[fuzzer] Add huf_decompress fuzzer

Add a fuzzer for Huffman decompression. Fix several bugs in Huffman decompression, mostly related to `op == NULL` and pointer underflow.
2021-09-17 15:00:49 -07:00
parent 6392c382bf
commit d7542aacd9
4 changed files with 159 additions and 78 deletions
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 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 HUF_STATIC_LINKING_ONLY
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "common/cpu.h"
+#include "common/huf.h"
+#include "fuzz_helpers.h"
+#include "fuzz_data_producer.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
+{
+    FUZZ_dataProducer_t *producer = FUZZ_dataProducer_create(src, size);
+    /* Select random parameters: #streams, X1 or X2 decoding, bmi2 */
+    int const streams = FUZZ_dataProducer_int32Range(producer, 0, 1);
+    int const symbols = FUZZ_dataProducer_int32Range(producer, 0, 1);
+    int const bmi2 = ZSTD_cpuid_bmi2(ZSTD_cpuid()) && FUZZ_dataProducer_int32Range(producer, 0, 1);
+    /* Select a random cBufSize - it may be too small */
+    size_t const dBufSize = FUZZ_dataProducer_uint32Range(producer, 0, 8 * size + 500);
+    size_t const maxTableLog = FUZZ_dataProducer_uint32Range(producer, 1, HUF_TABLELOG_MAX);
+    HUF_DTable* dt = (HUF_DTable*)FUZZ_malloc(HUF_DTABLE_SIZE(maxTableLog) * sizeof(HUF_DTable));
+    size_t const wkspSize = HUF_WORKSPACE_SIZE;
+    void* wksp = FUZZ_malloc(wkspSize);
+    void* dBuf = FUZZ_malloc(dBufSize);
+    dt[0] = maxTableLog * 0x01000001;
+    size = FUZZ_dataProducer_remainingBytes(producer);
+
+    if (symbols == 0) {
+        size_t const err = HUF_readDTableX1_wksp_bmi2(dt, src, size, wksp, wkspSize, bmi2);
+        if (ZSTD_isError(err))
+            goto _out;
+    } else {
+        size_t const err = HUF_readDTableX2_wksp(dt, src, size, wksp, wkspSize);
+        if (ZSTD_isError(err))
+            goto _out;
+    }
+    if (streams == 0)
+        HUF_decompress1X_usingDTable_bmi2(dBuf, dBufSize, src, size, dt, bmi2);
+    else
+        HUF_decompress4X_usingDTable_bmi2(dBuf, dBufSize, src, size, dt, bmi2);
+
+_out:
+    free(dt);
+    free(wksp);
+    free(dBuf);
+    FUZZ_dataProducer_free(producer);
+    return 0;
+}