1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
|
// Copyright 2017 syzkaller project authors. All rights reserved.
// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
//go:generate bash -c "echo -en '// AUTOGENERATED FILE\n\n' > generated.go"
//go:generate bash -c "echo -en 'package kernel\n\n' >> generated.go"
//go:generate bash -c "echo -en 'const createImageScript = `#!/bin/bash\n' >> generated.go"
//go:generate bash -c "cat ../../tools/create-gce-image.sh | grep -v '#' >> generated.go"
//go:generate bash -c "echo -en '`\n\n' >> generated.go"
// Package kernel contains helper functions for working with Linux kernel
// (building kernel/image).
package kernel
import (
"fmt"
"io/ioutil"
"os"
"path/filepath"
"runtime"
"strconv"
"strings"
"time"
"github.com/google/syzkaller/pkg/osutil"
)
func Build(dir, compiler, config string, fullConfig bool) error {
const timeout = 10 * time.Minute // default timeout for command invocations
if fullConfig {
if err := ioutil.WriteFile(filepath.Join(dir, ".config"), []byte(config), 0600); err != nil {
return fmt.Errorf("failed to write config file: %v", err)
}
} else {
os.Remove(filepath.Join(dir, ".config"))
configFile := filepath.Join(dir, "syz.config")
if err := ioutil.WriteFile(configFile, []byte(config), 0600); err != nil {
return fmt.Errorf("failed to write config file: %v", err)
}
defer os.Remove(configFile)
if _, err := osutil.RunCmd(timeout, dir, "make", "defconfig"); err != nil {
return err
}
if _, err := osutil.RunCmd(timeout, dir, "make", "kvmconfig"); err != nil {
return err
}
if _, err := osutil.RunCmd(timeout, dir, "scripts/kconfig/merge_config.sh", "-n", ".config", configFile); err != nil {
return err
}
}
if _, err := osutil.RunCmd(timeout, dir, "make", "olddefconfig"); err != nil {
return err
}
// We build only bzImage as we currently don't use modules.
// Build of a large kernel can take a while on a 1 CPU VM.
if _, err := osutil.RunCmd(3*time.Hour, dir, "make", "bzImage", "-j", strconv.Itoa(runtime.NumCPU()*2), "CC="+compiler); err != nil {
return err
}
return nil
}
// CreateImage creates a disk image that is suitable for syzkaller.
// Kernel is taken from kernelDir, userspace system is taken from userspaceDir.
// The resulting image is marked with tag and copied to the specified image file.
func CreateImage(kernelDir, userspaceDir, tag, image string) error {
tempDir, err := ioutil.TempDir("", "syz-build")
if err != nil {
return err
}
defer os.RemoveAll(tempDir)
scriptFile := filepath.Join(tempDir, "create.sh")
if err := ioutil.WriteFile(scriptFile, []byte(createImageScript), 0700); err != nil {
return fmt.Errorf("failed to write script file: %v", err)
}
vmlinux := filepath.Join(kernelDir, "vmlinux")
bzImage := filepath.Join(kernelDir, "arch/x86/boot/bzImage")
if _, err := osutil.RunCmd(time.Hour, tempDir, scriptFile, userspaceDir, bzImage, vmlinux, tag); err != nil {
return fmt.Errorf("image build failed: %v", err)
}
if err := os.Rename(filepath.Join(tempDir, "image.tar.gz"), image); err != nil {
return err
}
return nil
}
func CompilerIdentity(compiler string) (string, error) {
output, err := osutil.RunCmd(time.Minute, "", compiler, "--version")
if err != nil {
return "", err
}
if len(output) == 0 {
return "", fmt.Errorf("no output from compiler --version")
}
return strings.Split(string(output), "\n")[0], nil
}
|
