lz4/ossfuzz/decompress_fuzzer.c

64 lines
2.3 KiB
C

/**
* This fuzz target attempts to decompress the fuzzed data with the simple
* decompression function to ensure the decompressor never crashes.
*/
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "fuzz_helpers.h"
#include "fuzz_data_producer.h"
#include "lz4.h"
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(data, size);
size_t const dstCapacity = FUZZ_dataProducer_uint32(
producer, 0, 4 * size);
size_t const smallDictSize = size + 1;
size_t const largeDictSize = 64 * 1024 - 1;
size_t const dictSize = MAX(smallDictSize, largeDictSize);
char* const dst = (char*)malloc(dstCapacity);
char* const dict = (char*)malloc(dictSize + size);
char* const largeDict = dict;
char* const dataAfterDict = dict + dictSize;
char* const smallDict = dataAfterDict - smallDictSize;
/* Restrict to remaining data from producer */
size = FUZZ_dataProducer_remainingBytes(producer);
FUZZ_ASSERT(dst);
FUZZ_ASSERT(dict);
/* Prepare the dictionary. The data doesn't matter for decompression. */
memset(dict, 0, dictSize);
memcpy(dataAfterDict, data, size);
/* Decompress using each possible dictionary configuration. */
/* No dictionary. */
LZ4_decompress_safe_usingDict((char const*)data, dst, size,
dstCapacity, NULL, 0);
/* Small external dictonary. */
LZ4_decompress_safe_usingDict((char const*)data, dst, size,
dstCapacity, smallDict, smallDictSize);
/* Large external dictionary. */
LZ4_decompress_safe_usingDict((char const*)data, dst, size,
dstCapacity, largeDict, largeDictSize);
/* Small prefix. */
LZ4_decompress_safe_usingDict((char const*)dataAfterDict, dst, size,
dstCapacity, smallDict, smallDictSize);
/* Large prefix. */
LZ4_decompress_safe_usingDict((char const*)data, dst, size,
dstCapacity, largeDict, largeDictSize);
/* Partial decompression. */
LZ4_decompress_safe_partial((char const*)data, dst, size,
dstCapacity, dstCapacity);
free(dst);
free(dict);
FUZZ_dataProducer_free(producer);
return 0;
}