8 files changed, 51 insertions, 4 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index a4414a11eea7..440a72164a11 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -644,6 +644,7 @@ struct cgroup_namespace {
 	atomic_t		count;
 	struct ns_common	ns;
 	struct user_namespace	*user_ns;
+	struct ucounts		*ucounts;
 	struct css_set          *root_cset;
 };
 
diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
index d10e54f03c09..848e5796400e 100644
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -58,6 +58,7 @@ struct ipc_namespace {
 
 	/* user_ns which owns the ipc ns */
 	struct user_namespace *user_ns;
+	struct ucounts *ucounts;
 
 	struct ns_common ns;
 };
diff --git a/include/linux/mount.h b/include/linux/mount.h
index 54a594d49733..1172cce949a4 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -96,4 +96,6 @@ extern void mark_mounts_for_expiry(struct list_head *mounts);
 
 extern dev_t name_to_dev_t(const char *name);
 
+extern unsigned int sysctl_mount_max;
+
 #endif /* _LINUX_MOUNT_H */
diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
index 918b117a7cd3..34cce96741bc 100644
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -40,6 +40,7 @@ struct pid_namespace {
 	struct fs_pin *bacct;
 #endif
 	struct user_namespace *user_ns;
+	struct ucounts *ucounts;
 	struct work_struct proc_work;
 	kgid_t pid_gid;
 	int hide_pid;
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
index de0e7719d4c5..12cb8bd81d2d 100644
--- a/include/linux/proc_ns.h
+++ b/include/linux/proc_ns.h
@@ -18,6 +18,8 @@ struct proc_ns_operations {
 	struct ns_common *(*get)(struct task_struct *task);
 	void (*put)(struct ns_common *ns);
 	int (*install)(struct nsproxy *nsproxy, struct ns_common *ns);
+	struct user_namespace *(*owner)(struct ns_common *ns);
+	struct ns_common *(*get_parent)(struct ns_common *ns);
 };
 
 extern const struct proc_ns_operations netns_operations;
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index ecc3e07c6e63..adf4e51cf597 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -158,8 +158,7 @@ struct ctl_table_set {
 
 struct ctl_table_root {
 	struct ctl_table_set default_set;
-	struct ctl_table_set *(*lookup)(struct ctl_table_root *root,
-					   struct nsproxy *namespaces);
+	struct ctl_table_set *(*lookup)(struct ctl_table_root *root);
 	void (*set_ownership)(struct ctl_table_header *head,
 			      struct ctl_table *table,
 			      kuid_t *uid, kgid_t *gid);
diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
index 9217169c64cb..eb209d4523f5 100644
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -22,6 +22,19 @@ struct uid_gid_map {	/* 64 bytes -- 1 cache line */
 
 #define USERNS_INIT_FLAGS USERNS_SETGROUPS_ALLOWED
 
+struct ucounts;
+
+enum ucount_type {
+	UCOUNT_USER_NAMESPACES,
+	UCOUNT_PID_NAMESPACES,
+	UCOUNT_UTS_NAMESPACES,
+	UCOUNT_IPC_NAMESPACES,
+	UCOUNT_NET_NAMESPACES,
+	UCOUNT_MNT_NAMESPACES,
+	UCOUNT_CGROUP_NAMESPACES,
+	UCOUNT_COUNTS,
+};
+
 struct user_namespace {
 	struct uid_gid_map	uid_map;
 	struct uid_gid_map	gid_map;
@@ -39,10 +52,30 @@ struct user_namespace {
 	struct key		*persistent_keyring_register;
 	struct rw_semaphore	persistent_keyring_register_sem;
 #endif
+	struct work_struct	work;
+#ifdef CONFIG_SYSCTL
+	struct ctl_table_set	set;
+	struct ctl_table_header *sysctls;
+#endif
+	struct ucounts		*ucounts;
+	int ucount_max[UCOUNT_COUNTS];
+};
+
+struct ucounts {
+	struct hlist_node node;
+	struct user_namespace *ns;
+	kuid_t uid;
+	atomic_t count;
+	atomic_t ucount[UCOUNT_COUNTS];
 };
 
 extern struct user_namespace init_user_ns;
 
+bool setup_userns_sysctls(struct user_namespace *ns);
+void retire_userns_sysctls(struct user_namespace *ns);
+struct ucounts *inc_ucount(struct user_namespace *ns, kuid_t uid, enum ucount_type type);
+void dec_ucount(struct ucounts *ucounts, enum ucount_type type);
+
 #ifdef CONFIG_USER_NS
 
 static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
@@ -54,12 +87,12 @@ static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
 
 extern int create_user_ns(struct cred *new);
 extern int unshare_userns(unsigned long unshare_flags, struct cred **new_cred);
-extern void free_user_ns(struct user_namespace *ns);
+extern void __put_user_ns(struct user_namespace *ns);
 
 static inline void put_user_ns(struct user_namespace *ns)
 {
 	if (ns && atomic_dec_and_test(&ns->count))
-		free_user_ns(ns);
+		__put_user_ns(ns);
 }
 
 struct seq_operations;
@@ -73,6 +106,8 @@ extern ssize_t proc_setgroups_write(struct file *, const char __user *, size_t,
 extern int proc_setgroups_show(struct seq_file *m, void *v);
 extern bool userns_may_setgroups(const struct user_namespace *ns);
 extern bool current_in_userns(const struct user_namespace *target_ns);
+
+struct ns_common *ns_get_owner(struct ns_common *ns);
 #else
 
 static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
@@ -106,6 +141,11 @@ static inline bool current_in_userns(const struct user_namespace *target_ns)
 {
 	return true;
 }
+
+static inline struct ns_common *ns_get_owner(struct ns_common *ns)
+{
+	return ERR_PTR(-EPERM);
+}
 #endif
 
 #endif /* _LINUX_USER_H */
diff --git a/include/linux/utsname.h b/include/linux/utsname.h
index 5093f58ae192..60f0bb83b313 100644
--- a/include/linux/utsname.h
+++ b/include/linux/utsname.h
@@ -24,6 +24,7 @@ struct uts_namespace {
 	struct kref kref;
 	struct new_utsname name;
 	struct user_namespace *user_ns;
+	struct ucounts *ucounts;
 	struct ns_common ns;
 };
 extern struct uts_namespace init_uts_ns;