Files
runc/libcontainer/integration/execin_test.go
Brian Goff 7632c4585f Fix for race from error on process start
This rather naively fixes an error observed where a processes stdio
streams are not written to when there is an error upon starting up the
process, such as when the executable doesn't exist within the
container's rootfs.

Before the "fix", when an error occurred on start, `terminate` is called
immediately, which calls `cmd.Process.Kill()`, then calling `Wait()` on
the process. In some cases when this `Kill` is called the stdio stream
have not yet been written to, causing non-deterministic output. The
error itself is properly preserved but users attached to the process
will not see this error.

With the fix it is just calling `Wait()` when an error occurs rather
than trying to `Kill()` the process first. This seems to preserve stdio.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2015-10-07 21:28:26 -04:00

389 lines
8.4 KiB
Go

package integration
import (
"bytes"
"io"
"os"
"strconv"
"strings"
"testing"
"time"
"github.com/opencontainers/runc/libcontainer"
)
func TestExecIn(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
buffers := newStdBuffers()
ps := &libcontainer.Process{
Args: []string{"ps"},
Env: standardEnvironment,
Stdin: buffers.Stdin,
Stdout: buffers.Stdout,
Stderr: buffers.Stderr,
}
err = container.Start(ps)
ok(t, err)
waitProcess(ps, t)
stdinW.Close()
waitProcess(process, t)
out := buffers.Stdout.String()
if !strings.Contains(out, "cat") || !strings.Contains(out, "ps") {
t.Fatalf("unexpected running process, output %q", out)
}
}
func TestExecInRlimit(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
buffers := newStdBuffers()
ps := &libcontainer.Process{
Args: []string{"/bin/sh", "-c", "ulimit -n"},
Env: standardEnvironment,
Stdin: buffers.Stdin,
Stdout: buffers.Stdout,
Stderr: buffers.Stderr,
}
err = container.Start(ps)
ok(t, err)
waitProcess(ps, t)
stdinW.Close()
waitProcess(process, t)
out := buffers.Stdout.String()
if limit := strings.TrimSpace(out); limit != "1025" {
t.Fatalf("expected rlimit to be 1025, got %s", limit)
}
}
func TestExecInError(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer func() {
stdinW.Close()
if _, err := process.Wait(); err != nil {
t.Log(err)
}
}()
ok(t, err)
for i := 0; i < 42; i++ {
var out bytes.Buffer
unexistent := &libcontainer.Process{
Args: []string{"unexistent"},
Env: standardEnvironment,
Stdout: &out,
}
err = container.Start(unexistent)
if err == nil {
t.Fatal("Should be an error")
}
if !strings.Contains(err.Error(), "executable file not found") {
t.Fatalf("Should be error about not found executable, got %s", err)
}
if !bytes.Contains(out.Bytes(), []byte("executable file not found")) {
t.Fatalf("executable file not found error not delivered to stdio:\n%s", out.String())
}
}
}
func TestExecInTTY(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
var stdout bytes.Buffer
ps := &libcontainer.Process{
Args: []string{"ps"},
Env: standardEnvironment,
}
console, err := ps.NewConsole(0)
copy := make(chan struct{})
go func() {
io.Copy(&stdout, console)
close(copy)
}()
ok(t, err)
err = container.Start(ps)
ok(t, err)
select {
case <-time.After(5 * time.Second):
t.Fatal("Waiting for copy timed out")
case <-copy:
}
waitProcess(ps, t)
stdinW.Close()
waitProcess(process, t)
out := stdout.String()
if !strings.Contains(out, "cat") || !strings.Contains(string(out), "ps") {
t.Fatalf("unexpected running process, output %q", out)
}
}
func TestExecInEnvironment(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
buffers := newStdBuffers()
process2 := &libcontainer.Process{
Args: []string{"env"},
Env: []string{
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"DEBUG=true",
"DEBUG=false",
"ENV=test",
},
Stdin: buffers.Stdin,
Stdout: buffers.Stdout,
Stderr: buffers.Stderr,
}
err = container.Start(process2)
ok(t, err)
waitProcess(process2, t)
stdinW.Close()
waitProcess(process, t)
out := buffers.Stdout.String()
// check execin's process environment
if !strings.Contains(out, "DEBUG=false") ||
!strings.Contains(out, "ENV=test") ||
!strings.Contains(out, "HOME=/root") ||
!strings.Contains(out, "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin") ||
strings.Contains(out, "DEBUG=true") {
t.Fatalf("unexpected running process, output %q", out)
}
}
func TestExecinPassExtraFiles(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
if err != nil {
t.Fatal(err)
}
defer remove(rootfs)
config := newTemplateConfig(rootfs)
container, err := newContainer(config)
if err != nil {
t.Fatal(err)
}
defer container.Destroy()
// Execute a first process in the container
stdinR, stdinW, err := os.Pipe()
if err != nil {
t.Fatal(err)
}
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
if err != nil {
t.Fatal(err)
}
var stdout bytes.Buffer
pipeout1, pipein1, err := os.Pipe()
pipeout2, pipein2, err := os.Pipe()
inprocess := &libcontainer.Process{
Args: []string{"sh", "-c", "cd /proc/$$/fd; echo -n *; echo -n 1 >3; echo -n 2 >4"},
Env: []string{"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"},
ExtraFiles: []*os.File{pipein1, pipein2},
Stdin: nil,
Stdout: &stdout,
}
err = container.Start(inprocess)
if err != nil {
t.Fatal(err)
}
waitProcess(inprocess, t)
stdinW.Close()
waitProcess(process, t)
out := string(stdout.Bytes())
// fd 5 is the directory handle for /proc/$$/fd
if out != "0 1 2 3 4 5" {
t.Fatalf("expected to have the file descriptors '0 1 2 3 4 5' passed to exec, got '%s'", out)
}
var buf = []byte{0}
_, err = pipeout1.Read(buf)
if err != nil {
t.Fatal(err)
}
out1 := string(buf)
if out1 != "1" {
t.Fatalf("expected first pipe to receive '1', got '%s'", out1)
}
_, err = pipeout2.Read(buf)
if err != nil {
t.Fatal(err)
}
out2 := string(buf)
if out2 != "2" {
t.Fatalf("expected second pipe to receive '2', got '%s'", out2)
}
}
func TestExecInOomScoreAdj(t *testing.T) {
if testing.Short() {
return
}
rootfs, err := newRootfs()
ok(t, err)
defer remove(rootfs)
config := newTemplateConfig(rootfs)
config.OomScoreAdj = 200
container, err := newContainer(config)
ok(t, err)
defer container.Destroy()
stdinR, stdinW, err := os.Pipe()
ok(t, err)
process := &libcontainer.Process{
Args: []string{"cat"},
Env: standardEnvironment,
Stdin: stdinR,
}
err = container.Start(process)
stdinR.Close()
defer stdinW.Close()
ok(t, err)
buffers := newStdBuffers()
ps := &libcontainer.Process{
Args: []string{"/bin/sh", "-c", "cat /proc/self/oom_score_adj"},
Env: standardEnvironment,
Stdin: buffers.Stdin,
Stdout: buffers.Stdout,
Stderr: buffers.Stderr,
}
err = container.Start(ps)
ok(t, err)
waitProcess(ps, t)
stdinW.Close()
waitProcess(process, t)
out := buffers.Stdout.String()
if oomScoreAdj := strings.TrimSpace(out); oomScoreAdj != strconv.Itoa(config.OomScoreAdj) {
t.Fatalf("expected oomScoreAdj to be %d, got %s", config.OomScoreAdj, oomScoreAdj)
}
}