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-rw-r--r--runsc/mitigate/mitigate.go286
-rw-r--r--runsc/mitigate/mock.go145
2 files changed, 202 insertions, 229 deletions
diff --git a/runsc/mitigate/mitigate.go b/runsc/mitigate/mitigate.go
index 9f29ec873..00e5bf2a9 100644
--- a/runsc/mitigate/mitigate.go
+++ b/runsc/mitigate/mitigate.go
@@ -19,10 +19,7 @@ package mitigate
import (
"fmt"
- "io/ioutil"
- "os"
"regexp"
- "sort"
"strconv"
"strings"
)
@@ -39,128 +36,20 @@ const (
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[threadID]*ThreadGroup
+type CPUSet []*CPU
// NewCPUSet creates a CPUSet from data read from /proc/cpuinfo.
-func NewCPUSet(data []byte) (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 || p.IsVulnerable()
- core.threads = append(core.threads, p)
- }
-
- // We need to make sure we shutdown the lowest number processor per
- // thread group.
- for _, tg := range set {
- sort.Slice(tg.threads, func(i, j int) bool {
- return tg.threads[i].processorNumber < tg.threads[j].processorNumber
- })
- }
- 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) {
+func NewCPUSet(data string) (CPUSet, error) {
// Each processor entry should start with the
// processor key. Find the beginings of each.
r := buildRegex(processorKey)
indices := r.FindAllStringIndex(data, -1)
+
if len(indices) < 1 {
return nil, fmt.Errorf("no cpus found for: %q", data)
}
@@ -172,193 +61,132 @@ func getThreads(data string) ([]Thread, error) {
// 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))
+ var set CPUSet
// 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])
+ c, err := newCPU(data[start:end])
if err != nil {
return nil, err
}
- cpus = append(cpus, c)
+ set = append(set, c)
}
- return cpus, nil
+ return set, 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 possible: %q", 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: threadID{
- physicalID: 0, // we don't care about id for enable ops.
- coreID: 0,
- },
- })
+// IsVulnerable checks if this CPUSet is vulnerable to MDS.
+func (c CPUSet) IsVulnerable() bool {
+ for _, cpu := range c {
+ if cpu.IsVulnerable() {
+ return true
+ }
}
-
- return ret, nil
+ return false
}
-// threadID for each thread is defined by the physical and
-// core IDs. If equal, two threads are Hyperthread pairs.
-type threadID struct {
- physicalID int64
- coreID int64
+// String implements the String method for CPUSet.
+func (c CPUSet) String() string {
+ parts := make([]string, len(c))
+ for i, cpu := range c {
+ parts[i] = cpu.String()
+ }
+ return strings.Join(parts, "\n")
}
-// Thread represents pertinent info about a single hyperthread in a pair.
-type Thread struct {
+// CPU represents pertinent info about a single hyperthread in a pair.
+type CPU 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 threadID // id for this thread
+ physicalID int64 // Physical ID of this CPU.
+ coreID int64 // Core ID of this CPU.
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{}
+func newCPU(data string) (*CPU, error) {
processor, err := parseProcessor(data)
if err != nil {
- return empty, err
+ return nil, err
}
vendorID, err := parseVendorID(data)
if err != nil {
- return empty, err
+ return nil, err
}
cpuFamily, err := parseCPUFamily(data)
if err != nil {
- return empty, err
+ return nil, err
}
model, err := parseModel(data)
if err != nil {
- return empty, err
+ return nil, err
}
physicalID, err := parsePhysicalID(data)
if err != nil {
- return empty, err
+ return nil, err
}
coreID, err := parseCoreID(data)
if err != nil {
- return empty, err
+ return nil, err
}
bugs, err := parseBugs(data)
if err != nil {
- return empty, err
+ return nil, err
}
- return Thread{
+ return &CPU{
processorNumber: processor,
vendorID: vendorID,
cpuFamily: cpuFamily,
model: model,
- id: threadID{
- physicalID: physicalID,
- coreID: coreID,
- },
- bugs: bugs,
+ 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
+// String implements the String method for CPU.
+func (t *CPU) String() string {
+ template := `%s: %d
+%s: %s
+%s: %d
+%s: %d
+%s: %d
+%s: %d
+%s: %s
`
- bugs := make([]string, 0)
+ var bugs []string
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 {
- // Linux ensures that "cpu0" is always online.
- if t.processorNumber == 0 {
- return nil
- }
- cpuPath := fmt.Sprintf(cpuOnlineTemplate, t.processorNumber)
- f, err := os.OpenFile(cpuPath, os.O_WRONLY|os.O_CREATE, 0644)
- if err != nil {
- return fmt.Errorf("failed to open file %s: %v", cpuPath, err)
- }
- if _, err = f.Write([]byte{'1'}); err != nil {
- return fmt.Errorf("failed to write '1' to %s: %v", cpuPath, err)
- }
- return nil
-}
-
-// Disable turns off the CPU by writing 0 to /sys/devices/cpu/cpu{N}/online.
-func (t Thread) Disable() error {
- // The core labeled "cpu0" can never be taken offline via this method.
- // Linux will return EPERM if the user even creates a file at the /sys
- // path above.
- if t.processorNumber == 0 {
- return fmt.Errorf("invalid shutdown operation: cpu0 cannot be disabled")
- }
- cpuPath := fmt.Sprintf(cpuOnlineTemplate, t.processorNumber)
- return ioutil.WriteFile(cpuPath, []byte{'0'}, 0644)
+ return fmt.Sprintf(template,
+ processorKey, t.processorNumber,
+ vendorIDKey, t.vendorID,
+ cpuFamilyKey, t.cpuFamily,
+ modelKey, t.model,
+ physicalIDKey, t.physicalID,
+ coreIDKey, t.coreID,
+ bugsKey, strings.Join(bugs, " "))
}
// IsVulnerable checks if a CPU is vulnerable to mds.
-func (t Thread) IsVulnerable() bool {
+func (t *CPU) 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 {
+func (t *CPU) SimilarTo(other *CPU) bool {
if t.vendorID != other.vendorID {
return false
}
diff --git a/runsc/mitigate/mock.go b/runsc/mitigate/mock.go
new file mode 100644
index 000000000..4588ae2ed
--- /dev/null
+++ b/runsc/mitigate/mock.go
@@ -0,0 +1,145 @@
+// 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 "strings"
+
+// MockCPU represents data from CPUs that will be mitigated.
+type MockCPU struct {
+ Name string
+ VendorID string
+ Family int64
+ Model int64
+ ModelName string
+ Bugs string
+ PhysicalCores int64
+ Cores int64
+ ThreadsPerCore int64
+}
+
+// CascadeLake2 is a two core Intel CascadeLake machine.
+var CascadeLake2 = MockCPU{
+ Name: "CascadeLake",
+ VendorID: "GenuineIntel",
+ Family: 6,
+ Model: 85,
+ ModelName: "Intel(R) Xeon(R) CPU",
+ Bugs: "spectre_v1 spectre_v2 spec_store_bypass mds swapgs taa",
+ PhysicalCores: 1,
+ Cores: 1,
+ ThreadsPerCore: 2,
+}
+
+// CascadeLake4 is a four core Intel CascadeLake machine.
+var CascadeLake4 = MockCPU{
+ Name: "CascadeLake",
+ VendorID: "GenuineIntel",
+ Family: 6,
+ Model: 85,
+ ModelName: "Intel(R) Xeon(R) CPU",
+ Bugs: "spectre_v1 spectre_v2 spec_store_bypass mds swapgs taa",
+ PhysicalCores: 1,
+ Cores: 2,
+ ThreadsPerCore: 2,
+}
+
+// Haswell2 is a two core Intel Haswell machine.
+var Haswell2 = MockCPU{
+ Name: "Haswell",
+ VendorID: "GenuineIntel",
+ Family: 6,
+ Model: 63,
+ ModelName: "Intel(R) Xeon(R) CPU",
+ Bugs: "cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs",
+ PhysicalCores: 1,
+ Cores: 1,
+ ThreadsPerCore: 2,
+}
+
+// Haswell2core is a 2 core Intel Haswell machine with no hyperthread pairs.
+var Haswell2core = MockCPU{
+ Name: "Haswell2Physical",
+ VendorID: "GenuineIntel",
+ Family: 6,
+ Model: 63,
+ ModelName: "Intel(R) Xeon(R) CPU",
+ Bugs: "cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs",
+ PhysicalCores: 2,
+ Cores: 1,
+ ThreadsPerCore: 1,
+}
+
+// AMD2 is an two core AMD machine.
+var AMD2 = MockCPU{
+ Name: "AMD",
+ VendorID: "AuthenticAMD",
+ Family: 23,
+ Model: 49,
+ ModelName: "AMD EPYC 7B12",
+ Bugs: "sysret_ss_attrs spectre_v1 spectre_v2 spec_store_bypass",
+ PhysicalCores: 1,
+ Cores: 1,
+ ThreadsPerCore: 2,
+}
+
+// AMD8 is an eight core AMD machine.
+var AMD8 = MockCPU{
+ Name: "AMD",
+ VendorID: "AuthenticAMD",
+ Family: 23,
+ Model: 49,
+ ModelName: "AMD EPYC 7B12",
+ Bugs: "sysret_ss_attrs spectre_v1 spectre_v2 spec_store_bypass",
+ PhysicalCores: 4,
+ Cores: 1,
+ ThreadsPerCore: 2,
+}
+
+// Empty is an empty CPU set.
+var Empty = MockCPU{
+ Name: "Empty",
+}
+
+// MakeCPUSet makes a cpuSet from a MockCPU.
+func (tc MockCPU) MakeCPUSet() CPUSet {
+ bugs := make(map[string]struct{})
+ for _, bug := range strings.Split(tc.Bugs, " ") {
+ bugs[bug] = struct{}{}
+ }
+ var cpus CPUSet = []*CPU{}
+ for i := int64(0); i < tc.PhysicalCores; i++ {
+ for j := int64(0); j < tc.Cores; j++ {
+ for k := int64(0); k < tc.ThreadsPerCore; k++ {
+ processorNum := (i*tc.Cores+j)*tc.ThreadsPerCore + k
+ cpu := &CPU{
+ processorNumber: processorNum,
+ vendorID: tc.VendorID,
+ cpuFamily: tc.Family,
+ model: tc.Model,
+ physicalID: i,
+ coreID: j,
+ bugs: bugs,
+ }
+ cpus = append(cpus, cpu)
+ }
+ }
+ }
+ return cpus
+}
+
+// NumCPUs returns the number of CPUs for this CPU.
+func (tc MockCPU) NumCPUs() int {
+ return int(tc.PhysicalCores * tc.Cores * tc.ThreadsPerCore)
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 21:51:42 +0000