[PATCH 4/8] cgroup: cgroup namespace setns support
From: <hidden>
Date: 2015-12-09 19:29:10
Also in:
cgroups, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Aditya Kali <redacted> setns on a cgroup namespace is allowed only if task has CAP_SYS_ADMIN in its current user-namespace and over the user-namespace associated with target cgroupns. No implicit cgroup changes happen with attaching to another cgroupns. It is expected that the somone moves the attaching process under the target cgroupns-root. Signed-off-by: Aditya Kali <redacted> Signed-off-by: Serge E. Hallyn <redacted> --- kernel/cgroup.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 92db64c..f34551a 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c@@ -5904,10 +5904,28 @@ err_out: return ERR_PTR(err); } -static int cgroupns_install(struct nsproxy *nsproxy, void *ns) +static inline struct cgroup_namespace *to_cg_ns(struct ns_common *ns) { - pr_info("setns not supported for cgroup namespace"); - return -EINVAL; + return container_of(ns, struct cgroup_namespace, ns); +} + +static int cgroupns_install(struct nsproxy *nsproxy, struct ns_common *ns) +{ + struct cgroup_namespace *cgroup_ns = to_cg_ns(ns); + + if (!ns_capable(current_user_ns(), CAP_SYS_ADMIN) || + !ns_capable(cgroup_ns->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + + /* Don't need to do anything if we are attaching to our own cgroupns. */ + if (cgroup_ns == nsproxy->cgroup_ns) + return 0; + + get_cgroup_ns(cgroup_ns); + put_cgroup_ns(nsproxy->cgroup_ns); + nsproxy->cgroup_ns = cgroup_ns; + + return 0; } static struct ns_common *cgroupns_get(struct task_struct *task)
--
1.7.9.5