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src/wrapper_zones.c /dev/null libmalloc-792.60.6
--- /dev/null
+++ libmalloc/libmalloc-792.60.6/src/wrapper_zones.c
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2023 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 "internal.h"
+
+
+// Retrieve PAC-stripped address of introspection struct.  We avoid
+// authenticating the pointer when loading it's value, because we can't
+// authenticate pointers copied from remote processes (or corpses).
+static vm_address_t
+get_introspection_addr(const malloc_zone_t *zone)
+{
+	// return zone->malloc_zone.introspect;  // but without ptrauth
+	vm_address_t ptr_addr =
+			(vm_address_t)zone + offsetof(malloc_zone_t, introspect);
+	vm_address_t addr = *(vm_address_t *)ptr_addr;
+	return (vm_address_t)ptrauth_strip((malloc_introspection_t *)addr,
+			ptrauth_key_process_independent_data);
+}
+
+kern_return_t
+get_zone_type(task_t task, memory_reader_t reader,
+		vm_address_t zone_address, unsigned *zone_type)
+{
+	MALLOC_ASSERT(reader);
+
+	kern_return_t kr;
+	*zone_type = MALLOC_ZONE_TYPE_UNKNOWN;
+
+	// malloc_introspection_t::zone_type requires zone version >= 14
+	malloc_zone_t *zone;
+	kr = reader(task, zone_address, sizeof(malloc_zone_t), (void **)&zone);
+	if (kr != KERN_SUCCESS) {
+		return kr;
+	}
+	if (zone->version < 14) {
+		return KERN_SUCCESS;
+	}
+
+	// Retrieve zone type
+	vm_address_t zone_type_addr = get_introspection_addr(zone) +
+			offsetof(malloc_introspection_t, zone_type);
+	unsigned *zt;
+	kr = reader(task, zone_type_addr, sizeof(unsigned), (void **)&zt);
+	if (kr != KERN_SUCCESS) {
+		return kr;
+	}
+
+	*zone_type = *zt;
+	return KERN_SUCCESS;
+}
+
+kern_return_t
+malloc_get_wrapped_zone(task_t task, memory_reader_t reader,
+		vm_address_t zone_address, vm_address_t *wrapped_zone_address)
+{
+	reader = reader_or_in_memory_fallback(reader, task);
+
+	kern_return_t kr;
+	*wrapped_zone_address = (vm_address_t)NULL;
+
+	unsigned zone_type;
+	kr = get_zone_type(task, reader, zone_address, &zone_type);
+	if (kr != KERN_SUCCESS) {
+		return kr;
+	}
+	if (zone_type != MALLOC_ZONE_TYPE_PGM &&
+			zone_type != MALLOC_ZONE_TYPE_SANITIZER) {
+		return KERN_SUCCESS;
+	}
+
+	// Load wrapped zone address
+	vm_address_t wrapped_zone_ptr_addr = zone_address + WRAPPED_ZONE_OFFSET;
+	vm_address_t *wrapped_zone_addr;
+	kr = reader(task, wrapped_zone_ptr_addr, sizeof(vm_address_t),
+			(void **)&wrapped_zone_addr);
+	if (kr != KERN_SUCCESS) {
+		return kr;
+	}
+
+	*wrapped_zone_address = *wrapped_zone_addr;
+	return KERN_SUCCESS;
+}
+
+// Internal, in-process helper for task-based SPI
+malloc_zone_t *
+get_wrapped_zone(malloc_zone_t *zone)
+{
+	malloc_zone_t *wrapped_zone;
+	kern_return_t kr = malloc_get_wrapped_zone(mach_task_self(),
+			/*memory_reader=*/NULL, (vm_address_t)zone, (vm_address_t *)&wrapped_zone);
+	MALLOC_ASSERT(kr == KERN_SUCCESS);  // In-process lookup cannot fail
+	return wrapped_zone;
+}