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--- libmalloc/libmalloc-317.140.5/src/vm.c
+++ libmalloc/libmalloc-474.0.13/src/vm.c
@@ -24,12 +24,14 @@
#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
@@ -42,15 +44,15 @@
mvm_aslr_init(void)
{
// Prepare ASLR
-#if __i386__ || __x86_64__ || __arm64__ || (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR)
-#if __i386__
+#if defined(__i386__) || defined(__x86_64__) || defined(__arm64__) || TARGET_OS_DRIVERKIT || (TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR)
+#if defined(__i386__)
uintptr_t stackbase = 0x8fe00000;
int entropic_bits = 3;
-#elif __x86_64__
+#elif defined(__x86_64__)
uintptr_t stackbase = USRSTACK64;
int entropic_bits = 16;
-#elif __arm64__
-#if __LP64__
+#elif defined(__arm64__)
+#if defined(__LP64__)
uintptr_t stackbase = USRSTACK64;
int entropic_bits = 7;
#else // __LP64__
@@ -65,7 +67,32 @@
if (mvm_aslr_enabled()) {
if (0 == entropic_address) {
- uintptr_t t = stackbase - MAXSSIZ - ((uintptr_t)(malloc_entropy[1] & ((1 << entropic_bits) - 1)) << ENTROPIC_SHIFT);
+ 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_TINY))) {
+ // 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
+
OSAtomicCompareAndSwapLong(0, t, (volatile long *)&entropic_limit);
OSAtomicCompareAndSwapLong(0, t - ENTROPIC_KABILLION, (volatile long *)&entropic_address);
}
@@ -125,9 +152,11 @@
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
}
if (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);
+ 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);
+ }
return NULL;
}
addr = (uintptr_t)vm_addr;
@@ -140,7 +169,7 @@
// provided we don't wrap, deallocate and retry, in theexpanded
// entropic range
- if (u < t) {
+ if (u < t && u >= entropic_base) {
mach_vm_deallocate(mach_task_self(), vm_addr, allocation_size);
OSAtomicCompareAndSwapLong(t, u,
(volatile long *)&entropic_address); // Just one reduction please
@@ -152,7 +181,7 @@
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) {
+ if (u < t && u >= entropic_base) {
OSAtomicCompareAndSwapLong(t, u, (volatile long *)&entropic_address); // Just one reduction please
}
// fall through to use what we got
@@ -249,11 +278,11 @@
if (pgHi > pgLo) {
size_t len = pgHi - pgLo;
- if (scribble) {
+ if (scribble && malloc_zero_policy != MALLOC_ZERO_ON_FREE) {
memset((void *)pgLo, SCRUBBLE_BYTE, len); // Scribble on MADV_FREEd memory
}
-#if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
+#if MALLOC_TARGET_IOS
if (last) {
if (*last == pgLo) {
return 0;
@@ -261,7 +290,7 @@
*last = pgLo;
}
-#endif // TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
+#endif // MALLOC_TARGET_IOS
MAGMALLOC_MADVFREEREGION(rack, r, (void *)pgLo, (int)len); // DTrace USDT Probe
if (-1 == madvise((void *)pgLo, len, CONFIG_MADVISE_STYLE)) {
@@ -278,3 +307,57 @@
}
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