security: remove security_sb_post_mountroot hook

The security_sb_post_mountroot() hook is long-since obsolete, and is
fundamentally broken: it is never invoked if someone uses initramfs.
This is particularly damaging, because the existence of this hook has
been used as motivation for not using initramfs.

Stephen Smalley confirmed on 2007-07-19 that this hook was originally
used by SELinux but can now be safely removed:

     http://marc.info/?l=linux-kernel&m=118485683612916&w=2

Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 0 insertions, 6 deletions

diff --git a/security/dummy.c b/security/dummy.c
index a3b29d0d00e5..8e34e03415f8 100644
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -225,11 +225,6 @@ static void dummy_sb_post_remount (struct vfsmount *mnt, unsigned long flags,
 }
 
 
-static void dummy_sb_post_mountroot (void)
-{
-        return;
-}
-
 static void dummy_sb_post_addmount (struct vfsmount *mnt, struct nameidata *nd)
 {
         return;
@@ -1017,7 +1012,6 @@ void security_fixup_ops (struct security_operations *ops)
         set_to_dummy_if_null(ops, sb_umount_close);
         set_to_dummy_if_null(ops, sb_umount_busy);
         set_to_dummy_if_null(ops, sb_post_remount);
-        set_to_dummy_if_null(ops, sb_post_mountroot);
         set_to_dummy_if_null(ops, sb_post_addmount);
         set_to_dummy_if_null(ops, sb_pivotroot);
         set_to_dummy_if_null(ops, sb_post_pivotroot);