#include <linux/uaccess.h>
#include <linux/ctype.h>
#include <linux/projid.h>
+#include <linux/fs_struct.h>
static struct kmem_cache *user_ns_cachep __read_mostly;
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.
set_cred_user_ns(new, ns);
+ update_mnt_policy(ns);
+
return 0;
}
if (atomic_read(¤t->mm->mm_users) > 1)
return -EINVAL;
+ if (current->fs->users != 1)
+ return -EINVAL;
+
if (!ns_capable(user_ns, CAP_SYS_ADMIN))
return -EPERM;