How to use randBufLen method of prog Package

Best Syzkaller code snippet using prog.randBufLen

rand.go

Source:rand.go

...95	// biasedRand produces: 10, 9, ..., 1, 0,96	// we want: 1, 2, ..., 9, 10, 097	return uint64(maxLen-r.biasedRand(maxLen+1, 10)+1) % (maxLen + 1)98}99func (r *randGen) randBufLen() (n uint64) {100	switch {101	case r.nOutOf(50, 56):102		n = r.rand(256)103	case r.nOutOf(5, 6):104		n = 4 << 10105	}106	return107}108func (r *randGen) randPageCount() (n uint64) {109	switch {110	case r.nOutOf(100, 106):111		n = r.rand(4) + 1112	case r.nOutOf(5, 6):113		n = r.rand(20) + 1114	default:115		n = (r.rand(3) + 1) * 512116	}117	return118}119func (r *randGen) flags(vv []uint64) (v uint64) {120	switch {121	case r.nOutOf(90, 111):122		for stop := false; !stop; stop = r.bin() {123			v |= vv[r.rand(len(vv))]124		}125	case r.nOutOf(10, 21):126		v = vv[r.rand(len(vv))]127	case r.nOutOf(10, 11):128		v = 0129	default:130		v = r.rand64()131	}132	return133}134func (r *randGen) filename(s *state, typ *BufferType) string {135	fn := r.filenameImpl(s)136	if len(fn) != 0 && fn[len(fn)-1] == 0 {137		panic(fmt.Sprintf("zero-terminated filename: %q", fn))138	}139	if !typ.Varlen() {140		size := typ.Size()141		if uint64(len(fn)) < size {142			fn += string(make([]byte, size-uint64(len(fn))))143		}144		fn = fn[:size]145	} else if !typ.NoZ {146		fn += "\x00"147	}148	return fn149}150var specialFiles = []string{"", "/", "."}151func (r *randGen) filenameImpl(s *state) string {152	if r.oneOf(100) {153		return specialFiles[r.Intn(len(specialFiles))]154	}155	if len(s.files) == 0 || r.oneOf(10) {156		// Generate a new name.157		dir := "."158		if r.oneOf(2) && len(s.files) != 0 {159			files := make([]string, 0, len(s.files))160			for f := range s.files {161				files = append(files, f)162			}163			dir = files[r.Intn(len(files))]164			if len(dir) > 0 && dir[len(dir)-1] == 0 {165				dir = dir[:len(dir)-1]166			}167		}168		for i := 0; ; i++ {169			f := fmt.Sprintf("%v/file%v", dir, i)170			if !s.files[f] {171				return f172			}173		}174	}175	files := make([]string, 0, len(s.files))176	for f := range s.files {177		files = append(files, f)178	}179	return files[r.Intn(len(files))]180}181func (r *randGen) randString(s *state, t *BufferType) []byte {182	if len(t.Values) != 0 {183		return []byte(t.Values[r.Intn(len(t.Values))])184	}185	if len(s.strings) != 0 && r.bin() {186		// Return an existing string.187		// TODO(dvyukov): make s.strings indexed by string SubKind.188		strings := make([]string, 0, len(s.strings))189		for s := range s.strings {190			strings = append(strings, s)191		}192		return []byte(strings[r.Intn(len(strings))])193	}194	punct := []byte{'!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '-', '+', '\\',195		'/', ':', '.', ',', '-', '\'', '[', ']', '{', '}'}196	buf := new(bytes.Buffer)197	for r.nOutOf(3, 4) {198		switch {199		case r.nOutOf(10, 21):200			dict := r.target.StringDictionary201			if len(dict) != 0 {202				buf.WriteString(dict[r.Intn(len(dict))])203			}204		case r.nOutOf(10, 11):205			buf.Write([]byte{punct[r.Intn(len(punct))]})206		default:207			buf.Write([]byte{byte(r.Intn(256))})208		}209	}210	if r.oneOf(100) == t.NoZ {211		buf.Write([]byte{0})212	}213	return buf.Bytes()214}215func (r *randGen) allocAddr(s *state, typ Type, size uint64, data Arg) *PointerArg {216	return MakePointerArg(typ, s.ma.alloc(r, size), data)217}218func (r *randGen) allocVMA(s *state, typ Type, numPages uint64) *PointerArg {219	page := s.va.alloc(r, numPages)220	return MakeVmaPointerArg(typ, page*r.target.PageSize, numPages*r.target.PageSize)221}222func (r *randGen) createResource(s *state, res *ResourceType) (arg Arg, calls []*Call) {223	if r.inCreateResource {224		special := res.SpecialValues()225		return MakeResultArg(res, nil, special[r.Intn(len(special))]), nil226	}227	r.inCreateResource = true228	defer func() { r.inCreateResource = false }()229	kind := res.Desc.Name230	if r.oneOf(1000) {231		// Spoof resource subkind.232		var all []string233		for kind1 := range r.target.resourceMap {234			if r.target.isCompatibleResource(res.Desc.Kind[0], kind1) {235				all = append(all, kind1)236			}237		}238		kind = all[r.Intn(len(all))]239	}240	// Find calls that produce the necessary resources.241	metas0 := r.target.resourceCtors[kind]242	// TODO: reduce priority of less specialized ctors.243	var metas []*Syscall244	for _, meta := range metas0 {245		if s.ct == nil || s.ct.run[meta.ID] == nil {246			continue247		}248		metas = append(metas, meta)249	}250	if len(metas) == 0 {251		return MakeResultArg(res, nil, res.Default()), nil252	}253	// Now we have a set of candidate calls that can create the necessary resource.254	for i := 0; i < 1e3; i++ {255		// Generate one of them.256		meta := metas[r.Intn(len(metas))]257		calls := r.generateParticularCall(s, meta)258		s1 := newState(r.target, s.ct)259		s1.analyze(calls[len(calls)-1])260		// Now see if we have what we want.261		var allres []Arg262		for kind1, res1 := range s1.resources {263			if r.target.isCompatibleResource(kind, kind1) {264				allres = append(allres, res1...)265			}266		}267		if len(allres) != 0 {268			// Bingo!269			arg := MakeResultArg(res, allres[r.Intn(len(allres))], 0)270			return arg, calls271		}272		// Discard unsuccessful calls.273		// Note: s.ma/va have already noted allocations of the new objects274		// in discarded syscalls, ideally we should recreate state275		// by analyzing the program again.276		for _, c := range calls {277			ForeachArg(c, func(arg Arg, _ *ArgCtx) {278				if a, ok := arg.(*ResultArg); ok && a.Res != nil {279					delete(*a.Res.(ArgUsed).Used(), arg)280				}281			})282		}283	}284	// Generally we can loop several times, e.g. when we choose a call that returns285	// the resource in an array, but then generateArg generated that array of zero length.286	// But we must succeed eventually.287	var ctors []string288	for _, meta := range metas {289		ctors = append(ctors, meta.Name)290	}291	panic(fmt.Sprintf("failed to create a resource %v with %v",292		res.Desc.Kind[0], strings.Join(ctors, ", ")))293}294func (r *randGen) generateText(kind TextKind) []byte {295	switch kind {296	case Text_arm64:297		// Just a stub, need something better.298		text := make([]byte, 50)299		for i := range text {300			text[i] = byte(r.Intn(256))301		}302		return text303	default:304		cfg := createIfuzzConfig(kind)305		return ifuzz.Generate(cfg, r.Rand)306	}307}308func (r *randGen) mutateText(kind TextKind, text []byte) []byte {309	switch kind {310	case Text_arm64:311		return mutateData(r, text, 40, 60)312	default:313		cfg := createIfuzzConfig(kind)314		return ifuzz.Mutate(cfg, r.Rand, text)315	}316}317func createIfuzzConfig(kind TextKind) *ifuzz.Config {318	cfg := &ifuzz.Config{319		Len:  10,320		Priv: true,321		Exec: true,322		MemRegions: []ifuzz.MemRegion{323			{0 << 12, 1 << 12},324			{1 << 12, 1 << 12},325			{2 << 12, 1 << 12},326			{3 << 12, 1 << 12},327			{4 << 12, 1 << 12},328			{5 << 12, 1 << 12},329			{6 << 12, 1 << 12},330			{7 << 12, 1 << 12},331			{8 << 12, 1 << 12},332			{9 << 12, 1 << 12},333			{0xfec00000, 0x100}, // ioapic334		},335	}336	switch kind {337	case Text_x86_real:338		cfg.Mode = ifuzz.ModeReal16339	case Text_x86_16:340		cfg.Mode = ifuzz.ModeProt16341	case Text_x86_32:342		cfg.Mode = ifuzz.ModeProt32343	case Text_x86_64:344		cfg.Mode = ifuzz.ModeLong64345	}346	return cfg347}348// nOutOf returns true n out of outOf times.349func (r *randGen) nOutOf(n, outOf int) bool {350	if n <= 0 || n >= outOf {351		panic("bad probability")352	}353	v := r.Intn(outOf)354	return v < n355}356func (r *randGen) generateCall(s *state, p *Prog) []*Call {357	idx := 0358	if s.ct == nil {359		idx = r.Intn(len(r.target.Syscalls))360	} else {361		call := -1362		if len(p.Calls) != 0 {363			call = p.Calls[r.Intn(len(p.Calls))].Meta.ID364		}365		idx = s.ct.Choose(r.Rand, call)366	}367	meta := r.target.Syscalls[idx]368	return r.generateParticularCall(s, meta)369}370func (r *randGen) generateParticularCall(s *state, meta *Syscall) (calls []*Call) {371	c := &Call{372		Meta: meta,373		Ret:  MakeReturnArg(meta.Ret),374	}375	c.Args, calls = r.generateArgs(s, meta.Args)376	r.target.assignSizesCall(c)377	calls = append(calls, c)378	for _, c1 := range calls {379		r.target.SanitizeCall(c1)380	}381	return calls382}383// GenerateAllSyzProg generates a program that contains all pseudo syz_ calls for testing.384func (target *Target) GenerateAllSyzProg(rs rand.Source) *Prog {385	p := &Prog{386		Target: target,387	}388	r := newRand(target, rs)389	s := newState(target, nil)390	handled := make(map[string]bool)391	for _, meta := range target.Syscalls {392		if !strings.HasPrefix(meta.CallName, "syz_") || handled[meta.CallName] {393			continue394		}395		handled[meta.CallName] = true396		calls := r.generateParticularCall(s, meta)397		for _, c := range calls {398			s.analyze(c)399			p.Calls = append(p.Calls, c)400		}401	}402	if err := p.validate(); err != nil {403		panic(err)404	}405	return p406}407// GenerateSimpleProg generates the simplest non-empty program for testing408// (e.g. containing a single mmap).409func (target *Target) GenerateSimpleProg() *Prog {410	return &Prog{411		Target: target,412		Calls:  []*Call{target.MakeMmap(0, target.PageSize)},413	}414}415func (target *Target) GenerateUberMmapProg() *Prog {416	return &Prog{417		Target: target,418		Calls:  []*Call{target.MakeMmap(0, target.NumPages*target.PageSize)},419	}420}421func (r *randGen) generateArgs(s *state, types []Type) ([]Arg, []*Call) {422	var calls []*Call423	args := make([]Arg, len(types))424	// Generate all args. Size args have the default value 0 for now.425	for i, typ := range types {426		arg, calls1 := r.generateArg(s, typ)427		if arg == nil {428			panic(fmt.Sprintf("generated arg is nil for type '%v', types: %+v", typ.Name(), types))429		}430		args[i] = arg431		calls = append(calls, calls1...)432	}433	return args, calls434}435func (r *randGen) generateArg(s *state, typ Type) (arg Arg, calls []*Call) {436	return r.generateArgImpl(s, typ, false)437}438func (r *randGen) generateArgImpl(s *state, typ Type, ignoreSpecial bool) (arg Arg, calls []*Call) {439	if typ.Dir() == DirOut {440		// No need to generate something interesting for output scalar arguments.441		// But we still need to generate the argument itself so that it can be referenced442		// in subsequent calls. For the same reason we do generate pointer/array/struct443		// output arguments (their elements can be referenced in subsequent calls).444		switch typ.(type) {445		case *IntType, *FlagsType, *ConstType, *ProcType,446			*VmaType, *ResourceType:447			return r.target.defaultArg(typ), nil448		}449	}450	if typ.Optional() && r.oneOf(5) {451		return r.target.defaultArg(typ), nil452	}453	// Allow infinite recursion for optional pointers.454	if pt, ok := typ.(*PtrType); ok && typ.Optional() {455		switch pt.Type.(type) {456		case *StructType, *ArrayType, *UnionType:457			name := pt.Type.Name()458			r.recDepth[name]++459			defer func() {460				r.recDepth[name]--461				if r.recDepth[name] == 0 {462					delete(r.recDepth, name)463				}464			}()465			if r.recDepth[name] >= 3 {466				return MakeNullPointerArg(typ), nil467			}468		}469	}470	switch a := typ.(type) {471	case *ResourceType:472		switch {473		case r.nOutOf(1000, 1011):474			// Get an existing resource.475			var allres []Arg476			for name1, res1 := range s.resources {477				if name1 == "iocbptr" {478					continue479				}480				if r.target.isCompatibleResource(a.Desc.Name, name1) ||481					r.oneOf(20) && r.target.isCompatibleResource(a.Desc.Kind[0], name1) {482					allres = append(allres, res1...)483				}484			}485			if len(allres) != 0 {486				arg = MakeResultArg(a, allres[r.Intn(len(allres))], 0)487			} else {488				arg, calls = r.createResource(s, a)489			}490		case r.nOutOf(10, 11):491			// Create a new resource.492			arg, calls = r.createResource(s, a)493		default:494			special := a.SpecialValues()495			arg = MakeResultArg(a, nil, special[r.Intn(len(special))])496		}497		return arg, calls498	case *BufferType:499		switch a.Kind {500		case BufferBlobRand, BufferBlobRange:501			sz := r.randBufLen()502			if a.Kind == BufferBlobRange {503				sz = r.randRange(a.RangeBegin, a.RangeEnd)504			}505			if a.Dir() == DirOut {506				return MakeOutDataArg(a, sz), nil507			}508			data := make([]byte, sz)509			for i := range data {510				data[i] = byte(r.Intn(256))511			}512			return MakeDataArg(a, data), nil513		case BufferString:514			data := r.randString(s, a)515			if a.Dir() == DirOut {...

randBufLen

Using AI Code Generation

1import (2func main() {3    rand.Seed(time.Now().UnixNano())4    for i := 0; i < 10; i++ {5        fmt.Println(randBufLen())6    }7}8import (9func main() {10    rand.Seed(time.Now().UnixNano())11    for i := 0; i < 10; i++ {12        fmt.Println(randBufLen())13    }14}15import (16func randBufLen() int {17    rand.Seed(time.Now().UnixNano())18    return rand.Intn(100)19}

randBufLen

Using AI Code Generation

1import (2func main() {3    rand.Seed(time.Now().UnixNano())4    fmt.Println(randBufLen())5}6import (7func main() {8    rand.Seed(time.Now().UnixNano())9    fmt.Println(randBufLen())10}11import (12func main() {13    rand.Seed(time.Now().UnixNano())14    fmt.Println(randBufLen())15}16import (17func main() {18    rand.Seed(time.Now().UnixNano())19    fmt.Println(randBufLen())20}21import (22func main() {23    rand.Seed(time.Now().UnixNano())24    fmt.Println(randBufLen())25}26import (27func main() {28    rand.Seed(time.Now().UnixNano())29    fmt.Println(randBufLen())30}31import (32func main() {33    rand.Seed(time.Now().UnixNano())34    fmt.Println(randBufLen())35}36import (37func main() {38    rand.Seed(time.Now().UnixNano())39    fmt.Println(randBufLen())40}41import (

randBufLen

Using AI Code Generation

1import "fmt"2func main() {3    fmt.Println(prog.randBufLen())4}5import "fmt"6func main() {7    fmt.Println(prog.randBufLen())8}9import "fmt"10func main() {11    fmt.Println(prog.randBufLen())12}13import "fmt"14func main() {15    fmt.Println(prog.randBufLen())16}17import "fmt"18func main() {19    fmt.Println(prog.randBufLen())20}21import "fmt"22func main() {23    fmt.Println(prog.randBufLen())24}25import "fmt"26func main() {27    fmt.Println(prog.randBufLen())28}29import "fmt"30func main() {31    fmt.Println(prog.randBufLen())32}33import "fmt"34func main() {35    fmt.Println(prog.randBufLen())36}37import "fmt"38func main() {39    fmt.Println(prog.randBufLen())40}41import "fmt"42func main() {43    fmt.Println(prog.randBufLen())44}45import "fmt"46func main() {47    fmt.Println(prog.randBufLen())48}49import "fmt"50func main() {51    fmt.Println(prog.randBufLen())52}

randBufLen

Using AI Code Generation

1import "fmt"2func main() {3  fmt.Println(prog.randBufLen())4}5import "fmt"6func main() {7  fmt.Println(prog.randBuf())8}

randBufLen

Using AI Code Generation

1import (2type prog struct {3}4func (p prog) randBufLen() int {5    rand.Seed(time.Now().UnixNano())6    return rand.Intn(100)7}8func main() {9    p := prog{1, "test"}10    fmt.Println(p.randBufLen())11    fmt.Println(p.randBufLen())12    fmt.Println(p.randBufLen())13}14import "fmt"15func (i *int) inc() {16}17func main() {18    i.inc()19    fmt.Println(i)20}21import "fmt"22func (i int) inc() {23}24func main() {25    i.inc()26    fmt.Println(i)

randBufLen

Using AI Code Generation

1import "fmt"2func main() {3    p.randBufLen()4    fmt.Println(p.bufLen)5}6import "fmt"7func main() {8    p.randBufLen()9    fmt.Println(p.bufLen)10}11import "fmt"12func main() {13    p.randBufLen()14    fmt.Println(p.bufLen)15}16import "fmt"17func main() {18    p.randBufLen()19    fmt.Println(p.bufLen)20}21import "fmt"22func main() {23    p.randBufLen()24    fmt.Println(p.bufLen)25}26import "fmt"27func main() {28    p.randBufLen()29    fmt.Println(p.bufLen)30}31import "fmt"32func main() {33    p.randBufLen()34    fmt.Println(p.bufLen)35}36import "fmt"37func main() {38    p.randBufLen()39    fmt.Println(p.bufLen)40}41import "fmt"42func main() {43    p.randBufLen()44    fmt.Println(p.bufLen)45}46import "fmt"47func main() {48    p.randBufLen()49    fmt.Println(p.bufLen)50}51import "fmt"

randBufLen

Using AI Code Generation

1import "fmt"2func main() {3    fmt.Println("Hello, World!")4    p.randBufLen()5}6import "fmt"7type prog struct {8}9func (p *prog) randBufLen() {10    fmt.Println("Hello, World!")11}12import "fmt"13type prog struct {14}15func (p *prog) RandBufLen() {16    fmt.Println("Hello, World!")17}18func main() {19    fmt.Println("Hello, World!")20    p.RandBufLen()21}

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