93 lines
2.4 KiB
Go
93 lines
2.4 KiB
Go
|
// Copyright 2019 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 proc
|
||
|
|
||
|
import (
|
||
|
"fmt"
|
||
|
"strconv"
|
||
|
|
||
|
"gvisor.dev/gvisor/pkg/abi/linux"
|
||
|
"gvisor.dev/gvisor/pkg/sentry/context"
|
||
|
"gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
|
||
|
"gvisor.dev/gvisor/pkg/sentry/kernel"
|
||
|
"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
|
||
|
"gvisor.dev/gvisor/pkg/syserror"
|
||
|
)
|
||
|
|
||
|
type selfSymlink struct {
|
||
|
kernfs.InodeAttrs
|
||
|
kernfs.InodeNoopRefCount
|
||
|
kernfs.InodeSymlink
|
||
|
|
||
|
pidns *kernel.PIDNamespace
|
||
|
}
|
||
|
|
||
|
var _ kernfs.Inode = (*selfSymlink)(nil)
|
||
|
|
||
|
func newSelfSymlink(creds *auth.Credentials, ino uint64, perm linux.FileMode, pidns *kernel.PIDNamespace) *kernfs.Dentry {
|
||
|
inode := &selfSymlink{pidns: pidns}
|
||
|
inode.Init(creds, ino, linux.ModeSymlink|perm)
|
||
|
|
||
|
d := &kernfs.Dentry{}
|
||
|
d.Init(inode)
|
||
|
return d
|
||
|
}
|
||
|
|
||
|
func (s *selfSymlink) Readlink(ctx context.Context) (string, error) {
|
||
|
t := kernel.TaskFromContext(ctx)
|
||
|
if t == nil {
|
||
|
// Who is reading this link?
|
||
|
return "", syserror.EINVAL
|
||
|
}
|
||
|
tgid := s.pidns.IDOfThreadGroup(t.ThreadGroup())
|
||
|
if tgid == 0 {
|
||
|
return "", syserror.ENOENT
|
||
|
}
|
||
|
return strconv.FormatUint(uint64(tgid), 10), nil
|
||
|
}
|
||
|
|
||
|
type threadSelfSymlink struct {
|
||
|
kernfs.InodeAttrs
|
||
|
kernfs.InodeNoopRefCount
|
||
|
kernfs.InodeSymlink
|
||
|
|
||
|
pidns *kernel.PIDNamespace
|
||
|
}
|
||
|
|
||
|
var _ kernfs.Inode = (*threadSelfSymlink)(nil)
|
||
|
|
||
|
func newThreadSelfSymlink(creds *auth.Credentials, ino uint64, perm linux.FileMode, pidns *kernel.PIDNamespace) *kernfs.Dentry {
|
||
|
inode := &threadSelfSymlink{pidns: pidns}
|
||
|
inode.Init(creds, ino, linux.ModeSymlink|perm)
|
||
|
|
||
|
d := &kernfs.Dentry{}
|
||
|
d.Init(inode)
|
||
|
return d
|
||
|
}
|
||
|
|
||
|
func (s *threadSelfSymlink) Readlink(ctx context.Context) (string, error) {
|
||
|
t := kernel.TaskFromContext(ctx)
|
||
|
if t == nil {
|
||
|
// Who is reading this link?
|
||
|
return "", syserror.EINVAL
|
||
|
}
|
||
|
tgid := s.pidns.IDOfThreadGroup(t.ThreadGroup())
|
||
|
tid := s.pidns.IDOfTask(t)
|
||
|
if tid == 0 || tgid == 0 {
|
||
|
return "", syserror.ENOENT
|
||
|
}
|
||
|
return fmt.Sprintf("%d/task/%d", tgid, tid), nil
|
||
|
}
|