Update Mac memory code references

The Mac malloc interceptor relies on internals of macOS.
Update those internals and links to the 10.15 versions.

This relands 994f22b5
with a fix for profiling_client.cc which correctly only
includes a Mac file header on the Mac.

Bug: none
Change-Id: I8132dc1ffeeb0c6b65edb80cc729bcb4836f2121
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2377983Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#802429}

base/allocator/allocator_interception_mac.mm

@@ -77,13 +77,14 @@ void DeprotectMallocZone(ChromeMallocZone* default_zone,
   MACH_CHECK(result == KERN_SUCCESS, result) << "vm_region_64";
 
   // The kernel always returns a null object for VM_REGION_BASIC_INFO_64, but
-  // balance it with a deallocate in case this ever changes. See 10.9.2
-  // xnu-2422.90.20/osfmk/vm/vm_map.c vm_map_region.
+  // balance it with a deallocate in case this ever changes. See
+  // the VM_REGION_BASIC_INFO_64 case in vm_map_region() in 10.15's
+  // https://opensource.apple.com/source/xnu/xnu-6153.11.26/osfmk/vm/vm_map.c .
   mach_port_deallocate(mach_task_self(), unused);
 
   // Does the region fully enclose the zone pointers? Possibly unwarranted
-  // simplification used: using the size of a full version 8 malloc zone rather
-  // than the actual smaller size if the passed-in zone is not version 8.
+  // simplification used: using the size of a full version 10 malloc zone rather
+  // than the actual smaller size if the passed-in zone is not version 10.
   CHECK(*reprotection_start <= reinterpret_cast<vm_address_t>(default_zone));
   vm_size_t zone_offset = reinterpret_cast<vm_address_t>(default_zone) -
                           reinterpret_cast<vm_address_t>(*reprotection_start);
@@ -147,8 +148,8 @@ void* oom_killer_memalign(struct _malloc_zone_t* zone,
                           size_t size) {
   void* result = g_old_zone.memalign(zone, alignment, size);
   // Only die if posix_memalign would have returned ENOMEM, since there are
-  // other reasons why NULL might be returned (see
-  // http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c ).
+  // other reasons why null might be returned. See posix_memalign() in 10.15's
+  // https://opensource.apple.com/source/libmalloc/libmalloc-283/src/malloc.c .
   if (!result && size && alignment >= sizeof(void*) &&
       base::bits::IsPowerOfTwo(alignment)) {
     TerminateBecauseOutOfMemory(size);
@@ -197,8 +198,8 @@ void* oom_killer_memalign_purgeable(struct _malloc_zone_t* zone,
                                     size_t size) {
   void* result = g_old_purgeable_zone.memalign(zone, alignment, size);
   // Only die if posix_memalign would have returned ENOMEM, since there are
-  // other reasons why NULL might be returned (see
-  // http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c ).
+  // other reasons why null might be returned. See posix_memalign() in 10.15's
+  // https://opensource.apple.com/source/libmalloc/libmalloc-283/src/malloc.c .
   if (!result && size && alignment >= sizeof(void*) &&
       base::bits::IsPowerOfTwo(alignment)) {
     TerminateBecauseOutOfMemory(size);
@@ -363,11 +364,11 @@ void InterceptAllocationsMac() {
 // === C malloc/calloc/valloc/realloc/posix_memalign ===
 
 // This approach is not perfect, as requests for amounts of memory larger than
-// MALLOC_ABSOLUTE_MAX_SIZE (currently SIZE_T_MAX - (2 * PAGE_SIZE)) will
-// still fail with a NULL rather than dying (see
-// http://opensource.apple.com/source/Libc/Libc-583/gen/malloc.c for details).
-// Unfortunately, it's the best we can do. Also note that this does not affect
-// allocations from non-default zones.
+// MALLOC_ABSOLUTE_MAX_SIZE (currently SIZE_T_MAX - (2 * PAGE_SIZE)) will still
+// fail with a NULL rather than dying (see malloc_zone_malloc() in
+// https://opensource.apple.com/source/libmalloc/libmalloc-283/src/malloc.c for
+// details). Unfortunately, it's the best we can do. Also note that this does
+// not affect allocations from non-default zones.
 
 #if !defined(ADDRESS_SANITIZER)
   // Don't do anything special on OOM for the malloc zones replaced by

base/allocator/malloc_zone_functions_mac.cc

@@ -40,6 +40,10 @@ void StoreZoneFunctions(const ChromeMallocZone* zone,
     functions->free_definite_size = zone->free_definite_size;
   }
 
+  // Note that zone version 8 introduced a pressure relief callback, and version
+  // 10 introduced a claimed address callback, but neither are allocation or
+  // deallocation callbacks and so aren't important to intercept.
+
   functions->context = zone;
 }
 

components/services/heap_profiling/public/cpp/profiling_client.cc

@@ -8,7 +8,6 @@
 #include <unordered_set>
 #include <vector>
 
-#include "base/allocator/allocator_interception_mac.h"
 #include "base/bind.h"
 #include "base/debug/stack_trace.h"
 #include "base/lazy_instance.h"
@@ -25,6 +24,10 @@
 #include "base/trace_event/cfi_backtrace_android.h"
 #endif
 
+#if defined(OS_APPLE)
+#include "base/allocator/allocator_interception_mac.h"
+#endif
+
 namespace heap_profiling {
 
 ProfilingClient::ProfilingClient() = default;

third_party/apple_apsl/README.chromium

@@ -7,11 +7,12 @@ License: Apple Public Source License 2.0
 Four files are excerpted here:
 
 malloc.h from:
-http://www.opensource.apple.com/source/Libc/Libc-763.11/include/malloc/malloc.h
+https://opensource.apple.com/source/libmalloc/libmalloc-283/include/malloc/malloc.h
 
 Modifications:
 - Modified #ifdef guards.
 - Removed everything but the definition of malloc_zone_t.
+- Added a header for the definition of boolean_t.
 - Renamed _malloc_zone_t to ChromeMallocZone to avoid possible name conflicts.
 
 CFRuntime.h from:

third_party/apple_apsl/malloc.h

@@ -24,6 +24,8 @@
 #ifndef THIRD_PARTY_APPLE_APSL_MALLOC_H_
 #define THIRD_PARTY_APPLE_APSL_MALLOC_H_
 
+#include <mach/boolean.h>
+
 typedef struct _ChromeMallocZone {
     /* Only zone implementors should depend on the layout of this structure;
     Regular callers should use the access functions below */
@@ -53,6 +55,13 @@ typedef struct _ChromeMallocZone {
 
     /* Empty out caches in the face of memory pressure. The callback may be NULL. Present in version >= 8. */
     size_t 	(*pressure_relief)(struct _malloc_zone_t *zone, size_t goal);
+
+    /*
+     * Checks whether an address might belong to the zone. May be NULL. Present in version >= 10.
+     * False positives are allowed (e.g. the pointer was freed, or it's in zone space that has
+     * not yet been allocated. False negatives are not allowed.
+     */
+    boolean_t (*claimed_address)(struct _malloc_zone_t *zone, void *ptr);
 } ChromeMallocZone;
 
 #endif  // THIRD_PARTY_APPLE_APSL_MALLOC_H_