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-rw-r--r--fs/proc/namespaces.c3
-rw-r--r--include/linux/cgroup.h49
-rw-r--r--include/linux/nsproxy.h2
-rw-r--r--include/linux/proc_ns.h4
-rw-r--r--kernel/cgroup.c173
-rw-r--r--kernel/cpuset.c8
-rw-r--r--kernel/fork.c2
-rw-r--r--kernel/nsproxy.c19
8 files changed, 250 insertions, 10 deletions
diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c
index 276f12431dbf..72cb26f85d58 100644
--- a/fs/proc/namespaces.c
+++ b/fs/proc/namespaces.c
@@ -28,6 +28,9 @@ static const struct proc_ns_operations *ns_entries[] = {
&userns_operations,
#endif
&mntns_operations,
+#ifdef CONFIG_CGROUPS
+ &cgroupns_operations,
+#endif
};
static const char *proc_ns_get_link(struct dentry *dentry,
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 2162dca88dc0..a20320c666fd 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -17,6 +17,11 @@
#include <linux/seq_file.h>
#include <linux/kernfs.h>
#include <linux/jump_label.h>
+#include <linux/nsproxy.h>
+#include <linux/types.h>
+#include <linux/ns_common.h>
+#include <linux/nsproxy.h>
+#include <linux/user_namespace.h>
#include <linux/cgroup-defs.h>
@@ -611,4 +616,48 @@ static inline void cgroup_sk_free(struct sock_cgroup_data *skcd) {}
#endif /* CONFIG_CGROUP_DATA */
+struct cgroup_namespace {
+ atomic_t count;
+ struct ns_common ns;
+ struct user_namespace *user_ns;
+ struct css_set *root_cset;
+};
+
+extern struct cgroup_namespace init_cgroup_ns;
+
+#ifdef CONFIG_CGROUPS
+
+void free_cgroup_ns(struct cgroup_namespace *ns);
+
+struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,
+ struct user_namespace *user_ns,
+ struct cgroup_namespace *old_ns);
+
+char *cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen,
+ struct cgroup_namespace *ns);
+
+#else /* !CONFIG_CGROUPS */
+
+static inline void free_cgroup_ns(struct cgroup_namespace *ns) { }
+static inline struct cgroup_namespace *
+copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns,
+ struct cgroup_namespace *old_ns)
+{
+ return old_ns;
+}
+
+#endif /* !CONFIG_CGROUPS */
+
+static inline void get_cgroup_ns(struct cgroup_namespace *ns)
+{
+ if (ns)
+ atomic_inc(&ns->count);
+}
+
+static inline void put_cgroup_ns(struct cgroup_namespace *ns)
+{
+ if (ns && atomic_dec_and_test(&ns->count))
+ free_cgroup_ns(ns);
+}
+
#endif /* _LINUX_CGROUP_H */
diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h
index 35fa08fd7739..ac0d65bef5d0 100644
--- a/include/linux/nsproxy.h
+++ b/include/linux/nsproxy.h
@@ -8,6 +8,7 @@ struct mnt_namespace;
struct uts_namespace;
struct ipc_namespace;
struct pid_namespace;
+struct cgroup_namespace;
struct fs_struct;
/*
@@ -33,6 +34,7 @@ struct nsproxy {
struct mnt_namespace *mnt_ns;
struct pid_namespace *pid_ns_for_children;
struct net *net_ns;
+ struct cgroup_namespace *cgroup_ns;
};
extern struct nsproxy init_nsproxy;
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
index 42dfc615dbf8..de0e7719d4c5 100644
--- a/include/linux/proc_ns.h
+++ b/include/linux/proc_ns.h
@@ -9,6 +9,8 @@
struct pid_namespace;
struct nsproxy;
struct path;
+struct task_struct;
+struct inode;
struct proc_ns_operations {
const char *name;
@@ -24,6 +26,7 @@ extern const struct proc_ns_operations ipcns_operations;
extern const struct proc_ns_operations pidns_operations;
extern const struct proc_ns_operations userns_operations;
extern const struct proc_ns_operations mntns_operations;
+extern const struct proc_ns_operations cgroupns_operations;
/*
* We always define these enumerators
@@ -34,6 +37,7 @@ enum {
PROC_UTS_INIT_INO = 0xEFFFFFFEU,
PROC_USER_INIT_INO = 0xEFFFFFFDU,
PROC_PID_INIT_INO = 0xEFFFFFFCU,
+ PROC_CGROUP_INIT_INO = 0xEFFFFFFBU,
};
#ifdef CONFIG_PROC_FS
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 7ad61915967f..b001c5d36bec 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -59,6 +59,9 @@
#include <linux/delay.h>
#include <linux/atomic.h>
#include <linux/cpuset.h>
+#include <linux/proc_ns.h>
+#include <linux/nsproxy.h>
+#include <linux/proc_ns.h>
#include <net/sock.h>
/*
@@ -212,6 +215,15 @@ static unsigned long have_fork_callback __read_mostly;
static unsigned long have_exit_callback __read_mostly;
static unsigned long have_free_callback __read_mostly;
+/* cgroup namespace for init task */
+struct cgroup_namespace init_cgroup_ns = {
+ .count = { .counter = 2, },
+ .user_ns = &init_user_ns,
+ .ns.ops = &cgroupns_operations,
+ .ns.inum = PROC_CGROUP_INIT_INO,
+ .root_cset = &init_css_set,
+};
+
/* Ditto for the can_fork callback. */
static unsigned long have_canfork_callback __read_mostly;
@@ -2177,6 +2189,35 @@ static struct file_system_type cgroup2_fs_type = {
.kill_sb = cgroup_kill_sb,
};
+static char *cgroup_path_ns_locked(struct cgroup *cgrp, char *buf, size_t buflen,
+ struct cgroup_namespace *ns)
+{
+ struct cgroup *root = cset_cgroup_from_root(ns->root_cset, cgrp->root);
+ int ret;
+
+ ret = kernfs_path_from_node(cgrp->kn, root->kn, buf, buflen);
+ if (ret < 0 || ret >= buflen)
+ return NULL;
+ return buf;
+}
+
+char *cgroup_path_ns(struct cgroup *cgrp, char *buf, size_t buflen,
+ struct cgroup_namespace *ns)
+{
+ char *ret;
+
+ mutex_lock(&cgroup_mutex);
+ spin_lock_bh(&css_set_lock);
+
+ ret = cgroup_path_ns_locked(cgrp, buf, buflen, ns);
+
+ spin_unlock_bh(&css_set_lock);
+ mutex_unlock(&cgroup_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cgroup_path_ns);
+
/**
* task_cgroup_path - cgroup path of a task in the first cgroup hierarchy
* @task: target task
@@ -2204,7 +2245,7 @@ char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen)
if (root) {
cgrp = task_cgroup_from_root(task, root);
- path = cgroup_path(cgrp, buf, buflen);
+ path = cgroup_path_ns_locked(cgrp, buf, buflen, &init_cgroup_ns);
} else {
/* if no hierarchy exists, everyone is in "/" */
if (strlcpy(buf, "/", buflen) < buflen)
@@ -5297,6 +5338,8 @@ int __init cgroup_init(void)
BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files));
BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files));
+ get_user_ns(init_cgroup_ns.user_ns);
+
mutex_lock(&cgroup_mutex);
/* Add init_css_set to the hash table */
@@ -5438,7 +5481,8 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns,
* " (deleted)" is appended to the cgroup path.
*/
if (cgroup_on_dfl(cgrp) || !(tsk->flags & PF_EXITING)) {
- path = cgroup_path(cgrp, buf, PATH_MAX);
+ path = cgroup_path_ns_locked(cgrp, buf, PATH_MAX,
+ current->nsproxy->cgroup_ns);
if (!path) {
retval = -ENAMETOOLONG;
goto out_unlock;
@@ -5720,7 +5764,9 @@ static void cgroup_release_agent(struct work_struct *work)
if (!pathbuf || !agentbuf)
goto out;
- path = cgroup_path(cgrp, pathbuf, PATH_MAX);
+ spin_lock_bh(&css_set_lock);
+ path = cgroup_path_ns_locked(cgrp, pathbuf, PATH_MAX, &init_cgroup_ns);
+ spin_unlock_bh(&css_set_lock);
if (!path)
goto out;
@@ -5931,6 +5977,127 @@ void cgroup_sk_free(struct sock_cgroup_data *skcd)
#endif /* CONFIG_SOCK_CGROUP_DATA */
+/* cgroup namespaces */
+
+static struct cgroup_namespace *alloc_cgroup_ns(void)
+{
+ struct cgroup_namespace *new_ns;
+ int ret;
+
+ new_ns = kzalloc(sizeof(struct cgroup_namespace), GFP_KERNEL);
+ if (!new_ns)
+ return ERR_PTR(-ENOMEM);
+ ret = ns_alloc_inum(&new_ns->ns);
+ if (ret) {
+ kfree(new_ns);
+ return ERR_PTR(ret);
+ }
+ atomic_set(&new_ns->count, 1);
+ new_ns->ns.ops = &cgroupns_operations;
+ return new_ns;
+}
+
+void free_cgroup_ns(struct cgroup_namespace *ns)
+{
+ put_css_set(ns->root_cset);
+ put_user_ns(ns->user_ns);
+ ns_free_inum(&ns->ns);
+ kfree(ns);
+}
+EXPORT_SYMBOL(free_cgroup_ns);
+
+struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,
+ struct user_namespace *user_ns,
+ struct cgroup_namespace *old_ns)
+{
+ struct cgroup_namespace *new_ns = NULL;
+ struct css_set *cset = NULL;
+ int err;
+
+ BUG_ON(!old_ns);
+
+ if (!(flags & CLONE_NEWCGROUP)) {
+ get_cgroup_ns(old_ns);
+ return old_ns;
+ }
+
+ /* Allow only sysadmin to create cgroup namespace. */
+ err = -EPERM;
+ if (!ns_capable(user_ns, CAP_SYS_ADMIN))
+ goto err_out;
+
+ mutex_lock(&cgroup_mutex);
+ spin_lock_bh(&css_set_lock);
+
+ cset = task_css_set(current);
+ get_css_set(cset);
+
+ spin_unlock_bh(&css_set_lock);
+ mutex_unlock(&cgroup_mutex);
+
+ err = -ENOMEM;
+ new_ns = alloc_cgroup_ns();
+ if (!new_ns)
+ goto err_out;
+
+ new_ns->user_ns = get_user_ns(user_ns);
+ new_ns->root_cset = cset;
+
+ return new_ns;
+
+err_out:
+ if (cset)
+ put_css_set(cset);
+ kfree(new_ns);
+ return ERR_PTR(err);
+}
+
+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)
+{
+ pr_info("setns not supported for cgroup namespace");
+ return -EINVAL;
+}
+
+static struct ns_common *cgroupns_get(struct task_struct *task)
+{
+ struct cgroup_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ task_lock(task);
+ nsproxy = task->nsproxy;
+ if (nsproxy) {
+ ns = nsproxy->cgroup_ns;
+ get_cgroup_ns(ns);
+ }
+ task_unlock(task);
+
+ return ns ? &ns->ns : NULL;
+}
+
+static void cgroupns_put(struct ns_common *ns)
+{
+ put_cgroup_ns(to_cg_ns(ns));
+}
+
+const struct proc_ns_operations cgroupns_operations = {
+ .name = "cgroup",
+ .type = CLONE_NEWCGROUP,
+ .get = cgroupns_get,
+ .put = cgroupns_put,
+ .install = cgroupns_install,
+};
+
+static __init int cgroup_namespaces_init(void)
+{
+ return 0;
+}
+subsys_initcall(cgroup_namespaces_init);
+
#ifdef CONFIG_CGROUP_DEBUG
static struct cgroup_subsys_state *
debug_css_alloc(struct cgroup_subsys_state *parent_css)
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 41989ab4db57..d393125b228c 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2714,10 +2714,10 @@ int proc_cpuset_show(struct seq_file *m, struct pid_namespace *ns,
goto out;
retval = -ENAMETOOLONG;
- rcu_read_lock();
- css = task_css(tsk, cpuset_cgrp_id);
- p = cgroup_path(css->cgroup, buf, PATH_MAX);
- rcu_read_unlock();
+ css = task_get_css(tsk, cpuset_cgrp_id);
+ p = cgroup_path_ns(css->cgroup, buf, PATH_MAX,
+ current->nsproxy->cgroup_ns);
+ css_put(css);
if (!p)
goto out_free;
seq_puts(m, p);
diff --git a/kernel/fork.c b/kernel/fork.c
index 2e391c754ae7..6611a6267949 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1884,7 +1884,7 @@ static int check_unshare_flags(unsigned long unshare_flags)
if (unshare_flags & ~(CLONE_THREAD|CLONE_FS|CLONE_NEWNS|CLONE_SIGHAND|
CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET|
- CLONE_NEWUSER|CLONE_NEWPID))
+ CLONE_NEWUSER|CLONE_NEWPID|CLONE_NEWCGROUP))
return -EINVAL;
/*
* Not implemented, but pretend it works if there is nothing
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index 49746c81ad8d..782102e59eed 100644
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -25,6 +25,7 @@
#include <linux/proc_ns.h>
#include <linux/file.h>
#include <linux/syscalls.h>
+#include <linux/cgroup.h>
static struct kmem_cache *nsproxy_cachep;
@@ -39,6 +40,9 @@ struct nsproxy init_nsproxy = {
#ifdef CONFIG_NET
.net_ns = &init_net,
#endif
+#ifdef CONFIG_CGROUPS
+ .cgroup_ns = &init_cgroup_ns,
+#endif
};
static inline struct nsproxy *create_nsproxy(void)
@@ -92,6 +96,13 @@ static struct nsproxy *create_new_namespaces(unsigned long flags,
goto out_pid;
}
+ new_nsp->cgroup_ns = copy_cgroup_ns(flags, user_ns,
+ tsk->nsproxy->cgroup_ns);
+ if (IS_ERR(new_nsp->cgroup_ns)) {
+ err = PTR_ERR(new_nsp->cgroup_ns);
+ goto out_cgroup;
+ }
+
new_nsp->net_ns = copy_net_ns(flags, user_ns, tsk->nsproxy->net_ns);
if (IS_ERR(new_nsp->net_ns)) {
err = PTR_ERR(new_nsp->net_ns);
@@ -101,6 +112,8 @@ static struct nsproxy *create_new_namespaces(unsigned long flags,
return new_nsp;
out_net:
+ put_cgroup_ns(new_nsp->cgroup_ns);
+out_cgroup:
if (new_nsp->pid_ns_for_children)
put_pid_ns(new_nsp->pid_ns_for_children);
out_pid:
@@ -128,7 +141,8 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
struct nsproxy *new_ns;
if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
- CLONE_NEWPID | CLONE_NEWNET)))) {
+ CLONE_NEWPID | CLONE_NEWNET |
+ CLONE_NEWCGROUP)))) {
get_nsproxy(old_ns);
return 0;
}
@@ -165,6 +179,7 @@ void free_nsproxy(struct nsproxy *ns)
put_ipc_ns(ns->ipc_ns);
if (ns->pid_ns_for_children)
put_pid_ns(ns->pid_ns_for_children);
+ put_cgroup_ns(ns->cgroup_ns);
put_net(ns->net_ns);
kmem_cache_free(nsproxy_cachep, ns);
}
@@ -180,7 +195,7 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags,
int err = 0;
if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
- CLONE_NEWNET | CLONE_NEWPID)))
+ CLONE_NEWNET | CLONE_NEWPID | CLONE_NEWCGROUP)))
return 0;
user_ns = new_cred ? new_cred->user_ns : current_user_ns();