xz/tests/ossfuzz/fuzz_decode_stream.c

// SPDX-License-Identifier: 0BSD

///////////////////////////////////////////////////////////////////////////////
//
/// \file       fuzz_decode_stream.c
/// \brief      Fuzz test program for single threaded .xz decoding
//
//  Authors:    Lasse Collin
//              Maksym Vatsyk
//
///////////////////////////////////////////////////////////////////////////////

#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include "lzma.h"
#include "fuzz_common.h"


extern int
LLVMFuzzerTestOneInput(const uint8_t *inbuf, size_t inbuf_size)
{
	lzma_stream strm = LZMA_STREAM_INIT;
	// Initialize a .xz decoder using the memory usage limit
	// defined in fuzz_common.h
	//
	// Enable support for concatenated .xz files which is used when
	// decompressing regular .xz files (instead of data embedded inside
	// some other file format). Integrity checks on the uncompressed
	// data are ignored to make fuzzing more effective (incorrect check
	// values won't prevent the decoder from processing more input).
	//
	// The flag LZMA_IGNORE_CHECK doesn't disable verification of
	// header CRC32 values. Those checks are disabled when liblzma is
	// built with the #define FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION.
	lzma_ret ret = lzma_stream_decoder(&strm, MEM_LIMIT,
			LZMA_CONCATENATED | LZMA_IGNORE_CHECK);

	if (ret != LZMA_OK) {
		// This should never happen unless the system has
		// no free memory or address space to allow the small
		// allocations that the initialization requires.
		fprintf(stderr, "lzma_stream_decoder() failed (%d)\n", ret);
		abort();
	}

	fuzz_code(&strm, inbuf, inbuf_size);

	// Free the allocated memory.
	lzma_end(&strm);

	return 0;
}