--- /dev/null
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+/**
+ * This fuzz target performs a zstd round-trip test (compress & decompress),
+ * compares the result with the original, and calls abort() on corruption.
+ */
+
+#define ZSTD_STATIC_LINKING_ONLY
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "fuzz_helpers.h"
+#include "zstd_helpers.h"
+#include "fuzz_data_producer.h"
+#include "fuzz_third_party_seq_prod.h"
+
+static ZSTD_CCtx *cctx = NULL;
+static ZSTD_DCtx *dctx = NULL;
+
+static size_t getDecompressionMargin(void const* compressed, size_t cSize, size_t srcSize, int hasSmallBlocks)
+{
+ size_t margin = ZSTD_decompressionMargin(compressed, cSize);
+ if (!hasSmallBlocks) {
+ /* The macro should be correct in this case, but it may be smaller
+ * because of e.g. block splitting, so take the smaller of the two.
+ */
+ ZSTD_frameHeader zfh;
+ size_t marginM;
+ FUZZ_ZASSERT(ZSTD_getFrameHeader(&zfh, compressed, cSize));
+ marginM = ZSTD_DECOMPRESSION_MARGIN(srcSize, zfh.blockSizeMax);
+ if (marginM < margin)
+ margin = marginM;
+ }
+ return margin;
+}
+
+static size_t roundTripTest(void *result, size_t resultCapacity,
+ void *compressed, size_t compressedCapacity,
+ const void *src, size_t srcSize,
+ FUZZ_dataProducer_t *producer)
+{
+ size_t cSize;
+ size_t dSize;
+ int targetCBlockSize = 0;
+ if (FUZZ_dataProducer_uint32Range(producer, 0, 1)) {
+ size_t const remainingBytes = FUZZ_dataProducer_remainingBytes(producer);
+ FUZZ_setRandomParameters(cctx, srcSize, producer);
+ cSize = ZSTD_compress2(cctx, compressed, compressedCapacity, src, srcSize);
+ FUZZ_ZASSERT(cSize);
+ FUZZ_ZASSERT(ZSTD_CCtx_getParameter(cctx, ZSTD_c_targetCBlockSize, &targetCBlockSize));
+ // Compress a second time and check for determinism
+ {
+ size_t const cSize0 = cSize;
+ XXH64_hash_t const hash0 = XXH64(compressed, cSize, 0);
+ FUZZ_dataProducer_rollBack(producer, remainingBytes);
+ FUZZ_setRandomParameters(cctx, srcSize, producer);
+ cSize = ZSTD_compress2(cctx, compressed, compressedCapacity, src, srcSize);
+ FUZZ_ASSERT(cSize == cSize0);
+ FUZZ_ASSERT(XXH64(compressed, cSize, 0) == hash0);
+ }
+ } else {
+ int const cLevel = FUZZ_dataProducer_int32Range(producer, kMinClevel, kMaxClevel);
+ cSize = ZSTD_compressCCtx(
+ cctx, compressed, compressedCapacity, src, srcSize, cLevel);
+ FUZZ_ZASSERT(cSize);
+ // Compress a second time and check for determinism
+ {
+ size_t const cSize0 = cSize;
+ XXH64_hash_t const hash0 = XXH64(compressed, cSize, 0);
+ cSize = ZSTD_compressCCtx(
+ cctx, compressed, compressedCapacity, src, srcSize, cLevel);
+ FUZZ_ASSERT(cSize == cSize0);
+ FUZZ_ASSERT(XXH64(compressed, cSize, 0) == hash0);
+ }
+ }
+ dSize = ZSTD_decompressDCtx(dctx, result, resultCapacity, compressed, cSize);
+ FUZZ_ZASSERT(dSize);
+ FUZZ_ASSERT_MSG(dSize == srcSize, "Incorrect regenerated size");
+ FUZZ_ASSERT_MSG(!FUZZ_memcmp(src, result, dSize), "Corruption!");
+
+ {
+ size_t margin = getDecompressionMargin(compressed, cSize, srcSize, targetCBlockSize);
+ size_t const outputSize = srcSize + margin;
+ char* const output = (char*)FUZZ_malloc(outputSize);
+ char* const input = output + outputSize - cSize;
+ FUZZ_ASSERT(outputSize >= cSize);
+ memcpy(input, compressed, cSize);
+
+ dSize = ZSTD_decompressDCtx(dctx, output, outputSize, input, cSize);
+ FUZZ_ZASSERT(dSize);
+ FUZZ_ASSERT_MSG(dSize == srcSize, "Incorrect regenerated size");
+ FUZZ_ASSERT_MSG(!FUZZ_memcmp(src, output, srcSize), "Corruption!");
+
+ free(output);
+ }
+
+ /* When superblock is enabled make sure we don't expand the block more than expected.
+ * NOTE: This test is currently disabled because superblock mode can arbitrarily
+ * expand the block in the worst case. Once superblock mode has been improved we can
+ * re-enable this test.
+ */
+ if (0 && targetCBlockSize != 0) {
+ size_t normalCSize;
+ FUZZ_ZASSERT(ZSTD_CCtx_setParameter(cctx, ZSTD_c_targetCBlockSize, 0));
+ normalCSize = ZSTD_compress2(cctx, compressed, compressedCapacity, src, srcSize);
+ FUZZ_ZASSERT(normalCSize);
+ {
+ size_t const bytesPerBlock = 3 /* block header */
+ + 5 /* Literal header */
+ + 6 /* Huffman jump table */
+ + 3 /* number of sequences */
+ + 1 /* symbol compression modes */;
+ size_t const expectedExpansion = bytesPerBlock * (1 + (normalCSize / MAX(1, targetCBlockSize)));
+ size_t const allowedExpansion = (srcSize >> 3) + 5 * expectedExpansion + 10;
+ FUZZ_ASSERT(cSize <= normalCSize + allowedExpansion);
+ }
+ }
+ return dSize;
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
+{
+ FUZZ_SEQ_PROD_SETUP();
+
+ size_t const rBufSize = size;
+ void* rBuf = FUZZ_malloc(rBufSize);
+ size_t cBufSize = ZSTD_compressBound(size);
+ void* cBuf;
+
+ /* Give a random portion of src data to the producer, to use for
+ parameter generation. The rest will be used for (de)compression */
+ FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(src, size);
+ size = FUZZ_dataProducer_reserveDataPrefix(producer);
+
+ /* Half of the time fuzz with a 1 byte smaller output size.
+ * This will still succeed because we don't use a dictionary, so the dictID
+ * field is empty, giving us 4 bytes of overhead.
+ */
+ cBufSize -= FUZZ_dataProducer_uint32Range(producer, 0, 1);
+
+ cBuf = FUZZ_malloc(cBufSize);
+
+ if (!cctx) {
+ cctx = ZSTD_createCCtx();
+ FUZZ_ASSERT(cctx);
+ }
+ if (!dctx) {
+ dctx = ZSTD_createDCtx();
+ FUZZ_ASSERT(dctx);
+ }
+
+ roundTripTest(rBuf, rBufSize, cBuf, cBufSize, src, size, producer);
+ free(rBuf);
+ free(cBuf);
+ FUZZ_dataProducer_free(producer);
+#ifndef STATEFUL_FUZZING
+ ZSTD_freeCCtx(cctx); cctx = NULL;
+ ZSTD_freeDCtx(dctx); dctx = NULL;
+#endif
+ FUZZ_SEQ_PROD_TEARDOWN();
+ return 0;
+}
notaz.gp2x.de / pcsx_rearmed.git / blobdiff