1 files changed, 114 insertions, 0 deletions
diff --git a/src/zstd/tests/fuzz/simple_round_trip.c b/src/zstd/tests/fuzz/simple_round_trip.c
new file mode 100644
index 000000000..2f008d06a
--- /dev/null
+++ b/src/zstd/tests/fuzz/simple_round_trip.c
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2016-2020, Facebook, Inc.
+ * 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"
+
+static ZSTD_CCtx *cctx = NULL;
+static ZSTD_DCtx *dctx = NULL;
+
+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)) {
+        FUZZ_setRandomParameters(cctx, srcSize, producer);
+        cSize = ZSTD_compress2(cctx, compressed, compressedCapacity, src, srcSize);
+        FUZZ_ZASSERT(ZSTD_CCtx_getParameter(cctx, ZSTD_c_targetCBlockSize, &targetCBlockSize));
+    } else {
+      int const cLevel = FUZZ_dataProducer_int32Range(producer, kMinClevel, kMaxClevel);
+
+        cSize = ZSTD_compressCCtx(
+            cctx, compressed, compressedCapacity, src, srcSize, cLevel);
+    }
+    FUZZ_ZASSERT(cSize);
+    dSize = ZSTD_decompressDCtx(dctx, result, resultCapacity, compressed, cSize);
+    FUZZ_ZASSERT(dSize);
+    /* When superblock is enabled make sure we don't expand the block more than expected. */
+    if (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)
+{
+    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);
+    }
+
+    {
+        size_t const result =
+            roundTripTest(rBuf, rBufSize, cBuf, cBufSize, src, size, producer);
+        FUZZ_ZASSERT(result);
+        FUZZ_ASSERT_MSG(result == size, "Incorrect regenerated size");
+        FUZZ_ASSERT_MSG(!FUZZ_memcmp(src, rBuf, size), "Corruption!");
+    }
+    free(rBuf);
+    free(cBuf);
+    FUZZ_dataProducer_free(producer);
+#ifndef STATEFUL_FUZZING
+    ZSTD_freeCCtx(cctx); cctx = NULL;
+    ZSTD_freeDCtx(dctx); dctx = NULL;
+#endif
+    return 0;
+}