xz/tests/ossfuzz/fuzz_common.h

54 lines
1.7 KiB
C

///////////////////////////////////////////////////////////////////////////////
//
/// \file fuzz_common.h
/// \brief Common macros and functions needed by the fuzz targets
//
// Authors: Maksym Vatsyk
// Lasse Collin
//
///////////////////////////////////////////////////////////////////////////////
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include "lzma.h"
// Some header values can make liblzma allocate a lot of RAM
// (up to about 4 GiB with liblzma 5.2.x). We set a limit here to
// prevent extreme allocations when fuzzing.
#define MEM_LIMIT (300 << 20) // 300 MiB
static void
fuzz_code(lzma_stream *stream, const uint8_t *inbuf, size_t inbuf_size) {
// Output buffer for decompressed data. This is write only; nothing
// cares about the actual data written here.
uint8_t outbuf[4096];
// Give the whole input buffer at once to liblzma.
// Output buffer isn't initialized as liblzma only writes to it.
stream->next_in = inbuf;
stream->avail_in = inbuf_size;
stream->next_out = outbuf;
stream->avail_out = sizeof(outbuf);
lzma_ret ret;
while ((ret = lzma_code(stream, LZMA_FINISH)) == LZMA_OK) {
if (stream->avail_out == 0) {
// outbuf became full. We don't care about the
// uncompressed data there, so we simply reuse
// the outbuf and overwrite the old data.
stream->next_out = outbuf;
stream->avail_out = sizeof(outbuf);
}
}
// LZMA_PROG_ERROR should never happen as long as the code calling
// the liblzma functions is correct. Thus LZMA_PROG_ERROR is a sign
// of a bug in either this function or in liblzma.
if (ret == LZMA_PROG_ERROR) {
fprintf(stderr, "lzma_code() returned LZMA_PROG_ERROR\n");
abort();
}
}