shimv2: remove use containerd ns as netns

```
//the network namespace created by cni plugin
netns, err = namespaces.NamespaceRequired(ctx)
if err != nil {
        return nil, errors.Wrap(err, "create namespace")
}
```

the netns is a containerd namespace concept, it not netns, event a cni
set netns for this, this is a tricky way, so remove the logic.

Fixes: kata-containers#1692

Signed-off-by: Ace-Tang <[email protected]>

containerd-shim-v2/create.go

@@ -10,12 +10,13 @@ package containerdshim
 import (
 	"context"
 	"fmt"
+	"os"
+	"path/filepath"
+
 	"github.com/containerd/typeurl"
 	vc "github.com/kata-containers/runtime/virtcontainers"
 	"github.com/kata-containers/runtime/virtcontainers/pkg/oci"
 	"github.com/pkg/errors"
-	"os"
-	"path/filepath"
 
 	taskAPI "github.com/containerd/containerd/runtime/v2/task"
 
@@ -30,7 +31,7 @@ import (
 	crioption "github.com/containerd/cri-containerd/pkg/api/runtimeoptions/v1"
 )
 
-func create(ctx context.Context, s *service, r *taskAPI.CreateTaskRequest, netns string) (*container, error) {
+func create(ctx context.Context, s *service, r *taskAPI.CreateTaskRequest) (*container, error) {
 	rootFs := vc.RootFs{Mounted: s.mount}
 	if len(r.Rootfs) == 1 {
 		m := r.Rootfs[0]
@@ -40,7 +41,7 @@ func create(ctx context.Context, s *service, r *taskAPI.CreateTaskRequest, netns
 	}
 
 	detach := !r.Terminal
-	ociSpec, bundlePath, err := loadSpec(r, netns)
+	ociSpec, bundlePath, err := loadSpec(r)
 	if err != nil {
 		return nil, err
 	}
@@ -124,7 +125,7 @@ func create(ctx context.Context, s *service, r *taskAPI.CreateTaskRequest, netns
 	return container, nil
 }
 
-func loadSpec(r *taskAPI.CreateTaskRequest, netns string) (*oci.CompatOCISpec, string, error) {
+func loadSpec(r *taskAPI.CreateTaskRequest) (*oci.CompatOCISpec, string, error) {
 	// Checks the MUST and MUST NOT from OCI runtime specification
 	bundlePath, err := validBundle(r.ID, r.Bundle)
 	if err != nil {
@@ -136,23 +137,6 @@ func loadSpec(r *taskAPI.CreateTaskRequest, netns string) (*oci.CompatOCISpec, s
 		return nil, "", err
 	}
 
-	//set the network namespace path
-	//this set will be applied to sandbox's
-	//network config and has nothing to
-	//do with containers in the sandbox since
-	//networkNamespace has been ignored by
-	//kata-agent in sandbox.
-
-	for _, n := range ociSpec.Linux.Namespaces {
-		if n.Type != specs.NetworkNamespace {
-			continue
-		}
-
-		if n.Path == "" {
-			n.Path = netns
-		}
-	}
-
 	// Todo:
 	// Since there is a bug in kata for sharedPidNs, here to
 	// remove the pidns to disable the sharePidNs temporarily,

containerd-shim-v2/service.go

@@ -334,15 +334,8 @@ func (s *service) Create(ctx context.Context, r *taskAPI.CreateTaskRequest) (_ *
 	defer s.mu.Unlock()
 
 	var c *container
-	var netns string
 
-	//the network namespace created by cni plugin
-	netns, err = namespaces.NamespaceRequired(ctx)
-	if err != nil {
-		return nil, errors.Wrap(err, "create namespace")
-	}
-
-	c, err = create(ctx, s, r, netns)
+	c, err = create(ctx, s, r)
 	if err != nil {
 		return nil, err
 	}