1 /*
2  * Copyright 2020 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 #include <fuzzer/FuzzedDataProvider.h>
17 #include "osi/include/compat.h"
18 
19 #define MAX_BUFFER_SIZE 4096
20 
LLVMFuzzerTestOneInput(const uint8_t * Data,size_t Size)21 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, size_t Size) {
22 // Our functions are only defined with __GLIBC__
23 #if __GLIBC__
24   // Init our wrapper
25   FuzzedDataProvider dataProvider(Data, Size);
26 
27   size_t buf_size =
28       dataProvider.ConsumeIntegralInRange<size_t>(0, MAX_BUFFER_SIZE);
29   if (buf_size == 0) {
30     return 0;
31   }
32 
33   // Set up our buffers
34   // NOTE: If the src buffer is not NULL-terminated, the strlcpy will
35   //       overread regardless of the len arg. Force null-term for now.
36   std::vector<char> bytes =
37       dataProvider.ConsumeBytesWithTerminator<char>(buf_size, '\0');
38   if (bytes.empty()) {
39     return 0;
40   }
41   buf_size = bytes.size();
42   void* dst_buf = malloc(buf_size);
43   if (dst_buf == nullptr) {
44     return 0;
45   }
46 
47   // Call the getId fn just to ensure things don't crash
48   gettid();
49 
50   // Copy, then concat
51   size_t len_to_cpy = dataProvider.ConsumeIntegralInRange<size_t>(0, buf_size);
52   strlcpy(reinterpret_cast<char*>(dst_buf),
53           reinterpret_cast<char*>(bytes.data()), len_to_cpy);
54   strlcat(reinterpret_cast<char*>(dst_buf),
55           reinterpret_cast<char*>(bytes.data()), len_to_cpy);
56 
57   // Clear out our dest buffer
58   free(dst_buf);
59 #endif
60 
61   return 0;
62 }
63