1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <sys/cdefs.h>
18 #include <unistd.h>
19
20 #include <functional>
21
22 #include "Binder.h"
23 #include "log.h"
24
25 __BEGIN_DECLS
26
27 // Weak undefined references to the symbols in libbinder and libhwbinder
28 // so that libmemunreachable can call them in processes that have them
29 // loaded without requiring libmemunreachable to have dependencies on them.
30 ssize_t __attribute__((weak)) getBinderKernelReferences(size_t, uintptr_t*);
31 ssize_t __attribute__((weak)) getHWBinderKernelReferences(size_t, uintptr_t*);
32
33 __END_DECLS
34
35 namespace android {
36
BinderReferencesToVector(allocator::vector<uintptr_t> & refs,std::function<ssize_t (size_t,uintptr_t *)> fn)37 static bool BinderReferencesToVector(allocator::vector<uintptr_t>& refs,
38 std::function<ssize_t(size_t, uintptr_t*)> fn) {
39 if (fn == nullptr) {
40 return true;
41 }
42
43 size_t size = refs.size();
44
45 do {
46 refs.resize(size);
47
48 ssize_t ret = fn(refs.size(), refs.data());
49 if (ret < 0) {
50 return false;
51 }
52
53 size = ret;
54 } while (size > refs.size());
55
56 refs.resize(size);
57 return true;
58 }
59
BinderReferences(allocator::vector<uintptr_t> & refs)60 bool BinderReferences(allocator::vector<uintptr_t>& refs) {
61 refs.clear();
62
63 allocator::vector<uintptr_t> binder_refs{refs.get_allocator()};
64 if (BinderReferencesToVector(refs, getBinderKernelReferences)) {
65 refs.insert(refs.end(), binder_refs.begin(), binder_refs.end());
66 } else {
67 MEM_ALOGE("getBinderKernelReferences failed");
68 }
69
70 allocator::vector<uintptr_t> hwbinder_refs{refs.get_allocator()};
71 if (BinderReferencesToVector(hwbinder_refs, getHWBinderKernelReferences)) {
72 refs.insert(refs.end(), hwbinder_refs.begin(), hwbinder_refs.end());
73 } else {
74 MEM_ALOGE("getHWBinderKernelReferences failed");
75 }
76
77 return true;
78 }
79
80 } // namespace android
81