits = 3;
@@ -67,32 +65,7 @@
if (mvm_aslr_enabled()) {
if (0 == entropic_address) {
- uintptr_t t = stackbase - MAXSSIZ - ((uintptr_t)(malloc_entropy[1] &
- ((1 << entropic_bits) - 1)) << ENTROPIC_SHIFT);
-#if MALLOC_TARGET_IOS && MALLOC_TARGET_64BIT
- uintptr_t addr = 0;
-
- /* If kernel VM user ranges are enabled mach_vm_allocate/map will provide memory
- * in the upper VM address range. This range is randomized per process. For now
- * we do not have this metadata plumbed through so we make a single allocation
- * with the appropriate tag to determine where our heap is. If we are given an
- * allocation above where we expect then we can safely assume VM ranges are enabled.
- *
- * If so we do not need to apply further entropy but do need to ensure
- * we mask off the address to a PTE boundary.
- */
- if (KERN_SUCCESS == mach_vm_allocate(mach_task_self(), (mach_vm_address_t *)&addr,
- vm_page_quanta_size, VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_MALLOC))) {
- // Fall through and use existing base if addr < stackbase
- if (addr > stackbase) {
- t = (addr + ENTROPIC_USER_RANGE_SIZE) & ~((1 << ENTROPIC_SHIFT) - 1);
- OSAtomicCompareAndSwapLong(0, addr, (volatile long *)&entropic_base);
- }
-
- mach_vm_deallocate(mach_task_self(), addr, vm_page_quanta_size);
- }
-#endif // MALLOC_TARGET_IOS && MALLOC_TARGET_64BIT
-
+ uintptr_t t = stackbase - MAXSSIZ - ((uintptr_t)(malloc_entropy[1] & ((1 << entropic_bits) - 1)) << ENTROPIC_SHIFT);
OSAtomicCompareAndSwapLong(0, t, (volatile long *)&entropic_limit);
OSAtomicCompareAndSwapLong(0, t - ENTROPIC_KABILLION, (volatile long *)&entropic_address);
}
@@ -152,11 +125,9 @@
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
}
if (kr) {
- if (kr != KERN_NO_SPACE) {
- malloc_zone_error(debug_flags, false, "can't allocate region\n:"
- "*** mach_vm_map(size=%lu, flags: %x) failed (error code=%d)\n",
- size, debug_flags, kr);
- }
+ malloc_zone_error(debug_flags, false, "can't allocate region\n:"
+ "*** mach_vm_map(size=%lu, flags: %x) failed (error code=%d)\n",
+ size, debug_flags, kr);
return NULL;
}
addr = (uintptr_t)vm_addr;
@@ -169,7 +140,7 @@
// provided we don't wrap, deallocate and retry, in theexpanded
// entropic range
- if (u < t && u >= entropic_base) {
+ if (u < t) {
mach_vm_deallocate(mach_task_self(), vm_addr, allocation_size);
OSAtomicCompareAndSwapLong(t, u,
(volatile long *)&entropic_address); // Just one reduction please
@@ -181,7 +152,7 @@
if (addr < entropic_address) { // we wrapped to find this allocation, expand the entropic range
uintptr_t t = entropic_address;
uintptr_t u = t - ENTROPIC_KABILLION;
- if (u < t && u >= entropic_base) {
+ if (u < t) {
OSAtomicCompareAndSwapLong(t, u, (volatile long *)&entropic_address); // Just one reduction please
}
// fall through to use what we got
@@ -278,11 +249,11 @@
if (pgHi > pgLo) {
size_t len = pgHi - pgLo;
- if (scribble && malloc_zero_policy != MALLOC_ZERO_ON_FREE) {
+ if (scribble) {
memset((void *)pgLo, SCRUBBLE_BYTE, len); // Scribble on MADV_FREEd memory
}
-#if MALLOC_TARGET_IOS
+#if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
if (last) {
if (*last == pgLo) {
return 0;
@@ -290,7 +261,7 @@
*last = pgLo;
}
-#endif // MALLOC_TARGET_IOS
+#endif // TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
MAGMALLOC_MADVFREEREGION(rack, r, (void *)pgLo, (int)len); // DTrace USDT Probe
if (-1 == madvise((void *)pgLo, len, CONFIG_MADVISE_STYLE)) {
@@ -307,57 +278,3 @@
}
return 0;
}
-
-#if CONFIG_DEFERRED_RECLAIM
-static struct mach_vm_reclaim_ringbuffer_v1_s reclaim_buffer;
-static _malloc_lock_s reclaim_buffer_lock = _MALLOC_LOCK_INIT;
-
-kern_return_t
-mvm_deferred_reclaim_init(void)
-{
- return mach_vm_reclaim_ringbuffer_init(&reclaim_buffer);
-}
-
-
-bool
-mvm_reclaim_mark_used(uint64_t id, mach_vm_address_t ptr, uint32_t size, unsigned int debug_flags)
-{
- bool used;
- if (debug_flags & MALLOC_ADD_GUARD_PAGE_FLAGS) {
- if (os_add_overflow(size, 2 * large_vm_page_quanta_size, &size)) {
- return false;
- }
- ptr -= large_vm_page_quanta_size;
- }
- _malloc_lock_lock(&reclaim_buffer_lock);
- used = mach_vm_reclaim_mark_used(&reclaim_buffer, id, ptr, size);
- _malloc_lock_unlock(&reclaim_buffer_lock);
- return used;
-}
-
-uint64_t
-mvm_reclaim_mark_free(vm_address_t ptr, uint32_t size, unsigned int debug_flags)
-{
- uint64_t id;
- bool should_update_kernel_accounting = false;
- if (debug_flags & MALLOC_ADD_GUARD_PAGE_FLAGS) {
- if (os_add_overflow(size, 2 * large_vm_page_quanta_size, &size)) {
- return VM_RECLAIM_INDEX_NULL;
- }
- ptr -= large_vm_page_quanta_size;
- }
- _malloc_lock_lock(&reclaim_buffer_lock);
- id = mach_vm_reclaim_mark_free(&reclaim_buffer, ptr, size, &should_update_kernel_accounting);
- _malloc_lock_unlock(&reclaim_buffer_lock);
- if (should_update_kernel_accounting) {
- mach_vm_reclaim_update_kernel_accounting(&reclaim_buffer);
- }
- return id;
-}
-
-bool
-mvm_reclaim_is_available(uint64_t id)
-{
- return mach_vm_reclaim_is_available(&reclaim_buffer, id);
-}
-#endif // CONFIG_DEFERRED_RECLAIM