diff --git a/libc/malloc_debug/TrackData.cpp b/libc/malloc_debug/TrackData.cpp
index e5260a9..c9828d0 100644
--- a/libc/malloc_debug/TrackData.cpp
+++ b/libc/malloc_debug/TrackData.cpp
@@ -44,7 +44,7 @@
 #include "malloc_debug.h"
 #include "TrackData.h"
 
-void TrackData::GetList(std::vector<Header*>* list) {
+void TrackData::GetList(std::vector<const Header*>* list) {
   ScopedDisableDebugCalls disable;
 
   for (const auto& header : headers_) {
@@ -52,13 +52,13 @@
   }
 
   // Sort by the size of the allocation.
-  std::sort(list->begin(), list->end(), [](Header* a, Header* b) {
+  std::sort(list->begin(), list->end(), [](const Header* a, const Header* b) {
     if (a->size == b->size) return a < b;
     return a->size > b->size;
   });
 }
 
-void TrackData::Add(Header* header, bool backtrace_found) {
+void TrackData::Add(const Header* header, bool backtrace_found) {
   ScopedDisableDebugCalls disable;
 
   pthread_mutex_lock(&mutex_);
@@ -69,7 +69,7 @@
   pthread_mutex_unlock(&mutex_);
 }
 
-void TrackData::Remove(Header* header, bool backtrace_found) {
+void TrackData::Remove(const Header* header, bool backtrace_found) {
   ScopedDisableDebugCalls disable;
 
   pthread_mutex_lock(&mutex_);
@@ -80,10 +80,19 @@
   pthread_mutex_unlock(&mutex_);
 }
 
+bool TrackData::Contains(const Header* header) {
+  ScopedDisableDebugCalls disable;
+
+  pthread_mutex_lock(&mutex_);
+  bool found = headers_.count(header);
+  pthread_mutex_unlock(&mutex_);
+  return found;
+}
+
 void TrackData::DisplayLeaks(DebugData& debug) {
   ScopedDisableDebugCalls disable;
 
-  std::vector<Header*> list;
+  std::vector<const Header*> list;
   GetList(&list);
 
   size_t track_count = 0;
@@ -117,7 +126,7 @@
   }
   *overall_size = *info_size * total_backtrace_allocs_;
 
-  std::vector<Header*> list;
+  std::vector<const Header*> list;
   GetList(&list);
 
   uint8_t* data = *info;
diff --git a/libc/malloc_debug/TrackData.h b/libc/malloc_debug/TrackData.h
index dcf0ede..1234316 100644
--- a/libc/malloc_debug/TrackData.h
+++ b/libc/malloc_debug/TrackData.h
@@ -47,11 +47,13 @@
   TrackData() = default;
   virtual ~TrackData() = default;
 
-  void GetList(std::vector<Header*>* list);
+  void GetList(std::vector<const Header*>* list);
 
-  void Add(Header* header, bool backtrace_found);
+  void Add(const Header* header, bool backtrace_found);
 
-  void Remove(Header* header, bool backtrace_found);
+  void Remove(const Header* header, bool backtrace_found);
+
+  bool Contains(const Header *header);
 
   void GetInfo(DebugData& debug, uint8_t** info, size_t* overall_size,
                size_t* info_size, size_t* total_memory, size_t* backtrace_size);
@@ -64,7 +66,7 @@
 
  private:
   pthread_mutex_t mutex_ = PTHREAD_MUTEX_INITIALIZER;
-  std::unordered_set<Header*> headers_;
+  std::unordered_set<const Header*> headers_;
   size_t total_backtrace_allocs_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(TrackData);
diff --git a/libc/malloc_debug/exported32.map b/libc/malloc_debug/exported32.map
index aef8818..8f994f1 100644
--- a/libc/malloc_debug/exported32.map
+++ b/libc/malloc_debug/exported32.map
@@ -6,8 +6,11 @@
     debug_free_malloc_leak_info;
     debug_get_malloc_leak_info;
     debug_initialize;
+    debug_iterate;
     debug_mallinfo;
     debug_malloc;
+    debug_malloc_disable;
+    debug_malloc_enable;
     debug_malloc_usable_size;
     debug_memalign;
     debug_posix_memalign;
diff --git a/libc/malloc_debug/exported64.map b/libc/malloc_debug/exported64.map
index 70fd581..8c47449 100644
--- a/libc/malloc_debug/exported64.map
+++ b/libc/malloc_debug/exported64.map
@@ -6,8 +6,11 @@
     debug_free_malloc_leak_info;
     debug_get_malloc_leak_info;
     debug_initialize;
+    debug_iterate;
     debug_mallinfo;
     debug_malloc;
+    debug_malloc_disable;
+    debug_malloc_enable;
     debug_malloc_usable_size;
     debug_memalign;
     debug_posix_memalign;
diff --git a/libc/malloc_debug/malloc_debug.cpp b/libc/malloc_debug/malloc_debug.cpp
index dcc6048..5b6e415 100644
--- a/libc/malloc_debug/malloc_debug.cpp
+++ b/libc/malloc_debug/malloc_debug.cpp
@@ -76,6 +76,10 @@
 void* debug_calloc(size_t nmemb, size_t bytes);
 struct mallinfo debug_mallinfo();
 int debug_posix_memalign(void** memptr, size_t alignment, size_t size);
+int debug_iterate(uintptr_t base, size_t size,
+    void (*callback)(uintptr_t base, size_t size, void* arg), void* arg);
+void debug_malloc_disable();
+void debug_malloc_enable();
 
 #if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
 void* debug_pvalloc(size_t bytes);
@@ -569,6 +573,49 @@
   return (*memptr != nullptr) ? 0 : ENOMEM;
 }
 
+int debug_iterate(uintptr_t base, size_t size,
+    void (*callback)(uintptr_t base, size_t size, void* arg), void* arg) {
+  // Can't allocate, malloc is disabled
+  // Manual capture of the arguments to pass to the lambda below as void* arg
+  struct iterate_ctx {
+    decltype(callback) callback;
+    decltype(arg) arg;
+  } ctx = { callback, arg };
+
+  return g_dispatch->iterate(base, size,
+      [](uintptr_t base, size_t size, void* arg) {
+        const iterate_ctx* ctx = reinterpret_cast<iterate_ctx*>(arg);
+        const void* pointer = reinterpret_cast<void*>(base);
+        if (g_debug->need_header()) {
+          const Header* header = reinterpret_cast<const Header*>(pointer);
+          if (g_debug->config().options & TRACK_ALLOCS) {
+            if (g_debug->track->Contains(header)) {
+              // Return just the body of the allocation if we're sure the header exists
+              ctx->callback(reinterpret_cast<uintptr_t>(g_debug->GetPointer(header)),
+                  header->real_size(), ctx->arg);
+              return;
+            }
+          }
+        }
+        // Fall back to returning the whole allocation
+        ctx->callback(base, size, ctx->arg);
+      }, &ctx);
+}
+
+void debug_malloc_disable() {
+  g_dispatch->malloc_disable();
+  if (g_debug->track) {
+    g_debug->track->PrepareFork();
+  }
+}
+
+void debug_malloc_enable() {
+  if (g_debug->track) {
+    g_debug->track->PostForkParent();
+  }
+  g_dispatch->malloc_enable();
+}
+
 #if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
 void* debug_pvalloc(size_t bytes) {
   if (DebugCallsDisabled()) {
diff --git a/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
index b316e8a..28729e8 100644
--- a/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
+++ b/libc/malloc_debug/tests/malloc_debug_unit_tests.cpp
@@ -121,6 +121,9 @@
 #if defined(HAVE_DEPRECATED_MALLOC_FUNCS)
   nullptr,
 #endif
+  nullptr,
+  nullptr,
+  nullptr,
 };
 
 void VerifyAllocCalls() {