ceph/src/zstd/tests/fuzz/stream_decompress.c

   1 /*
   2  * Copyright (c) 2016-present, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under both the BSD-style license (found in the
   6  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
   7  * in the COPYING file in the root directory of this source tree).
   8  */
   9
  10 /**
  11  * This fuzz target attempts to decompress the fuzzed data with the simple
  12  * decompression function to ensure the decompressor never crashes.
  13  */
  14
  15 #define ZSTD_STATIC_LINKING_ONLY
  16
  17 #include <stddef.h>
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include "fuzz_helpers.h"
  21 #include "zstd.h"
  22
  23 static size_t const kBufSize = ZSTD_BLOCKSIZE_MAX;
  24
  25 static ZSTD_DStream *dstream = NULL;
  26 static void* buf = NULL;
  27 uint32_t seed;
  28
  29 static ZSTD_outBuffer makeOutBuffer(void)
  30 {
  31   ZSTD_outBuffer buffer = { buf, 0, 0 };
  32
  33   buffer.size = (FUZZ_rand(&seed) % kBufSize) + 1;
  34   FUZZ_ASSERT(buffer.size <= kBufSize);
  35
  36   return buffer;
  37 }
  38
  39 static ZSTD_inBuffer makeInBuffer(const uint8_t **src, size_t *size)
  40 {
  41   ZSTD_inBuffer buffer = { *src, 0, 0 };
  42
  43   FUZZ_ASSERT(*size > 0);
  44   buffer.size = (FUZZ_rand(&seed) % *size) + 1;
  45   FUZZ_ASSERT(buffer.size <= *size);
  46   *src += buffer.size;
  47   *size -= buffer.size;
  48
  49   return buffer;
  50 }
  51
  52 int LLVMFuzzerTestOneInput(const uint8_t *src, size_t size)
  53 {
  54     seed = FUZZ_seed(&src, &size);
  55
  56     /* Allocate all buffers and contexts if not already allocated */
  57     if (!buf) {
  58       buf = malloc(kBufSize);
  59       FUZZ_ASSERT(buf);
  60     }
  61
  62     if (!dstream) {
  63         dstream = ZSTD_createDStream();
  64         FUZZ_ASSERT(dstream);
  65         FUZZ_ASSERT(!ZSTD_isError(ZSTD_initDStream(dstream)));
  66     } else {
  67         FUZZ_ASSERT(!ZSTD_isError(ZSTD_resetDStream(dstream)));
  68     }
  69
  70     while (size > 0) {
  71         ZSTD_inBuffer in = makeInBuffer(&src, &size);
  72         while (in.pos != in.size) {
  73             ZSTD_outBuffer out = makeOutBuffer();
  74             size_t const rc = ZSTD_decompressStream(dstream, &out, &in);
  75             if (ZSTD_isError(rc)) goto error;
  76             if (rc == 0) FUZZ_ASSERT(!ZSTD_isError(ZSTD_resetDStream(dstream)));
  77         }
  78     }
  79
  80 error:
  81 #ifndef STATEFUL_FUZZING
  82     ZSTD_freeDStream(dstream); dstream = NULL;
  83 #endif
  84     return 0;
  85 }