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-rw-r--r--runsc/mitigate/cpu.go423
1 files changed, 0 insertions, 423 deletions
diff --git a/runsc/mitigate/cpu.go b/runsc/mitigate/cpu.go
deleted file mode 100644
index 4b2aa351f..000000000
--- a/runsc/mitigate/cpu.go
+++ /dev/null
@@ -1,423 +0,0 @@
-// Copyright 2021 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package mitigate
-
-import (
- "fmt"
- "io/ioutil"
- "regexp"
- "strconv"
- "strings"
-)
-
-const (
- // mds is the only bug we care about.
- mds = "mds"
-
- // Constants for parsing /proc/cpuinfo.
- processorKey = "processor"
- vendorIDKey = "vendor_id"
- cpuFamilyKey = "cpu family"
- modelKey = "model"
- physicalIDKey = "physical id"
- coreIDKey = "core id"
- bugsKey = "bugs"
-
- // Path to shutdown a CPU.
- cpuOnlineTemplate = "/sys/devices/system/cpu/cpu%d/online"
-)
-
-// cpuSet contains a map of all CPUs on the system, mapped
-// by Physical ID and CoreIDs. threads with the same
-// Core and Physical ID are Hyperthread pairs.
-type cpuSet map[cpuID]*threadGroup
-
-// newCPUSet creates a CPUSet from data read from /proc/cpuinfo.
-func newCPUSet(data []byte, vulnerable func(thread) bool) (cpuSet, error) {
- processors, err := getThreads(string(data))
- if err != nil {
- return nil, err
- }
-
- set := make(cpuSet)
- for _, p := range processors {
- // Each ID is of the form physicalID:coreID. Hyperthread pairs
- // have identical physical and core IDs. We need to match
- // Hyperthread pairs so that we can shutdown all but one per
- // pair.
- core, ok := set[p.id]
- if !ok {
- core = &threadGroup{}
- set[p.id] = core
- }
- core.isVulnerable = core.isVulnerable || vulnerable(p)
- core.threads = append(core.threads, p)
- }
- return set, nil
-}
-
-// newCPUSetFromPossible makes a cpuSet data read from
-// /sys/devices/system/cpu/possible. This is used in enable operations
-// where the caller simply wants to enable all CPUS.
-func newCPUSetFromPossible(data []byte) (cpuSet, error) {
- threads, err := getThreadsFromPossible(data)
- if err != nil {
- return nil, err
- }
-
- // We don't care if a CPU is vulnerable or not, we just
- // want to return a list of all CPUs on the host.
- set := cpuSet{
- threads[0].id: &threadGroup{
- threads: threads,
- isVulnerable: false,
- },
- }
- return set, nil
-}
-
-// String implements the String method for CPUSet.
-func (c cpuSet) String() string {
- ret := ""
- for _, tg := range c {
- ret += fmt.Sprintf("%s\n", tg)
- }
- return ret
-}
-
-// getRemainingList returns the list of threads that will remain active
-// after mitigation.
-func (c cpuSet) getRemainingList() []thread {
- threads := make([]thread, 0, len(c))
- for _, core := range c {
- // If we're vulnerable, take only one thread from the pair.
- if core.isVulnerable {
- threads = append(threads, core.threads[0])
- continue
- }
- // Otherwise don't shutdown anything.
- threads = append(threads, core.threads...)
- }
- return threads
-}
-
-// getShutdownList returns the list of threads that will be shutdown on
-// mitigation.
-func (c cpuSet) getShutdownList() []thread {
- threads := make([]thread, 0)
- for _, core := range c {
- // Only if we're vulnerable do shutdown anything. In this case,
- // shutdown all but the first entry.
- if core.isVulnerable && len(core.threads) > 1 {
- threads = append(threads, core.threads[1:]...)
- }
- }
- return threads
-}
-
-// threadGroup represents Hyperthread pairs on the same physical/core ID.
-type threadGroup struct {
- threads []thread
- isVulnerable bool
-}
-
-// String implements the String method for threadGroup.
-func (c threadGroup) String() string {
- ret := fmt.Sprintf("ThreadGroup:\nIsVulnerable: %t\n", c.isVulnerable)
- for _, processor := range c.threads {
- ret += fmt.Sprintf("%s\n", processor)
- }
- return ret
-}
-
-// getThreads returns threads structs from reading /proc/cpuinfo.
-func getThreads(data string) ([]thread, error) {
- // Each processor entry should start with the
- // processor key. Find the beginings of each.
- r := buildRegex(processorKey, `\d+`)
- indices := r.FindAllStringIndex(data, -1)
- if len(indices) < 1 {
- return nil, fmt.Errorf("no cpus found for: %q", data)
- }
-
- // Add the ending index for last entry.
- indices = append(indices, []int{len(data), -1})
-
- // Valid cpus are now defined by strings in between
- // indexes (e.g. data[index[i], index[i+1]]).
- // There should be len(indicies) - 1 CPUs
- // since the last index is the end of the string.
- cpus := make([]thread, 0, len(indices))
- // Find each string that represents a CPU. These begin "processor".
- for i := 1; i < len(indices); i++ {
- start := indices[i-1][0]
- end := indices[i][0]
- // Parse the CPU entry, which should be between start/end.
- c, err := newThread(data[start:end])
- if err != nil {
- return nil, err
- }
- cpus = append(cpus, c)
- }
- return cpus, nil
-}
-
-// getThreadsFromPossible makes threads from data read from /sys/devices/system/cpu/possible.
-func getThreadsFromPossible(data []byte) ([]thread, error) {
- possibleRegex := regexp.MustCompile(`(?m)^(\d+)(-(\d+))?$`)
- matches := possibleRegex.FindStringSubmatch(string(data))
- if len(matches) != 4 {
- return nil, fmt.Errorf("mismatch regex from %s: %q", allPossibleCPUs, string(data))
- }
-
- // If matches[3] is empty, we only have one cpu entry.
- if matches[3] == "" {
- matches[3] = matches[1]
- }
-
- begin, err := strconv.ParseInt(matches[1], 10, 64)
- if err != nil {
- return nil, fmt.Errorf("failed to parse begin: %v", err)
- }
- end, err := strconv.ParseInt(matches[3], 10, 64)
- if err != nil {
- return nil, fmt.Errorf("failed to parse end: %v", err)
- }
- if begin > end || begin < 0 || end < 0 {
- return nil, fmt.Errorf("invalid cpu bounds from possible: begin: %d end: %d", begin, end)
- }
-
- ret := make([]thread, 0, end-begin)
- for i := begin; i <= end; i++ {
- ret = append(ret, thread{
- processorNumber: i,
- id: cpuID{
- physicalID: 0, // we don't care about id for enable ops.
- coreID: 0,
- },
- })
- }
-
- return ret, nil
-}
-
-// cpuID for each thread is defined by the physical and
-// core IDs. If equal, two threads are Hyperthread pairs.
-type cpuID struct {
- physicalID int64
- coreID int64
-}
-
-// type cpu represents pertinent info about a cpu.
-type thread struct {
- processorNumber int64 // the processor number of this CPU.
- vendorID string // the vendorID of CPU (e.g. AuthenticAMD).
- cpuFamily int64 // CPU family number (e.g. 6 for CascadeLake/Skylake).
- model int64 // CPU model number (e.g. 85 for CascadeLake/Skylake).
- id cpuID // id for this thread
- bugs map[string]struct{} // map of vulnerabilities parsed from the 'bugs' field.
-}
-
-// newThread parses a CPU from a single cpu entry from /proc/cpuinfo.
-func newThread(data string) (thread, error) {
- empty := thread{}
- processor, err := parseProcessor(data)
- if err != nil {
- return empty, err
- }
-
- vendorID, err := parseVendorID(data)
- if err != nil {
- return empty, err
- }
-
- cpuFamily, err := parseCPUFamily(data)
- if err != nil {
- return empty, err
- }
-
- model, err := parseModel(data)
- if err != nil {
- return empty, err
- }
-
- physicalID, err := parsePhysicalID(data)
- if err != nil {
- return empty, err
- }
-
- coreID, err := parseCoreID(data)
- if err != nil {
- return empty, err
- }
-
- bugs, err := parseBugs(data)
- if err != nil {
- return empty, err
- }
-
- return thread{
- processorNumber: processor,
- vendorID: vendorID,
- cpuFamily: cpuFamily,
- model: model,
- id: cpuID{
- physicalID: physicalID,
- coreID: coreID,
- },
- bugs: bugs,
- }, nil
-}
-
-// String implements the String method for thread.
-func (t thread) String() string {
- template := `CPU: %d
-CPU ID: %+v
-Vendor: %s
-Family/Model: %d/%d
-Bugs: %s
-`
- bugs := make([]string, 0)
- for bug := range t.bugs {
- bugs = append(bugs, bug)
- }
-
- return fmt.Sprintf(template, t.processorNumber, t.id, t.vendorID, t.cpuFamily, t.model, strings.Join(bugs, ","))
-}
-
-// enable turns on the CPU by writing 1 to /sys/devices/cpu/cpu{N}/online.
-func (t thread) enable() error {
- cpuPath := fmt.Sprintf(cpuOnlineTemplate, t.processorNumber)
- return ioutil.WriteFile(cpuPath, []byte{'1'}, 0644)
-}
-
-// disable turns off the CPU by writing 0 to /sys/devices/cpu/cpu{N}/online.
-func (t thread) disable() error {
- cpuPath := fmt.Sprintf(cpuOnlineTemplate, t.processorNumber)
- return ioutil.WriteFile(cpuPath, []byte{'0'}, 0644)
-}
-
-// isVulnerable checks if a CPU is vulnerable to mds.
-func (t thread) isVulnerable() bool {
- _, ok := t.bugs[mds]
- return ok
-}
-
-// isActive checks if a CPU is active from /sys/devices/system/cpu/cpu{N}/online
-// If the file does not exist (ioutil returns in error), we assume the CPU is on.
-func (t thread) isActive() bool {
- cpuPath := fmt.Sprintf(cpuOnlineTemplate, t.processorNumber)
- data, err := ioutil.ReadFile(cpuPath)
- if err != nil {
- return true
- }
- return len(data) > 0 && data[0] != '0'
-}
-
-// similarTo checks family/model/bugs fields for equality of two
-// processors.
-func (t thread) similarTo(other thread) bool {
- if t.vendorID != other.vendorID {
- return false
- }
-
- if other.cpuFamily != t.cpuFamily {
- return false
- }
-
- if other.model != t.model {
- return false
- }
-
- if len(other.bugs) != len(t.bugs) {
- return false
- }
-
- for bug := range t.bugs {
- if _, ok := other.bugs[bug]; !ok {
- return false
- }
- }
- return true
-}
-
-// parseProcessor grabs the processor field from /proc/cpuinfo output.
-func parseProcessor(data string) (int64, error) {
- return parseIntegerResult(data, processorKey)
-}
-
-// parseVendorID grabs the vendor_id field from /proc/cpuinfo output.
-func parseVendorID(data string) (string, error) {
- return parseRegex(data, vendorIDKey, `[\w\d]+`)
-}
-
-// parseCPUFamily grabs the cpu family field from /proc/cpuinfo output.
-func parseCPUFamily(data string) (int64, error) {
- return parseIntegerResult(data, cpuFamilyKey)
-}
-
-// parseModel grabs the model field from /proc/cpuinfo output.
-func parseModel(data string) (int64, error) {
- return parseIntegerResult(data, modelKey)
-}
-
-// parsePhysicalID parses the physical id field.
-func parsePhysicalID(data string) (int64, error) {
- return parseIntegerResult(data, physicalIDKey)
-}
-
-// parseCoreID parses the core id field.
-func parseCoreID(data string) (int64, error) {
- return parseIntegerResult(data, coreIDKey)
-}
-
-// parseBugs grabs the bugs field from /proc/cpuinfo output.
-func parseBugs(data string) (map[string]struct{}, error) {
- result, err := parseRegex(data, bugsKey, `[\d\w\s]*`)
- if err != nil {
- return nil, err
- }
- bugs := strings.Split(result, " ")
- ret := make(map[string]struct{}, len(bugs))
- for _, bug := range bugs {
- ret[bug] = struct{}{}
- }
- return ret, nil
-}
-
-// parseIntegerResult parses fields expecting an integer.
-func parseIntegerResult(data, key string) (int64, error) {
- result, err := parseRegex(data, key, `\d+`)
- if err != nil {
- return 0, err
- }
- return strconv.ParseInt(result, 0, 64)
-}
-
-// buildRegex builds a regex for parsing each CPU field.
-func buildRegex(key, match string) *regexp.Regexp {
- reg := fmt.Sprintf(`(?m)^%s\s*:\s*(.*)$`, key)
- return regexp.MustCompile(reg)
-}
-
-// parseRegex parses data with key inserted into a standard regex template.
-func parseRegex(data, key, match string) (string, error) {
- r := buildRegex(key, match)
- matches := r.FindStringSubmatch(data)
- if len(matches) < 2 {
- return "", fmt.Errorf("failed to match key %q: %q", key, data)
- }
- return matches[1], nil
-}