1 // Copyright 2020 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include <stddef.h>
16 #include <stdint.h>
17 #include <unistd.h>
18 #include <assert.h>
19 #include <sys/syscall.h>
20 #include <linux/memfd.h>
21 #include <fuzzer/FuzzedDataProvider.h>
22
23 #include "ext2fs/ext2fs.h"
24
LLVMFuzzerTestOneInput(const uint8_t * data,size_t size)25 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
26
27 enum FuzzerType {
28 ext2fsReadBlockBitmap,
29 ext2fsReadInodeBitmap,
30 kMaxValue = ext2fsReadInodeBitmap
31 };
32
33 FuzzedDataProvider stream(data, size);
34 const FuzzerType f = stream.ConsumeEnum<FuzzerType>();
35 static const char* fname = "/tmp/ext2_test_file";
36
37 // Write our data to a temp file.
38 int fd = syscall(SYS_memfd_create, fname, 0);
39 std::vector<char> buffer = stream.ConsumeRemainingBytes<char>();
40 write(fd, buffer.data(), buffer.size());
41 close(fd);
42
43 ext2_filsys fs;
44 errcode_t retval = ext2fs_open(
45 fname,
46 0, 0, 0,
47 unix_io_manager,
48 &fs);
49
50 if (!retval) {
51 switch (f) {
52 case ext2fsReadBlockBitmap: {
53 ext2fs_read_block_bitmap(fs);
54 break;
55 }
56 case ext2fsReadInodeBitmap: {
57 ext2fs_read_inode_bitmap(fs);
58 break;
59 }
60 default: {
61 assert(false);
62 }
63 }
64 ext2fs_close(fs);
65 }
66
67 return 0;
68 }
69