lz4/ossfuzz/compress_fuzzer.c
Nick Terrell 3c40db8d25 [ossfuzz] Improve the fuzzers
* Run more decompression variants
* Round trip the compression fuzzer and do partial decompression as well
* Add a compression fuzzer that compresses into a smaller output buffer
  and test the destSize variant

These fuzzers caught 2 bugs that were fixed in the previous commit.
* Input buffer over-read in partial decompress
* Partial decompress fails if output size is 0
2019-07-15 12:22:04 -07:00

52 lines
1.7 KiB
C

/**
* This fuzz target attempts to compress the fuzzed data with the simple
* compression function with an output buffer that may be too small to
* ensure that the compressor never crashes.
*/
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "fuzz_helpers.h"
#include "lz4.h"
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
{
uint32_t seed = FUZZ_seed(&data, &size);
size_t const dstCapacity = FUZZ_rand32(&seed, 0, LZ4_compressBound(size));
char* const dst = (char*)malloc(dstCapacity);
char* const rt = (char*)malloc(size);
FUZZ_ASSERT(dst);
FUZZ_ASSERT(rt);
/* If compression succeeds it must round trip correctly. */
{
int const dstSize = LZ4_compress_default((const char*)data, dst,
size, dstCapacity);
if (dstSize > 0) {
int const rtSize = LZ4_decompress_safe(dst, rt, dstSize, size);
FUZZ_ASSERT_MSG(rtSize == size, "Incorrect regenerated size");
FUZZ_ASSERT_MSG(!memcmp(data, rt, size), "Corruption!");
}
}
if (dstCapacity > 0) {
/* Compression succeeds and must round trip correctly. */
int compressedSize = size;
int const dstSize = LZ4_compress_destSize((const char*)data, dst,
&compressedSize, dstCapacity);
FUZZ_ASSERT(dstSize > 0);
int const rtSize = LZ4_decompress_safe(dst, rt, dstSize, size);
FUZZ_ASSERT_MSG(rtSize == compressedSize, "Incorrect regenerated size");
FUZZ_ASSERT_MSG(!memcmp(data, rt, compressedSize), "Corruption!");
}
free(dst);
free(rt);
return 0;
}