1 /**
2 * This fuzz target attempts to decompress the fuzzed data with the simple
3 * decompression function to ensure the decompressor never crashes.
4 */
5
6 #include <stddef.h>
7 #include <stdint.h>
8 #include <stdlib.h>
9 #include <string.h>
10
11 #include "fuzz_helpers.h"
12 #include "fuzz_data_producer.h"
13 #include "lz4.h"
14 #define LZ4F_STATIC_LINKING_ONLY
15 #include "lz4frame.h"
16 #include "lz4_helpers.h"
17
decompress(LZ4F_dctx * dctx,void * dst,size_t dstCapacity,const void * src,size_t srcSize,const void * dict,size_t dictSize,const LZ4F_decompressOptions_t * opts)18 static void decompress(LZ4F_dctx* dctx, void* dst, size_t dstCapacity,
19 const void* src, size_t srcSize,
20 const void* dict, size_t dictSize,
21 const LZ4F_decompressOptions_t* opts)
22 {
23 LZ4F_resetDecompressionContext(dctx);
24 if (dictSize == 0)
25 LZ4F_decompress(dctx, dst, &dstCapacity, src, &srcSize, opts);
26 else
27 LZ4F_decompress_usingDict(dctx, dst, &dstCapacity, src, &srcSize,
28 dict, dictSize, opts);
29 }
30
LLVMFuzzerTestOneInput(const uint8_t * data,size_t size)31 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
32 {
33 FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(data, size);
34 size_t const dstCapacitySeed = FUZZ_dataProducer_retrieve32(producer);
35 size_t const dictSizeSeed = FUZZ_dataProducer_retrieve32(producer);
36 size = FUZZ_dataProducer_remainingBytes(producer);
37
38 size_t const dstCapacity = FUZZ_getRange_from_uint32(
39 dstCapacitySeed, 0, 4 * size);
40 size_t const largeDictSize = 64 * 1024;
41 size_t const dictSize = FUZZ_getRange_from_uint32(
42 dictSizeSeed, 0, largeDictSize);
43
44 char* const dst = (char*)malloc(dstCapacity);
45 char* const dict = (char*)malloc(dictSize);
46 LZ4F_decompressOptions_t opts;
47 LZ4F_dctx* dctx;
48 LZ4F_createDecompressionContext(&dctx, LZ4F_VERSION);
49
50 FUZZ_ASSERT(dctx);
51 FUZZ_ASSERT(dst);
52 FUZZ_ASSERT(dict);
53
54 /* Prepare the dictionary. The data doesn't matter for decompression. */
55 memset(dict, 0, dictSize);
56
57
58 /* Decompress using multiple configurations. */
59 memset(&opts, 0, sizeof(opts));
60 opts.stableDst = 0;
61 decompress(dctx, dst, dstCapacity, data, size, NULL, 0, &opts);
62 opts.stableDst = 1;
63 decompress(dctx, dst, dstCapacity, data, size, NULL, 0, &opts);
64 opts.stableDst = 0;
65 decompress(dctx, dst, dstCapacity, data, size, dict, dictSize, &opts);
66 opts.stableDst = 1;
67 decompress(dctx, dst, dstCapacity, data, size, dict, dictSize, &opts);
68
69 LZ4F_freeDecompressionContext(dctx);
70 free(dst);
71 free(dict);
72 FUZZ_dataProducer_free(producer);
73
74 return 0;
75 }
76