capabilities: do not special case exec of init

When the global init task is exec'd we have special case logic to make sure
the pE is not reduced.  There is no reason for this.  If init wants to drop
it's pE is should be allowed to do so.  Remove this special logic.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>

security/commoncap.c

@@ -529,15 +529,10 @@ int cap_bprm_set_creds(struct linux_binprm *bprm)
 	new->suid = new->fsuid = new->euid;
 	new->sgid = new->fsgid = new->egid;
 
-	/* For init, we want to retain the capabilities set in the initial
-	 * task.  Thus we skip the usual capability rules
-	 */
-	if (!is_global_init(current)) {
-		if (effective)
-			new->cap_effective = new->cap_permitted;
-		else
-			cap_clear(new->cap_effective);
-	}
+	if (effective)
+		new->cap_effective = new->cap_permitted;
+	else
+		cap_clear(new->cap_effective);
 	bprm->cap_effective = effective;
 
 	/*