github.com/google/syzkaller@v0.0.0-20240517125934-c0f1611a36d6/tools/syz-repro/repro.go (about)

     1  // Copyright 2015 syzkaller project authors. All rights reserved.
     2  // Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
     3  
     4  package main
     5  
     6  import (
     7  	"flag"
     8  	"fmt"
     9  	"os"
    10  	"path/filepath"
    11  
    12  	"github.com/google/syzkaller/pkg/csource"
    13  	"github.com/google/syzkaller/pkg/flatrpc"
    14  	"github.com/google/syzkaller/pkg/log"
    15  	"github.com/google/syzkaller/pkg/mgrconfig"
    16  	"github.com/google/syzkaller/pkg/osutil"
    17  	"github.com/google/syzkaller/pkg/report"
    18  	"github.com/google/syzkaller/pkg/repro"
    19  	"github.com/google/syzkaller/vm"
    20  )
    21  
    22  var (
    23  	flagConfig = flag.String("config", "", "manager configuration file (manager.cfg)")
    24  	flagCount  = flag.Int("count", 0, "number of VMs to use (overrides config count param)")
    25  	flagDebug  = flag.Bool("debug", false, "print debug output")
    26  	flagOutput = flag.String("output", filepath.Join(".", "repro.txt"), "output syz repro file (repro.txt)")
    27  	flagCRepro = flag.String("crepro", filepath.Join(".", "repro.c"), "output c file (repro.c)")
    28  	flagTitle  = flag.String("title", "", "where to save the title of the reproduced bug")
    29  	flagStrace = flag.String("strace", "", "output strace log (strace_bin must be set)")
    30  )
    31  
    32  func main() {
    33  	os.Args = append(append([]string{}, os.Args[0], "-vv=10"), os.Args[1:]...)
    34  	flag.Parse()
    35  	if len(flag.Args()) != 1 || *flagConfig == "" {
    36  		log.Fatalf("usage: syz-repro -config=manager.cfg execution.log")
    37  	}
    38  	cfg, err := mgrconfig.LoadFile(*flagConfig)
    39  	if err != nil {
    40  		log.Fatalf("%v: %v", *flagConfig, err)
    41  	}
    42  	logFile := flag.Args()[0]
    43  	data, err := os.ReadFile(logFile)
    44  	if err != nil {
    45  		log.Fatalf("failed to open log file %v: %v", logFile, err)
    46  	}
    47  	vmPool, err := vm.Create(cfg, *flagDebug)
    48  	if err != nil {
    49  		log.Fatalf("%v", err)
    50  	}
    51  	vmCount := vmPool.Count()
    52  	if *flagCount > 0 && *flagCount < vmCount {
    53  		vmCount = *flagCount
    54  	}
    55  	if vmCount > 4 {
    56  		vmCount = 4
    57  	}
    58  	vmIndexes := make([]int, vmCount)
    59  	for i := range vmIndexes {
    60  		vmIndexes[i] = i
    61  	}
    62  	reporter, err := report.NewReporter(cfg)
    63  	if err != nil {
    64  		log.Fatalf("%v", err)
    65  	}
    66  	osutil.HandleInterrupts(vm.Shutdown)
    67  
    68  	res, stats, err := repro.Run(data, cfg, flatrpc.AllFeatures, reporter, vmPool, vmIndexes)
    69  	if err != nil {
    70  		log.Logf(0, "reproduction failed: %v", err)
    71  	}
    72  	if stats != nil {
    73  		fmt.Printf("extracting prog: %v\n", stats.ExtractProgTime)
    74  		fmt.Printf("minimizing prog: %v\n", stats.MinimizeProgTime)
    75  		fmt.Printf("simplifying prog options: %v\n", stats.SimplifyProgTime)
    76  		fmt.Printf("extracting C: %v\n", stats.ExtractCTime)
    77  		fmt.Printf("simplifying C: %v\n", stats.SimplifyCTime)
    78  	}
    79  	if res == nil {
    80  		return
    81  	}
    82  
    83  	fmt.Printf("opts: %+v crepro: %v\n\n", res.Opts, res.CRepro)
    84  
    85  	progSerialized := res.Prog.Serialize()
    86  	fmt.Printf("%s\n", progSerialized)
    87  	if err = osutil.WriteFile(*flagOutput, progSerialized); err == nil {
    88  		fmt.Printf("program saved to %s\n", *flagOutput)
    89  	} else {
    90  		log.Logf(0, "failed to write prog to file: %v", err)
    91  	}
    92  
    93  	if res.Report != nil && *flagTitle != "" {
    94  		recordTitle(res, *flagTitle)
    95  	}
    96  	if res.CRepro {
    97  		recordCRepro(res, *flagCRepro)
    98  	}
    99  	if *flagStrace != "" {
   100  		result := repro.RunStrace(res, cfg, reporter, vmPool, vmIndexes[0])
   101  		recordStraceResult(result, *flagStrace)
   102  	}
   103  }
   104  
   105  func recordTitle(res *repro.Result, fileName string) {
   106  	if err := osutil.WriteFile(fileName, []byte(res.Report.Title)); err == nil {
   107  		fmt.Printf("bug title saved to %s\n", *flagTitle)
   108  	} else {
   109  		log.Logf(0, "failed to write bug title to file: %v", err)
   110  	}
   111  }
   112  
   113  func recordCRepro(res *repro.Result, fileName string) {
   114  	src, err := csource.Write(res.Prog, res.Opts)
   115  	if err != nil {
   116  		log.Fatalf("failed to generate C repro: %v", err)
   117  	}
   118  	if formatted, err := csource.Format(src); err == nil {
   119  		src = formatted
   120  	}
   121  	fmt.Printf("%s\n", src)
   122  
   123  	if err := osutil.WriteFile(fileName, src); err == nil {
   124  		fmt.Printf("C file saved to %s\n", *flagCRepro)
   125  	} else {
   126  		log.Logf(0, "failed to write C repro to file: %v", err)
   127  	}
   128  }
   129  
   130  func recordStraceResult(result *repro.StraceResult, fileName string) {
   131  	if result.Error != nil {
   132  		log.Logf(0, "failed to run strace: %v", result.Error)
   133  		return
   134  	}
   135  	if result.Report != nil {
   136  		log.Logf(0, "under strace repro crashed with title: %s", result.Report.Title)
   137  	} else {
   138  		log.Logf(0, "repro didn't crash under strace")
   139  	}
   140  	if err := osutil.WriteFile(fileName, result.Output); err == nil {
   141  		fmt.Printf("C file saved to %s\n", *flagStrace)
   142  	} else {
   143  		log.Logf(0, "failed to write strace output to file: %v", err)
   144  	}
   145  }