0ct0pu5/moby
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

libnetwork: create netns without reexec

Browse source 
Signed-off-by: Cory Snider <csnider@mirantis.com>
This commit is contained in:
Cory Snider 2022-10-18 13:51:50 -04:00
parent ffb2c1fb4a
commit 0246332954
1 changed files with 5 additions and 25 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
libnetwork/osl/namespace_linux.go
View file

@ -14,6 +14,7 @@ import (
"syscall"
"time"
"github.com/docker/docker/internal/unshare"
"github.com/docker/docker/libnetwork/ns"
"github.com/docker/docker/libnetwork/osl/kernel"
"github.com/docker/docker/libnetwork/types"
@ -70,10 +71,6 @@ func SetBasePath(path string) {
prefix = path
}
func init() {
reexec.Register("netns-create", reexecCreateNamespace)
}
func basePath() string {
return filepath.Join(prefix, "netns")
}
@ -301,35 +298,18 @@ func GetSandboxForExternalKey(basePath string, key string) (Sandbox, error) {
return n, nil
}
func reexecCreateNamespace() {
if len(os.Args) < 2 {
logrus.Fatal("no namespace path provided")
}
if err := mountNetworkNamespace("/proc/self/ns/net", os.Args[1]); err != nil {
logrus.Fatal(err)
}
}
func createNetworkNamespace(path string, osCreate bool) error {
if err := createNamespaceFile(path); err != nil {
return err
}
cmd := &exec.Cmd{
Path: reexec.Self(),
Args: append([]string{"netns-create"}, path),
Stdout: os.Stdout,
Stderr: os.Stderr,
do := func() error {
return mountNetworkNamespace(fmt.Sprintf("/proc/self/task/%d/ns/net", unix.Gettid()), path)
}
if osCreate {
cmd.SysProcAttr = &syscall.SysProcAttr{}
cmd.SysProcAttr.Cloneflags = syscall.CLONE_NEWNET
return unshare.Go(unix.CLONE_NEWNET, do, nil)
}
if err := cmd.Run(); err != nil {
return fmt.Errorf("namespace creation reexec command failed: %v", err)
}
return nil
return do()
}
func unmountNamespaceFile(path string) {