1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #pragma once
30 
31 #include <stdbool.h>
32 #include <stdint.h>
33 
34 // Structures for android_mallopt.
35 
36 typedef struct {
37   // Pointer to the buffer allocated by a call to M_GET_MALLOC_LEAK_INFO.
38   uint8_t* buffer;
39   // The size of the "info" buffer.
40   size_t overall_size;
41   // The size of a single entry.
42   size_t info_size;
43   // The sum of all allocations that have been tracked. Does not include
44   // any heap overhead.
45   size_t total_memory;
46   // The maximum number of backtrace entries.
47   size_t backtrace_size;
48 } android_mallopt_leak_info_t;
49 
50 // Opcodes for android_mallopt.
51 
52 enum {
53   // Marks the calling process as a profileable zygote child, possibly
54   // initializing profiling infrastructure.
55   M_INIT_ZYGOTE_CHILD_PROFILING = 1,
56 #define M_INIT_ZYGOTE_CHILD_PROFILING M_INIT_ZYGOTE_CHILD_PROFILING
57   M_RESET_HOOKS = 2,
58 #define M_RESET_HOOKS M_RESET_HOOKS
59   // Set an upper bound on the total size in bytes of all allocations made
60   // using the memory allocation APIs.
61   //   arg = size_t*
62   //   arg_size = sizeof(size_t)
63   M_SET_ALLOCATION_LIMIT_BYTES = 3,
64 #define M_SET_ALLOCATION_LIMIT_BYTES M_SET_ALLOCATION_LIMIT_BYTES
65   // Called after the zygote forks to indicate this is a child.
66   M_SET_ZYGOTE_CHILD = 4,
67 #define M_SET_ZYGOTE_CHILD M_SET_ZYGOTE_CHILD
68 
69   // Options to dump backtraces of allocations. These options only
70   // work when malloc debug has been enabled.
71 
72   // Writes the backtrace information of all current allocations to a file.
73   // NOTE: arg_size has to be sizeof(FILE*) because FILE is an opaque type.
74   //   arg = FILE*
75   //   arg_size = sizeof(FILE*)
76   M_WRITE_MALLOC_LEAK_INFO_TO_FILE = 5,
77 #define M_WRITE_MALLOC_LEAK_INFO_TO_FILE M_WRITE_MALLOC_LEAK_INFO_TO_FILE
78   // Get information about the backtraces of all
79   //   arg = android_mallopt_leak_info_t*
80   //   arg_size = sizeof(android_mallopt_leak_info_t)
81   M_GET_MALLOC_LEAK_INFO = 6,
82 #define M_GET_MALLOC_LEAK_INFO M_GET_MALLOC_LEAK_INFO
83   // Free the memory allocated and returned by M_GET_MALLOC_LEAK_INFO.
84   //   arg = android_mallopt_leak_info_t*
85   //   arg_size = sizeof(android_mallopt_leak_info_t)
86   M_FREE_MALLOC_LEAK_INFO = 7,
87 #define M_FREE_MALLOC_LEAK_INFO M_FREE_MALLOC_LEAK_INFO
88   // Change the heap tagging state. The program must be single threaded at the point when the
89   // android_mallopt function is called.
90   //   arg = HeapTaggingLevel*
91   //   arg_size = sizeof(HeapTaggingLevel)
92   M_SET_HEAP_TAGGING_LEVEL = 8,
93 #define M_SET_HEAP_TAGGING_LEVEL M_SET_HEAP_TAGGING_LEVEL
94   // Query whether the current process is considered to be profileable by the
95   // Android platform. Result is assigned to the arg pointer's destination.
96   //   arg = bool*
97   //   arg_size = sizeof(bool)
98   M_GET_PROCESS_PROFILEABLE = 9,
99 #define M_GET_PROCESS_PROFILEABLE M_GET_PROCESS_PROFILEABLE
100   // Maybe enable GWP-ASan. Set *arg to force GWP-ASan to be turned on,
101   // otherwise this mallopt() will internally decide whether to sample the
102   // process. The program must be single threaded at the point when the
103   // android_mallopt function is called.
104   //   arg = bool*
105   //   arg_size = sizeof(bool)
106   M_INITIALIZE_GWP_ASAN = 10,
107 #define M_INITIALIZE_GWP_ASAN M_INITIALIZE_GWP_ASAN
108 };
109 
110 enum HeapTaggingLevel {
111   // Disable heap tagging. The program must use prctl(PR_SET_TAGGED_ADDR_CTRL) to disable memory tag
112   // checks before disabling heap tagging. Heap tagging may not be re-enabled after being disabled.
113   M_HEAP_TAGGING_LEVEL_NONE = 0,
114   // Address-only tagging. Heap pointers have a non-zero tag in the most significant byte which is
115   // checked in free(). Memory accesses ignore the tag.
116   M_HEAP_TAGGING_LEVEL_TBI = 1,
117   // Enable heap tagging if supported, at a level appropriate for asynchronous memory tag checks.
118   M_HEAP_TAGGING_LEVEL_ASYNC = 2,
119   // Enable heap tagging if supported, at a level appropriate for synchronous memory tag checks.
120   M_HEAP_TAGGING_LEVEL_SYNC = 3,
121 };
122 
123 // Manipulates bionic-specific handling of memory allocation APIs such as
124 // malloc. Only for use by the Android platform itself.
125 //
126 // On success, returns true. On failure, returns false and sets errno.
127 extern "C" bool android_mallopt(int opcode, void* arg, size_t arg_size);
128