[PA/shim] Support sized-delete

This is a change to add support to C++'s sized deallocation inside
Allocator Shim at Chrome. There is a planned change,
https://crrev.com/c/6445033, to enable sized deallocation support on the
compiler side. As current Shim does not export symbol with the extra
size parameter, the information is just ignored. Such information can be
useful in some scenarios and it would be great if Shim users can choose
to utilize the size info. Therefore, this patch makes following changes:

1. Adds new dispatcher functions:
  - `free_with_size_function`:
    `free()` but with known size; this was existing on `IS_APPLE`
    platforms as `free_definite_size_function` but added to other
    platforms.
  - `free_with_alignment_function`:
    `free()` but with known alignment.
  - `free_with_size_and_alignment_function`:
    `free()` but with known size and alignment.

2. Adds implementations of the functions above to the existing shim
   dispatchers.

3. Exported C++ symbols for sized deallocation now routes free requests
   through the new dispatcher functions.
   See `allocator_shim_override_cpp_symbols.h` for details.

4. Expanded an unit-test for C++ operators.
   See `allocator_shim_unittest.cc` for details.

5. Adds `shim_supports_sized_dealloc` gn arg, which is disabled by
   default. 3 are gated behind this flag and this patch is no-op
   unless this flag is explicitly flipped. 1-2 are intentionally not
   gated so that dispatcher users does not need to pay attention to
   build configuration in use. The new dispatcher functions are just
   not called when disabled.

Bug: 410190984, 410192659
Change-Id: I350fe94ce84a100ead22cb6eb9a557031fd57b29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6442080
Reviewed-by: Francois Pierre Doray <fdoray@chromium.org>
Reviewed-by: Takashi Sakamoto <tasak@google.com>
Mega-CQ: Mikihito Matsuura <mikt@google.com>
Commit-Queue: Mikihito Matsuura <mikt@google.com>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Reviewed-by: Paul Semel <paulsemel@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1450497}

base/allocator/dispatcher/internal/dispatcher_internal.h

@@ -195,6 +195,30 @@ struct DispatcherImpl {
     MUSTTAIL return allocator_dispatch_.next->free_function(address, context);
   }
 
+  static void FreeWithSizeFn(void* address, size_t size, void* context) {
+    DoNotifyFreeForShim(address);
+    MUSTTAIL return allocator_dispatch_.next->free_with_size_function(
+        address, size, context);
+  }
+
+  static void FreeWithAlignmentFn(void* address,
+                                  size_t alignment,
+                                  void* context) {
+    DoNotifyFreeForShim(address);
+    MUSTTAIL return allocator_dispatch_.next->free_with_alignment_function(
+        address, alignment, context);
+  }
+
+  static void FreeWithSizeAndAlignmentFn(void* address,
+                                         size_t size,
+                                         size_t alignment,
+                                         void* context) {
+    DoNotifyFreeForShim(address);
+    MUSTTAIL return allocator_dispatch_.next
+        ->free_with_size_and_alignment_function(address, size, alignment,
+                                                context);
+  }
+
   static unsigned BatchMallocFn(size_t size,
                                 void** results,
                                 unsigned num_requested,
@@ -219,12 +243,6 @@ struct DispatcherImpl {
         to_be_freed, num_to_be_freed, context);
   }
 
-  static void FreeDefiniteSizeFn(void* address, size_t size, void* context) {
-    DoNotifyFreeForShim(address);
-    MUSTTAIL return allocator_dispatch_.next->free_definite_size_function(
-        address, size, context);
-  }
-
   static void TryFreeDefaultFn(void* address, void* context) {
     DoNotifyFreeForShim(address);
     MUSTTAIL return allocator_dispatch_.next->try_free_default_function(
@@ -324,26 +342,28 @@ std::tuple<ObserverTypes*...> DispatcherImpl<ObserverTypes...>::s_observers;
 #if PA_BUILDFLAG(USE_ALLOCATOR_SHIM)
 template <typename... ObserverTypes>
 AllocatorDispatch DispatcherImpl<ObserverTypes...>::allocator_dispatch_ = {
-    AllocFn,                    // alloc_function
+    AllocFn,                     // alloc_function
-    AllocUncheckedFn,           // alloc_unchecked_function
+    AllocUncheckedFn,            // alloc_unchecked_function
-    AllocZeroInitializedFn,     // alloc_zero_initialized_function
+    AllocZeroInitializedFn,      // alloc_zero_initialized_function
-    AllocAlignedFn,             // alloc_aligned_function
+    AllocAlignedFn,              // alloc_aligned_function
-    ReallocFn,                  // realloc_function
+    ReallocFn,                   // realloc_function
-    ReallocUncheckedFn,         // realloc_unchecked_function
+    ReallocUncheckedFn,          // realloc_unchecked_function
-    FreeFn,                     // free_function
+    FreeFn,                      // free_function
-    nullptr,                    // get_size_estimate_function
+    FreeWithSizeFn,              // free_with_size_function
-    nullptr,                    // good_size_function
+    FreeWithAlignmentFn,         // free_with_alignment_function
-    nullptr,                    // claimed_address_function
+    FreeWithSizeAndAlignmentFn,  // free_with_size_and_alignment_function
-    BatchMallocFn,              // batch_malloc_function
+    nullptr,                     // get_size_estimate_function
-    BatchFreeFn,                // batch_free_function
+    nullptr,                     // good_size_function
-    FreeDefiniteSizeFn,         // free_definite_size_function
+    nullptr,                     // claimed_address_function
-    TryFreeDefaultFn,           // try_free_default_function
+    BatchMallocFn,               // batch_malloc_function
-    AlignedMallocFn,            // aligned_malloc_function
+    BatchFreeFn,                 // batch_free_function
-    AlignedMallocUncheckedFn,   // aligned_malloc_unchecked_function
+    TryFreeDefaultFn,            // try_free_default_function
-    AlignedReallocFn,           // aligned_realloc_function
+    AlignedMallocFn,             // aligned_malloc_function
-    AlignedReallocUncheckedFn,  // aligned_realloc_unchecked_function
+    AlignedMallocUncheckedFn,    // aligned_malloc_unchecked_function
-    AlignedFreeFn,              // aligned_free_function
+    AlignedReallocFn,            // aligned_realloc_function
-    nullptr                     // next
+    AlignedReallocUncheckedFn,   // aligned_realloc_unchecked_function
+    AlignedFreeFn,               // aligned_free_function
+    nullptr                      // next
 };
 #endif  // PA_BUILDFLAG(USE_ALLOCATOR_SHIM)
 

base/allocator/dispatcher/internal/dispatcher_internal_unittest.cc

@@ -146,12 +146,14 @@ struct AllocationEventDispatcherInternalTest : public DispatcherTest {
                                            &realloc_function,
                                            &realloc_unchecked_function,
                                            [](void*, void*) {},
+                                           [](void*, size_t, void*) {},
+                                           [](void*, size_t, void*) {},
+                                           [](void*, size_t, size_t, void*) {},
                                            &get_size_estimate_function,
                                            &good_size_function,
                                            &claimed_address_function,
                                            &batch_malloc_function,
                                            [](void**, unsigned, void*) {},
-                                           [](void*, size_t, void*) {},
                                            [](void*, void*) {},
                                            &aligned_malloc_function,
                                            &aligned_malloc_unchecked_function,
@@ -259,7 +261,7 @@ TEST_F(AllocationEventDispatcherInternalTest, VerifyAllocatorShimDataIsSet) {
   EXPECT_NE(nullptr, allocator_dispatch->free_function);
   EXPECT_NE(nullptr, allocator_dispatch->batch_malloc_function);
   EXPECT_NE(nullptr, allocator_dispatch->batch_free_function);
-  EXPECT_NE(nullptr, allocator_dispatch->free_definite_size_function);
+  EXPECT_NE(nullptr, allocator_dispatch->free_with_size_function);
   EXPECT_NE(nullptr, allocator_dispatch->try_free_default_function);
   EXPECT_NE(nullptr, allocator_dispatch->aligned_malloc_function);
   EXPECT_NE(nullptr, allocator_dispatch->aligned_malloc_unchecked_function);
@@ -515,7 +517,7 @@ TEST_F(AllocationEventDispatcherInternalTest,
 }
 
 TEST_F(AllocationEventDispatcherInternalTest,
-       VerifyAllocatorShimHooksTriggerCorrectly_free_definite_size_function) {
+       VerifyAllocatorShimHooksTriggerCorrectly_free_with_size_function) {
   std::array<ObserverMock, kMaximumNumberOfObservers> observers;
 
   for (auto& mock : observers) {
@@ -530,12 +532,12 @@ TEST_F(AllocationEventDispatcherInternalTest,
       GetNotificationHooks(CreateTupleOfPointers(observers));
 
   auto* const allocator_dispatch = dispatch_data.GetAllocatorDispatch();
-  EXPECT_NE(allocator_dispatch->free_definite_size_function, nullptr);
+  EXPECT_NE(allocator_dispatch->free_with_size_function, nullptr);
 
   allocator_dispatch->next = GetNextAllocatorDispatch();
 
-  allocator_dispatch->free_definite_size_function(GetAllocatedAddress(),
+  allocator_dispatch->free_with_size_function(GetAllocatedAddress(),
-                                                  GetAllocatedSize(), nullptr);
+                                              GetAllocatedSize(), nullptr);
 }
 
 TEST_F(AllocationEventDispatcherInternalTest,

base/allocator/partition_allocator/build_overrides/partition_alloc.gni

@@ -12,6 +12,7 @@ build_with_chromium = false
 # configuration.
 use_partition_alloc_as_malloc_default = false
 use_allocator_shim_default = false
+shim_supports_sized_dealloc_default = false
 enable_backup_ref_ptr_support_default = false
 enable_backup_ref_ptr_slow_checks_default = false
 enable_dangling_raw_ptr_checks_default = false

base/allocator/partition_allocator/partition_alloc.gni

@@ -142,6 +142,9 @@ declare_args() {
   # calls to PartitionAlloc, rather than some other platform allocator.
   use_partition_alloc_as_malloc = use_partition_alloc && use_allocator_shim &&
                                   use_partition_alloc_as_malloc_default
+
+  shim_supports_sized_dealloc =
+      use_allocator_shim && shim_supports_sized_dealloc_default
 }
 
 declare_args() {

base/allocator/partition_allocator/src/partition_alloc/BUILD.gn

@@ -183,6 +183,7 @@ pa_buildflag_header("buildflags") {
     "RAW_PTR_ZERO_ON_MOVE=$raw_ptr_zero_on_move",
     "REALLOC_GROWTH_FACTOR_MITIGATION=$partition_alloc_realloc_growth_factor_mitigation",
     "RECORD_ALLOC_INFO=$record_alloc_info",
+    "SHIM_SUPPORTS_SIZED_DEALLOC=$shim_supports_sized_dealloc",
     "SMALLER_PARTITION_COOKIE=$smaller_partition_cookie",
     "STACK_SCAN_SUPPORTED=$stack_scan_supported",
     "USE_ALLOCATOR_SHIM=$use_allocator_shim",

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_dispatch.h

@@ -31,7 +31,12 @@ struct AllocatorDispatch {
   using BatchFreeFn = void(void** to_be_freed,
                            unsigned num_to_be_freed,
                            void* context);
-  using FreeDefiniteSizeFn = void(void* ptr, size_t size, void* context);
+  using FreeWithSizeFn = void(void* ptr, size_t size, void* context);
+  using FreeWithAlignmentFn = void(void* ptr, size_t alignment, void* context);
+  using FreeWithSizeAndAlignmentFn = void(void* ptr,
+                                          size_t size,
+                                          size_t alignment,
+                                          void* context);
   using TryFreeDefaultFn = void(void* ptr, void* context);
   using AlignedMallocFn = void*(size_t size, size_t alignment, void* context);
   using AlignedMallocUncheckedFn = void*(size_t size,
@@ -54,14 +59,16 @@ struct AllocatorDispatch {
   ReallocFn* realloc_function;
   ReallocUncheckedFn* realloc_unchecked_function;
   FreeFn* free_function;
+  FreeWithSizeFn* free_with_size_function;
+  FreeWithAlignmentFn* free_with_alignment_function;
+  FreeWithSizeAndAlignmentFn* free_with_size_and_alignment_function;
   GetSizeEstimateFn* get_size_estimate_function;
   GoodSizeFn* good_size_function;
-  // claimed_address, batch_malloc, batch_free, free_definite_size and
+  // claimed_address, batch_malloc, batch_free and
   // try_free_default are specific to the OSX and iOS allocators.
   ClaimedAddressFn* claimed_address_function;
   BatchMallocFn* batch_malloc_function;
   BatchFreeFn* batch_free_function;
-  FreeDefiniteSizeFn* free_definite_size_function;
   TryFreeDefaultFn* try_free_default_function;
   // _aligned_malloc, _aligned_realloc, and _aligned_free are specific to the
   // Windows allocator.
@@ -125,12 +132,14 @@ struct AllocatorDispatch {
     COPY_IF_NULLPTR(realloc_function);
     COPY_IF_NULLPTR(realloc_unchecked_function);
     COPY_IF_NULLPTR(free_function);
+    COPY_IF_NULLPTR(free_with_size_function);
+    COPY_IF_NULLPTR(free_with_alignment_function);
+    COPY_IF_NULLPTR(free_with_size_and_alignment_function);
     COPY_IF_NULLPTR(get_size_estimate_function);
     COPY_IF_NULLPTR(good_size_function);
     COPY_IF_NULLPTR(claimed_address_function);
     COPY_IF_NULLPTR(batch_malloc_function);
     COPY_IF_NULLPTR(batch_free_function);
-    COPY_IF_NULLPTR(free_definite_size_function);
     COPY_IF_NULLPTR(try_free_default_function);
     COPY_IF_NULLPTR(aligned_malloc_function);
     COPY_IF_NULLPTR(aligned_malloc_unchecked_function);

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_apple_zoned_malloc.cc

@@ -40,6 +40,26 @@ void FreeImpl(void* ptr, void* context) {
   functions.free(reinterpret_cast<struct _malloc_zone_t*>(context), ptr);
 }
 
+void FreeWithSizeImpl(void* ptr, size_t size, void* context) {
+  MallocZoneFunctions& functions = GetFunctionsForZone(context);
+  functions.free_definite_size(
+      reinterpret_cast<struct _malloc_zone_t*>(context), ptr, size);
+}
+
+void FreeWithAlignmentImpl(void* ptr, size_t, void* context) {
+  MallocZoneFunctions& functions = GetFunctionsForZone(context);
+  functions.free(reinterpret_cast<struct _malloc_zone_t*>(context), ptr);
+}
+
+void FreeWithSizeAndAlignmentImpl(void* ptr,
+                                  size_t size,
+                                  size_t,
+                                  void* context) {
+  MallocZoneFunctions& functions = GetFunctionsForZone(context);
+  functions.free_definite_size(
+      reinterpret_cast<struct _malloc_zone_t*>(context), ptr, size);
+}
+
 size_t GetSizeEstimateImpl(void* ptr, void* context) {
   MallocZoneFunctions& functions = GetFunctionsForZone(context);
   return functions.size(reinterpret_cast<struct _malloc_zone_t*>(context), ptr);
@@ -84,12 +104,6 @@ void BatchFreeImpl(void** to_be_freed,
                        to_be_freed, num_to_be_freed);
 }
 
-void FreeDefiniteSizeImpl(void* ptr, size_t size, void* context) {
-  MallocZoneFunctions& functions = GetFunctionsForZone(context);
-  functions.free_definite_size(
-      reinterpret_cast<struct _malloc_zone_t*>(context), ptr, size);
-}
-
 void TryFreeDefaultImpl(void* ptr, void* context) {
   MallocZoneFunctions& functions = GetFunctionsForZone(context);
   if (functions.try_free_default) {
@@ -102,26 +116,28 @@ void TryFreeDefaultImpl(void* ptr, void* context) {
 }  // namespace
 
 const AllocatorDispatch AllocatorDispatch::default_dispatch = {
-    &MallocImpl,           /* alloc_function */
+    &MallocImpl,                   /* alloc_function */
-    &MallocImpl,           /* alloc_unchecked_function */
+    &MallocImpl,                   /* alloc_unchecked_function */
-    &CallocImpl,           /* alloc_zero_initialized_function */
+    &CallocImpl,                   /* alloc_zero_initialized_function */
-    &MemalignImpl,         /* alloc_aligned_function */
+    &MemalignImpl,                 /* alloc_aligned_function */
-    &ReallocImpl,          /* realloc_function */
+    &ReallocImpl,                  /* realloc_function */
-    &ReallocImpl,          /* realloc_unchecked_function */
+    &ReallocImpl,                  /* realloc_unchecked_function */
-    &FreeImpl,             /* free_function */
+    &FreeImpl,                     /* free_function */
-    &GetSizeEstimateImpl,  /* get_size_estimate_function */
+    &FreeWithSizeImpl,             /* free_with_size_function */
-    &GoodSizeImpl,         /* good_size_function */
+    &FreeWithAlignmentImpl,        /* free_with_size_function */
-    &ClaimedAddressImpl,   /* claimed_address_function */
+    &FreeWithSizeAndAlignmentImpl, /* free_with_size_function */
-    &BatchMallocImpl,      /* batch_malloc_function */
+    &GetSizeEstimateImpl,          /* get_size_estimate_function */
-    &BatchFreeImpl,        /* batch_free_function */
+    &GoodSizeImpl,                 /* good_size_function */
-    &FreeDefiniteSizeImpl, /* free_definite_size_function */
+    &ClaimedAddressImpl,           /* claimed_address_function */
-    &TryFreeDefaultImpl,   /* try_free_default_function */
+    &BatchMallocImpl,              /* batch_malloc_function */
-    nullptr,               /* aligned_malloc_function */
+    &BatchFreeImpl,                /* batch_free_function */
-    nullptr,               /* aligned_malloc_unchecked_function */
+    &TryFreeDefaultImpl,           /* try_free_default_function */
-    nullptr,               /* aligned_realloc_function */
+    nullptr,                       /* aligned_malloc_function */
-    nullptr,               /* aligned_realloc_unchecked_function */
+    nullptr,                       /* aligned_malloc_unchecked_function */
-    nullptr,               /* aligned_free_function */
+    nullptr,                       /* aligned_realloc_function */
-    nullptr,               /* next */
+    nullptr,                       /* aligned_realloc_unchecked_function */
+    nullptr,                       /* aligned_free_function */
+    nullptr,                       /* next */
 };
 
 }  // namespace allocator_shim

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_glibc.cc

@@ -88,6 +88,21 @@ void GlibcFree(void* address, void* context) {
   __libc_free(address);
 }
 
+void GlibcFreeWithSize(void* address, size_t, void* context) {
+  __libc_free(address);
+}
+
+void GlibcFreeWithAlignment(void* address, size_t, void* context) {
+  __libc_free(address);
+}
+
+void GlibcFreeWithSizeAndAlignment(void* address,
+                                   size_t,
+                                   size_t,
+                                   void* context) {
+  __libc_free(address);
+}
+
 PA_NO_SANITIZE("cfi-icall")
 size_t GlibcGetSizeEstimate(void* address, void* context) {
   // glibc does not expose an alias to resolve malloc_usable_size. Dynamically
@@ -112,17 +127,21 @@ const AllocatorDispatch AllocatorDispatch::default_dispatch = {
     &GlibcRealloc,          /* realloc_function */
     &GlibcUncheckedRealloc, /* realloc_unchecked_function */
     &GlibcFree,             /* free_function */
-    &GlibcGetSizeEstimate,  /* get_size_estimate_function */
+    GlibcFreeWithSize,      /* free_with_size_function */
-    nullptr,                /* good_size_function */
+    GlibcFreeWithAlignment,
-    nullptr,                /* claimed_address */
+    /* free_with_alignment_function */
-    nullptr,                /* batch_malloc_function */
+    GlibcFreeWithSizeAndAlignment,
-    nullptr,                /* batch_free_function */
+    /* free_with_size_and_alignment_function */
-    nullptr,                /* free_definite_size_function */
+    &GlibcGetSizeEstimate, /* get_size_estimate_function */
-    nullptr,                /* try_free_default_function */
+    nullptr,               /* good_size_function */
-    nullptr,                /* aligned_malloc_function */
+    nullptr,               /* claimed_address */
-    nullptr,                /* aligned_malloc_unchecked_function */
+    nullptr,               /* batch_malloc_function */
-    nullptr,                /* aligned_realloc_function */
+    nullptr,               /* batch_free_function */
-    nullptr,                /* aligned_realloc_unchecked_function */
+    nullptr,               /* try_free_default_function */
-    nullptr,                /* aligned_free_function */
+    nullptr,               /* aligned_malloc_function */
-    nullptr,                /* next */
+    nullptr,               /* aligned_malloc_unchecked_function */
+    nullptr,               /* aligned_realloc_function */
+    nullptr,               /* aligned_realloc_unchecked_function */
+    nullptr,               /* aligned_free_function */
+    nullptr,               /* next */
 };

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_linker_wrapped_symbols.cc

@@ -49,6 +49,21 @@ void RealFree(void* address, void* context) {
   __real_free(address);
 }
 
+void RealFreeWithSize(void* address, size_t, void* context) {
+  __real_free(address);
+}
+
+void RealFreeWithAlignment(void* address, size_t, void* context) {
+  __real_free(address);
+}
+
+void RealFreeWithSizeAndAlignment(void* address,
+                                  size_t,
+                                  size_t,
+                                  void* context) {
+  __real_free(address);
+}
+
 size_t RealSizeEstimate(void* address, void* context) {
   return __real_malloc_usable_size(address);
 }
@@ -56,24 +71,26 @@ size_t RealSizeEstimate(void* address, void* context) {
 }  // namespace
 
 const AllocatorDispatch AllocatorDispatch::default_dispatch = {
-    &RealMalloc,       /* alloc_function */
+    &RealMalloc,                   /* alloc_function */
-    &RealMalloc,       /* alloc_unchecked_function */
+    &RealMalloc,                   /* alloc_unchecked_function */
-    &RealCalloc,       /* alloc_zero_initialized_function */
+    &RealCalloc,                   /* alloc_zero_initialized_function */
-    &RealMemalign,     /* alloc_aligned_function */
+    &RealMemalign,                 /* alloc_aligned_function */
-    &RealRealloc,      /* realloc_function */
+    &RealRealloc,                  /* realloc_function */
-    &RealRealloc,      /* realloc_unchecked_function */
+    &RealRealloc,                  /* realloc_unchecked_function */
-    &RealFree,         /* free_function */
+    &RealFree,                     /* free_function */
-    &RealSizeEstimate, /* get_size_estimate_function */
+    &RealFreeWithSize,             /* free_with_size_function */
-    nullptr,           /* good_size_function */
+    &RealFreeWithAlignment,        /* free_with_alignment_function */
-    nullptr,           /* claimed_address */
+    &RealFreeWithSizeAndAlignment, /* free_with_size_and_alignment_function */
-    nullptr,           /* batch_malloc_function */
+    &RealSizeEstimate,             /* get_size_estimate_function */
-    nullptr,           /* batch_free_function */
+    nullptr,                       /* good_size_function */
-    nullptr,           /* free_definite_size_function */
+    nullptr,                       /* claimed_address */
-    nullptr,           /* try_free_default_function */
+    nullptr,                       /* batch_malloc_function */
-    nullptr,           /* aligned_malloc_function */
+    nullptr,                       /* batch_free_function */
-    nullptr,           /* aligned_malloc_unchecked_function */
+    nullptr,                       /* try_free_default_function */
-    nullptr,           /* aligned_realloc_function */
+    nullptr,                       /* aligned_malloc_function */
-    nullptr,           /* aligned_realloc_unchecked_function */
+    nullptr,                       /* aligned_malloc_unchecked_function */
-    nullptr,           /* aligned_free_function */
+    nullptr,                       /* aligned_realloc_function */
-    nullptr,           /* next */
+    nullptr,                       /* aligned_realloc_unchecked_function */
+    nullptr,                       /* aligned_free_function */
+    nullptr,                       /* next */
 };

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_partition_alloc.cc

@@ -435,25 +435,46 @@ PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::Free(
       object);
 }
 
-#if PA_BUILDFLAG(IS_APPLE)
-// Normal free() path on Apple OSes:
-// 1. size = GetSizeEstimate(ptr);
-// 2. if (size) FreeDefiniteSize(ptr, size)
-//
-// So we don't need to re-check that the pointer is owned in Free(), and we
-// can use the size.
 // static
 template <partition_alloc::AllocFlags base_alloc_flags,
           partition_alloc::FreeFlags base_free_flags>
-void PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::
+PA_ALWAYS_INLINE void
-    FreeDefiniteSize(void* address, size_t size, void* context) {
+PartitionAllocFunctionsInternal<base_alloc_flags,
-  partition_alloc::ScopedDisallowAllocations guard{};
+                                base_free_flags>::FreeWithSize(void* object,
+                                                               size_t size,
+                                                               void* context) {
   // TODO(lizeb): Optimize PartitionAlloc to use the size information. This is
   // still useful though, as we avoid double-checking that the address is owned.
-  partition_alloc::PartitionRoot::FreeInlineInUnknownRoot<base_free_flags>(
+  PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::Free(
-      address);
+      object, context);
+}
+
+// static
+template <partition_alloc::AllocFlags base_alloc_flags,
+          partition_alloc::FreeFlags base_free_flags>
+PA_ALWAYS_INLINE void
+PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::
+    FreeWithAlignment(void* object, size_t alignment, void* context) {
+  // TODO(lizeb): Optimize PartitionAlloc to use the size information. This is
+  // still useful though, as we avoid double-checking that the address is owned.
+  PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::Free(
+      object, context);
+}
+
+// static
+template <partition_alloc::AllocFlags base_alloc_flags,
+          partition_alloc::FreeFlags base_free_flags>
+PA_ALWAYS_INLINE void PartitionAllocFunctionsInternal<
+    base_alloc_flags,
+    base_free_flags>::FreeWithSizeAndAlignment(void* object,
+                                               size_t size,
+                                               size_t alignment,
+                                               void* context) {
+  // TODO(lizeb): Optimize PartitionAlloc to use the size information. This is
+  // still useful though, as we avoid double-checking that the address is owned.
+  PartitionAllocFunctionsInternal<base_alloc_flags, base_free_flags>::Free(
+      object, context);
 }
-#endif  // PA_BUILDFLAG(IS_APPLE)
 
 // static
 template <partition_alloc::AllocFlags base_alloc_flags,

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_partition_alloc.h

@@ -62,9 +62,14 @@ class PartitionAllocFunctionsInternal {
 
   static void Free(void* object, void* context);
 
-#if PA_BUILDFLAG(IS_APPLE)
+  static void FreeWithSize(void* object, size_t size, void* context);
-  static void FreeDefiniteSize(void* address, size_t size, void* context);
+
-#endif  // PA_BUILDFLAG(IS_APPLE)
+  static void FreeWithAlignment(void* object, size_t alignment, void* context);
+
+  static void FreeWithSizeAndAlignment(void* object,
+                                       size_t size,
+                                       size_t alignment,
+                                       void* context);
 
   static size_t GetSizeEstimate(void* address, void* context);
 
@@ -89,14 +94,17 @@ class PartitionAllocFunctionsInternal {
 
   static constexpr AllocatorDispatch MakeDispatch() {
     return {
-        &Malloc,            // alloc_function
+        &Malloc,                    // alloc_function
-        &MallocUnchecked,   // alloc_unchecked_function
+        &MallocUnchecked,           // alloc_unchecked_function
-        &Calloc,            // alloc_zero_initialized_function
+        &Calloc,                    // alloc_zero_initialized_function
-        &Memalign,          // alloc_aligned_function
+        &Memalign,                  // alloc_aligned_function
-        &Realloc,           // realloc_function
+        &Realloc,                   // realloc_function
-        &ReallocUnchecked,  // realloc_unchecked_function
+        &ReallocUnchecked,          // realloc_unchecked_function
-        &Free,              // free_function
+        &Free,                      // free_function
-        &GetSizeEstimate,   // get_size_estimate_function
+        &FreeWithSize,              // free_with_size_function
+        &FreeWithAlignment,         // free_with_alignment_function
+        &FreeWithSizeAndAlignment,  // free_with_size_and_alignment_function
+        &GetSizeEstimate,           // get_size_estimate_function
 #if PA_BUILDFLAG(IS_APPLE)
         &GoodSize,        // good_size
         &ClaimedAddress,  // claimed_address
@@ -107,15 +115,10 @@ class PartitionAllocFunctionsInternal {
         &BatchMalloc,  // batch_malloc_function
         &BatchFree,    // batch_free_function
 #if PA_BUILDFLAG(IS_APPLE)
-        // On Apple OSes, free_definite_size() is always called from free(),
-        // since get_size_estimate() is used to determine whether an allocation
-        // belongs to the current zone. It makes sense to optimize for it.
-        &FreeDefiniteSize,
         // On Apple OSes, try_free_default() is sometimes called as an
         // optimization of free().
         &TryFreeDefault,
 #else
-        nullptr,  // free_definite_size_function
         nullptr,  // try_free_default_function
 #endif
         &AlignedAlloc,             // aligned_malloc_function

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_partition_alloc_with_advanced_checks.cc

@@ -58,6 +58,28 @@ void DelegatedFreeFn(void* address, void* context) {
   PA_MUSTTAIL return delegate->free_function(address, context);
 }
 
+void DelegatedFreeWithSizeFn(void* address, size_t size, void* context) {
+  const AllocatorDispatch* delegate = GetDelegate();
+  PA_MUSTTAIL return delegate->free_with_size_function(address, size, context);
+}
+
+void DelegatedFreeWithAlignmentFn(void* address,
+                                  size_t alignment,
+                                  void* context) {
+  const AllocatorDispatch* delegate = GetDelegate();
+  PA_MUSTTAIL return delegate->free_with_alignment_function(address, alignment,
+                                                            context);
+}
+
+void DelegatedFreeWithSizeAndAlignmentFn(void* address,
+                                         size_t size,
+                                         size_t alignment,
+                                         void* context) {
+  const AllocatorDispatch* delegate = GetDelegate();
+  PA_MUSTTAIL return delegate->free_with_size_and_alignment_function(
+      address, size, alignment, context);
+}
+
 size_t DelegatedGetSizeEstimateFn(void* address, void* context) {
   const AllocatorDispatch* delegate = GetDelegate();
   PA_MUSTTAIL return delegate->get_size_estimate_function(address, context);
@@ -90,12 +112,6 @@ void DelegatedBatchFreeFn(void** to_be_freed,
                                                    context);
 }
 
-void DelegatedFreeDefiniteSizeFn(void* address, size_t size, void* context) {
-  const AllocatorDispatch* delegate = GetDelegate();
-  PA_MUSTTAIL return delegate->free_definite_size_function(address, size,
-                                                           context);
-}
-
 void DelegatedTryFreeDefaultFn(void* address, void* context) {
   const AllocatorDispatch* delegate = GetDelegate();
   PA_MUSTTAIL return delegate->try_free_default_function(address, context);
@@ -158,7 +174,7 @@ void InstallCustomDispatch(AllocatorDispatch* dispatch) {
   PA_DCHECK(dispatch->batch_malloc_function != nullptr);
   PA_DCHECK(dispatch->batch_free_function != nullptr);
 #if PA_BUILDFLAG(IS_APPLE)
-  PA_DCHECK(dispatch->free_definite_size_function != nullptr);
+  PA_DCHECK(dispatch->free_with_size_function != nullptr);
   PA_DCHECK(dispatch->try_free_default_function != nullptr);
 #endif  // PA_BUILDFLAG(IS_APPLE)
   PA_DCHECK(dispatch->aligned_malloc_function != nullptr);
@@ -210,12 +226,15 @@ const AllocatorDispatch AllocatorDispatch::default_dispatch = {
     .realloc_function = &DelegatedReallocFn,
     .realloc_unchecked_function = &DelegatedReallocUncheckedFn,
     .free_function = &DelegatedFreeFn,
+    .free_with_size_function = &DelegatedFreeWithSizeFn,
+    .free_with_alignment_function = &DelegatedFreeWithAlignmentFn,
+    .free_with_size_and_alignment_function =
+        &DelegatedFreeWithSizeAndAlignmentFn,
     .get_size_estimate_function = &DelegatedGetSizeEstimateFn,
     .good_size_function = &DelegatedGoodSizeFn,
     .claimed_address_function = &DelegatedClaimedAddressFn,
     .batch_malloc_function = &DelegatedBatchMallocFn,
     .batch_free_function = &DelegatedBatchFreeFn,
-    .free_definite_size_function = &DelegatedFreeDefiniteSizeFn,
     .try_free_default_function = &DelegatedTryFreeDefaultFn,
     .aligned_malloc_function = &DelegatedAlignedMallocFn,
     .aligned_malloc_unchecked_function = &DelegatedAlignedMallocUncheckedFn,

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_default_dispatch_to_winheap.cc

@@ -43,6 +43,23 @@ void DefaultWinHeapFreeImpl(void* address, void* context) {
   allocator_shim::WinHeapFree(address);
 }
 
+void DefaultWinHeapFreeWithSizeImpl(void* address, size_t size, void* context) {
+  allocator_shim::WinHeapFree(address);
+}
+
+void DefaultWinHeapFreeWithAlignmentImpl(void* address,
+                                         size_t alignment,
+                                         void* context) {
+  allocator_shim::WinHeapFree(address);
+}
+
+void DefaultWinHeapFreeWithSizeAndAlignmentImpl(void* address,
+                                                size_t size,
+                                                size_t alignment,
+                                                void* context) {
+  allocator_shim::WinHeapFree(address);
+}
+
 size_t DefaultWinHeapGetSizeEstimateImpl(void* address, void* context) {
   return allocator_shim::WinHeapGetSizeEstimate(address);
 }
@@ -77,12 +94,14 @@ constexpr AllocatorDispatch AllocatorDispatch::default_dispatch = {
     &DefaultWinHeapReallocImpl,
     &DefaultWinHeapReallocImpl, /* realloc_unchecked_function */
     &DefaultWinHeapFreeImpl,
+    &DefaultWinHeapFreeWithSizeImpl,
+    &DefaultWinHeapFreeWithAlignmentImpl,
+    &DefaultWinHeapFreeWithSizeAndAlignmentImpl,
     &DefaultWinHeapGetSizeEstimateImpl,
     nullptr, /* good_size */
     nullptr, /* claimed_address */
     nullptr, /* batch_malloc_function */
     nullptr, /* batch_free_function */
-    nullptr, /* free_definite_size_function */
     nullptr, /* try_free_default_function */
     &DefaultWinHeapAlignedMallocImpl,
     &DefaultWinHeapAlignedMallocImpl, /* aligned_malloc_unchecked_function */

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_dispatch_to_noop_on_free.cc

@@ -15,35 +15,44 @@ namespace {
 
 void FreeFn(void* address, void* context) {}
 
-void BatchFreeFn(void** to_be_freed, unsigned num_to_be_freed, void* context) {}
+void FreeWithSizeFn(void* address, size_t size, void* context) {}
 
-void FreeDefiniteSizeFn(void* address, size_t size, void* context) {}
+void FreeWithAlignmentFn(void* address, size_t alignment, void* context) {}
+
+void FreeWithSizeAndAlignmentFn(void* address,
+                                size_t size,
+                                size_t alignment,
+                                void* context) {}
+
+void BatchFreeFn(void** to_be_freed, unsigned num_to_be_freed, void* context) {}
 
 void TryFreeDefaultFn(void* address, void* context) {}
 
 static void AlignedFreeFn(void* address, void* context) {}
 
 AllocatorDispatch allocator_dispatch = {
-    nullptr,             // alloc_function
+    nullptr,                     // alloc_function
-    nullptr,             // alloc_unchecked_function
+    nullptr,                     // alloc_unchecked_function
-    nullptr,             // alloc_zero_initialized_function
+    nullptr,                     // alloc_zero_initialized_function
-    nullptr,             // alloc_aligned_function
+    nullptr,                     // alloc_aligned_function
-    nullptr,             // realloc_function
+    nullptr,                     // realloc_function
-    nullptr,             // realloc_unchecked_function
+    nullptr,                     // realloc_unchecked_function
-    FreeFn,              // free_function
+    FreeFn,                      // free_function
-    nullptr,             // get_size_estimate_function
+    FreeWithSizeFn,              // free_definite_size_function
-    nullptr,             // good_size_function
+    FreeWithAlignmentFn,         // free_with_alignment_function
-    nullptr,             // claimed_address_function
+    FreeWithSizeAndAlignmentFn,  // free_with_size_and_alignment_function
-    nullptr,             // batch_malloc_function
+    nullptr,                     // get_size_estimate_function
-    BatchFreeFn,         // batch_free_function
+    nullptr,                     // good_size_function
-    FreeDefiniteSizeFn,  // free_definite_size_function
+    nullptr,                     // claimed_address_function
-    TryFreeDefaultFn,    // try_free_default_function
+    nullptr,                     // batch_malloc_function
-    nullptr,             // aligned_malloc_function
+    BatchFreeFn,                 // batch_free_function
-    nullptr,             // aligned_malloc_unchecked_function
+    TryFreeDefaultFn,            // try_free_default_function
-    nullptr,             // aligned_realloc_function
+    nullptr,                     // aligned_malloc_function
-    nullptr,             // aligned_realloc_unchecked_function
+    nullptr,                     // aligned_malloc_unchecked_function
-    AlignedFreeFn,       // aligned_free_function
+    nullptr,                     // aligned_realloc_function
-    nullptr              // next
+    nullptr,                     // aligned_realloc_unchecked_function
+    AlignedFreeFn,               // aligned_free_function
+    nullptr                      // next
 };
 
 }  // namespace

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_override_apple_default_zone.h

@@ -177,7 +177,7 @@ void* MallocZoneMemalign(malloc_zone_t* zone, size_t alignment, size_t size) {
 }
 
 void MallocZoneFreeDefiniteSize(malloc_zone_t* zone, void* ptr, size_t size) {
-  return ShimFreeDefiniteSize(ptr, size, nullptr);
+  return ShimFreeWithSize(ptr, size, nullptr);
 }
 
 unsigned MallocZoneBatchMalloc(malloc_zone_t* zone,

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_override_apple_symbols.h

@@ -62,7 +62,7 @@ MallocZoneFunctions MallocZoneFunctionsToReplaceDefault() {
   };
   new_functions.free_definite_size = [](malloc_zone_t* zone, void* ptr,
                                         size_t size) {
-    ShimFreeDefiniteSize(ptr, size, zone);
+    ShimFreeWithSize(ptr, size, zone);
   };
   new_functions.try_free_default = [](malloc_zone_t* zone, void* ptr) {
     ShimTryFreeDefault(ptr, zone);

base/allocator/partition_allocator/src/partition_alloc/shim/allocator_shim_override_cpp_symbols.h

@@ -102,17 +102,21 @@ SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
 #endif
 }
 
-SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p, size_t) __THROW {
+SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p, size_t size) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithSize(p, size);
 #else
   ShimCppDelete(p);
 #endif
 }
 
-SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p, size_t) __THROW {
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p, size_t size) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithSize(p, size);
 #else
   ShimCppDelete(p);
 #endif
@@ -137,30 +141,36 @@ SHIM_CPP_SYMBOLS_EXPORT void* operator new(std::size_t size,
 #endif
 }
 
-SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
+SHIM_CPP_SYMBOLS_EXPORT void operator delete(
-                                             std::align_val_t) __THROW {
+    void* p,
+    std::align_val_t alignment) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithAlignment(p, static_cast<size_t>(alignment));
+#else
+  ShimCppDelete(p);
+#endif
+}
+
+SHIM_CPP_SYMBOLS_EXPORT void
+operator delete(void* p, std::size_t size, std::align_val_t alignment) __THROW {
+#if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
+  free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithSizeAndAlignment(p, size, static_cast<size_t>(alignment));
 #else
   ShimCppDelete(p);
 #endif
 }
 
 SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
-                                             std::size_t size,
+                                             std::align_val_t alignment,
-                                             std::align_val_t) __THROW {
-#if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
-  free(p);
-#else
-  ShimCppDelete(p);
-#endif
-}
-
-SHIM_CPP_SYMBOLS_EXPORT void operator delete(void* p,
-                                             std::align_val_t,
                                              const std::nothrow_t&) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithAlignment(p, static_cast<size_t>(alignment));
 #else
   ShimCppDelete(p);
 #endif
@@ -185,30 +195,38 @@ SHIM_CPP_SYMBOLS_EXPORT void* operator new[](std::size_t size,
 #endif
 }
 
-SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](
-                                               std::align_val_t) __THROW {
+    void* p,
+    std::align_val_t alignment) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithAlignment(p, static_cast<size_t>(alignment));
+#else
+  ShimCppDelete(p);
+#endif
+}
+
+SHIM_CPP_SYMBOLS_EXPORT void operator delete[](
+    void* p,
+    std::size_t size,
+    std::align_val_t alignment) __THROW {
+#if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
+  free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithSizeAndAlignment(p, size, static_cast<size_t>(alignment));
 #else
   ShimCppDelete(p);
 #endif
 }
 
 SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
-                                               std::size_t size,
+                                               std::align_val_t alignment,
-                                               std::align_val_t) __THROW {
-#if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
-  free(p);
-#else
-  ShimCppDelete(p);
-#endif
-}
-
-SHIM_CPP_SYMBOLS_EXPORT void operator delete[](void* p,
-                                               std::align_val_t,
                                                const std::nothrow_t&) __THROW {
 #if PA_BUILDFLAG(FORWARD_THROUGH_MALLOC)
   free(p);
+#elif PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+  ShimCppDeleteWithAlignment(p, static_cast<size_t>(alignment));
 #else
   ShimCppDelete(p);
 #endif

base/allocator/partition_allocator/src/partition_alloc/shim/shim_alloc_functions.h

@@ -112,6 +112,42 @@ PA_ALWAYS_INLINE void ShimCppDelete(void* address) {
   return chain_head->free_function(address, context);
 }
 
+#if PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+PA_ALWAYS_INLINE void ShimCppDeleteWithSize(void* address, size_t size) {
+  const allocator_shim::AllocatorDispatch* const chain_head =
+      allocator_shim::internal::GetChainHead();
+  void* context = nullptr;
+#if PA_BUILDFLAG(IS_APPLE) && !PA_BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
+  context = malloc_default_zone();
+#endif
+  return chain_head->free_with_size_function(address, size, context);
+}
+
+PA_ALWAYS_INLINE void ShimCppDeleteWithAlignment(void* address,
+                                                 size_t alignment) {
+  const allocator_shim::AllocatorDispatch* const chain_head =
+      allocator_shim::internal::GetChainHead();
+  void* context = nullptr;
+#if PA_BUILDFLAG(IS_APPLE) && !PA_BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
+  context = malloc_default_zone();
+#endif
+  return chain_head->free_with_alignment_function(address, alignment, context);
+}
+
+PA_ALWAYS_INLINE void ShimCppDeleteWithSizeAndAlignment(void* address,
+                                                        size_t size,
+                                                        size_t alignment) {
+  const allocator_shim::AllocatorDispatch* const chain_head =
+      allocator_shim::internal::GetChainHead();
+  void* context = nullptr;
+#if PA_BUILDFLAG(IS_APPLE) && !PA_BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC)
+  context = malloc_default_zone();
+#endif
+  return chain_head->free_with_size_and_alignment_function(address, size,
+                                                           alignment, context);
+}
+#endif  // PA_BUILDFLAG(SHIM_SUPPORTS_SIZED_DEALLOC)
+
 PA_ALWAYS_INLINE void* ShimMalloc(size_t size, void* context) {
   const allocator_shim::AllocatorDispatch* const chain_head =
       allocator_shim::internal::GetChainHead();
@@ -213,6 +249,12 @@ PA_ALWAYS_INLINE void ShimFree(void* address, void* context) {
   return chain_head->free_function(address, context);
 }
 
+PA_ALWAYS_INLINE void ShimFreeWithSize(void* ptr, size_t size, void* context) {
+  const allocator_shim::AllocatorDispatch* const chain_head =
+      allocator_shim::internal::GetChainHead();
+  return chain_head->free_with_size_function(ptr, size, context);
+}
+
 PA_ALWAYS_INLINE size_t ShimGetSizeEstimate(const void* address,
                                             void* context) {
   const allocator_shim::AllocatorDispatch* const chain_head =
@@ -251,14 +293,6 @@ PA_ALWAYS_INLINE void ShimBatchFree(void** to_be_freed,
   return chain_head->batch_free_function(to_be_freed, num_to_be_freed, context);
 }
 
-PA_ALWAYS_INLINE void ShimFreeDefiniteSize(void* ptr,
-                                           size_t size,
-                                           void* context) {
-  const allocator_shim::AllocatorDispatch* const chain_head =
-      allocator_shim::internal::GetChainHead();
-  return chain_head->free_definite_size_function(ptr, size, context);
-}
-
 PA_ALWAYS_INLINE void ShimTryFreeDefault(void* ptr, void* context) {
   const allocator_shim::AllocatorDispatch* const chain_head =
       allocator_shim::internal::GetChainHead();

base/debug/stack_trace_unittest.cc

@@ -205,12 +205,14 @@ allocator_shim::AllocatorDispatch g_bad_malloc_dispatch = {
     &BadRealloc,        /* realloc_function */
     &BadRealloc,        /* realloc_unchecked_function */
     &BadFree,           /* free_function */
+    nullptr,            /* free_with_size_function */
+    nullptr,            /* free_with_alignment_function */
+    nullptr,            /* free_with_size_and_alignment_function */
     nullptr,            /* get_size_estimate_function */
     nullptr,            /* good_size_function */
     nullptr,            /* claimed_address_function */
     nullptr,            /* batch_malloc_function */
     nullptr,            /* batch_free_function */
-    nullptr,            /* free_definite_size_function */
     nullptr,            /* try_free_default_function */
     &BadAlignedAlloc,   /* aligned_malloc_function */
     &BadAlignedAlloc,   /* aligned_malloc_unchecked_function */

build_overrides/partition_alloc.gni

@@ -111,6 +111,8 @@ if (is_win && is_component_build && (!use_custom_libcxx || libcxx_is_shared)) {
   use_allocator_shim_default = false
 }
 
+shim_supports_sized_dealloc_default = use_sized_deallocation
+
 use_partition_alloc_as_malloc_default =
     use_allocator_shim_default && _is_partition_alloc_everywhere_platform &&
     !_disable_partition_alloc_everywhere

components/gwp_asan/client/extreme_lightweight_detector_malloc_shims.cc

@@ -96,7 +96,7 @@ bool TryInitSlow() {
   //
   // This code runs only on the codepaths of deallocations (`free`, `delete`,
   // etc.) and _never_ runs on the codepaths of allocations (`malloc`, `new`,
-  // etc.) because this allocator shim hooks only FreeFn, FreeDefiniteSizeFn,
+  // etc.) because this allocator shim hooks only FreeFn, FreeWithSizeFn,
   // etc. So, it's safe to allocate memory here as it doesn't recurse, however,
   // it's _NOT_ allowed to deallocate memory here as it _does_ recurse.
   //
@@ -218,16 +218,40 @@ void FreeFn(void* address, void* context) {
   MUSTTAIL return allocator_dispatch.next->free_function(address, context);
 }
 
-void FreeDefiniteSizeFn(void* address, size_t size, void* context) {
+void FreeWithSizeFn(void* address, size_t size, void* context) {
   if (sampling_state.Sample()) [[unlikely]] {
     if (Quarantine(address)) [[likely]] {
       return;
     }
   }
-  MUSTTAIL return allocator_dispatch.next->free_definite_size_function(
+  MUSTTAIL return allocator_dispatch.next->free_with_size_function(
       address, size, context);
 }
 
+void FreeWithAlignmentFn(void* address, size_t alignment, void* context) {
+  if (sampling_state.Sample()) [[unlikely]] {
+    if (Quarantine(address)) [[likely]] {
+      return;
+    }
+  }
+  MUSTTAIL return allocator_dispatch.next->free_with_alignment_function(
+      address, alignment, context);
+}
+
+void FreeWithSizeAndAlignmentFn(void* address,
+                                size_t size,
+                                size_t alignment,
+                                void* context) {
+  if (sampling_state.Sample()) [[unlikely]] {
+    if (Quarantine(address)) [[likely]] {
+      return;
+    }
+  }
+  MUSTTAIL return allocator_dispatch.next
+      ->free_with_size_and_alignment_function(address, size, alignment,
+                                              context);
+}
+
 AllocatorDispatch allocator_dispatch = {
     nullptr,  // alloc_function
     nullptr,  // alloc_unchecked_function
@@ -235,17 +259,19 @@ AllocatorDispatch allocator_dispatch = {
     nullptr,  // alloc_aligned_function
     // realloc doesn't always deallocate memory, so the Extreme LUD doesn't
     // support realloc.
-    nullptr,  // realloc_function
+    nullptr,                     // realloc_function
-    nullptr,  // realloc_unchecked_function
+    nullptr,                     // realloc_unchecked_function
-    FreeFn,   // free_function
+    FreeFn,                      // free_function
-    nullptr,  // get_size_estimate_function
+    FreeWithSizeFn,              // free_with_size_function
-    nullptr,  // good_size_function
+    FreeWithAlignmentFn,         // free_with_alignment_function
-    nullptr,  // claimed_address_function
+    FreeWithSizeAndAlignmentFn,  // free_with_size_and_alignment_function
-    nullptr,  // batch_malloc_function
+    nullptr,                     // get_size_estimate_function
+    nullptr,                     // good_size_function
+    nullptr,                     // claimed_address_function
+    nullptr,                     // batch_malloc_function
     // batch_free is rarely used, so the Extreme LUD doesn't support batch_free
     // (at least for now).
-    nullptr,             // batch_free_function
+    nullptr,  // batch_free_function
-    FreeDefiniteSizeFn,  // free_definite_size_function
     // try_free_default is rarely used, so the Extreme LUD doesn't support
     // try_free_default (at least for now).
     nullptr,  // try_free_default_function

components/gwp_asan/client/lightweight_detector/malloc_shims.cc

@@ -62,16 +62,40 @@ void FreeFn(void* address, void* context) {
   MUSTTAIL return g_allocator_dispatch.next->free_function(address, context);
 }
 
-void FreeDefiniteSizeFn(void* address, size_t size, void* context) {
+void FreeWithSizeFn(void* address, size_t size, void* context) {
   if (MaybeQuarantine(address, size, context,
-                      FreeFunctionKind::kFreeDefiniteSize)) {
+                      FreeFunctionKind::kFreeWithSize)) {
     return;
   }
 
-  MUSTTAIL return g_allocator_dispatch.next->free_definite_size_function(
+  MUSTTAIL return g_allocator_dispatch.next->free_with_size_function(
       address, size, context);
 }
 
+void FreeWithAlignmentFn(void* address, size_t alignment, void* context) {
+  if (MaybeQuarantine(address, std::nullopt, context,
+                      FreeFunctionKind::kFreeWithAlignment)) {
+    return;
+  }
+
+  MUSTTAIL return g_allocator_dispatch.next->free_with_alignment_function(
+      address, alignment, context);
+}
+
+void FreeWithSizeAndAlignmentFn(void* address,
+                                size_t size,
+                                size_t alignment,
+                                void* context) {
+  if (MaybeQuarantine(address, size, context,
+                      FreeFunctionKind::kFreeWithSizeAndAlignment)) {
+    return;
+  }
+
+  MUSTTAIL return g_allocator_dispatch.next
+      ->free_with_size_and_alignment_function(address, size, alignment,
+                                              context);
+}
+
 void TryFreeDefaultFn(void* address, void* context) {
   if (MaybeQuarantine(address, std::nullopt, context,
                       FreeFunctionKind::kTryFreeDefault)) {
@@ -93,26 +117,28 @@ static void AlignedFreeFn(void* address, void* context) {
 }
 
 AllocatorDispatch g_allocator_dispatch = {
-    nullptr,             // alloc_function
+    nullptr,                     // alloc_function
-    nullptr,             // alloc_unchecked_function
+    nullptr,                     // alloc_unchecked_function
-    nullptr,             // alloc_zero_initialized_function
+    nullptr,                     // alloc_zero_initialized_function
-    nullptr,             // alloc_aligned_function
+    nullptr,                     // alloc_aligned_function
-    nullptr,             // realloc_function
+    nullptr,                     // realloc_function
-    nullptr,             // realloc_unchecked_function
+    nullptr,                     // realloc_unchecked_function
-    FreeFn,              // free_function
+    FreeFn,                      // free_function
-    nullptr,             // get_size_estimate_function
+    FreeWithSizeFn,              // free_with_size_function
-    nullptr,             // good_size_function
+    FreeWithAlignmentFn,         // free_with_alignment_function
-    nullptr,             // claimed_address_function
+    FreeWithSizeAndAlignmentFn,  // free_with_size_and_alignment_function
-    nullptr,             // batch_malloc_function
+    nullptr,                     // get_size_estimate_function
-    nullptr,             // batch_free_function
+    nullptr,                     // good_size_function
-    FreeDefiniteSizeFn,  // free_definite_size_function
+    nullptr,                     // claimed_address_function
-    TryFreeDefaultFn,    // try_free_default_function
+    nullptr,                     // batch_malloc_function
-    nullptr,             // aligned_malloc_function
+    nullptr,                     // batch_free_function
-    nullptr,             // aligned_malloc_unchecked_function
+    TryFreeDefaultFn,            // try_free_default_function
-    nullptr,             // aligned_realloc_function
+    nullptr,                     // aligned_malloc_function
-    nullptr,             // aligned_realloc_unchecked_function
+    nullptr,                     // aligned_malloc_unchecked_function
-    AlignedFreeFn,       // aligned_free_function
+    nullptr,                     // aligned_realloc_function
-    nullptr              // next
+    nullptr,                     // aligned_realloc_unchecked_function
+    AlignedFreeFn,               // aligned_free_function
+    nullptr                      // next
 };
 
 }  // namespace
@@ -145,9 +171,19 @@ void FinishFree(const AllocationInfo& allocation) {
     case FreeFunctionKind::kFree:
       next->free_function(allocation.address, context);
       break;
-    case FreeFunctionKind::kFreeDefiniteSize:
+    case FreeFunctionKind::kFreeWithSize:
-      next->free_definite_size_function(allocation.address, allocation.size,
+      next->free_with_size_function(allocation.address, allocation.size,
-                                        context);
+                                    context);
+      break;
+    case FreeFunctionKind::kFreeWithAlignment:
+      // TODO(crbug.com/412358843): Memory and forward alignment information.
+      next->free_function(allocation.address, context);
+      break;
+    case FreeFunctionKind::kFreeWithSizeAndAlignment:
+      // TODO(crbug.com/412358843): Similar to above, forward alignment
+      // information. We shall not forward size information here because it can
+      // confuse an allocator by alignment mismatch.
+      next->free_function(allocation.address, context);
       break;
     case FreeFunctionKind::kTryFreeDefault:
       next->try_free_default_function(allocation.address, context);

components/gwp_asan/client/lightweight_detector/malloc_shims.h

@@ -19,7 +19,9 @@ namespace gwp_asan::internal::lud {
 enum class FreeFunctionKind : uint8_t {
   kUnknown,
   kFree,
-  kFreeDefiniteSize,
+  kFreeWithSize,
+  kFreeWithAlignment,
+  kFreeWithSizeAndAlignment,
   kTryFreeDefault,
   kAlignedFree,
 };

components/gwp_asan/client/sampling_malloc_shims.cc

@@ -160,6 +160,44 @@ void FreeFn(void* address, void* context) {
   g_allocator_dispatch.next->free_function(address, context);
 }
 
+void FreeWithSizeFn(void* address, size_t size, void* context) {
+  if (gpa->PointerIsMine(address)) [[unlikely]] {
+    // TODO(vtsyrklevich): Perform this check in GuardedPageAllocator and report
+    // failed checks using the same pipeline.
+    CHECK_EQ(size, gpa->GetRequestedSize(address));
+    gpa->Deallocate(address);
+    return;
+  }
+
+  g_allocator_dispatch.next->free_with_size_function(address, size, context);
+}
+
+void FreeWithAlignmentFn(void* address, size_t alignment, void* context) {
+  if (gpa->PointerIsMine(address)) [[unlikely]] {
+    gpa->Deallocate(address);
+    return;
+  }
+
+  g_allocator_dispatch.next->free_with_alignment_function(address, alignment,
+                                                          context);
+}
+
+void FreeWithSizeAndAlignmentFn(void* address,
+                                size_t size,
+                                size_t alignment,
+                                void* context) {
+  if (gpa->PointerIsMine(address)) [[unlikely]] {
+    // TODO(vtsyrklevich): Perform this check in GuardedPageAllocator and report
+    // failed checks using the same pipeline.
+    CHECK_EQ(size, gpa->GetRequestedSize(address));
+    gpa->Deallocate(address);
+    return;
+  }
+
+  g_allocator_dispatch.next->free_with_size_and_alignment_function(
+      address, size, alignment, context);
+}
+
 size_t GetSizeEstimateFn(void* address, void* context) {
   if (gpa->PointerIsMine(address)) [[unlikely]] {
     return gpa->GetRequestedSize(address);
@@ -212,19 +250,6 @@ void BatchFreeFn(void** to_be_freed, unsigned num_to_be_freed, void* context) {
                                                  context);
 }
 
-void FreeDefiniteSizeFn(void* address, size_t size, void* context) {
-  if (gpa->PointerIsMine(address)) [[unlikely]] {
-    // TODO(vtsyrklevich): Perform this check in GuardedPageAllocator and report
-    // failed checks using the same pipeline.
-    CHECK_EQ(size, gpa->GetRequestedSize(address));
-    gpa->Deallocate(address);
-    return;
-  }
-
-  g_allocator_dispatch.next->free_definite_size_function(address, size,
-                                                         context);
-}
-
 void TryFreeDefaultFn(void* address, void* context) {
   if (gpa->PointerIsMine(address)) [[unlikely]] {
     gpa->Deallocate(address);
@@ -335,12 +360,14 @@ AllocatorDispatch g_allocator_dispatch = {
     &ReallocFn,
     &ReallocUncheckedFn,
     &FreeFn,
+    &FreeWithSizeFn,
+    &FreeWithAlignmentFn,
+    &FreeWithSizeAndAlignmentFn,
     &GetSizeEstimateFn,
     &GoodSizeFn,
     &ClaimedAddressFn,
     &BatchMallocFn,
     &BatchFreeFn,
-    &FreeDefiniteSizeFn,
     &TryFreeDefaultFn,
     &AlignedMallocFn,
     &AlignedMallocUncheckedFn,