From a0530e087e648263f81a81d62ca020f66b54bcb0 Mon Sep 17 00:00:00 2001 From: Aditya Kali Date: Fri, 29 Jan 2016 02:54:07 -0600 Subject: cgroup: cgroup namespace setns support 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 Signed-off-by: Serge E. Hallyn Signed-off-by: Tejun Heo --- kernel/cgroup.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'kernel') diff --git a/kernel/cgroup.c b/kernel/cgroup.c index b001c5d36bec..b086a461be23 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -6057,10 +6057,23 @@ static inline struct cgroup_namespace *to_cg_ns(struct ns_common *ns) return container_of(ns, struct cgroup_namespace, ns); } -static int cgroupns_install(struct nsproxy *nsproxy, void *ns) +static int cgroupns_install(struct nsproxy *nsproxy, struct ns_common *ns) { - pr_info("setns not supported for cgroup namespace"); - return -EINVAL; + 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) -- cgit v1.2.3