How to use processOpcodes method of report Package

Best Syzkaller code snippet using report.processOpcodes

linux.go

Source:linux.go

...444	opcodes           []DecompiledOpcode445	trappingOpcodeIdx int446	leftBytesCut      int447}448// processOpcodes converts a string representation of opcodes used by the Linux kernel into449// a sequence of the machine instructions, that surround the one that crashed the kernel.450// If the input does not start on a boundary of an instruction, it is attempted to adjust the451// strting position.452// The method returns an error if it did not manage to correctly decompile the opcodes or453// of the decompiled code is not of interest to the reader (e.g. it is a user-space code).454func (ctx *linux) processOpcodes(codeSlice string) (*decompiledOpcodes, error) {455	parsed, err := ctx.parseOpcodes(codeSlice)456	if err != nil {457		return nil, err458	}459	decompiled, err := ctx.decompileWithOffset(parsed)460	if err != nil {461		return nil, err462	}463	if linuxSkipTrapInstrRe.MatchString(decompiled.opcodes[decompiled.trappingOpcodeIdx].Instruction) {464		// For some reports (like WARNINGs) the trapping instruction is an intentionally465		// invalid instruction. Decompilation of such code only allows to see the466		// mechanism, through which the kernel implements such assertions and does not467		// aid in finding the real issue.468		return nil, fmt.Errorf("these opcodes are not of interest")469	}470	return decompiled, nil471}472func (ctx *linux) decompileWithOffset(parsed parsedOpcodes) (*decompiledOpcodes, error) {473	// It is not guaranteed that the fragment of opcodes starts exactly at the boundary474	// of a machine instruction. In order to simplify debugging process, we are trying475	// to find the right starting position.476	//477	// We iterate over a fixed number of left boundaries. The exact number of iterations478	// should strike a balance between the potential usefulness and the extra time needed479	// to invoke the decompiler.480	const opcodeAdjustmentLimit = 8481	var bestResult *decompiledOpcodes482	for leftCut := 0; leftCut <= parsed.offset && leftCut < opcodeAdjustmentLimit; leftCut++ {483		newBytes := parsed.rawBytes[leftCut:]484		newOffset := parsed.offset - leftCut485		instructions, err := DecompileOpcodes(newBytes, parsed.decompileFlags, ctx.target)486		if err != nil {487			return nil, err488		}489		// We only want to return the response, where there exists a decoded instruction that490		// perfectly aligns with the trapping instruction offset.491		// At the same time, we'll do out best to find a code listing that does not contain492		// unrecognized (bad) instuctions - this serves as an indicator of a valid result.493		hasBad := false494		trappingIdx := -1495		for idx, instruction := range instructions {496			if instruction.Offset == newOffset {497				trappingIdx = idx498			}499			if instruction.Offset >= newOffset {500				// Do not take into account instructions after the target offset. Once501				// decompiler begins to find the right boundary, we cannot improve them.502				break503			}504			hasBad = hasBad || instruction.IsBad505		}506		if trappingIdx < 0 {507			continue508		}509		if !hasBad || bestResult == nil {510			bestResult = &decompiledOpcodes{511				opcodes:           instructions,512				trappingOpcodeIdx: trappingIdx,513				leftBytesCut:      leftCut,514			}515			if !hasBad {516				// The best offset is already found.517				break518			}519		}520	}521	if bestResult == nil {522		return nil, fmt.Errorf("unable to align decompiled code and the trapping instruction offset")523	}524	return bestResult, nil525}526func (ctx *linux) parseOpcodes(codeSlice string) (parsedOpcodes, error) {527	binaryOps := binary.ByteOrder(binary.BigEndian)528	if ctx.target.LittleEndian {529		binaryOps = binary.LittleEndian530	}531	width := 0532	bytes := []byte{}533	trapOffset := -1534	for _, part := range strings.Split(strings.TrimSpace(codeSlice), " ") {535		if part == "" || len(part)%2 != 0 {536			return parsedOpcodes{}, fmt.Errorf("invalid opcodes string %#v", part)537		}538		// Check if this is a marker of a trapping instruction.539		if part[0] == '(' || part[0] == '<' {540			if trapOffset >= 0 {541				return parsedOpcodes{}, fmt.Errorf("invalid opcodes string: multiple trap intructions")542			}543			trapOffset = len(bytes)544			if len(part) < 3 {545				return parsedOpcodes{}, fmt.Errorf("invalid opcodes string: invalid trap opcode")546			}547			part = part[1 : len(part)-1]548		}549		if width == 0 {550			width = len(part) / 2551		}552		number, err := strconv.ParseUint(part, 16, 64)553		if err != nil {554			return parsedOpcodes{}, fmt.Errorf("invalid opcodes string: failed to parse %#v", part)555		}556		extraBytes := make([]byte, width)557		switch len(extraBytes) {558		case 1:559			extraBytes[0] = byte(number)560		case 2:561			binaryOps.PutUint16(extraBytes, uint16(number))562		case 4:563			binaryOps.PutUint32(extraBytes, uint32(number))564		case 8:565			binaryOps.PutUint64(extraBytes, number)566		default:567			return parsedOpcodes{}, fmt.Errorf("invalid opcodes string: invalid width %v", width)568		}569		bytes = append(bytes, extraBytes...)570	}571	if trapOffset < 0 {572		return parsedOpcodes{}, fmt.Errorf("invalid opcodes string: no trapping instructions")573	}574	var flags DecompilerFlagMask575	if ctx.target.Arch == targets.ARM && width == 2 {576		flags |= FlagForceArmThumbMode577	}578	return parsedOpcodes{579		rawBytes:       bytes,580		decompileFlags: flags,581		offset:         trapOffset,582	}, nil583}584// decompileReportOpcodes detects the most meaningful "Code: " lines from the report, decompiles585// them and appends a human-readable listing to the end of the report.586func (ctx *linux) decompileReportOpcodes(report []byte) []byte {587	// Iterate over all "Code: " lines and pick the first that could be decompiled588	// that might be of interest to the user.589	var decompiled *decompiledOpcodes590	var prevLine []byte591	for s := bufio.NewScanner(bytes.NewReader(report)); s.Scan(); prevLine = append([]byte{}, s.Bytes()...) {592		// We want to avoid decompiling code from user-space as it is not of big interest during593		// debugging kernel problems.594		// For now this check only works for x86/amd64, but Linux on other architectures supported595		// by syzkaller does not seem to include user-space code in its oops messages.596		if linuxUserSegmentRe.Match(prevLine) {597			continue598		}599		match := linuxCodeRe.FindSubmatch(s.Bytes())600		if match == nil {601			continue602		}603		decompiledLine, err := ctx.processOpcodes(string(match[1]))604		if err != nil {605			continue606		}607		decompiled = decompiledLine608		break609	}610	if decompiled == nil {611		return report612	}613	skipInfo := ""614	if decompiled.leftBytesCut > 0 {615		skipInfo = fmt.Sprintf(", %v bytes skipped", decompiled.leftBytesCut)616	}617	// The decompiled instructions are intentionally put to the bottom of the report instead...

processOpcodes

Using AI Code Generation

1import (2func main() {3    f, err := os.Open("1.go")4    if err != nil {5        panic(err)6    }7    defer f.Close()8    scanner := bufio.NewScanner(f)9    for scanner.Scan() {10        fmt.Println(scanner.Text())11    }12    if err := scanner.Err(); err != nil {13        panic(err)14    }15}16import (17func main() {18    f, err := os.Open("1.go")19    if err != nil {20        panic(err)21    }22    defer f.Close()23    scanner := bufio.NewScanner(f)24    for scanner.Scan() {25        fmt.Println(scanner.Text())26    }27    if err := scanner.Err(); err != nil {28        panic(err)29    }30}

processOpcodes

Using AI Code Generation

1import (2type Report struct {3}4func (r *Report) processOpcodes() {5    for _, v := range r.opcodes {6        if v == "+" {7        } else if v == "-" {8        } else if v == "*" {9        } else if v == "/" {10        }11    }12}13func main() {14    opcodes := []string{"+", "+", "+", "-", "*", "/", "*", "/"}15    report := Report{opcodes, 0}16    report.processOpcodes()17    fmt.Println("Result: " + strconv.Itoa(report.result))18}19import (20type Report struct {21}22func (r *Report) processOpcodes() {23    for _, v := range r.opcodes {24        switch v {25        }26    }27}28func main() {29    opcodes := []string{"+", "+", "+", "-", "*", "/", "*", "/"}30    report := Report{opcodes, 0}31    report.processOpcodes()32    fmt.Println("Result: " + strconv.Itoa(report.result))33}34import (35type Report struct {36}37func (r *Report) processOpcodes() {38    for _, v := range r.opcodes {39        switch v {

processOpcodes

Using AI Code Generation

1import (2func main() {3	report := NewReport()4	csvFile, err := os.Open("input.csv")5	if err != nil {6		fmt.Println(err)7	}8	fmt.Println("Successfully Opened CSV file")9	reader := csv.NewReader(csvFile)10	records, err := reader.ReadAll()11	if err != nil {12		fmt.Println(err)13	}14	fmt.Println("Successfully Read CSV file")15	for _, row := range records {16		report.processOpcodes(row[1], row[2])17	}18	fmt.Println("Results:")19	fmt.Println("Number of times each opcode was seen:")20	fmt.Println(report.opcodeCounts)21	fmt.Println("Number of times each opcode was followed by another opcode:")22	fmt.Println(report.opcodeFollows)23}24import (25type Report struct {26}27func NewReport() *Report {28	return &Report{29		opcodeCounts:  make(map[string]int),30		opcodeFollows: make(map[string]map[string]int),31	}32}33func (r *Report) processOpcodes(opcode, opcode2 string) {34	if r.previousOpcode != "" {35		if r.opcodeFollows[r.previousOpcode] == nil {36			r.opcodeFollows[r.previousOpcode] = make(map[string]int)37		}38	}39}40import (41func main() {42	report := NewReport()

processOpcodes

Using AI Code Generation

1import (2func main() {3	r := report{}4	opcodes := []string{"A", "B", "C", "D", "E", "F", "G", "H", "I", "J"}5	r.processOpcodes(opcodes)6}7type report struct {8}9func (r report) processOpcodes(opcodes []string) {10	for _, opcode := range opcodes {11		r.processOpcode(opcode)12	}13}14func (r report) processOpcode(opcode string) {15	fmt.Println(opcode)16}17import (18func main() {19	r := report{}20	opcodes := []string{"A", "B", "C", "D", "E", "F", "G", "H", "I", "J"}21	r.processOpcodes(opcodes)22}23type report struct {24}25func (r report) processOpcodes(opcodes []string) {26	for _, opcode := range opcodes {27		r.processOpcode(opcode)28	}29}30func (r report) processOpcode(opcode string) {31	fmt.Println(opcode)32}33import (34func main() {35	r := report{}36	opcodes := []string{"A", "B", "C", "D", "E", "F", "G", "H", "I", "J"}37	r.processOpcodes(opcodes)38}39type report struct {40}

processOpcodes

Using AI Code Generation

1import "fmt"2import "github.com/udhos/gobusybox/src/busybox/report"3func main() {4    r := report.New()5    r.ProcessOpcodes()6    fmt.Println("Done")7}8import "fmt"9import "github.com/udhos/gobusybox/src/busybox/report"10func main() {11    r := report.New()12    r.ProcessOpcodes()13    fmt.Println("Done")14}15import "fmt"16import "github.com/udhos/gobusybox/src/busybox/report"17func main() {18    r := report.New()19    r.ProcessOpcodes()20    fmt.Println("Done")21}22import "fmt"23import "github.com/udhos/gobusybox/src/busybox/report"24func main() {25    r := report.New()26    r.ProcessOpcodes()27    fmt.Println("Done")28}29import "fmt"30import "github.com/udhos/gobusybox/src/busybox/report"31func main() {32    r := report.New()33    r.ProcessOpcodes()34    fmt.Println("Done")35}36import "fmt"37import "github.com/udhos/gobusybox/src/busybox/report"38func main() {39    r := report.New()40    r.ProcessOpcodes()41    fmt.Println("Done")42}43import "fmt"44import "github.com/udhos/gobusybox/src/busybox/report"45func main() {46    r := report.New()47    r.ProcessOpcodes()48    fmt.Println("Done")49}50import "fmt"51import "github.com/udhos/gobusybox/src/busybox/report"52func main() {

processOpcodes

Using AI Code Generation

1import (2func main() {3	report.processOpcodes()4}5import (6type report struct {7}8func (report *report) processOpcodes() {9	report.opcodes = []string{"a", "b", "c"}10	for _, opcode := range report.opcodes {11		fmt.Println(opcode)12	}13}

processOpcodes

Using AI Code Generation

1import "fmt"2func main() {3    r := new(report)4    r.processOpcodes()5    fmt.Println("The number of opcodes is: ", r.opcodeCount)6    fmt.Println("The number of opcodes with an operand is: ", r.opcodeWithOperandCount)7    fmt.Println("The number of opcodes with a label is: ", r.opcodeWithLabelCount)8    fmt.Println("The number of opcodes with a label and an operand is: ", r.opcodeWithLabelAndOperandCount)9}10import (11type report struct {12}13func (r *report) processOpcodes() {14}15func main() {16    data, err := ioutil.ReadFile("report.txt")17    if err != nil {18        fmt.Println("File reading error", err)19    }20    fmt.Println("Contents of file:", string(data))21}22import (23type report struct {24}25func (r *report) processOpcodes() {26}27func main() {28    data, err := ioutil.ReadFile("report.txt")29    if err != nil {30        fmt.Println("File reading error", err)31    }32    fmt.Println("Contents of file:", string(data))33}34import "fmt"35func main() {36    r := new(report)

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