CRED: Separate task security context from task_struct

Separate the task security context from task_struct.  At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/selinux/exports.c b/security/selinux/exports.c
index 64af2d3..cf02490 100644
--- a/security/selinux/exports.c
+++ b/security/selinux/exports.c
@@ -39,7 +39,7 @@
 int selinux_secmark_relabel_packet_permission(u32 sid)
 {
 	if (selinux_enabled) {
-		struct task_security_struct *tsec = current->security;
+		struct task_security_struct *tsec = current->cred->security;
 
 		return avc_has_perm(tsec->sid, sid, SECCLASS_PACKET,
 				    PACKET__RELABELTO, NULL);