From 0b57e77d7c1c54706611c9ca15e352425adb05e5 Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Mon, 8 Jul 2019 13:11:18 +0200
Subject: libpod: support for cgroup namespace

allow a container to run in a new cgroup namespace.

When running in a new cgroup namespace, the current cgroup appears to
be the root, so that there is no way for the container to access
cgroups outside of its own subtree.

By default it uses --cgroup=host to keep the previous behavior.

To create a new namespace, --cgroup=private must be provided.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
---
 cmd/podman/common.go              |  4 ++++
 cmd/podman/shared/create.go       | 18 +++++++++++++-----
 cmd/podman/shared/intermediate.go |  1 +
 3 files changed, 18 insertions(+), 5 deletions(-)

(limited to 'cmd')

diff --git a/cmd/podman/common.go b/cmd/podman/common.go
index 15f753d55..1e9092bd6 100644
--- a/cmd/podman/common.go
+++ b/cmd/podman/common.go
@@ -129,6 +129,10 @@ func getCreateFlags(c *cliconfig.PodmanCommand) {
 		"cap-drop", []string{},
 		"Drop capabilities from the container",
 	)
+	createFlags.String(
+		"cgroupns", "host",
+		"cgroup namespace to use",
+	)
 	createFlags.String(
 		"cgroup-parent", "",
 		"Optional parent cgroup for the container",
diff --git a/cmd/podman/shared/create.go b/cmd/podman/shared/create.go
index 5c37a1875..b14ce431d 100644
--- a/cmd/podman/shared/create.go
+++ b/cmd/podman/shared/create.go
@@ -400,11 +400,12 @@ func ParseCreateOpts(ctx context.Context, c *GenericCLIResults, runtime *libpod.
 		namespaceNet = c.String("net")
 	}
 	namespaces = map[string]string{
-		"pid":  c.String("pid"),
-		"net":  namespaceNet,
-		"ipc":  c.String("ipc"),
-		"user": c.String("userns"),
-		"uts":  c.String("uts"),
+		"cgroup": c.String("cgroupns"),
+		"pid":    c.String("pid"),
+		"net":    namespaceNet,
+		"ipc":    c.String("ipc"),
+		"user":   c.String("userns"),
+		"uts":    c.String("uts"),
 	}
 
 	originalPodName := c.String("pod")
@@ -462,6 +463,11 @@ func ParseCreateOpts(ctx context.Context, c *GenericCLIResults, runtime *libpod.
 		return nil, errors.Errorf("--uts %q is not valid", namespaces["uts"])
 	}
 
+	cgroupMode := ns.CgroupMode(namespaces["cgroup"])
+	if !cgroupMode.Valid() {
+		return nil, errors.Errorf("--cgroup %q is not valid", namespaces["cgroup"])
+	}
+
 	ipcMode := ns.IpcMode(namespaces["ipc"])
 	if !cc.Valid(string(ipcMode), ipcMode) {
 		return nil, errors.Errorf("--ipc %q is not valid", ipcMode)
@@ -652,6 +658,7 @@ func ParseCreateOpts(ctx context.Context, c *GenericCLIResults, runtime *libpod.
 		CapAdd:            c.StringSlice("cap-add"),
 		CapDrop:           c.StringSlice("cap-drop"),
 		CidFile:           c.String("cidfile"),
+		Cgroupns:          c.String("cgroupns"),
 		CgroupParent:      c.String("cgroup-parent"),
 		Command:           command,
 		Detach:            c.Bool("detach"),
@@ -687,6 +694,7 @@ func ParseCreateOpts(ctx context.Context, c *GenericCLIResults, runtime *libpod.
 		NetMode:        netMode,
 		UtsMode:        utsMode,
 		PidMode:        pidMode,
+		CgroupMode:     cgroupMode,
 		Pod:            podName,
 		Privileged:     c.Bool("privileged"),
 		Publish:        c.StringSlice("publish"),
diff --git a/cmd/podman/shared/intermediate.go b/cmd/podman/shared/intermediate.go
index 8337dc647..4062ac48a 100644
--- a/cmd/podman/shared/intermediate.go
+++ b/cmd/podman/shared/intermediate.go
@@ -370,6 +370,7 @@ func NewIntermediateLayer(c *cliconfig.PodmanCommand, remote bool) GenericCLIRes
 	m["blkio-weight-device"] = newCRStringSlice(c, "blkio-weight-device")
 	m["cap-add"] = newCRStringSlice(c, "cap-add")
 	m["cap-drop"] = newCRStringSlice(c, "cap-drop")
+	m["cgroupns"] = newCRString(c, "cgroupns")
 	m["cgroup-parent"] = newCRString(c, "cgroup-parent")
 	m["cidfile"] = newCRString(c, "cidfile")
 	m["conmon-pidfile"] = newCRString(c, "conmon-pidfile")
-- 
cgit v1.2.3-54-g00ecf