648db22b |
1 | /* |
2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
3 | * All rights reserved. |
4 | * |
5 | * This source code is licensed under both the BSD-style license (found in the |
6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
7 | * in the COPYING file in the root directory of this source tree). |
8 | * You may select, at your option, one of the above-listed licenses. |
9 | */ |
10 | |
11 | /** |
12 | * This fuzz target attempts to decompress the fuzzed data with the simple |
13 | * decompression function to ensure the decompressor never crashes. |
14 | */ |
15 | |
16 | #define ZSTD_STATIC_LINKING_ONLY |
17 | |
18 | #include <stddef.h> |
19 | #include <stdlib.h> |
20 | #include <stdio.h> |
21 | #include "fuzz_helpers.h" |
22 | #include "zstd.h" |
23 | #include "fuzz_data_producer.h" |
24 | |
25 | static ZSTD_DStream *dstream = NULL; |
26 | uint32_t seed; |
27 | |
28 | static ZSTD_outBuffer makeOutBuffer(FUZZ_dataProducer_t *producer, void* buf, size_t bufSize) |
29 | { |
30 | ZSTD_outBuffer buffer = { buf, 0, 0 }; |
31 | |
32 | if (FUZZ_dataProducer_empty(producer)) { |
33 | buffer.size = bufSize; |
34 | } else { |
35 | buffer.size = (FUZZ_dataProducer_uint32Range(producer, 0, bufSize)); |
36 | } |
37 | FUZZ_ASSERT(buffer.size <= bufSize); |
38 | |
39 | if (buffer.size == 0) { |
40 | buffer.dst = NULL; |
41 | } |
42 | |
43 | return buffer; |
44 | } |
45 | |
46 | static ZSTD_inBuffer makeInBuffer(const uint8_t **src, size_t *size, |
47 | FUZZ_dataProducer_t *producer) |
48 | { |
49 | ZSTD_inBuffer buffer = { *src, 0, 0 }; |
50 | |
51 | FUZZ_ASSERT(*size > 0); |
52 | if (FUZZ_dataProducer_empty(producer)) { |
53 | buffer.size = *size; |
54 | } else { |
55 | buffer.size = (FUZZ_dataProducer_uint32Range(producer, 0, *size)); |
56 | } |
57 | FUZZ_ASSERT(buffer.size <= *size); |
58 | *src += buffer.size; |
59 | *size -= buffer.size; |
60 | |
61 | if (buffer.size == 0) { |
62 | buffer.src = NULL; |
63 | } |
64 | |
65 | return buffer; |
66 | } |
67 | |
68 | int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size) |
69 | { |
70 | /* Give a random portion of src data to the producer, to use for |
71 | parameter generation. The rest will be used for (de)compression */ |
72 | FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(src, size); |
73 | int stableOutBuffer; |
74 | ZSTD_outBuffer out; |
75 | void* buf; |
76 | size_t bufSize; |
77 | size = FUZZ_dataProducer_reserveDataPrefix(producer); |
78 | bufSize = MAX(10 * size, ZSTD_BLOCKSIZE_MAX); |
79 | |
80 | /* Allocate all buffers and contexts if not already allocated */ |
81 | buf = FUZZ_malloc(bufSize); |
82 | |
83 | if (!dstream) { |
84 | dstream = ZSTD_createDStream(); |
85 | FUZZ_ASSERT(dstream); |
86 | } else { |
87 | FUZZ_ZASSERT(ZSTD_DCtx_reset(dstream, ZSTD_reset_session_only)); |
88 | } |
89 | |
90 | stableOutBuffer = FUZZ_dataProducer_uint32Range(producer, 0, 10) == 5; |
91 | if (stableOutBuffer) { |
92 | FUZZ_ZASSERT(ZSTD_DCtx_setParameter(dstream, ZSTD_d_stableOutBuffer, 1)); |
93 | out.dst = buf; |
94 | out.size = bufSize; |
95 | out.pos = 0; |
96 | } else { |
97 | out = makeOutBuffer(producer, buf, bufSize); |
98 | } |
99 | |
100 | while (size > 0) { |
101 | ZSTD_inBuffer in = makeInBuffer(&src, &size, producer); |
102 | do { |
103 | size_t const rc = ZSTD_decompressStream(dstream, &out, &in); |
104 | if (ZSTD_isError(rc)) goto error; |
105 | if (out.pos == out.size) { |
106 | if (stableOutBuffer) goto error; |
107 | out = makeOutBuffer(producer, buf, bufSize); |
108 | } |
109 | } while (in.pos != in.size); |
110 | } |
111 | |
112 | error: |
113 | #ifndef STATEFUL_FUZZING |
114 | ZSTD_freeDStream(dstream); dstream = NULL; |
115 | #endif |
116 | FUZZ_dataProducer_free(producer); |
117 | free(buf); |
118 | return 0; |
119 | } |