1 files changed, 48 insertions, 3 deletions

diff --git a/kernel/utsname.c b/kernel/utsname.c
index 8a82b4b8ea52..bff131b9510a 100644
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -14,6 +14,8 @@
 #include <linux/utsname.h>
 #include <linux/err.h>
 #include <linux/slab.h>
+#include <linux/user_namespace.h>
+#include <linux/proc_fs.h>
 
 static struct uts_namespace *create_uts_ns(void)
 {
@@ -30,7 +32,8 @@ static struct uts_namespace *create_uts_ns(void)
  * @old_ns: namespace to clone
  * Return NULL on error (failure to kmalloc), new ns otherwise
  */
-static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns)
+static struct uts_namespace *clone_uts_ns(struct task_struct *tsk,
+                                          struct uts_namespace *old_ns)
 {
         struct uts_namespace *ns;
 
@@ -40,6 +43,7 @@ static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns)
 
         down_read(&uts_sem);
         memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
+        ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns);
         up_read(&uts_sem);
         return ns;
 }
@@ -50,8 +54,10 @@ static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns)
  * utsname of this process won't be seen by parent, and vice
  * versa.
  */
-struct uts_namespace *copy_utsname(unsigned long flags, struct uts_namespace *old_ns)
+struct uts_namespace *copy_utsname(unsigned long flags,
+                                   struct task_struct *tsk)
 {
+        struct uts_namespace *old_ns = tsk->nsproxy->uts_ns;
         struct uts_namespace *new_ns;
 
         BUG_ON(!old_ns);
@@ -60,7 +66,7 @@ struct uts_namespace *copy_utsname(unsigned long flags, struct uts_namespace *ol
         if (!(flags & CLONE_NEWUTS))
                 return old_ns;
 
-        new_ns = clone_uts_ns(old_ns);
+        new_ns = clone_uts_ns(tsk, old_ns);
 
         put_uts_ns(old_ns);
         return new_ns;
@@ -71,5 +77,44 @@ void free_uts_ns(struct kref *kref)
         struct uts_namespace *ns;
 
         ns = container_of(kref, struct uts_namespace, kref);
+        put_user_ns(ns->user_ns);
         kfree(ns);
 }
+
+static void *utsns_get(struct task_struct *task)
+{
+        struct uts_namespace *ns = NULL;
+        struct nsproxy *nsproxy;
+
+        rcu_read_lock();
+        nsproxy = task_nsproxy(task);
+        if (nsproxy) {
+                ns = nsproxy->uts_ns;
+                get_uts_ns(ns);
+        }
+        rcu_read_unlock();
+
+        return ns;
+}
+
+static void utsns_put(void *ns)
+{
+        put_uts_ns(ns);
+}
+
+static int utsns_install(struct nsproxy *nsproxy, void *ns)
+{
+        get_uts_ns(ns);
+        put_uts_ns(nsproxy->uts_ns);
+        nsproxy->uts_ns = ns;
+        return 0;
+}
+
+const struct proc_ns_operations utsns_operations = {
+        .name           = "uts",
+        .type           = CLONE_NEWUTS,
+        .get            = utsns_get,
+        .put            = utsns_put,
+        .install        = utsns_install,
+};
+