[MemInit] Remove old API, introduce new MemInit API.

Introduces new heap-zero-init API. We've realised that it's better to be
able to individually control MTE and heap zero-init. Having
heap-zero-init not be controllable without affecting MTE affects our
ability to turn off heap-zero-init in zygote-forked applications.

Bug: 135772972
Test: On FVP: atest -s localhost:5555 malloc#zero_init \
Test: malloc#disable_mte heap_tagging_level
Change-Id: I8c6722502733259934c699f4f1269eaf1641a09f

1 files changed, 39 insertions, 0 deletions

diff --git a/libc/bionic/heap_zero_init.cpp b/libc/bionic/heap_zero_init.cpp
new file mode 100644
index 000000000..f5a05e57b
--- /dev/null
+++ b/libc/bionic/heap_zero_init.cpp
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "heap_zero_init.h"
+
+extern "C" void scudo_malloc_set_zero_contents(int zero_contents);
+
+bool SetHeapZeroInitialize(bool zero_init __attribute__((__unused__))) {
+#ifdef USE_SCUDO
+  scudo_malloc_set_zero_contents(zero_init);
+  return true;
+#endif
+  return false;
+}