3 files changed, 15 insertions, 1 deletions

diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index c1c3dc1c6023..bea15bdf82b0 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -181,6 +181,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
         int nr;
         int rc;
         struct task_struct *task, *me = current;
+        int init_pids = thread_group_leader(me) ? 1 : 2;
 
         /* Don't allow any more processes into the pid namespace */
         disable_pid_allocation(pid_ns);
@@ -230,7 +231,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
          */
         for (;;) {
                 set_current_state(TASK_UNINTERRUPTIBLE);
-                if (pid_ns->nr_hashed == 1)
+                if (pid_ns->nr_hashed == init_pids)
                         break;
                 schedule();
         }
diff --git a/kernel/user.c b/kernel/user.c
index e81978e8c03b..8e635a18ab52 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -51,6 +51,8 @@ struct user_namespace init_user_ns = {
         .owner = GLOBAL_ROOT_UID,
         .group = GLOBAL_ROOT_GID,
         .proc_inum = PROC_USER_INIT_INO,
+        .may_mount_sysfs = true,
+        .may_mount_proc = true,
 };
 EXPORT_SYMBOL_GPL(init_user_ns);
 
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index b14f4d342043..a54f26f82eb2 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -61,6 +61,15 @@ int create_user_ns(struct cred *new)
         kgid_t group = new->egid;
         int ret;
 
+        /*
+         * Verify that we can not violate the policy of which files
+         * may be accessed that is specified by the root directory,
+         * by verifing that the root directory is at the root of the
+         * mount namespace which allows all files to be accessed.
+         */
+        if (current_chrooted())
+                return -EPERM;
+
         /* The creator needs a mapping in the parent user namespace
          * or else we won't be able to reasonably tell userspace who
          * created a user_namespace.
@@ -87,6 +96,8 @@ int create_user_ns(struct cred *new)
 
         set_cred_user_ns(new, ns);
 
+        update_mnt_policy(ns);
+
         return 0;
 }