diff options
Diffstat (limited to 'pkg/sentry/fsimpl/proc/tasks.go')
-rw-r--r-- | pkg/sentry/fsimpl/proc/tasks.go | 218 |
1 files changed, 0 insertions, 218 deletions
diff --git a/pkg/sentry/fsimpl/proc/tasks.go b/pkg/sentry/fsimpl/proc/tasks.go deleted file mode 100644 index d8f92d52f..000000000 --- a/pkg/sentry/fsimpl/proc/tasks.go +++ /dev/null @@ -1,218 +0,0 @@ -// 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 ( - "sort" - "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/sentry/vfs" - "gvisor.dev/gvisor/pkg/syserror" -) - -const ( - defaultPermission = 0444 - selfName = "self" - threadSelfName = "thread-self" -) - -// InoGenerator generates unique inode numbers for a given filesystem. -type InoGenerator interface { - NextIno() uint64 -} - -// tasksInode represents the inode for /proc/ directory. -// -// +stateify savable -type tasksInode struct { - kernfs.InodeNotSymlink - kernfs.InodeDirectoryNoNewChildren - kernfs.InodeAttrs - kernfs.OrderedChildren - - inoGen InoGenerator - pidns *kernel.PIDNamespace - - // '/proc/self' and '/proc/thread-self' have custom directory offsets in - // Linux. So handle them outside of OrderedChildren. - selfSymlink *vfs.Dentry - threadSelfSymlink *vfs.Dentry -} - -var _ kernfs.Inode = (*tasksInode)(nil) - -func newTasksInode(inoGen InoGenerator, k *kernel.Kernel, pidns *kernel.PIDNamespace) (*tasksInode, *kernfs.Dentry) { - root := auth.NewRootCredentials(pidns.UserNamespace()) - contents := map[string]*kernfs.Dentry{ - //"cpuinfo": newCPUInfo(ctx, msrc), - //"filesystems": seqfile.NewSeqFileInode(ctx, &filesystemsData{}, msrc), - "loadavg": newDentry(root, inoGen.NextIno(), defaultPermission, &loadavgData{}), - "meminfo": newDentry(root, inoGen.NextIno(), defaultPermission, &meminfoData{k: k}), - "mounts": kernfs.NewStaticSymlink(root, inoGen.NextIno(), defaultPermission, "self/mounts"), - "stat": newDentry(root, inoGen.NextIno(), defaultPermission, &statData{k: k}), - //"uptime": newUptime(ctx, msrc), - //"version": newVersionData(root, inoGen.NextIno(), k), - "version": newDentry(root, inoGen.NextIno(), defaultPermission, &versionData{k: k}), - } - - inode := &tasksInode{ - pidns: pidns, - inoGen: inoGen, - selfSymlink: newSelfSymlink(root, inoGen.NextIno(), 0444, pidns).VFSDentry(), - threadSelfSymlink: newThreadSelfSymlink(root, inoGen.NextIno(), 0444, pidns).VFSDentry(), - } - inode.InodeAttrs.Init(root, inoGen.NextIno(), linux.ModeDirectory|0555) - - dentry := &kernfs.Dentry{} - dentry.Init(inode) - - inode.OrderedChildren.Init(kernfs.OrderedChildrenOptions{}) - links := inode.OrderedChildren.Populate(dentry, contents) - inode.IncLinks(links) - - return inode, dentry -} - -// Lookup implements kernfs.inodeDynamicLookup. -func (i *tasksInode) Lookup(ctx context.Context, name string) (*vfs.Dentry, error) { - // Try to lookup a corresponding task. - tid, err := strconv.ParseUint(name, 10, 64) - if err != nil { - // If it failed to parse, check if it's one of the special handled files. - switch name { - case selfName: - return i.selfSymlink, nil - case threadSelfName: - return i.threadSelfSymlink, nil - } - return nil, syserror.ENOENT - } - - task := i.pidns.TaskWithID(kernel.ThreadID(tid)) - if task == nil { - return nil, syserror.ENOENT - } - - taskDentry := newTaskInode(i.inoGen, task, i.pidns, true) - return taskDentry.VFSDentry(), nil -} - -// Valid implements kernfs.inodeDynamicLookup. -func (i *tasksInode) Valid(ctx context.Context) bool { - return true -} - -// IterDirents implements kernfs.inodeDynamicLookup. -func (i *tasksInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, offset, _ int64) (int64, error) { - // fs/proc/internal.h: #define FIRST_PROCESS_ENTRY 256 - const FIRST_PROCESS_ENTRY = 256 - - // Use maxTaskID to shortcut searches that will result in 0 entries. - const maxTaskID = kernel.TasksLimit + 1 - if offset >= maxTaskID { - return offset, nil - } - - // According to Linux (fs/proc/base.c:proc_pid_readdir()), process directories - // start at offset FIRST_PROCESS_ENTRY with '/proc/self', followed by - // '/proc/thread-self' and then '/proc/[pid]'. - if offset < FIRST_PROCESS_ENTRY { - offset = FIRST_PROCESS_ENTRY - } - - if offset == FIRST_PROCESS_ENTRY { - dirent := vfs.Dirent{ - Name: selfName, - Type: linux.DT_LNK, - Ino: i.inoGen.NextIno(), - NextOff: offset + 1, - } - if !cb.Handle(dirent) { - return offset, nil - } - offset++ - } - if offset == FIRST_PROCESS_ENTRY+1 { - dirent := vfs.Dirent{ - Name: threadSelfName, - Type: linux.DT_LNK, - Ino: i.inoGen.NextIno(), - NextOff: offset + 1, - } - if !cb.Handle(dirent) { - return offset, nil - } - offset++ - } - - // Collect all tasks that TGIDs are greater than the offset specified. Per - // Linux we only include in directory listings if it's the leader. But for - // whatever crazy reason, you can still walk to the given node. - var tids []int - startTid := offset - FIRST_PROCESS_ENTRY - 2 - for _, tg := range i.pidns.ThreadGroups() { - tid := i.pidns.IDOfThreadGroup(tg) - if int64(tid) < startTid { - continue - } - if leader := tg.Leader(); leader != nil { - tids = append(tids, int(tid)) - } - } - - if len(tids) == 0 { - return offset, nil - } - - sort.Ints(tids) - for _, tid := range tids { - dirent := vfs.Dirent{ - Name: strconv.FormatUint(uint64(tid), 10), - Type: linux.DT_DIR, - Ino: i.inoGen.NextIno(), - NextOff: FIRST_PROCESS_ENTRY + 2 + int64(tid) + 1, - } - if !cb.Handle(dirent) { - return offset, nil - } - offset++ - } - return maxTaskID, nil -} - -// Open implements kernfs.Inode. -func (i *tasksInode) Open(rp *vfs.ResolvingPath, vfsd *vfs.Dentry, flags uint32) (*vfs.FileDescription, error) { - fd := &kernfs.GenericDirectoryFD{} - fd.Init(rp.Mount(), vfsd, &i.OrderedChildren, flags) - return fd.VFSFileDescription(), nil -} - -func (i *tasksInode) Stat(vsfs *vfs.Filesystem) linux.Statx { - stat := i.InodeAttrs.Stat(vsfs) - - // Add dynamic children to link count. - for _, tg := range i.pidns.ThreadGroups() { - if leader := tg.Leader(); leader != nil { - stat.Nlink++ - } - } - - return stat -} |