diff options
Diffstat (limited to 'pkg/sentry/fsimpl/proc/task.go')
| -rw-r--r-- | pkg/sentry/fsimpl/proc/task.go | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go index 621c17cfe..a0580f20d 100644 --- a/pkg/sentry/fsimpl/proc/task.go +++ b/pkg/sentry/fsimpl/proc/task.go @@ -15,6 +15,7 @@ package proc import ( + "bytes" "fmt" "gvisor.dev/gvisor/pkg/abi/linux" @@ -42,7 +43,7 @@ type taskInode struct { var _ kernfs.Inode = (*taskInode)(nil) -func newTaskInode(inoGen InoGenerator, task *kernel.Task, pidns *kernel.PIDNamespace, isThreadGroup bool) *kernfs.Dentry { +func newTaskInode(inoGen InoGenerator, task *kernel.Task, pidns *kernel.PIDNamespace, isThreadGroup bool, cgroupControllers map[string]string) *kernfs.Dentry { contents := map[string]*kernfs.Dentry{ "auxv": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &auxvData{task: task}), "cmdline": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &cmdlineData{task: task, arg: cmdlineDataArg}), @@ -68,11 +69,11 @@ func newTaskInode(inoGen InoGenerator, task *kernel.Task, pidns *kernel.PIDNames "uid_map": newTaskOwnedFile(task, inoGen.NextIno(), 0644, &idMapData{task: task, gids: false}), } if isThreadGroup { - contents["task"] = newSubtasks(task, pidns, inoGen) + contents["task"] = newSubtasks(task, pidns, inoGen, cgroupControllers) + } + if len(cgroupControllers) > 0 { + contents["cgroup"] = newTaskOwnedFile(task, inoGen.NextIno(), 0444, newCgroupData(cgroupControllers)) } - //if len(p.cgroupControllers) > 0 { - // contents["cgroup"] = newCGroupInode(t, msrc, p.cgroupControllers) - //} taskInode := &taskInode{task: task} // Note: credentials are overridden by taskOwnedInode. @@ -227,3 +228,22 @@ func newNamespaceSymlink(task *kernel.Task, ino uint64, ns string) *kernfs.Dentr d.Init(taskInode) return d } + +// newCgroupData creates inode that shows cgroup information. +// From man 7 cgroups: "For each cgroup hierarchy of which the process is a +// member, there is one entry containing three colon-separated fields: +// hierarchy-ID:controller-list:cgroup-path" +func newCgroupData(controllers map[string]string) dynamicInode { + buf := bytes.Buffer{} + + // The hierarchy ids must be positive integers (for cgroup v1), but the + // exact number does not matter, so long as they are unique. We can + // just use a counter, but since linux sorts this file in descending + // order, we must count down to preserve this behavior. + i := len(controllers) + for name, dir := range controllers { + fmt.Fprintf(&buf, "%d:%s:%s\n", i, name, dir) + i-- + } + return newStaticFile(buf.String()) +} |