Coverage Report

Created: 2023-08-28 06:31

/src/fuzz_as.c
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Source (jump to first uncovered line)
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/* Copyright 2021 Google LLC
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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      http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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/*
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 * We convert as.c into a header file to make convenient for fuzzing.
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 * We do this for several of the binutils applications when creating
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 * the binutils fuzzers.
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 */
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#include <fuzz_as.h>
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/* Don't allow cleanups.  libiberty's function of the same name adds
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   cleanups to a list without any means of clearing the list.  The
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   list must be clear at the start if LLVMFuzzerTestOneInput is to run
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   more than once, otherwise we will get multiple copies of the same
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   cleanup on the list which leads to double frees if xexit is called.
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   Also a cleanup from the first run can result in use-after-free
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   errors when as_fatal is hit as in issue 56429.  */
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int
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xatexit (void (*fn) (void) ATTRIBUTE_UNUSED)
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2.30k
{
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  return 0;
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}
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int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
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int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
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  char filename[256];
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  sprintf(filename, "/tmp/libfuzzer-%d.s", getpid());
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  FILE *fp = fopen(filename, "wb");
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  if (!fp) {
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0
    return 0;
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0
  }
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  fwrite(data, size, 1, fp);
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  fclose(fp);
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  reg_section = NULL;
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  char *fakeArgv[3];
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  fakeArgv[0] = "fuzz_as";
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  fakeArgv[1] = filename; // Assemble our fake source file.
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  fakeArgv[2] = NULL;
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  int argc = 2;
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  char **argv = fakeArgv;
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  gas_early_init (&argc, &argv);
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  out_file_name = "/tmp/tmp-out";
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  gas_init ();
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  // Main fuzzer target. Assemble our random data.
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  perform_an_assembly_pass (argc, argv);
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  // Cleanup
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  cond_finish_check (-1);
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  codeview_finish ();
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  dwarf2_finish ();
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  cfi_finish ();
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  input_scrub_end ();
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  keep_it = 0;
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  output_file_close ();
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  free_notes ();
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  unlink(filename);
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  return 0;
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}