[fuzz] Move from fuzz/ to tests/fuzz/

tests/fuzz/stream_decompress.c

@@ -0,0 +1,85 @@
+/**
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+/**
+ * This fuzz target attempts to decompress the fuzzed data with the simple
+ * decompression function to ensure the decompressor never crashes.
+ */
+
+#define ZSTD_STATIC_LINKING_ONLY
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include "fuzz_helpers.h"
+#include "zstd.h"
+
+static size_t const kBufSize = ZSTD_BLOCKSIZE_ABSOLUTEMAX;
+
+static ZSTD_DStream *dstream = NULL;
+static void* buf = NULL;
+uint32_t seed;
+
+static ZSTD_outBuffer makeOutBuffer(void)
+{
+  ZSTD_outBuffer buffer = { buf, 0, 0 };
+
+  buffer.size = (FUZZ_rand(&seed) % kBufSize) + 1;
+  FUZZ_ASSERT(buffer.size <= kBufSize);
+
+  return buffer;
+}
+
+static ZSTD_inBuffer makeInBuffer(const uint8_t **src, size_t *size)
+{
+  ZSTD_inBuffer buffer = { *src, 0, 0 };
+
+  FUZZ_ASSERT(*size > 0);
+  buffer.size = (FUZZ_rand(&seed) % *size) + 1;
+  FUZZ_ASSERT(buffer.size <= *size);
+  *src += buffer.size;
+  *size -= buffer.size;
+
+  return buffer;
+}
+
+int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
+{
+    seed = FUZZ_seed(src, size);
+
+    /* Allocate all buffers and contexts if not already allocated */
+    if (!buf) {
+      buf = malloc(kBufSize);
+      FUZZ_ASSERT(buf);
+    }
+
+    if (!dstream) {
+        dstream = ZSTD_createDStream();
+        FUZZ_ASSERT(dstream);
+        FUZZ_ASSERT(!ZSTD_isError(ZSTD_initDStream(dstream)));
+    } else {
+        FUZZ_ASSERT(!ZSTD_isError(ZSTD_resetDStream(dstream)));
+    }
+
+    while (size > 0) {
+        ZSTD_inBuffer in = makeInBuffer(&src, &size);
+        while (in.pos != in.size) {
+            ZSTD_outBuffer out = makeOutBuffer();
+            size_t const rc = ZSTD_decompressStream(dstream, &out, &in);
+            if (ZSTD_isError(rc)) goto error;
+            if (rc == 0) FUZZ_ASSERT(!ZSTD_isError(ZSTD_resetDStream(dstream)));
+        }
+    }
+
+error:
+#ifndef STATEFULL_FUZZING
+    ZSTD_freeDStream(dstream); dstream = NULL;
+#endif
+    return 0;
+}