brotli/c/fuzz/decode_fuzzer.c
Evgenii Kliuchnikov 6ee96e291d Internal changes
PiperOrigin-RevId: 545262005
2023-07-04 07:55:25 +00:00

64 lines
1.8 KiB
C

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <brotli/decode.h>
// Entry point for LibFuzzer.
int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
size_t addend = 0;
if (size > 0)
addend = data[size - 1] & 7;
const uint8_t* next_in = data;
const int kBufferSize = 1024;
uint8_t* buffer = (uint8_t*) malloc(kBufferSize);
if (!buffer) {
// OOM is out-of-scope here.
return 0;
}
/* The biggest "magic number" in brotli is 16MiB - 16, so no need to check
the cases with much longer output. */
const size_t total_out_limit = (addend == 0) ? (1 << 26) : (1 << 24);
size_t total_out = 0;
BrotliDecoderState* state = BrotliDecoderCreateInstance(0, 0, 0);
if (!state) {
// OOM is out-of-scope here.
free(buffer);
return 0;
}
if (addend == 0)
addend = size;
/* Test both fast (addend == size) and slow (addend <= 7) decoding paths. */
for (size_t i = 0; i < size;) {
size_t next_i = i + addend;
if (next_i > size)
next_i = size;
size_t avail_in = next_i - i;
i = next_i;
BrotliDecoderResult result = BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT;
while (result == BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT) {
size_t avail_out = kBufferSize;
uint8_t* next_out = buffer;
result = BrotliDecoderDecompressStream(
state, &avail_in, &next_in, &avail_out, &next_out, &total_out);
if (total_out > total_out_limit)
break;
}
if (total_out > total_out_limit)
break;
if (result != BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT)
break;
}
BrotliDecoderDestroyInstance(state);
free(buffer);
return 0;
}